Chapter 19: The Wrist and Hand

The wrist is the final link of joints that positions the hand for functional activities. It has the significant function of controlling the length-tension relationship of the multiarticular muscles of the hand as they adjust to various activities and grips.⁶ The hand is a valuable tool through which we control and manipulate our environment and express ideas and talents. It also has an important function of providing sensory feedback to the central nervous system.

This chapter is divided into three major sections. The first section briefly reviews the rather complex structure and function of the wrist and hand—information that is important to know in order to effectively treat hand problems. The second section describes common disorders and guidelines for conservative and postoperative management. The last section describes exercise techniques commonly used to meet the goals of treatment during the stages of tissue healing and phases of rehabilitation.

The bones of the wrist include the distal radius, scaphoid (S), lunate (L), triquetrum (Tri), pisiform (P), trapezium (Tm), trapezoid (Tz), capitate (C), and hamate (H). Five metacarpals and 14 phalanges make up the hand and the five digits (Fig. 19.1).

Joints of the Wrist and Hand

Wrist Joint: Characteristics and Arthrokinematics

The distal radioulnar (RU) joint is not part of the wrist joint, although pain and impairments in this forearm articulation are often described by the patient as wrist pain. Structure and function of the RU joints are described in Chapter 18.

The wrist joint is multiarticular and is made up of two compound joints. It is biaxial, allowing flexion (volar flexion), extension (dorsiflexion), radial deviation (abduction), and ulnar deviation (adduction). Stability is provided by numerous ligaments: the ulnar and radial collateral, the dorsal and volar (palmar) radiocarpal, the ulnocarpal, and the intercarpal.

The pisiform is categorized as a carpal and aligned volar to the triquetrum in the proximal row of carpals. It is not part of the wrist joint per se but functions as a sesamoid bone in the flexor carpi ulnaris tendon.

Radiocarpal Joint

Characteristics. The radiocarpal (RC) joint is enclosed in a loose but strong capsule that is reinforced by the ligaments shared with the midcarpal joint. The biconcave articulating surface is the distal end of the radius and radioulnar disk (discus articularis); it is angled slightly volarward and ulnarward. The biconvex articulating surface is the combined proximal surface of the scaphoid, lunate, and triquetrum. The triquetrum primarily articulates with the disk. These three carpals are bound together with numerous interosseous ligaments.

Arthrokinematics. With motions of the wrist, the convex proximal row of carpals slides in the direction opposite the physiological motion of the hand. The arthrokinematics are summarized in Box 19.1.

Midcarpal Joint

Characteristics. The midcarpal joint is a compound joint between the two rows of carpals. It has a capsule that is also continuous with the intercarpal articulations. The combined distal surfaces of the scaphoid, lunate, and triquetrum articulate with the combined proximal surfaces of the trapezium, trapezoid, capitate, and hamate.

Arthrokinematics. The articulating surfaces of the capitate and hamate are, in essence, convex and slide on the concave articulating surfaces of a portion of the scaphoid, lunate, and triquetrum, so with flexion and extension, as well as radial and ulnar deviation, their combined surfaces slide opposite the physiological motion.

The articulating surfaces of the trapezium and trapezoid are concave and slide on the convex distal surface of the scaphoid so with flexion and extension their combined surfaces slide in the same direction as the physiological motion. Because the trapezoid is bound to the capitate, they cannot slide in opposite directions during radial and ulnar deviation. The trapezii (the trapezium and trapezoid), therefore, slide in a dorsal direction on the scaphoid during radial deviation and in a volar direction during ulnar deviation.⁶²

Physiological motions of the wrist result in a complex motion between the proximal and distal row of carpals. Because the concave trapezii slide in a dorsal direction on the scaphoid and the convex capitate and hamate slide in a volar direction on the lunate and triquetrum during extension and radial deviation, the resulting motion is a supination twist of the distal row on the proximal row. A pronation twist occurs during flexion and ulnar deviation as the trapezii slide volarly and the capitate and hamate slide dorsally.⁶

These arthrokinematic relationships are summarized in Box 19.1.

Hand Joints: Characteristics and Arthrokinematics

Carpometacarpal Joints of Digits 2 through 5

Characteristics. The carpometacarpal (CMC) joints are enclosed in a common joint cavity and include the articulations of each metacarpal with the distal row of carpals and the articulations between the bases of each metacarpal.

The joints of digits 2, 3, and 4 are plane uniaxial joints; the joint of digit 5 is biaxial. They are supported by transverse and longitudinal ligaments. The fifth metacarpal is most mobile, with the fourth being the next most mobile. Flexion of the metacarpals and additional adduction of the fifth contribute to cupping (arching) of the hand, which improves the ability of the hand to grasp objects of various sizes. Extension of the metacarpals contributes to flattening of the hand, which improves the ability to release objects.

Arthrokinematics. The proximal surfaces slide in a volar direction with flexion and in a dorsal direction with extension motions in the hand (see Box 19.1).

Carpometacarpal Joint of the Thumb (Digit 1)

Characteristics. The CMC joint of the thumb is a saddle-shaped (sellar) biaxial joint between the trapezium and base of the first metacarpal. It has a lax capsule and wide range of motion (ROM), which allows the thumb to move away from the palm of the hand for opposition in prehension activities.

Arthrokinematics. For flexion/extension of the thumb (components of opposition/reposition, respectively) in the frontal plane, the surface of the trapezium is convex, and the base of the metacarpal is concave; therefore, its surface slides in the same direction as the angulating bone. For abduction/adduction in the sagittal plane, the trapezium surface is concave and the metacarpal is convex; therefore, the surface of the metacarpal slides in the opposite direction of the physiological motion (see Box 19.1).

Metacarpophalangeal Joints of Digits 2–5

Characteristics. The metacarpophalangeal (MCP) joints are biaxial condyloid joints. Each joint is supported by a volar and two collateral ligaments. The collaterals become taut in full flexion and prevent abduction and adduction in this position.

Arthrokinematics. The distal end of each metacarpal is convex and the proximal phalanx concave. The proximal surface of the proximal phalanx rolls and slides in the same direction as the physiological motion (see Box 19.1).

Interphalangeal Joints and MCP Joint of the Thumb

Characteristics. There is a proximal (PIP) and distal (DIP) interphalangeal joint for each digit, 2 through 5. The thumb has only one interphalangeal joint, although the MCP joint of the thumb is uniaxial and therefore functions similarly to the IP joints. The MCP joint of the thumb differs in that it is reinforced by two sesamoid bones on the volar surface, which improve the leverage of the flexor pollicis brevis muscle. Each of these joints is a uniaxial hinge joint.

The capsule of each joint is reinforced with collateral ligaments, which are taut in extension. Going radial to ulnar in digits 2 through 5, there is increasing flexion/extension range in the joints. This allows for greater opposition of the ulnar fingers to the thumb and also causes a potentially tighter grip on the ulnar side of the hand.

Arthrokinematics. The articulating surface at the distal end of each phalanx is convex; the articulating surface at the proximal end of each phalanx is concave. Therefore, the proximal surface of each phalanx rolls and slides in the same direction as the physiological motion (see Box 19.1).

Hand Function

Muscles of the Wrist and Hand

The complex function of the hand occurs as a result of an intricate balance and control of forces between the extrinsic and intrinsic muscles of the wrist and hand. The primary and secondary actions of the wrist and hand muscles are summarized in Table 19.1 and depicted in Figure 19.2.

Length-Tension Relationships

The position of the wrist controls the length of the extrinsic muscles of the digits. As the fingers or thumb flex, the wrist extensor muscles must stabilize the wrist to prevent the flexor digitorum profundus and flexor digitorum superficialis or the flexor pollicis longus from simultaneously flexing the wrist. As the grip becomes stronger, synchronous wrist extension lengthens the extrinsic flexor tendons across the wrist and maintains a more favorable overall length of the musculotendinous unit for a stronger contraction.

For strong finger or thumb extension, the wrist flexor muscles stabilize or flex the wrist so the extensor digitorum communis, extensor indicis, extensor digiti minimi, or extensor pollicis longus muscles can function more efficiently. In addition, there is ulnar deviation; the flexor and extensor carpi ulnaris muscles are both active as the hand opens.

Extensor Mechanism

Structurally, the extensor hood (extensor expansion) is made up of the extensor digitorum communis tendon, its connective tissue expansion, and fibers from the tendons of the dorsal and volar interossei and lumbricals (Fig. 19.3).⁶ Each structure that is a part of the hood has an effect on the extensor mechanism.

• An isolated contraction of the extensor digitorum produces clawing of the fingers—MCP hyperextension with IP flexion from passive pull of the extrinsic flexor tendons, also called the hook position.

• PIP and DIP extension occurs concurrently and can be caused by the interossei or lumbrical muscles through their pull on the extensor hood.

• There must be tension in the extensor digitorum communis tendon for there to be interphalangeal extension. This occurs either by active contraction of the muscle, causing MCP extension concurrently as the intrinsic muscles contract, or by stretch of the tendon, which occurs with MCP flexion.

Control of the Unloaded (Free) Hand

Anatomical factors, muscular contraction, and viscoelastic properties of the muscles influence finger motion.⁶

• When only the extrinsic muscles contract, clawing motions occur in the digits.

• Closing motions can occur only with extrinsic muscle contractions but also require the viscoelastic force of the biarticular interossei.

• Opening motions require synergistic contraction of the extrinsic extensor and the lumbrical muscles.

• Reciprocal motion of MCP flexion and IP extension is caused by the interossei. The lumbrical removes the viscoelastic tension from the profundus tendon and assists IP extension.

Grips and Prehension Patterns

The nature of the intended activity dictates the type of grip used.^{6,61,71,85,86}

Power Grips

Description. Power grips involve clamping an object with partially flexed fingers against the palm of the hand and with counter pressure from the adducted thumb. Power grips are primarily isometric functions. The fingers are flexed, laterally rotated, and ulnarly deviated. The amount of flexion varies with the object held. The thumb reinforces the fingers and helps make small adjustments to control the direction of the force. Varieties include cylindrical grip, spherical grip, hook grip, and lateral prehension.

Muscle control. The muscles primarily function with isometric contractions.^6,86

• Extrinsic finger flexors provide the major gripping force.

• The extensor digitorum provides a compressive force to the MCP joints, which increases stability and also provides a balancing force for the flexors.

• Interossei rotate the first phalanx for positioning to compress the external object and also flex the MCP joint.

• With the exception of the fourth lumbrical, lumbricals do not participate in the power grip (except the fourth).

• The thenar muscles and adductor pollicis provide compressive forces against the object being gripped.

Precision Patterns

Description. Prehension patterns involve manipulating an object that is not in contact with the palm of the hand between the opposing abducted thumb and fingers. The muscles primarily function isotonically. The sensory surfaces of the digits are used for maximum sensory input to influence delicate adjustments. With small objects, precise handling occurs primarily between the thumb and index finger. Varieties include pad-to-pad, tip-to-tip, and pad-to-side prehension.

Muscle control. The primary dynamic function of the muscles includes the following.^6,86

• Extrinsic muscles provide the compressive force to hold the objects between the fingers and thumb.

• For manipulation of an object, the interossei abduct and adduct the fingers; the thenar muscles control movement of the thumb; and the lumbricals help move the object away from the palm of the hand. The amount of participation of each muscle varies with the amount and direction of motion.

Combined Grips

Description. Combined grips involve digits 1 and 2 (and sometimes 3) performing precision activities, whereas digits 3 through 5 supplement with power.

Pinch. Pinch requires holding an object between the thumb and index or middle finger, as in precision handling, but may require primarily an isometric hold. The thenar eminence muscles, the adductor pollicis, the interossei, and the extrinsic flexors provide compression between the thumb and fingers. The lumbricals also participate.

Major Nerves Subject to Pressure and Trauma at the Wrist and Hand

For a detailed description of peripheral nerve injuries and entrapments in the wrist and hand region, as well as complex regional pain syndromes (including reflex sympathetic dystrophy) and their management, see Chapter 13.

Nerve Disorders in the Wrist

Median nerve. The most common site for compression of the median nerve is the carpal tunnel.

Ulnar nerve. The most common site for compression of the ulnar nerve is in the ulnar tunnel (also called Guyon's canal).

Referred Pain and Sensory Patterns

The hand is the terminal point for the C6, C7, and C8 nerve roots coursing through the median, ulnar, and radial nerves (see Figs. 13.5, 13.6, and 13.7). Injury or entrapment of these nerves may occur anywhere along their course, from the cervical spine to their termination. What the patient perceives as pain or a sensory disturbance in the hand may be from injury of the nerve anywhere along its course, or the pain may derive from irritation of tissue of common segmental origin, such as the zygapophyseal facet joints of the spine. For treatment to be effective, it must be directed to the source of the problem, not to the site where the patient perceives the pain or sensory changes. Therefore, a thorough history is taken and examination of the entire upper quarter must be done, including the cervical spine when referred pain patterns or sensory changes are reported by the patient.^37,74

To make sound clinical decisions when treating patients with wrist and hand disorders, it is necessary to understand the various pathologies, surgical procedures, and associated precautions and to identify presenting structural and functional impairments, activity limitations (functional limitations), and possible participation restrictions (disabilities). In this section, common pathologies and surgeries are presented and are related to corresponding preferred practice patterns (groupings of impairments) described in the Guide to Physical Therapist Practice³ (Table 19.2). Conservative and postoperative management of these conditions is also described in this section.

Joint Hypomobility: Nonoperative Management

Pathologies, such as rheumatoid arthritis (RA) and degenerative joint disease (DJD), affect the joints of the wrist and hand and may have a significant effect on the functional abilities of an individual as a result of pain, impaired mobility, and potential joint deformities. Impaired joint, tendon, and muscle mobility also occurs any time joints are immobilized due to fractures, trauma, or surgery. Chapter 11 describes the etiology and general guidelines for management of impairments due to these joint pathologies. This section focuses on specific interventions for the wrist and hand.

Common Joint Pathologies and Associated Impairments

Rheumatoid Arthritis

The following is a summary of signs, symptoms, and resulting impairments typically seen in the wrist and hand with RA.^{4,13,87,94,121}

Acute stage. There is pain, swelling, warmth, and limited motion from synovial inflammation (synovitis) and tissue proliferation, most commonly in the MCP, PIP, and wrist joints bilaterally. There is also inflammation (tenosynovitis) and synovial proliferation in the extrinsic tendons and tendon sheaths. In addition:

• Progressive muscle weakness and imbalances in length and strength between agonists and antagonists and between intrinsic and extrinsic muscles occur.

• Carpal tunnel syndrome may occur in conjunction with tenosynovitis due to compression of the median nerve from the swollen tissue.

• General systemic as well as muscular fatigue occurs.

Advanced stages. Joint capsule weakening, cartilage destruction, bone erosion, and tendon rupture, as well as imbalances in musculotendinous forces, lead to joint instabilities, subluxations, and deformities (Fig. 19.4). Typical deformities and the pathomechanics in the hand include:

• Volar subluxation of the triquetrum on the articular disk and ulna. The extensor carpi ulnaris tendon displaces volarly and causes a flexor force at the wrist joint.

• Ulnar subluxation of the carpals. This causes radial deviation of the wrist.

• Ulnar drift of the fingers and volar subluxation of the proximal phalanx. There is stretching or rupture of the collateral ligaments at the MCP joints and a bowstringing effect from the extrinsic tendons.¹³

• Swan-neck deformity. Laxity of the PIP joint with an overstretched palmar plate and bowstringing of the lateral bands of the extensor hood result in hyperextension of the PIP and flexion of the DIP joints (Fig. 19.5A). Tight or overactive interossei muscles pulling on the extensor tendon reinforces the hyperextension of the hypermobile PIP joints, and increased passive tension in the flexor digitorum profundus tendon causes flexion of the DIP joint.

• Boutonnière deformity. Rupture of the central band (central slip) of the extensor hood results in the lateral bands of the extensor apparatus (extensor hood) slipping in a volar direction to the PIP joint, causing PIP flexion and DIP extension (Fig. 19.5B).

• Zigzag deformity of the thumb. Muscle imbalances and ligamentous laxity lead to metacarpal dislocation of the thumb and deformities similar to swan-neck or boutonnière deformity. Tightness in the adductor pollicis contributes to deformities in the thumb.⁸⁷

Degenerative Joint Disease/Osteoarthritis and Posttraumatic Arthrosis

Age and repetitive joint trauma lead to degenerative cartilaginous and boney changes in susceptible joints. DJD, or osteoarthritis (OA), most commonly involves the trapezioscaphoid articulation, CMC joint of the thumb, and DIP joints of the digits, although the effects of trauma can occur in any joint.

Posttraumatic arthrosis can develop in any joint of the wrist or hand as the result of a severe intra-articular fracture or fracture-dislocation. For example, at the wrist, deficiency of the scapholunate interosseous ligament as the result of a severe wrist sprain can alter joint alignment, which can cause articular degeneration over time. In the fingers, the PIP joint is a common site of articular fracture and subsequent joint degeneration.

The following is a summary of signs, symptoms, and resulting impairments commonly seen in DJD or posttraumatic arthrosis.¹²⁶

Acute stage. During the early stages of DJD, symptoms include achiness and feelings of stiffness, which abate with movement. Following stressful activities or trauma, joint swelling, warmth, and restricted and painful motion occur.

Advanced stages. With degeneration, there is capsular laxity resulting in hypermobility or instability; with progression, contractures and limited motion develop. Affected joints may become enlarged or sublux (Fig. 19.6). Limitation of both flexion and extension with a firm capsular end-feel develops in the affected joints. There is general muscle weakness, weak grip strength, and poor muscular endurance. Pain may also be a limiting factor in pinch and gripping activities.

PRECAUTION: After trauma, the therapist must be alert to signs of a fracture in the wrist or hand because small bone fractures may not show on radiographs for as many as 2 weeks. Signs include swelling, muscle spasm when passive motion is attempted, increased pain when the involved bone is stressed (e.g., deviation toward the involved bone), and tenderness on palpation over the fracture site.^37,80

Postimmobilization Hypomobility

Immobilization may be necessary following a fracture, surgery, or trauma, or it may be used to rest a part when an individual sustains repetitive stress. Structural and functional impairments may occur from the lack of motion and muscle contraction, including:

• Decreased ROM and decreased joint play with firm end-feel and pain on overpressure.

• Tendon adhesions as the result of inflammation in a tendon or its sheath.

• Decreased muscle performance including muscle weakness, weak grip strength, decreased flexibility, and decreased muscle endurance.

Common Activity Limitations and Participation Restrictions (Functional Limitations/Disabilities)

When joint pathology is acute, many prehension activities are painful, interfering with activities of daily living (ADL and IADL), such as dressing, eating, grooming, and toileting or almost any functional activity that requires pinching, gripping, and fine-finger dexterity, including writing and typing.

Depending on which joints are involved; the amount of restricted movement and residual weakness, fatigue, or dexterity loss; and the type of grip or amount of precision handling required, functional loss may be minor or significant.

Joint Hypomobility: Management—Protection Phase

General guidelines for managing acute joint lesions are described in Chapter 11, with special concerns for patients with RA and OA summarized in Boxes 11.2 and 11.4, respectively.

Control Pain and Protect Joints

Patient education. Teach the patient how to protect involved joints and control pain with activity modification, ROM exercises, and appropriate use of a splint.

Pain management. In addition to physician-prescribed medications or nonsteroidal anti-inflammatory medications and modalities, gentle grade I or II distraction and oscillation techniques may inhibit pain and move synovial fluid for nutrition in the involved joints.

Splinting. Use a splint to rest and protect the involved joints. Instruct the patient to remove the splint for brief periods of nonstressful motion throughout the day.

Activity modification. Analyze the patient's daily activities and recommend adaptations or assistive devices to minimize repetitive or excessive stresses on the joints. This is particularly important for patients with chronic arthritic disorders to prevent repetitive trauma and to minimize joint-deforming forces. Examples are summarized in Box 19.2.

Maintain Joint and Tendon Mobility and Muscle Integrity

Passive, assistive, or active ROM. It is important to move the joints as tolerated, because immobility of the hand quickly leads to muscle imbalance and contracture formation or further articular deterioration. Aquatic therapy is an effective method of combining nonstressful, nonweight-bearing exercises with therapeutic heat.

Tendon-gliding exercises. Have the patient perform full motion in the uninvolved joints and as much motion as possible in the involved joints to prevent adhesions between the long tendons or between the tendons and their synovial sheaths.⁵² Tendon-gliding exercises are described in the exercise section of this chapter.

Multiple-angle muscle setting exercises. Perform gentle isometrics of all wrist and hand musculature. Resistive ROM exercises usually are not tolerated if there is joint effusion or inflammation; therefore, isometric resistance within the tolerance of pain is performed.

Joint Hypomobility: Management—Controlled Motion and Return to Function Phases

With joint pathology, increase ROM by utilizing joint mobilization techniques to stretch the capsule⁹⁷ as well as passive stretching and muscle inhibition techniques to elongate the periarticular connective tissue and musculotendinous units following the principles described in Chapters 4 and 5. It is also critical to determine if scar tissue has formed in the long tendon sheaths in the hand and if so, attempt to re-establish smooth tendon gliding.

Increase Joint Play and Accessory Motions

Joint mobilization techniques. Determine which of the articulations of the distal RU, wrist, hand, or digits are restricted because of decreased joint play, and apply grade III sustained or grade IV oscillation techniques to stretch the capsules. See Figures 5.33,5.34,5.35,5.36,5.37,5.38,5.39,5.40,5.41,5.42,5.43 for mobilizing restricted joints of the distal forearm, wrist, hand, and digits.

PRECAUTIONS: For patients with RA, modify the intensity of joint mobilization and stretching techniques that are used to counter any restrictions. This is necessary because the disease process and steroid therapy weaken the tensile quality of the connective tissue, and consequently the tissue is more easily torn.

Unlock a subluxated ulnomeniscal-triquetral joint. The mechanism of the dysfunction is not clear, but some patients describe locking in the wrist and an inability to supinate the forearm. The meniscus may be displaced and be the cause of the blocked motion. The following techniques may free up the motion.

• Apply a volar glide to the ulna on a stabilized triquetrum (similar to Fig. 5.38).

• Self-mobilization. Have the patient grasp the distal ulna with the fingers of the opposite hand, place the thumb on the palmar surface of the triquetrum just medial to the pisiform, and then press with the thumb, causing a dorsal glide of the triquetrum on the radioulnar disk and ulna (Fig. 19.7).

Improve Joint Tracking and Pain-Free Motion

Mobilization with movement (MWM) techniques may be applied to increase ROM and/or decrease the pain associated with movement.⁸¹ (The principles of MWM are described in Chapter 5.)

MWM of the wrist. Have the patient seated with the elbow flexed and forearm supinated (patient's palm facing toward his or her face); stabilize the distal radius with your hand placed around the lateral aspect of the forearm.

• Apply a pain-free lateral glide to the proximal row of carpals, utilizing the web space of your other hand. Have the patient then perform active wrist extension or flexion to the end of the available range, and with his or her free hand, apply a passive stretch at the end of the range (Fig. 19.8).

• An internal or external rotation of the carpals relative to the radius may need to be combined with the glide to achieve pain-free, end-range loading.

• The intercarpal joint may require specific anterior-posterior gliding of one proximal row of carpals relative to its distal row neighbor combined with active physiologic motion to the end of the range. The mobilization and movement are pain-free. While holding the mobilization force, ask the patient to do repetitive gripping activities or resisted wrist motions.

MWM of the MCP and IP joints of the digits. Medially or laterally glide the involved phalanx in a painless direction, then have the patient actively flex or extend the finger and apply a pain-free, end-range stretch. Internal or external rotation of the more distal phalanx may be required in conjunction with the medial or lateral glide to achieve painless end-range overpressure.⁸¹

Improve Mobility, Strength, and Function

Carefully examine the multijoint and intrinsic muscles for restricted motion due to contractures or adhesions and poor movement patterns due to weakness or imbalances in strength. Stretching, tendon gliding, and strengthening exercises are described in the exercise sections of this chapter. Utilize techniques that specifically address the impairments the patient has. Once range is gained, it is critical that the patient uses the new range with active ROM and functional activities.

Neuromuscular control and strength. Progress exercises with controlled and nondestructive force to increase strength and muscle balance between antagonists and to progress endurance training. With pathological joints, use caution when applying weights so as not to stress the joints beyond the capability of the stabilizing tissues.

Functional activities. Develop exercises that prepare the patient for functional activities. Consider prehension patterns that are required for the patient's job, recreational, and daily activities. Include exercises that require coordination and fine finger dexterity.

Conditioning exercises. Initiate physical conditioning exercises using activities that do not provoke joint symptoms, such as aquatic exercises or cycling.

Joint protection. Reinforce use of joint protection techniques as summarized in Box 19.2.

Joint Surgery and Postoperative Management

Long-standing RA, OA, or posttraumatic arthritis affecting the joints and soft tissues of the wrist and hand can lead to chronic pain, instability and deformity of joints, restricted ROM, loss of strength in the hand, and impaired function of the upper extremity. When nonoperative management is not sufficient, surgical intervention coupled with individually designed and carefully supervised postoperative rehabilitation is indicated to improve and restore function.

Some of the more common surgical options for management of arthritis of the wrist and hand are listed in Box 19.3. Refer to Table 19.2 to see the groupings of impairments typically associated with each of these surgeries.

Soft tissue procedures, such as synovectomy, tenosynovectomy for chronic tenosynovitis of the extensor and flexor tendons of the wrist, repair of ruptured tendons, capsulotomy or release of other soft tissues for correcting a deformity, or muscle balancing of the wrist or finger joints, are employed independently or concomitantly when articular surfaces of the involved joints remain reasonably intact.^{16,20,39,52,140,141} If joint deterioration is significant, resection arthroplasty, such as resection of the distal ulna (Darrach procedure) or proximal row carpectomy; arthrodesis; or implant arthroplasty, performed in conjunction with soft tissue repair or reconstruction, is a surgical option for advanced joint deterioration.^12,16,20

Some procedures are selected to relieve pain and others to minimize or delay further deformity. For example, if medical management of RA of the wrist does not adequately control synovitis, tenosynovectomy is performed to remove proliferated synovium from tendon sheaths and to prevent erosion or rupture of tendons before significant deformity and loss of active control of the wrist and fingers occur.¹⁴⁰ If rupture occurs, tendon repair or transfer can improve function of the hand and delay or prevent subluxation and dislocation of joints or fixed deformities.^52,54

Partial or complete arthrodesis of the wrist and arthrodesis of an individual joint of a digit, such as the CMC joint of the thumb, yield predictable and durable results. Fusion corrects deformity and gives the patient stability and relief of pain with only some compromise of function despite the loss of joint motion.^51,52,83 If fusion is inappropriate and pain-free functional mobility is necessary, implant arthroplasty—either interposition arthroplasty or total joint replacement—is an option. In many instances, a combination of joint and soft tissue procedures is indicated.^11,16,31 For the most part, however, arthroplasty is reserved for the patient who requires only low-demand use of the hand.

General goals. The goals of surgery and postoperative management of advanced arthritis and associated deformities of the wrist and hand include:^11,16,60,124 (1) relief of pain, (2) restoration of normal or sufficient function of the wrist and hand, (3) correction of instability or deformity; (4) restoration of ROM, and (5) improved strength of the wrist and fingers for functional grips and pinch.

A discussion of several types of arthroplasty and general guidelines for postoperative management follow. Information on surgical management and postoperative rehabilitation of tendon repairs and transfers associated with RA is then outlined. Given the complexity of hand rehabilitation, suggested phase-specific guidelines for exercise, founded on principles of tissue healing, must be individualized for each patient and determined by the patient's level of participation in the rehabilitation process and response to exercise.

Successful outcomes are contingent upon close communication among the surgeon, therapist, and patient or patient's family. An effective postoperative rehabilitation program combines early, supervised therapy with patient education and progresses to long-term self-management by the patient. Although rehabilitation is deemed essential after each of the surgical interventions covered in this section, postoperative protocols vary and have not been compared for each type of procedure, making it difficult to suggest that there is one best approach to postoperative management.

Wrist Arthroplasty

Although arthrodesis of the wrist continues to be the most common surgical intervention for late-stage arthritis of the wrist, arthroplasty has become an acceptable alternative, particularly for patients with arthritis and impaired mobility of other joints of the extremities. Although wrist arthrodesis has not been shown to limit upper extremity function in daily living activities in patients with posttraumatic arthritis of the wrist only, it is thought that loss of wrist motion may adversely affect functions, such as personal care, in patients with RA who also have impaired mobility of other upper extremity joints.¹³⁷ For these patients, wrist arthroplasty—total joint replacement or flexible implant (interposition) arthroplasty—is an option that provides relief of symptoms while retaining some wrist mobility.

Indications for Surgery

The following are common indications for arthroplasty of the wrist.^1,11,12,16

• Severe pain in the wrist region as the result of deterioration of the articular surfaces of the distal radius, carpals, and distal ulna from chronic arthritis (usually RA, but also OA and posttraumatic arthritis) that compromises hand and upper extremity function

• Deformity and marked limitation of wrist motion that cause muscle-tendon imbalances of the digits

• Subluxation or dislocation of the RC joint

• Appropriate procedure for low-demand upper extremity functional needs

• Appropriate procedure for patients with bilateral wrist involvement in which arthrodesis of both wrists would limit rather than improve overall function

• Also appropriate procedure for patients with significant stiffness of the ipsilateral shoulder, elbow, or finger joints in whom unilateral wrist arthrodesis would further limit, rather than improve, functional use of the upper extremity

CONTRAINDICATIONS Box 19.4 identifies some absolute and relative contraindications to wrist arthroplasty and arthroplasty of the joints of the fingers and thumb.^1,11,12,16

Procedures

Implant Design, Materials, and Fixation

Because partial or total arthrodesis of the wrist is often considered the procedure of choice (not just a salvage procedure) for patients with severe pain and instability of the wrist^51,83 and because resection arthroplasty of the distal radius and proximal row carpectomy³⁹ are also suitable options that relieve pain but retain some mobility of the wrist, the use of joint replacement surgery for patients with late-stage arthritis of the wrist has been somewhat limited.²⁰ Nevertheless, designs of implants and operative techniques for arthroplasty of the wrist have gradually evolved.

During the late 1960s, Swanson first used a one-piece, uncemented, double-stemmed, flexible ("hinged") implant made of silicone for the radiocarpal joint, primarily for use in patients with RA.¹²⁵ The prosthesis, which is inserted between the distal radius, through the capitate, and into the intramedullary canal of the third metacarpal (after a proximal row carpectomy), is designed to act as a dynamic spacer to maintain joint alignment during healing. Over time, the implant becomes encapsulated, forming a new fibrous capsule.^12,125 Although the procedure provides pain relief and some degree of stability and ROM (approximately a 60° arc of flexion/extension and a total of 10° of radial and ulnar deviation), its use has been associated with a high rate of failure as the result of excessive wear of the prosthesis or cystic changes in bone and eventual breakage or loosening of the prosthesis.^1,11,12,16 It also has been suggested that, as a silicone implant gradually wears (abrades), it may give rise to particulate synovitis (silicone synovitis).⁶¹ Design changes have been made to reinforce the silicone implant with bone-shielding devices (titanium grommets) to improve the long-term durability of the prosthesis.^11,12 Despite improvements, with the increased use of rigid implants for wrist arthroplasty, flexible interposition implant arthroplasty now plays a limited role, with its use reserved for the low-demand, older (> 60 years) patient with RA.¹⁶

Numerous designs of total wrist replacement arthroplasty (Fig. 19.9) have been developed and consistently refined over the past few decades, making arthroplasty available not only to patients with late-stage joint disease but also those with severe deformity and collapse of the wrist joint.^11,77 Total wrist arthroplasty typically involves inserting a two-piece system with elliptical (convex-concave) surfaces that are loosely constrained or nonconstrained. Components are made of rigid materials (cobalt-chrome or titanium and high-density polyethylene). The implants are sometimes porous-coated along the stems for bio-ingrowth,¹⁰⁰ and a combination of cement and screws is employed for additional fixation.^11,12,16 Most total wrist systems are designed to allow a combined 90° arc of flexion and extension.

Operative Overview

Total wrist arthroplasty requires a longitudinal incision along the dorsal aspect of the wrist in line with the third metacarpal.^11,12,16,72 Concomitant dorsal clearance (synovectomy of the wrist and tenosynovectomy of the extensor tendons) is often necessary. The retinaculum is incised and reflected, and the digital extensor tendons are retracted for access to the joint capsule.

The distal portions of the radius and ulna, some of the carpals, and a small portion of the proximal aspect of the third and often the second and fourth metacarpals are resected. The rigid, stemmed prosthetic components are then tightly fit into the reamed intramedullary canals of the necessary metacarpals and the distal radius.^11,52 With instability and subluxation of the radiocarpal joint, capsule and ligament reconstruction typically is performed to improve wrist stability. Soft tissue balancing is critical for satisfactory results.

After closure of the dorsal incision, the hand is placed in a long-arm or short-arm bulky compression dressing and elevated several days postoperatively to control edema.

Postoperative Management

Immobilization

After total wrist arthroplasty, the wrist is continuously immobilized in a neutral position for several days to 2 weeks. After the bulky, postoperative dressing is removed, the wrist and forearm are placed in a short-arm volar wrist splint with the wrist positioned in about 10° to 15° extension. The splint allows full finger ROM and opposition of the thumb. The time frame for removal of the splint for exercise varies from 1 to 4 weeks, depending on the extent of soft tissue reconstruction and bone stock qualtiy.^16,72,100

If a concomitant repair of the extensor tendons was performed, the immobilizer is fitted with outriggers that have elastic slings to hold the fingers in extension. Even after wrist exercises are initiated, the immobilizer is worn for protection between exercise sessions. A static resting splint is worn at night for 6 to 8 weeks postoperatively.⁵⁴

With a duration as short as 3 to 4 weeks or as long as 6 to 8 weeks, flexible implant arthroplasty generally requires a longer period of immobilization than total wrist replacement to allow time for encapsulation of the prosthetic spacer to occur.^122,138

Exercise Progression

As with arthroplasty of other large or small joints, the goals and progression of exercise during each successive phase of rehabilitation after wrist arthroplasty (both total wrist or interposition arthroplasties) are based on the stages of soft tissue healing. If concomitant extensor tendon repairs were also done, the guidelines and timeframe for exercise are adjusted and special precautions are taken, as discussed in a later section of the chapter on repair of extensor tendon ruptures in RA.

For protection of the wrist after arthroplasty, precautions, identified in Box 19.5, must be incorporated into postoperative exercises and functional activities during and after rehabilitation.^72,121

Exercise: Maximum and Moderate Protection Phases

The focus of rehabilitation during the maximum protection phase is to control pain and peripheral edema, protect the wrist, and prevent stiffness of the rest of the upper extremity. When the immobilizer can be removed for wrist exercises, protection of the wrist is still essential.

The emphasis during the moderate protection (controlled motion) phase, which typically begins about 4 to 8 weeks postoperatively, is to gradually restore active control and mobility of the digits, wrist, and forearm motion without jeopardizing wrist stability

Goals and interventions. The following goals and interventions should be considered before and after the wrist immobilizer can be removed for exercise.^{60,72,122,138}

• Maintain and later improve mobility of unoperated joints.

  • Begin active ROM exercises of the digits, elbow, and shoulder while the wrist is immobilized and the use of the hand is restricted.

  • If there is limitation of finger mobility preoperatively, around 6 weeks postoperatively, selectively use low-load, dynamic finger splint(s) during the day or gentle passive stretching initially with the wrist maintained in a neutral position to increase mobility for a sufficient level of hand function.

  • Grade II and possibly grade III joint mobilization techniques are appropriate if the joints of the digits are not inflamed.

• Restore control and mobility of the wrist.

  • Include active ROM, emphasizing wrist extension more than flexion, and tendon-gliding exercises with the wrist in neutral (see Fig. 19.17 A through E).

PRECAUTIONS: Postpone radial and ulnar deviation if wrist stability is questionable.⁶⁰ When performing radial and ulnar deviation, avoid wrist flexion with ulnar deviation (the position of wrist deformity).

• Regain use of wrist, finger, and thumb musculature.

  • Start with gentle setting exercises and progress to low-intensity, isometric resistance exercises of the wrist and finger musculature.

  • After total wrist arthroplasty, begin to use the hand for light (minimum-load) functional activities around 6 to 8 weeks.¹⁰⁰

  • After flexible implant arthroplasty, such use of the hand may be delayed until about 12 weeks postoperatively.¹²²

Exercise: Minimum Protection/Return to Function Phase

During the final phase of rehabilitation, which usually does not begin until 8 to 12 weeks postoperatively, regaining sufficient strength and muscular endurance of the entire upper extremity for appropriate functional activities is the priority.⁷² In the wrist, emphasize strengthening the wrist extensors rather than the wrist flexors. Patient education focuses on incorporating joint protection during functional activities (refer to Box 19.2). Use of a cock-up resting splint is advisable at night, particularly if a wrist flexion contracture persists. Although 15° of wrist extension is preferable for a strong functional grasp, the use of manual stretching procedures to increase wrist extension is not consistently advocated, as they may compromise wrist stability.¹²²

Goals and interventions. The following goals and interventions can be progressed as the extent of protection decreases.

• Regain functional strength of the hand and wrist.

  • Transition to low-intensity, dynamic resistance (about 1 lb) exercises of the hand and wrist.⁷²

  • Emphasize simulated functional movement patterns, such as various types of grasping activities, being certain to reinforce principles of joint protection.⁹⁵ If not previously initiated, begin to use the hand for light functional activities.

  • Twelve weeks after total wrist arthroplasty or flexible implant arthroplasty, the patient may use the hand for most low-load functional activities.^100,138

• Increase ROM of the wrist to a functional level.

  • Continue active ROM and gentle stretching exercises as dictated by the stability of the wrist.

  • Use low-load dynamic splinting of the wrist, emphasizing wrist extension to at least 15°.

  • In patients who exhibit significant postoperative stiffness of the wrist soon after surgery, stretching activities may be initiated earlier than during the minimum protection phase, possibly at 6 weeks postoperatively.¹³⁸

Metacarpophalangeal Implant Arthroplasty

Arthroplasty of the MCP joints of fingers (digits 2 to 5), combined with necessary reconstruction of soft tissues, is the most common surgical procedure performed to manage impaired function and progressive deformity as the result of late-stage RA of the hand.³¹ In patients with RA, hand function has been shown to improve over a 1-year period following MCP arthroplasty when combined with ongoing medical management. In contrast, the level of hand function does not deteriorate but does not improve over the same time period with ongoing medical management alone.²⁹ Arthroplasty is also an option for patients with idiopathic OA and posttraumatic arthritis of the MCP joints.^31,98,116

For MCP arthroplasty to be successful, a patient must have intact extensor digitorum communis tendons, or repair of these tendons must be performed. The two procedures may be staged, one prior to the other, or performed simultaneously as determined by the surgeon. Other procedures to balance soft tissues must also accompany MCP arthroplasty for improved hand function postoperatively.^31,75,116

If joints other than the MCP joints are involved, which is often the case in RA, surgeries are carefully sequenced. For example, if the wrist is involved, a radiolunate or total wrist arthrodesis for pain-free wrist stability in a functional position may be necessary prior to MCP arthroplasty. In contrast, a swan-neck deformity of a finger is managed with PIP fusion in 30° to 40° of flexion, but typically it is done after—not before—MCP arthroplasty.^31,121

Similar to wrist arthroplasty, the overall goals of this surgery and postoperative management are to relieve pain, correct alignment of the fingers, improve active hand opening and grasp, and improve the cosmetic appearance of the hand.^75,121

Indications for Surgery

The following are common indications for arthroplasty of the MCP joint(s).^12,31,75,116

• Pain at the MCP joint(s) of the hand and diminished hand function as the result of deterioration of the articular surfaces, usually because of RA but sometimes as the result of OA or posttraumatic arthritis

• Instability, often coupled with volar subluxation, and deformity (flexion and ulnar drift) of the MCP joint(s) that cannot be corrected with soft tissue releases and reconstruction alone

• Stiffness and decreased active ROM of the MCP joints, often associated with a deficient extensor mechanism, causing inability to open the hand to grasp large objects

• Poor appearance of the hand as the result of deformity

Procedures

MCP joint arthroplasty is designed to provide a balance of stability and mobility to the MCP joints for patients with late-stage arthritis. Several designs using different materials and methods of fixation have been developed over the past few decades. Swanson developed a one-piece, flexible, double-stemmed prosthesis made of silicone (Fig. 19.10) that is uncemented; it serves as a dynamic spacer and an internal joint mold, as it becomes encapsulated during the healing process.^{12,15,55,75,84} The implant maintains internal alignment of the joint during healing and allows early postoperative joint motion. As with radiocarpal flexible implants, the MCP silicone implant sometimes is reinforced with circumferential titanium grommets to minimize long-term component wear or fracture and the possibility of silicone synovitis.¹²⁴ Although the original Swanson implant has undergone some minor design changes, it has been a highly reliable design and remains the most widely used MCP implant for patients with RA.^31,124 The Swanson implant also has been used successfully in patients with OA⁹⁸ and posttraumatic arthritis.³¹

Other silicone implants have been developed as alternatives to the Swanson implant. One such design is the Neuflex^® implant (see Fig. 19.10), which is preformed in 30° of flexion to replicate the position of the MCP joints when the hand is at rest. The design is intended to improve ROM.^41,75

As an alternative to flexible implant arthroplasty, two-component, convex-concave, surface replacements made of either metal and high-density polyethylene or pyrolytic carbon (pyrocarbon) with highly polished, articular surfaces also have been developed.^31,44 The metal-plastic surface replacements typically use cement fixation, but the pyrocarbon implants rely exclusively on press-fit, noncemented fixation because of the nature of the material.^30,31

Unlike the one-piece flexible implants, the two-component NCP joint replacements have little to no inherent stability and therefore must rely on intact or repairable collateral ligaments for joint stability. Consequently, the two-component designs are used infrequently for patients with RA who typically have poor quality soft tissues as the result of long-standing inflammation and deformity, making it difficult to repair the collateral ligaments. Rather, these designs are reserved for patients with OA or posttraumatic arthritis whose collateral ligaments are either intact or can be repaired.⁴⁴ One resource suggests that a silicone implant is indicated if there is an extensor lag (lack of active extension) of the MCP joints > 60° and ulnar deviation > 45°.³¹

MCP arthroplasty and related soft tissue balancing involve the following procedures.^31,75,98 The involved MCP joints are approached by either a single, transverse incision over the dorsal aspect of the metacarpal heads or by double, longitudinal incisions made between the index and middle fingers and the ring and little fingers. The joint capsule is exposed by carefully separating the extensor tendons, which are often ulnarly displaced, from the underlying capsule and longitudinally incising the extensor hood. The tendons are retracted; the ulnar and possibly the radial collateral ligaments, if intact, are reflected from the head of each metacarpal; and the dorsal aspect of the capsule is incised (capsulotomy). Every effort is made to preserve the radial collateral ligaments. A synovectomy is performed if necessary. If a significant flexion contracture exists, the volar aspect of each capsule may also be incised to allow greater extension of the MCP joints.

The heads (distal aspect) of the metacarpals and proximal aspect of the first phalanges of the involved joints are excised, and the intramedullary canals of the metacarpals and proximal phalanges are widened to accept the prosthetic implants. After insertion of the implants, the ROM of the replaced joints is checked. The joint capsule, radial collateral ligament (if preserved), and extensor mechanism of each digit are repaired. The wound is then closed, and a bulky compression dressing and volar hand and forearm splint are placed on the hand. The hand is elevated to control edema.

Postoperative Management

As with arthroplasty of the wrist or other joints of the digits, the postoperative rehabilitation program is founded on the principles of soft tissue healing and includes phase-specific goals and interventions, including the use of dynamic and/or static splinting and a supervised home exercise program.

General postoperative guidelines from a number of resources for a progression of exercises combined with the use of splints to maintain alignment and protect soft tissues as they heal are summarized in this section.^{14,21,31,124,130,138} These guidelines must be individualized, based on the type of arthroplasty and soft tissue procedures performed and each patient's response. Ongoing patient education and close communication with the surgeon are essential for effective outcomes. Postoperative rehabilitation continues for 3 to 6 months.

Initially, the wrist and hand are continuously immobilized in the bulky compression dressing and volar splint applied at the end of surgery, with the wrist positioned in neutral, the MCP joints in full extension and either neutral or slight radial deviation (opposite the position of deformity), and the distal joints (PIP and DIP) in slight flexion.^31,72,124 In some instances, the splint extends only to the level of the PIP joints.⁹⁸ The bulky dressing is later replaced with a light compression dressing.

Continuous immobilization is not lengthy but varies with the type of arthroplasty, the type and quality of the soft tissue repairs, and the stability of the reconstructed joints. If only an MCP implant was performed, the hand remains immobilized for only a few days. If, in addition to the MCP arthroplasty, ruptured extensor tendons also were repaired or transferred, the hand remains immobilized longer to protect the tendons.⁵⁴

Dynamic splinting. When the compression dressing is removed, the hand is placed in a dynamic MCP extension splint with an outrigger (Fig. 19.11). The splint is worn to protect healing structures, maintain alignment (to prevent recurrent flexion and ulnar drift deformities at the MCP joints), and control and guide the range and plane of motion during exercises as soft tissues heal.^{14,29,124,130,135}

The dynamic splint holds the wrist in about 10° to 15° of extension and the MCP joints in full extension and slight radial deviation as well as supination of the index finger, but it does not control motion in the IP joints. Slings under the proximal phalanx of each finger with rubber bands attached to the outrigger of the splint hold the MCP joints in extension when the hand is at rest but still allow active flexion of the MCP joints within a functional range. The patient wears the dynamic splint throughout the day, including exercise sessions for about 6 weeks.²⁹

In some instances, a dynamic MCP flexion splint may be indicated at 2 to 3 weeks and worn intermittently or alternately during the day with the dynamic extension splint if sufficient MCP flexion has not yet been attained, particularly in digits 3, 4, and 5.^{12,14,72,124,130,135,138} By 6 weeks—but sometimes as late as 12 weeks postoperatively—dynamic splinting is gradually discontinued unless an active extensor lag or a flexion or extension contracture of the MCP joints persists.^{14,29,31,72,124,130,135}

Static splinting. If a dynamic splint is worn during the day, the patient wears a volar static (resting splint), which holds the wrist in 15° of extension and the fingers in full or almost full extension, at night. A block along the ulnar border of the splint prevents ulnar deviation of the fingers. If a flexion contracture or active extensor lag of the MCP joints is present, night splinting is often continued for 3 to 4 months or as long as a year.^{14,72,130,135}

Although dynamic splinting is widely used after MCP arthroplasty, another option is the alternating use of two static splints, one that holds all of the finger joints in extension and another that holds the MCP joints in flexion and the PIP and DIP joints in almost full extension.²¹ Each splint is worn for 24 hours at a time. During the day, the splint is removed frequently for gentle assisted ROM exercises. Some clinicians suggest that static splints are as effective as dynamic splints; easier and less expensive to fabricate, modify, and self apply; and less cumbersome to wear, because there is no need for the high-profile outrigger and rubber band suspension slings used in a dynamic splint.²¹

Protected motion in a dynamic splint or out of a static splint is initiated as early as 3 to 5 days or as late as 10 to 14 days postoperatively when the bulky compression dressing is removed and splints have been fabricated.^{14,21,31,72,124,130} Time frames vary with the type of procedures performed, the underlying pathology, and the stability of the joint. Even after the bulky dressing is removed, exercise may be delayed for several weeks for a patient with poor quality soft tissue repairs and potential joint instability or delayed wound healing.

With OA or posttraumatic arthritis, the involved MCP joints usually are stable postoperatively. Therefore, MCP exercises typically are begun earlier and progressed more rapidly in these patients than is permissible for patients with RA, whose joints tend to be less stable as the result of longstanding tissue inflammation and deformities.⁹⁸

Swanson and associates¹²⁴ proposed that a goal of exercise for the patient with RA is to achieve full or almost full active extension and about 45° and 60° of flexion of the MCP joints of the index and middle fingers respectively and 70° in the ring and little fingers. Greater ROM may be possible for the patient with OA, particularly in the index and middle fingers. In addition to improving the overall excursion of each reconstructed joint, another goal of exercise is to elevate the arc of active MCP motion to a more functional range—that is, to decrease or eliminate the active extension deficit (extensor lag) while increasing flexion to improve hand opening and grasp.^21,55

For the first 4 to 6 weeks, the patient performs only assisted or active exercises and is not allowed to use the hand for functional activities. The focus of management is to protect healing structures while applying safe levels of stress to soft tissues to influence organized scar tissue formation and prevent adhesions through protected motion within limited ranges. Early motion also assists in controlling or reducing postoperative peripheral edema.

Goals and interventions. The following goals and exercises are emphasized during the maximum protection phase.^{14,21,72,130,135,138}

• Maintain mobility of the shoulder, elbow, and forearm.

  • Perform active shoulder, elbow, and forearm ROM. This is particularly important for patients whose RA is affecting multiple joints of the body.

• Improve functional ROM of the fingers and maintain gliding of tendons within their sheaths.

  • Initiate active PIP and DIP flexion and extension, with the MCP joints held in extension by the dynamic splint. If static splinting is used, remove the splint and teach the patient to manually stabilize the MCP joints in extension.

  • Perform active, pain-free MCP flexion initially with the IP joints in extension followed by extension of the MCP joints assisted manually or by the dynamic splint. The dynamic splint usually allows no more than 60° to 70° of MCP flexion.^72,130 Manually stabilize the IP joints in extension or temporarily splint them in extension with tape and tongue depressors during exercise sessions, so the lumbricals act to flex the MCP joints. If multiple MCP joints have been replaced, which is usually the case in patients with RA, have the patient exercise one MCP joint at a time to be certain that flexion and extension increase in each of the MCP joints. If the patient is having difficulty actively flexing the MCP joint of the little finger, the fourth and fifth digits can be taped together some of the time to allow the ring finger to assist flexion of the little finger.^14,21,72,130

  • If it is permissible to remove the splint for exercise, teach the patient to perform active radial deviation of the MCP joints by placing the open hand palm-down on a table, stabilizing the dorsum of the hand with the opposite hand, and sliding ("walking") the fingers toward the thumb.

  • Include active composite finger flexion and opposition of the thumb to each digit, emphasizing pad-to-pad pinch rather than lateral pinch.

PRECAUTIONS: During exercise, avoid lateral pressure of the thumb against the digits, which could contribute to recurrence of an ulnar deviation deformity of the fingers. Carefully observe the incision during MCP flexion, being certain to avoid excessive tension on the skin and delay wound closure.

• Prevent adhesions along the healed incision.

  • Perform gentle mobilization of the scar when sutures have been removed.

The emphasis of the moderate protection phase, which begins at about 3 to 4 weeks or as late as 6 weeks postoperatively, is to achieve full active extension of the MCP joints (no extensor lag) and continue to increase active MCP flexion as early as possible during this phase of rehabilitation for functional use of the hand.^{14,124,130,135}

At the beginning of this phase or by 6 weeks, removal of the dynamic extension splint for exercise may be permissible if the MCP joints are stable. Very low-intensity strengthening exercises and light use of the hand for ADL also are initiated around 4 to 6 weeks. If the joints are stable and well aligned and there is sufficient MCP flexion and no active extension deficit, daytime splinting during general activity is gradually discontinued starting around 6 weeks or as late as 12 weeks if joint stability is in question.^14,21,72

During the minimum protection phase, which begins around 8 to 12 weeks postoperatively, progressive strengthening of the wrist and hand musculature and increasing use of the hand for functional activities while reinforcing principles of joint protection are emphasized. In most instances, a patient is allowed full use of the hand for light to moderate functional tasks by 12 weeks postoperatively.

Goals and interventions. During the moderate and minimum protection phases, goals include the following.^{14,21,31,72,124,130,135}

• Continue to increase ROM and active control of the MCP joints.

  • Have the patient continue active flexion exercises in the dynamic splint or with the static splint removed and even after daytime splinting is discontinued. Add gentle passive stretching, one finger at a time, to increase flexion.

  • Emphasize active MCP extension with the wrist in neutral and the IP joints flexed (the intrinsic minus/hook fist position of the hand) to reinforce the action of the extensor digitorum communis (EDC) muscle and minimize influence of the intrinsic finger extensors. This movement also promotes gliding of the extrinsic extensors in the tendon sheaths.

  • Reinforce end-range MCP extension by maintaining the extended position briefly with each repetition.

• Restore ROM of the wrist.

  • When the dynamic splint can be removed during exercise, initiate active ROM of the wrist, emphasizing wrist extension. Be sure the fingers are relaxed during wrist motions.

• Improve functional strength of the hand and wrist.

  • Have the patient begin isometric flexion and extension against submaximal manual resistance or a solid object at 6 to 8 weeks postoperatively. Then transition to resisted dynamic finger flexion and extension using a variety of exercise devices, such as a small spring-loaded hand exerciser or exercise putty.

  • Include resisted radial deviation of the digits. For example, have the patient place the hand on a table palm-down and stabilize the dorsum of the involved hand with the opposite hand. Abduct the index finger against the resistance of a rubber band or push against a coffee cup and slide it across the table.¹⁴

• Regain use of the hand for functional activities while protecting the operated joints to prevent recurrence of deformity.

  • Reinforce principles of joint protection and energy conservation through patient education (see Box 19.2). Emphasize avoidance of stresses on the fingers in an ulnar direction.

  • Perform simulated functional grasping activities, beginning with light prehension activities. Use the hand for light to moderate functional activities by 8 to 12 weeks postoperatively.

  • Modify activities of daily living that could contribute to deforming stresses on the MCP or other involved joints.^72,94,95 Consider use of a commercially fabricated, hand-based, digital alignment splint made of neoprene during heavier, more stressful activities.¹⁴

Proximal Interphalangeal Implant Arthroplasty

There are a number of joint and soft tissue procedures for managing arthritis and associated deformities of the PIP joints. They include soft tissue release and reconstruction for swan-neck and boutonnière deformities¹²¹ and implant arthroplasty or arthrodesis when there is significant destruction of the articular surfaces.^1,69,123,127 PIP arthroplasty is used more frequently for late-stage OA or posttraumatic arthritis than for RA, but may or may not be preferable to arthrodesis to improve functional use of the hand.

In the ulnar digits, where mobility of the PIP joints is particularly important for functional grasp, arthroplasty may be the procedure of choice.⁵² However, in the index finger, where stability of the PIP joint is a necessity for many functional tasks, arthrodesis is often preferable.^2,12,124 If the MCP and PIP joints are involved, as is often the case in patients with RA, the MCP joint is usually replaced, but the PIP joint deformity (usually a swan-neck deformity) is corrected by soft tissue reconstruction¹²⁴ or fusion.²

Indications for Surgery

In general, PIP implant arthroplasty is indicated for patients with isolated PIP involvement, particularly those who are free of MCP joint disease. Implant arthroplasty of contiguous joints (both the MCP and PIP joints) is not recommended.^12,123,124 The following are commonly accepted indications for PIP joint arthroplasty.^{2,12,52,53,72,123}

• PIP joint pain and destruction of the articular surfaces (with or without joint subluxation) secondary to OA or posttraumatic arthritis (less frequently indicated for RA) when nonoperative management has been unsuccessful

• Loss of hand function as the result of joint stiffness, deformity, and decreased ROM that cannot be corrected with soft tissue reconstruction and/or nonoperative treatment

• Only occasionally for isolated boutonnière deformity or swan-neck deformity if fusion is not a viable option

NOTE: Necessary prerequisites for PIP arthroplasty include adequate bone stock, intact neurovascular system, and functioning flexor/extensor mechanisms.^12,53,72,123

Procedure

The type of arthroplasty of the PIP joint selected by the surgeon depends on the underlying pathology, the extent of associated impairments and deformities, and the experience of the surgeon. As with MCP arthroplasty, there are two categories of implant arthroplasty for the PIP joints: a one-piece, flexible silicone joint spacer^12,123,127 or a two-component (nonarticulated), minimally constrained, surface (total joint) replacement system made of metal and plastic or pyrolytic carbon.^{2,69,121,127,139} The components of a metal-plastic surface replacement are secured by cement fixation. In contrast, the pyrolytic carbon designs involve noncemented, press-fit fixation.

The silicone implant, designed by Swanson during the 1960s, remains in use today.^123,124 Two-piece, surface replacement systems, first developed during the late 1970s, have undergone many design changes and improvements.^2,12,127 A surface replacement design affords greater joint mobility than the one-piece silicone design but provides no inherent stability. Therefore, when PIP arthroplasty is deemed appropriate for patients with RA, who typically have compromised joint stability as the result of damage to periarticular soft tissues secondary to chronic synovitis, a one-piece silicone implant tends to be used to provide some stability to the joint. In contrast, surface replacement arthroplasty is used almost exclusively in patients with OA or posttraumatic arthritis, because the collateral ligaments usually are intact or repairable.

A curved, longitudinal incision is made usually along the dorsal aspect of the PIP joint. Occasionally, a volar (palmar) or lateral approach is used. With a dorsal approach, either a central slip-sparing technique (which leaves the central tendon intact) or a central slip-splinting technique (where the central tendon is incised longitudinally) is used. The latter approach is selected when there is significant joint deformity. Table 19.3 provides an overview of which soft tissues are released, repaired, and require protection during the postoperative program and which structures remain intact during the operative procedure.^2,10,53,69

Portions of the head of the proximal phalanx and the base of the middle phalanx are resected. The intramedullary canals of the proximal and middle phalanges are reamed and prepared for the prosthetic implant(s), which is then inserted.

If necessary, the volar plate is released for a flexion contracture, and the extensor tendon mechanism (if split during the approach) is repaired. Then the joint capsule is repaired; the wound closed; and a bulky compression dressing placed on the hand. The hand is supported in a volar splint, which includes the forearm, and elevated in a sling above the level of the shoulder to minimize edema.

Postoperative Management

When the surgical dressing is removed, a custom volar resting splint and possibly a dynamic extension splint with an outrigger are fabricated. These are hand-based splints that leave the wrist free but maintain the MCP joints in flexion.^{2,12,53,124,131} An extension stop also may be incorporated into the splint to limit PIP hyperextension.¹³⁹ The position of PIP joint immobilization varies with the type of preoperative deformity that existed and the type of soft tissue reconstruction performed. Recommended positions of the immobilization are summarized in Table 19.4.^2,12,124,131

The duration of immobilization varies with the type of arthroplasty, whether extensor tendon or collateral ligament reconstruction of the fingers was part of the procedure, and the surgeon's philosophy.^{2,12,52,53,72,124,131} Protective splinting with frequent sessions of assisted or active exercises continues during the day for at least 6 to 8 weeks postoperatively and is gradually eliminated by 12 weeks. Night splinting may continue for 3 to 6 months or up to a year to protect the repaired joint(s).

The sequence of exercises after PIP arthroplasty emphasizes early but protected motion of the operated and adjacent joints. The time frame for initiating PIP exercises in the dynamic splint or out of the static splint varies from a few days^{2,52,53,72,139} to 10 to 14 days¹³¹ postoperatively based on the type and extent of impairments of the fingers preoperatively and the type of prosthetic implant and reconstructive procedures used. For example, after a central slip-sparing approach (extensor mechanism remains intact), ROM exercises are initiated as soon as the bulky dressing has been removed (1 to 3 days postoperatively). After a central slip-splitting approach in a joint with no associated swan-neck or boutonnière deformity, ROM exercises are begun several days to a week to 10 days later.

The goals of exercise during each of the following phases of rehabilitation after PIP arthroplasty are similar to those already detailed in this chapter for rehabilitation after MCP arthroplasty. Only guidelines and precautions unique to PIP arthroplasty or procedures for associated correction of specific soft tissue deformities of the PIP joints are addressed in this section.

The primary goals of the maximum and moderate protection phases of rehabilitation after PIP arthroplasty are to control peripheral edema and restore functional mobility of the operated joint(s) without compromising the repair or reconstruction of soft tissues.

In most instances, the emphasis is to regain full or nearly full active PIP extension while gradually increasing PIP flexion by 10° to 15° per week.² It is desirable to achieve approximately 70° of PIP flexion in the ring and little fingers, 60° in the middle finger, and at least 45° in the index finger with full or almost full PIP extension by the end of the moderate protection phase (by 6 to 8 weeks postoperatively).¹⁷ Dynamic flexion splinting may be instituted if adequate flexion is not achieved with exercise alone.

Goals and interventions. The following goals and interventions are recommended as general guidelines during the first 6 to 8 weeks after surgery. Detailed protocols describing use of splints and progression of exercises following different types of PIP arthroplasty are described in several resources.^{2,12,52,53,72,124,131,139}

• Maintain mobility of the wrist, MCP and DIP joints.

  • Immediately after surgery, initiate active ROM of all joints not restricted by the bulky dressing.

• Restore ROM of the operated joints.

  • Begin active PIP flexion in the dynamic splint or with the static splint removed and assisted flexion and extension of each PIP joint. Stabilize the MCP and DIP joints in neutral to direct motion to the PIP joint (promotes joint mobility and tendon gliding).

  • If a boutonnière deformity was corrected (which requires reconstruction of the extensor mechanism), follow the guidelines and precautions described in Box 19.6.^121,131

  • If a swan-neck deformity was corrected, follow the guidelines and precautions noted in Box 19.7.^52,121,131 A central, slip-splitting approach is necessary for correcting a swan-neck deformity to allow the tension on the extensor mechanism to be adjusted and greater excursion of the PIP joint into flexion.

PRECAUTION: During ROM exercises, it is essential to avoid lateral and rotational stresses to the operated joints that could compromise the integrity of the collateral ligaments and joint stability.

The primary goal of the minimum protection phase shifts from restoration of functional ROM to improving strength in the hand and wrist and gradually incorporating safe but progressive use of the hand into functional activities of daily living. This transition occurs around 6 to 8 weeks—or as late as 12 weeks—postoperatively. The status of the soft tissue repairs, particularly the extensor tendons, determines how early resisted exercises are initiated. For optimal results, rehabilitation may need to continue (through adherence to a home program) for 6 months or longer postoperatively.

As with MCP arthroplasty, low-intensity strengthening exercises can be performed with equipment specifically designed for hand rehabilitation, such as exercise putty, or through graded functional activities that involve resisted movements. Principles of joint protection (see Box 19.2) are integrated into daily living through patient education, with attention to continued avoidance of lateral stresses to the PIP joints.

Carpometacarpal Arthroplasty of the Thumb

Arthritis of the CMC joint, also called the trapeziometacarpal joint, of the thumb, leads to pain and stiffness and occurs with advancing age in women more often than men.⁸⁷ When this joint is involved, a patient has difficulty with forceful grasp and pinch and wringing motions. If a patient remains symptomatic after a period of conservative management, including anti-inflammatory medications, splinting, activity modification, and exercise, arthrodesis or one of several types of arthroplasty may be appropriate for relief of symptoms and improved function.³²

Indications for Surgery

The following are common indications for CMC arthroplasty of the thumb.^{12,23,32,116,129}

• Disabling pain at the base of the thumb, specifically the CMC joint, as the result of OA, posttraumatic arthritis, or RA. However, most CMC arthroplasties are performed for degenerative joint diseases and less often for synovium-based diseases.

• Dorsal-radial instability (subluxation or dislocation) of the first metacarpal on the trapezium, leading to a hyperextension deformity at the MCP joint of the thumb.

• Stiffness and limited ROM (often an adduction contracture) of the thumb.

• Decreased pinch and grip strength because of CMC pain or subluxation.

• Arthrodesis of the CMC joint is inappropriate.

Procedures

The type of procedure selected depends on the degree of ligament laxity, the extent of destruction of the articular surfaces, the underlying pathology, and the expected demands that will be placed on the hands postoperatively.^32,116 Arthrodesis, rather than arthroplasty, is an option for patients who use the hand for high-demand occupational activities. However, for the patient whose activities place less stress on the hand, there are several soft tissue and boney procedures that relieve pain and restore joint stability, but preserve functional mobility at the base of the thumb.^32,87 Retaining some CMC joint mobility is particularly important for the patient with RA, who typically has loss of mobility of other joints of the hand and wrist.¹²⁹

Procedures for CMC arthroplasty fall into three broad categories: (1) ligament reconstruction; (2) trapezial resection/tendon interposition or suspension arthroplasty (usually with ligament reconstruction); and (3) surface replacement arthroplasty (resurfacing or total joint surface replacement) of the CMC joint with prosthetic components that are cemented in place.^32,134 Among these procedures, ligament reconstruction alone is used when there is pain and instability but little to no loss of articular cartilage.³² One of the many variations of trapezial resection/tendon interposition arthroplasty is by far the most widely used approach to treatment when there is joint subluxation and loss of the joint space due to deterioration of articular cartilage.^{10,12,23,32,52,67,116,129} Trapezial resection, combined with ligament reconstruction but without tendon interposition, also has been shown to be an effective surgical approach to treatment.⁶⁸

Surface replacement arthroplasty is an alternative to trapezial resection/tendon interposition arthroplasty for a select few patients with CMC OA, who require improved pinch but do not need to use the hand for high-load, high-impact activities.^12,32,52 Surface replacement arthroplasty involves either resurfacing one articular surface or replacing the surfaces of the trapezium and metacarpal (also known as a total joint surface replacement) with a two-component, saddle-shaped rigid implant that is cemented in place.^32,134 A patient must have good quality bone stock to be a candidate for surface replacement arthroplasty. If bone stock is poor, as often occurs in RA, cement fixation of the prosthetic components usually is unsuccessful. Although considered a viable option in the past,³⁴ silicone implant arthroplasty now is used infrequently because of the problems of joint dislocation and silicone wear.^10,32

Because instability (hyperextension) and arthritis of the MCP joint are frequently associated with CMC arthritis, concomitant stabilization with a temporary K-wire or arthrodesis of the MCP joint is performed in addition to reconstruction of the CMC joint.^32,129

Tendon interposition arthroplasty. For a tendon interposition arthroplasty, a dorsal incision is made at the base of the thumb, with careful attention paid to protecting the branches of the superficial radial nerve. The capsule is approached through the extensor tendons and incised longitudinally. All or a portion of the trapezium is resected (trapeziectomy), as is a small portion of the base of the first metacarpal. A tendon graft is harvested from a portion of the flexor carpi radialis, abductor pollicis longus, or palmaris longus and inserted into the trapezial space to act as a soft tissue spacer.^{10,12,23,32,52,67,116,129} The anterior oblique ligament may also be reconstructed with a portion of the tendon graft; if not used for the tendon graft, the abductor pollicis longus may be imbricated or advanced to enhance joint stability and function of the abductor postoperatively.⁵² The capsule and adjacent soft tissues are then repaired, and the wound is closed.

Surface replacement arthroplasty. For a surface replacement arthroplasty, a dorsal approach is also used to reach the capsule through a longitudinal incision between the abductor pollicis longus and the extensor pollicis brevis. For a total joint surface replacement, a volar approach may be used.³² With a two-component design, after the capsule has been split longitudinally, the distal portion of the trapezium and the base of the first metacarpal are resected. The trapezium and the intramedullary canal of the metacarpal are prepared, and the prosthetic components are inserted and cemented in place. The capsule is repaired, and as with soft tissue interposition arthroplasty, the abductor pollicis longus may be advanced to enhance joint stability. Joint stability and ROM are assessed prior to closure and application of a bulky compression dressing.

Postoperative Management

The overall goal of rehabilitation following CMC arthroplasty is to attain sufficient pain-free mobility of the thumb for functional activities while maintaining joint stability for strong pinch and grasp. It may take up to a year after surgery for a patient to achieve optimal results.

With all procedures, the thumb and hand are immobilized postoperatively in a bulky compression dressing and elevated for several days to a week to control edema.

After the postoperative dressing is removed, the hand is placed in a static, forearm-based thumb spica cast, which is later replaced with a removable splint, with the CMC joint immobilized in abduction (40° to 60°), the MCP joint in slight flexion, and the wrist in neutral to slight extension.^{12,32,52,87,104,134} The IP joint of the thumb and the fingers are left free.

The length of time the CMC joint is continuously immobilized depends on the surgery. The time frame varies from just 1 to 2 weeks after total surface replacement arthroplasty^32,134 to 3 to 5 weeks after ligament reconstruction/tendon interposition arthroplasty or resurfacing arthroplasty with prosthetic implants.^{12,32,52,87,104,129,138}

When ROM exercises are permitted after surgery, the splint is removed during the day for frequent exercise sessions. From 8 to 12 weeks, as the patient uses the hand for functional activities, daytime splinting is gradually discontinued. Use of a night splint to stabilize the thumb continues for 8 to 12 weeks or until the joint is stable and essentially pain-free.^32,104,129

Progression of exercises varies with the type of arthroplasty. Guidelines presented in this section are for ligament reconstruction/tendon interposition arthroplasty, still the most common form of CMC arthroplasty. Management guidelines unique to total surface replacement arthroplasty also are noted. Precautions after CMC arthroplasty are summarized in Box 19.8.^32,87,104

The focus of the first 6 weeks of rehabilitation is to control pain and edema, maintain ROM in nonimmobilized joints, and initiate protected motion of the CMC joint when it is permissible to remove the thumb spica splint for exercise.^{32,87,104,129}

Goals and interventions. The following are suggested goals and exercise interventions for the first 6 weeks after surgery.

• Maintain mobility of the fingers and IP joint of the thumb.

  • During the period of continuous immobilization of the wrist and CMC and MCP joints of the thumb, have the patient perform active ROM of the fingers and the IP joint of the thumb.

• Initiate protected mobility of the thumb and wrist.

  • When permissible, begin active, controlled ROM of the thumb within protected ranges and the wrist.

  • After tendon interposition arthroplasty, protected ROM is not initiated until about 3 to 6 weeks after surgery to allow time for the reconstructed soft tissues to heal adequately.^{32,87,104,129,138}

  • After total surface replacement arthroplasty, ROM may be initiated at about 1 week postoperatively because of the inherent stability of the cemented implants prosthesis.³² When it is permissible to remove the splint for exercise, begin active wrist ROM in all directions and CMC ROM with active abduction and extension; then add opposition and circumduction. Also include active MCP flexion and extension, being certain to stabilize the CMC joint.

While continuing to regain ROM, the focus of rehabilitation during the intermediate and final phases of rehabilitation gradually shifts to developing grip and pinch strength for functional tasks.

Goals and interventions. Consider the following goals and interventions.

• Re-establish functional mobility of the hand and wrist.

  • Continue active ROM exercises using gradually increasing ranges.

  • At about 8 weeks, begin gentle self-stretching exercises or dynamic splinting if limitations in functional ROM persist.

• Regain strength and functional use of the hand and wrist.

  • At about 8 weeks postoperatively, initiate isometric exercises against light resistance, emphasizing abduction and extension.

  • If the CMC joint is stable and pain-free, progress to dynamic resistance exercises to regain pinch and grasp strength.

  • Between 8 and 12 weeks, remove the splint when using the hand for light ADL, such as buttoning and unbuttoning.^87,129,138

  • Incorporate principles of joint protection during strengthening exercises and ADL.

  • Continue to increase use of the hand for light to moderate ADL over the next 4 to 6 weeks. A patient typically can return to light-duty work by 3 to 4 months and can resume most functional activities by 4 to 6 months.

Tendon Rupture Associated with RA: Surgical and Postoperative Management

Background and Indications for Surgery

Ruptures of tendons of the hand are common in patients with chronic tenosynovitis associated with RA. The site of the rupture may be in the wrist or the hand. When a tendon ruptures, there is a sudden loss of active control of one or more of the digits. Rupture of a single or multiple tendons is usually painless and occurs during unremarkable use of the hand.^10,52,54 Such ruptures are evidence of severely diseased tendons.

The extensor tendons are affected far more frequently than the flexor tendons. In order of frequency, extensor tendons that most often rupture are the common extensor tendons to the small and ring fingers and the extensor pollicis longus (EPL). The most common flexor tendon to rupture is the flexor pollicis longus (FPL).^52,54,140

The causes of rupture include infiltration of proliferative synovium in the tendon sheaths and into tendons, which subsequently weakens the affected tendon; abrasion and fraying of a tendon as it moves over a boney prominence roughened or eroded by synovitis; periodic use of local steroid injections over time; or ischemic necrosis caused by direct pressure from hypertrophic synovium, particularly at the dorsal retinaculum, that compromises blood supply to a tendon. Common sites of abrasion that affect the extensors are the distal ulna, Lister's tubercle, and the volar aspect of the scaphoid where it contacts the flexor tendons.^10,52,54,140

The indication for surgery is loss of function of the hand. Rupture of a single tendon, such as the extensor digiti minimi, may not impair a patient's function, whereas rupture of multiple tendons simultaneously or over a period of time may cause significant limitations of function and disability.

Procedures

The surgical procedures available for treatment of tendon ruptures in RA vary depending on which tendon(s) has ruptured, the number of ruptured tendons, the location of the rupture, the condition of the tendon at the site of rupture, and the quality of the remaining intact tendons of the hand. Options include^10,52,54,140:

• Tendon transfer. A tendon is removed from its normal distal attachment and attached at another site. For example, the extensor indicis proprius (EIP) can be transferred if the EPL has ruptured. A flexor tendon can also be transferred to the dorsal surface of the hand to act as an extensor if multiple extensor tendons have ruptured.

• Tendon graft reconstruction. A portion of another tendon that acts as a "bridge" is inserted between and sutured to the two ends of the ruptured tendon. The palmaris longus tendon is often selected as the donor tendon. A wrist extensor tendon may be selected if a wrist arthrodesis is performed at the time of the tendon reconstruction.

• Tendon anastomosis (side-to-side tenorrhaphy). The ruptured tendon is sutured to an adjacent intact tendon. This is a common option at the wrist for the finger extensor tendons.¹⁴⁰

• Direct end-to-end repair. The two ends of the ruptured tendon are re-opposed and sutured together. This option is used only occasionally, because the ends of the ruptured tendons in patients with RA usually are frayed. Therefore, a considerable portion of the frayed tendon(s) must be resected, which shortens the tendon, making it difficult to suture end-to-end.

Concomitant procedures in the rheumatoid hand include tenosynovectomy, removal of osteophytes from boney prominences, and ligament reconstruction or arthrodesis for instability. If late-stage MCP joint disease also is present and passive extension of the MCP joints is significantly limited, arthroplasty of the involved joints may be indicated as well, either simultaneously with the tendon procedure or during two separate operations as determined by the surgeon. Without adequate joint mobility, the transferred or reconstructed extensor tendons become adherent, resulting in a poor outcome.

Postoperative Management

The guidelines described in this section apply only to management of tendon transfer, reconstruction, or repair of extensor tendons in the rheumatoid hand. As mentioned previously, rupture of extensor tendons occurs far more frequently than flexor tendon rupture. As with postoperative management for other surgeries described in this chapter, pain and edema control and exercises for the nonoperated extremities are always essential components of rehabilitation.

Tendon transfers and reconstruction are delicate procedures requiring ongoing communication between the therapist and surgeon and active involvement of the patient in the postoperative program. Therefore, patient education is woven into every phase of rehabilitation.

A bulky compression dressing is applied to the hand and wrist at the close of extensor tendon surgery to control edema. The surgical compression dressing is removed after several days, and the wrist and hand are then immobilized in a volar splint. A forearm-based, resting splint holds the wrist and digits in a position that minimizes stress to the transferred or reconstructed tendon(s).

For example, after side-to-side finger extensor transfer or extensor tendon reconstruction, the wrist and all fingers are immobilized in extension in the splint, but the thumb is free to move. After reconstruction of a ruptured EPL tendon or transfer of the EIP tendon to restore thumb extension, the wrist is immobilized in extension and the thumb in adduction, but the fingers are free to move.

Continuous immobilization of the wrist and digits is maintained for approximately 3 to 4 weeks to protect the healing tendons.^73,140 Daytime splinting is discontinued at about 12 weeks, but night splinting typically continues for 6 months or longer.

During each phase of postoperative rehabilitation after extensor tendon transfer or reconstruction, exercises are progressed very gradually. Precautions during exercise and functional use of the hand are summarized in Box 19.9.

During the first 6 weeks after surgery, the priorities of rehabilitation are edema control and protection of the transferred or reconstructed tendon(s), followed by carefully controlled mobility of the operated areas to prevent adherence of healing tissues. It is usually permissible to remove the protective splint for exercise at around 3 to 4 weeks. If tendon quality is poor and the security of the sutured tissues is in question, exercise may be delayed until about 6 weeks postoperatively.

Goals and interventions. The goals and intervention during the first phase of rehabilitation include the following.^54,73,140

• Maintain mobility of the elbow and forearm, unsplinted digits, and other involved joints.

  • While the operated hand is immobilized, perform active ROM of all necessary joints.

• Re-establish mobility and control of the repaired or transferred extensor muscle-tendon units.

  • When the splint may be removed for exercise, initiate active wrist motions with the fingers relaxed.

  • Begin assisted MCP extension of each of the fingers or thumb with the wrist and IP joints of each digit stabilized in neutral.

  • Perform place and hold exercises by passively positioning the operated MCP joint first in a neutral and later in a slightly extended position. Have the patient briefly hold the position. This emphasizes end-range extension to prevent an extensor lag.

  • Progress to dynamic MCP extension with the wrist in neutral, initially from slight MCP flexion with the palm of the hand on a table and the fingers relaxed over the edge.

• Regain active flexion of the digits.

  • Initiate MCP flexion of the fingers by having the patient relax the EDC after active extension rather than actively flexing the fingers.

  • Progress to active MCP flexion within a protected range with the wrist and PIP joints stabilized in neutral. With the wrist and MCP joints stabilized in extension, actively flex (hook fist/intrinsic minus position) and extend (straight hand position) the PIP joints. PIP flexion while in wrist and MCP extension prevents stiffness of the IP joints without placing a stretch on the repaired EDC tendon(s).⁴⁸

By 6 to 8 weeks postoperatively, the transferred or reconstructed tendon can withstand greater imposed stresses. Use of the hand for light functional activities usually begins at this time. At about 8 weeks, daytime splinting is gradually decreased and typically discontinued by 12 weeks postoperatively. If there is an extensor lag, splint use during the day continues over a longer period of time.

Goals and interventions. Consider the following goals and interventions to progress the rehabilitation program.

• Continue to increase active mobility of the operated digits.

  • Add gentle passive stretching to increase MCP extension or flexion if one or both motions are restricted.

  • Continue active MCP extension exercises to prevent an extensor lag, or consider dynamic extension splinting if an extensor lag has developed and persists. If MCP extension to neutral is possible (no extensor lag), perform active MCP extension with the palm of the hand on a flat surface, and extend each finger beyond neutral.

  • With the wrist in neutral or slight extension, gradually increase MCP flexion by touching each fingertip to the palm of the hand (first straight and then full-fist positions) or the thumb to each fingertip and gradually to the base of the fifth finger. At 8 to 12 weeks, institute dynamic flexion splinting intermittently during the day if grasp is significantly limited.

• Regain strength, control, and functional use of the hand.

  • Incorporate active movements of the digits into manual dexterity and coordination activities that simulate functional activities. Remove the splint for functional activities that involve light grasp, such as picking up or holding light objects or folding clothing.

  • Around 8 to 12 weeks add isometric and dynamic, submaximal resistance exercises to improve functional strength and endurance of the hand.

  • Through ongoing patient education, reinforce principles of joint protection during functional use of the hand.

Repetitive Trauma Syndromes/Overuse Syndromes

Disorders from cumulative or repetitive trauma in the wrist and hand lead to significant loss of hand function and lost work time.⁹ The causes are related to repeated movements over an extended period of time. The resulting inflammation can affect muscles, tendons, synovial sheaths, and nerves. Diagnoses include carpal tunnel syndrome, trigger finger, de Quervain's disease, and tendinopathy (tendonitis/tenosynovitis). Management of impairments related to carpal tunnel syndrome and nerve compression in the tunnel of Guyon is described in Chapter 13.

Tendinopathy

Etiology of Symptoms

Pathological breakdown of the tendon structure results from continued or repetitive use of the involved muscle beyond its ability to adapt, the effects of RA, a stress overload to the contracting muscle (such as strongly gripping the steering wheel during a motor vehicle accident), or roughening of the surface of the tendon or its sheath.^38,99

Common Structural and Functional Impairments

• Pain whenever the related muscle contracts or whenever there is movement that causes gliding of the tendon through the sheath.

• Warmth and tenderness with palpation in the region of inflammation.

• In RA, synovial proliferation and swelling in affected tendon sheaths, such as over the dorsum of the wrist or in the flexor tendons in the carpal tunnel.

• Frequently, an imbalance in muscle length and strength or poor endurance in the stabilizing muscles. The fault may be more proximal in the elbow or shoulder girdle, causing excessive load and substitute motions at the distal end of the chain.

Common Activity Limitations and Participation Restrictions (Functional Limitations/Disabilities)

A common limitation of tendinopathy is the inability to perform repetitive or sustained work, recreational, or leisure gripping activities or hand motions that require contraction of the involved musculotendinous unit due to pain that worsens with the provoking activity.

Management: Protection Phase

Follow the guidelines for acute lesions described in Chapter 10, with special emphasis on education, relieving the stress in the involved musculotendinous unit, and maintaining a healthy environment for healing with nondestructive forces.

• Patient education. Inform the patient how the mechanism of injury and repetitive activity is provoking the symptoms and explain the necessity to modify the activity to allow healing. Engage the patient in the rehabilitation program.

• Rest the part. Splint the related joints to rest the involved tendon.

• Tendon mobility. If the tendon is in a sheath, apply cross-fiber massage while the tendon is in an elongated position, so mobility develops between the tendon and sheath.

  • Teach the patient tendon-gliding exercises to prevent adhesions. (These are described in the exercise section of this chapter.)

• Muscle integrity. Teach the patient how to perform multi-angle muscle setting in pain-free positions followed by pain-free ROM.

Management: Controlled Motion and Return to Function Phases

• Exercise progression. Progress to dynamic exercises, adding resistance within the tolerance of the healing musculotendinous structure. Eccentric exercises that load the tissue should be carefully monitored in order not to provoke recurrence of the symptoms.

• Biomechanical assessment. Assess the biomechanics of the functional activity provoking the symptoms and design a program to regain a balance in the length, strength, and endurance of the muscles. Frequently, problems arise in the wrist and hand because of poor stabilization or endurance in the shoulder or elbow.

• Prevention. Continue to emphasize the importance of self-monitoring the symptoms, maintaining a safe exercise program, and unloading the wrist/hand when symptoms occur.³⁸

Traumatic Lesions of the Wrist and Hand

Simple Sprain: Nonoperative Management

After trauma from a blow or a fall, an excessive stretch force may strain the supporting ligamentous tissue. There may be a related fracture, subluxation, or dislocation.

Common Structural and Functional Impairments

• Pain at the involved site whenever a stretch force is placed on the ligament

• Possible hypermobility or instability in the related joint if supporting ligaments are torn

Common Activity Limitations and Participation Restrictions (Functional Limitations/Disabilities)

• With a simple sprain, pain may interfere with functional use of the hand for a couple of weeks whenever the joint is stressed. There is no limitation of function if a splint or tape can be worn to protect the ligament, and the splint does not interfere with the task.

• With significant tears, there is instability, and the joint may subluxate or dislocate with provoking activities, requiring surgical intervention.

Management

Follow the guidelines in Chapter 10 for treating acute lesions with emphasis on maintaining mobility while minimizing stress to the healing tissue. If immobilization is necessary to protect the part, only the involved joint should be immobilized. Joints above and below should be free to move. This maintains mobility of the long tendons in their sheaths that cross the involved joint. Avoid positions of stress and activities that provoke the symptoms while healing. Cross-fiber massage to the site of the lesion may help prevent the developing scar from adhering and restricting motion.

Lacerated Flexor Tendons of the Hand: Surgical and Postoperative Management

Background and Indications for Surgery

Lacerations of the flexor tendons of the hand, which can occur in various areas (zones) along the volar surface of the fingers, palm, wrist, and distal forearm, are common and cause an immediate loss of hand function, consistent with the tendons severed. The musculotendinous structures damaged depend on the location and depth of the wound. Damage to one or more tendons may be accompanied by vascular, nerve, and skeletal injuries, which can cause additional loss of function and complicate management. An acute rupture of a flexor tendon may also occur as the result of a closed traumatic injury to the hand.^36,119

The volar surfaces of the forearm, wrist, palm, and fingers are divided into five zones; the thumb is divided into three zones. These zones are illustrated in Figure 19.12. The anatomical landmarks for each of the zones are described in Box 19.10.^{36,56,76,109,119,120} Use of this system of classifying lacerations improves consistency of communication and can provide a basis for predicting outcomes.⁸²

Knowledge of the complex anatomy and kinesiology of the hand is essential to understand the impairments and functional implications caused by damage to the flexor tendons in each of these zones. Box 19.11 identifies common impairments associated with damage in each of the zones.^36,76

When severed or ruptured, flexor tendons readily retract, thus requiring surgical intervention in most instances to restore function to the hand and prevent deformity. Repair and rehabilitation of lacerations in zone II, traditionally referred to as "no-man's land," pose a particular challenge to hand surgeons and therapists.⁷⁸ Because of the confined space in which the extrinsic flexors of the fingers lie and the limited vascular supply to the tendons in zone II, healing tissues in this area are prone to excursion-restricting adhesions. Scar tissue formation during the healing process can interrupt tendon-gliding in the synovial sheath and subsequently restrict ROM of the involved fingers.

In zone IV (the carpal tunnel), the extrinsic flexor tendons of the digits (FDS, FDP, FPL) lie in close proximity to each other. An injury in this zone may lead to adherence of adjacent tendons to each other in the carpal tunnel and impairment of differential gliding between the tendons.

Procedures

Many factors influence the type of surgical repair selected to manage a flexor tendon injury.^{36,56,76,109,118,119,120} Injury-related factors include the mechanism of injury; the type and location (zone) of the laceration; the extent of associated skin, vascular, nerve, and skeletal damage; the degree of wound contamination; and the time elapsed since the injury. Surgery-related factors include timing of the repair, the need for staging surgeries, and the hand surgeon's background and experience. Patient-related influences are the patient's age, health, and lifestyle (especially nutrition and smoking). These factors also have a significant impact on postoperative rehabilitation and outcomes of a tendon repair.⁷⁸

Types of repair or reconstruction. Surgical options for repair of lacerations or a closed rupture of flexor tendons can be classified by the type of procedure.^{36,76,79,109,119}

• Direct repair. An end-to-end repair in which the tendon ends are re-opposed and sutured together.

• Tendon graft. An autogenous donor tendon (autograft), such as the palmaris longus, is sutured in place to replace the damaged tendon. This is necessary when the ends of the severed tendon(s) cannot be brought together without undue tension. Tendon grafts are performed in one or more stages depending on the severity, type, and location of injury.

A straight laceration usually lends itself well to a direct (end-to-end) repair, whereas a jagged laceration that frays the tendon may require a tendon graft.

Timing of a repair. Another method of classifying and describing tendon repairs is the timing of the repair, as related to the elapsed time since the injury. The timing of a repair after an acute tendon injury is critical, because the severed ends of the tendon begin to soften and deteriorate quickly, and the proximal portion of the tendon retracts. These factors make it difficult to reattach the tendon with a strong repair at its normal length. However, only a tendon laceration associated with major damage to the vascular system is considered an emergency situation.^36,76,119 Although better outcomes are thought to occur if the repair is done within the first few days, a delay of up to 10 days yields results equal to those of an immediate repair. Delays beyond 2 weeks are associated with poorer outcomes.^36,119 If a repair must be delayed for more than 3 to 4 weeks, a direct repair is no longer possible, which necessitates a tendon graft.³⁶

Categories of surgeries based on elapsed time include:36,58,76,109,119,120

• Immediate primary repair: A repair done within the first 24 hours after injury.

• Delayed primary repair: A repair performed up to 10 days after injury.

• Secondary repair: A repair done 10 days to 3 weeks after injury.

• Late reconstruction: Surgery performed well beyond 3 to 4 weeks, sometimes months after the injury.

• Staged reconstruction: Multiple separate surgeries performed over a period of weeks or months.^58,79 A staged reconstruction enables a surgeon to prepare an extensively damaged or scarred tendon bed months prior to a tendon graft, so adhesions are less likely to develop.

A simple, clean, acute laceration of a tendon without associated injuries of the hand is most often managed with a direct primary repair, either immediate or delayed a few days.^36,119,120 However, if the wound is not clean, a delayed primary repair allows time for medical intervention to reduce the risk of infection. Lengthy delays that necessitate a secondary repair or late reconstruction are often associated with multiple injuries, such as extensive skin loss, fractures that cannot be stabilized immediately, or long-standing scarring and contractures. If there is damage to one or more of the tendon pulleys, these must be repaired before the lacerated tendon can be repaired effectively.

Of the multiple-stage reconstructions for extensive and complex flexor tendon injuries of the hand, the Hunter two-stage reconstruction passive or active implant is most widely known. During the first stage of this procedure, the scarred and adherent portions of the damaged flexor tendon are resected. An implant (rod) made of silicone is then secured in place to act as a tendon spacer around which a new sheath develops over a period of 3 months. In addition, a damaged retinacular pulley system is reconstructed, and any contractures are released during the first surgery. During the second phase, the implant is removed, and a donor tendon (graft) is drawn through the new sheath and sutured in place.^58,79

Some general aspects of the many variations of operative procedures for primary flexor tendon injuries are described in this section.^{36,76,79,82,118,119,120} However, careful review of a patient's operative report and close communication with the hand surgeon are necessary sources of specific details of each patient's surgery.

Surgical approach. For example, for repair of lacerated finger tendons in zone II, a volar, zigzag approach, designed to avoid the lines of stress or a lateral incision, may be elected by the surgeon, the volar zigzag approach is the more common. When approaching the lacerated tendon, the incision is made between the annular pulleys to ensure optimal excursion. This approach preserves the function of these fibrous sheaths, which encircle the finger flexors and keep the tendons close to the joints, preventing bowstringing of the tendon.

Suturing technique. For a direct repair after the tendon ends are located, prepared, and re-opposed, there are a number of delicate techniques for suturing the tendons.^{36,76,107,111,118,119,120} Core sutures and epitendinous sutures are used to hold the tendon ends together. A larger number of suture strands across the repair site (e.g., four or six strands instead of two) produces a proportionally stronger repair. Running, locked epitendinous sutures used in addition to core sutures appear to further increase the initial strength of the repair.^107,111

Suturing technique must also address the vascular supply to the repaired tendon. Nonreactive sutures are placed in the nonvascular volar aspect of the tendon so as not to disturb the vincula, which lies in the dorsal aspect of the tendon and provides a blood supply to the tendon.^{36,77,109,118,119,120} When present, as in zones II and IV, the synovial sheath is also repaired to re-establish circulation of synovial fluid, an important source of nutrition to the healing tendons.¹¹⁸

Closure. After all repairs have been completed, the incision(s) is closed, and the hand and wrist are immobilized in a bulky compression dressing and elevated to control edema. The compression dressing remains in place for 1 to 3 days. When the bulky surgical dressing is removed, it is replaced with a light compressive dressing and splint.

General considerations. After surgical intervention for a flexor tendon injury, a strong, well-healed tendon that glides freely is the cornerstone for restoring functional mobility and strength in the hand.^{50,93,118,119,120} Every effort is made to prevent excursion-restricting adhesions from forming while simultaneously protecting the repaired tendon as it heals. Box 19.12 summarizes the factors that contribute to adhesion formation after tendon repair.^{36,50,57,82,93,119}

Many of the same patient and injury-related factors—already noted—that a surgeon weighs when determining the most appropriate approach to surgical management for a patient's hand injury also influence the complex components and progression of postoperative rehabilitation. In addition, surgery-related factors, including the type and timing of the repair, suturing technique, strength of the tendon repair, and the need for concomitant operative procedures affect rehabilitation and eventual outcomes. Furthermore, therapy-related factors—in particular the time at which therapy is initiated, the use of early or delayed mobilization procedures, the quality of splinting, the expertise of the therapist, and ultimately the quality and consistency of the patient's involvement in the rehabilitation process—influence outcomes.

Extensive research has been done on the process of tendon healing, the tensile strength of tendon repairs, adhesion formation, and tendon excursion and imposed stresses (loading) on a repaired tendon during digital motion. A number of sources provide an in-depth analysis and summary of basic and clinical studies, typically animal and cadaveric but some in vivo human studies, as they apply to rehabilitation.^{25,36,50,57,58,93,118,119,120}

The purpose of this section is to examine and summarize current concepts and approaches to immobilization and exercise used in rehabilitation after flexor tendon injury and repair, rather than to put forth or ascribe to any one particular approach or protocol. Therapists treating patients after tendon repair must be familiar with the various postoperative protocols or guidelines used by referring hand surgeons and those described in the literature.

A therapist's knowledge of the underlying concepts in any protocol is essential for effective communication with the surgeon. A therapist's skill in applying and teaching exercise procedures is equally necessary for effective patient education and helping a patient achieve optimal functional outcomes. This knowledge enables a therapist to make sound clinical judgments to determine when the progression of activities in a protocol preferred by a referring surgeon is safe or when activities must be adjusted based on each patient's responses. Remember, a regimented protocol is only safe and effective when there are no postoperative variables, a situation that certainly does not occur in the clinical setting.

Approaches to postoperative management. There are two basic approaches to management after flexor tendon repair characterized by the timing and type of exercises in the program. They are categorized as early controlled motion, either passive or active, and delayed motion.

Numerous published protocols with considerable variability fall within these categories. Most current-day programs emphasize early controlled (protected) motion after surgery and include both passive and active exercises of the operated digit(s). Advances in surgical management (in particular, improved suturing techniques) that establish a relatively strong initial tendon repair allow the use of early motion.

Box 19.13 summarizes the rationale for early, but carefully graded, motion as soon as a day or two after tendon repair based on four decades of evidence derived from scientific studies.^* However, there are instances when a traditional, delayed motion approach must be used. Indications for prolonged (3 to 4 weeks) immobilization after tendon repair (and therefore delayed motion) are noted in Box 19.14.^{17,90,93,109,118,119}

Key elements of early passive and active motion approaches and the delayed motion approach with regard to immobilization and selection and progression of exercises are presented in the following sections. More detailed descriptions of these approaches, as well as specific protocols advocated by various practitioners and researchers, are available in many sources.^*

With all approaches, the postoperative goals and interventions for pain reduction, edema control, and maintenance of function in uninvolved regions (e.g., the elbow and shoulder) are consistent with management following other operative procedures previously discussed in this chapter. Patient education is of the utmost importance for effective outcomes after hand surgery.

NOTE: Unless otherwise noted, the guidelines described in this section for immobilization and exercise are for injury and primary repair or one-stage tendon grafts of the FDS and/or FDP muscle-tendon units in zones I, II, and III. The guidelines are similar but not addressed for zones T-I and T-II of the thumb. Postoperative guidelines for multistage or late reconstructions are progressed in a similar but more cautious manner. Refer to other resources for this information.^58,93,109

The duration, type, and position of immobilization must be considered.

Duration of immobilization. With some exceptions previously noted (see Box 19.14), when prolonged immobilization (3 to 4 weeks) is necessary, the repaired tendon is continuously immobilized after surgery for up to 5 days while the bulky compression dressing is kept in place. This allows some time for postoperative edema to decrease.

Type or method of immobilization. This usually depends on the preference of the hand surgeon and therapist, the approach to postoperative exercise, and the stage of tissue healing. If motion of the operated digit is to be delayed for 3 to 4 weeks, a cast or static splint provides the immobilization. Early controlled motion approaches require the fabrication of different types of customized splints.

There are three general types of splint used after flexor tendon repair: a static dorsal blocking splint;^{27,45,50,93,115,119} a dorsal blocking splint with dynamic traction, originally proposed by Kleinert and colleagues^66,70 and subsequently modified and improved by clinicians and researchers;^{50,93,111,115} and a dorsal tenodesis splint with a wrist hinge.^{24,25,118,119,120} Descriptions of these static and dynamic splinting techniques for immobilization and/or exercise are noted in Box 19.15. Figure 19.13 shows an example of a dorsal blocking splint with dynamic traction. The splint allows active extension of the involved finger, and the elastic band passively returns the finger to a flexed position. (See Figure 19.14 A for a depiction of a dorsal tenodesis splint.)

Position of immobilization. The typical position of immobilization for repairs of flexor tendons in zones I, II, and III is wrist and MCP flexion coupled with PIP and DIP extension. This position prevents full lengthening and undue stress on the repaired FDS and/or FDP tendons while minimizing the risk of IP flexion contractures. The recommended degrees of wrist and MCP flexion differ somewhat from one source to another. Recommended positions range from 10° to 45° of wrist flexion and from 40° to 70° of MCP flexion with the IP joints in full but comfortable extension.^{24,25,27,36,45,50,93,115, 118,119,120} The wrist typically is positioned in less flexion than the MCP joints. The trend over the years has been to fabricate splints that allow less wrist and MCP flexion than early protocols recommended to increase patient comfort and reduce the risk of carpal tunnel syndrome.^50,93

The wrist is typically positioned at neutral with 70° MCP flexion following a zone IV repair.⁹³

There are two basic approaches to the application of early, controlled motion to maintain tendon-gliding and prevent tendon adhesions after flexor tendon repair: early passive motion and early active motion. The way in which passive or active motion of the repaired tendon is achieved, however, varies among protocols.

Early controlled passive motion. Historically, the use of early passive motion is based on the work of Duran and Houser⁴⁵ and of Kleinert and associates.^66,70 Both proposed early passive flexion of the IP joints within a protected range postoperatively, but used different approaches to splinting and exercise. Duran advocated use of a static dorsal blocking splint and early removal of the splint or loosening of the stabilization straps for passive ROM exercise of the IP joints of the operated finger(s). Kleinert and colleagues advanced use of a dorsal splint with dynamic traction for early exercise (see Fig. 19.13). Within the confines of the splint, the patient performs active extension of the operated finger. The elastic band returns the finger to a flexed position with each repetition after the finger extensors relax, causing excursion of the repaired tendon without active tension in the finger flexors. A manual push into maximum DIP flexion may be added to increase passive flexion.

NOTE: When a dynamic traction splint is used during the day, a static splint is worn at night. The splint holds the IP joints in neutral and the wrist and MCP joints in flexion to prevent IP flexion contractures.

These original passive motion protocols have been modified over the past three decades. Today, some surgeons and therapists use selected elements (splinting and/or exercise) of these passive motion approaches.^{25,27,50,93,133,135} However, use of early active motion that imposes controlled stresses on the repaired tendon is gradually replacing passive motion approaches.¹¹⁸

Early controlled active motion. The primary feature that distinguishes an early active motion from an early passive motion approach is the use of minimum-tension, active contractions of the repaired muscle-tendon units initiated during the acute stage of tissue healing, often by the first 24 to 72 hours but no later than 5 days postoperatively.^{25,49,50,107,110,111, 118,119,120,133} Some passive exercises also are incorporated into active regimens.

Based primarily on experimental studies using animal models, it is hypothesized that gentle stresses placed on a repaired tendon by means of a very low-intensity static or dynamic muscle contraction, which "pulls" the repaired tendon through its sheath, is a more effective method of creating tendon excursion (gliding) than "pushing" the tendon with passive motion.^{49,50,57,109,111,118,119} Early active motion has become more widely accepted, because stronger suturing techniques produce a repair that can withstand early, controlled stresses.

PRECAUTION: Proponents of early, active tendon mobilization caution that this approach is recommended only for primary tendon repairs, using the stronger four- and six-strand core and epitendinous suture techniques (in contrast to two-strand suturing) in carefully selected patients who have access to rehabilitation with an experienced hand therapist and are most likely to adhere to the prescribed exercise and splinting regimen.^{24,25,49,50,57,93,119,120}

There are two ways in which early active motion can be implemented. Both methods are founded on an analysis and application of evidence in the scientific literature on tendon repair and healing, tendon excursion, and imposed loading on repaired tendons.^{107,110,111,118,119,120}

• Place-and-hold approach. One approach uses "place-and-hold" exercises by means of static muscle contractions to generate active tension of the finger flexors and impose controlled stress on the repaired tendon. (Place-and-hold exercises are described in the phase-specific exercises that follow.) This approach to early active motion is used in the Indiana protocol.^{24,25,82,118,119,120}

• Dynamic approach. The other approach to early active motion, developed by Evans^49,50 and others,^107,110,111 uses dynamic, short-arc, minimum muscle tension exercises to impose initially low-intensity stresses on the healing tendon.

• Combined approach. Proposed by Groth,⁵⁷ a recently developed conceptual model for the use of early active motion and application of progressive forces to the healing tendon after flexor tendon repair combines elements of both the place-and-hold and dynamic approaches. In addition, in the rationale for this model, Groth discusses the effects of each level of exercise on internal tendon loads and tendon excursion supported by key evidence from the literature when available.

  • A unique feature of Groth's model is that it is criterion-based rather than time-based. By providing criteria for progressing exercises based on optimal tendon loading, this program provides a mechanism for an individualized sequence of exercises adjusted for each patient rather than using predetermined timelines for progression.

  • The model contains eight progressive levels of active exercises, from the least to the greatest levels of loading on the tendon. The sequence is preceded by warm-up exercises (slow, repetitive passive finger motions in protected ranges). As with other early active motion approaches, exercises are begun during the first few days after surgery and are progressed until conclusion of postoperative rehabilitation. Box 19.16 describes the eight-level sequence of exercises in Groth's conceptual model.⁵⁷

A number of retrospective studies and prospective, nonrandomized case series have been published describing the effectiveness of early active motion or early passive motion approaches to postoperative rehabilitation following flexor tendon repair. The following prospective, randomized study,¹³³ which was recently published, directly compared these two approaches to therapy and therefore is an important addition to the body of evidence.

Results of the study demonstrated that total active IP ROM of the repaired digits was significantly greater and flexion contractures significantly smaller in the active motion group than the passive motion group at each of the four postoperative assessment points. In the group treated with active motion, 94% (51 of 54 digits), compared with 62% (32 of 52 digits) of the passive motion group, had "good" or "excellent" results (> 125° of combined active PIP and DIP motion) at one year. Patient satisfaction at one year also was greater in the active motion group. However, there were no significant differences in dexterity and functional outcomes between groups at one year. Tendon ruptures occurred in two digits (4%) in both groups with 3 of the 4 ruptures occurring in the little finger. Of interest is that smokers, regardless of group assignment, had poorer outcomes than nonsmokers.

NOTE: The guidelines for exercises described in this section focus on the application of early active motion after zone I, II, or III primary flexor tendon repairs and are drawn from several resources.

The maximum protection phase of rehabilitation begins within the first few days after surgery and continues for 3 to 5 weeks. This is the period of time when the tendon repair is weakest. The goals of this phase of rehabilitation are pain and edema control and protection of the newly repaired tendon while imposing very low-level, controlled stresses on the tendon to maintain adequate tendon gliding and prevent adhesions that can restrict tendon excursion. Interventions in this phase include elevating the hand, splint use and care, wound management and skin care, and passive and active exercises.

During the first phase of rehabilitation, most exercises are performed in a static dorsal blocking splint or in a wrist tenodesis splint (Fig. 19.14 A) specifically designed for exercise. With both methods of splinting, the stabilization straps are loosened to allow finger flexion. The following exercises are performed frequently during the day and continue for about the first 4 weeks.

• Passive ROM exercises. On an hourly basis perform passive MCP, PIP, and DIP flexion and extension of each individual joint to the extent the dorsal splint allows, followed by composite passive flexion in the confines of the splint. Composite flexion can include passive movements into full fist and straight fist positions.

• Independent motions of the PIP and DIP joints for differential gliding of the FDP and FDS tendons. For example, the DIP joint must be flexed and extended separately while each PIP joint is stabilized in flexion. In this way, as the DIP joint is passively extended, the FDP repair site glides distally, away from the FDS repair.^93,117

PRECAUTION: It is essential to maintain the MCP joints in flexion during passive ROM of the IP joints to avoid excessive stretch of the repair site, which could cause gapping of the re-opposed tendon ends during IP extension.

• Place-and-hold exercises. Many programs initiate place-and-hold exercises of the repaired digit with the patient wearing either a dorsal blocking splint^49,50,111 or a tenodesis splint.^{24,25,57,118,119,120} With the MCP joints in flexion, passively place the IP joints in a partially flexed position and have the patient hold the position independently for 5 seconds with a minimum static contraction of the finger flexors. If the patient is wearing a tenodesis splint, combine place-and-hold finger flexion with active wrist extension (Fig. 19.14 B and C). Have the patient relax and allow the wrist to passively flex and the digits to passively extend. Initially, have the patient practice this with the uninjured hand or use biofeedback to learn how to hold the position with a minimum of force production in the FDP and FDS.

• Minimum-tension, short-arc motion. Some programs begin active, dynamic finger flexion during the first few days after surgery if the suturing technique and strength of the repair allow.^49,50 Active contractions that generate minimum tension—just enough tension to overcome the resistance of the extensors and cause flexor tendon excursion—are performed with the wrist in slight extension and the MCP joints flexed.

The moderate protection phase begins at about 4 weeks and continues until 8 weeks postoperatively. The focus during this phase is on safely increasing stresses on the repaired tendon and achieving full active flexion and extension of the wrist and digits and differential gliding of the tendons. If a tenodesis splint was worn for early active exercises, it is discontinued at the beginning of this phase. However, use of the static dorsal blocking splint continues during the day except for exercise until at least 6 to 8 weeks. Use of a night splint continues for protection or to decrease or prevent a flexion contracture. Exercises include:

• Place-and-hold exercises. Continuation of place-and-hold exercises but with gradually increasing tension.

• Active ROM. Continuation or initiation of active composite flexion and extension of the IP joints with the MCP joints flexed, MCP flexion/extension with the IP joints relaxed, and active wrist flexion and extension with the fingers relaxed.

• Tendon-gliding and blocking exercises. These exercises are initiated at about 5 to 6 weeks (see Fig. 19.17 A through E, Fig. 19.18 A through C, and descriptions in the final section of this chapter).

PRECAUTION: Avoid finger extension combined with wrist extension for about 6 to 8 weeks, as this position places extreme tension on the repaired flexor tendon.

The minimum protection/return to function phase begins at approximately 8 weeks postoperatively and is characterized by gradually progressed use resistance exercises to improve strength and endurance, dexterity exercises, and use of the hand for light (1 to 2 lb) functional activities. (Refer to the final section of this chapter for suggested exercises and activities.)

Protective splinting is discontinued, but intermittent splinting may be necessary if the patient has a persistent extensor lag or flexion contracture. After primary flexor tendon repairs, most patients return to full activity by 12 weeks after surgery.

In instances where continuous immobilization of a repaired flexor tendon extends for 3 to 4 weeks (see Box 19.14 for indications), some degree of tendon healing and adhesion formation already has occurred by the time exercises can be initiated.

PRECAUTION: Despite the extended period of immobilization, at 3 to 4 weeks, the tendon repair must still be protected in a dorsal blocking splint, and exercises must be performed in protected positions and progressed gradually.

Exercises such as passive ROM, tendon-blocking and tendon-gliding, and active ROM can be initiated when the cast is removed. Exercises used in early motion approaches are appropriate. The reader also is referred to additional resources that provide detailed exercise programs when delayed mobilization is necessary.^17,93,115

Lacerated Extensor Tendons of the Hand: Surgical and Postoperative Management

Background and Indications for Surgery

Laceration and traumatic rupture of the extensor tendons of the fingers, thumb, or wrist are more common than in the flexor tendons.⁴³ Their superficial location makes the extensor tendons vulnerable to damage when trauma occurs to the dorsum of the hand. Furthermore, extensor tendons in the digits are substantially thinner than flexor tendons, making them more prone to traumatic rupture.^43,88,101

As with the flexor surface, the extensor surface of the hand, wrist, and forearm is divided into zones (Fig. 19.15). The dorsal surface of the fingers and wrist are divided into seven zones, and the thumb into four zones. Each of these zones is identified by specific anatomical landmarks, as noted in Box 19.17.^{43,46,56,88,101} The odd-number zones correspond to the location of the DIP, PIP, MCP, and wrist joint regions. Although not depicted in Figure 19.15, the dorsal surface of the distal and middle forearm is often identified as zones VIII and IX, respectively. The area at the CMC joint of the thumb is often identified as zone T-V.⁸⁸

The extensor mechanism of the hand and wrist is complex. The structural characteristics of these mechanisms vary in each zone. Damage in one zone produces compensatory imbalances in adjacent zones. Knowledge of the anatomy and kinesiology of the extensor mechanism is basic to an understanding of how a patient's physical impairments and functional limitations occur according to the structures damaged in each zone. Box 19.18 identifies key structures and characteristic impairments associated with tendon rupture or laceration by zone.^43,46,88,101 Of all the extensor zones, injuries in zones III and VII pose the greatest surgical and rehabilitative challenges.

Depending on the type and location of injury to the extensor mechanism and the extent of associated skeletal, joint, vascular, or nerve damage, surgery may or may not be indicated. The tendons of the extensor system distal to the dorsum of the hand have many soft tissue attachments along various structures, making extensor tendons far less likely to retract when lacerated or ruptured than flexor tendons.^44,88,101 Consequently, with a rupture (closed injury) or a simple laceration in a peripheral zone, the tendon is re-opposed and managed by uninterrupted immobilization in a splint or cast for 6 weeks as it heals.^44,101 For example, this is a common course of treatment for a mallet finger (or thumb) deformity, which is a closed rupture of the terminal extensor tendon in zone I, usually from forceful hyperflexion.⁸⁸

Nevertheless, surgical intervention, even for a simple distal tendon injury, usually is necessary to restore active ROM, muscular balance, strength, and function to the hand and prevent contractures and deformity. Although the extensor muscles of the digits are substantially weaker than the flexors, an intact extensor mechanism is essential for functional grasp and release.

Procedures

Surgical options for extensor tendon repair include a direct (end-to-end) repair or a reconstruction. As with flexor tendon repair or reconstruction, surgeries are classified as primary (immediate repair or delayed up to 10 days), secondary repair, and late or staged reconstruction.^22,43,88,101 Reconstruction usually involves use of a graft. These terms already have been defined in the previous section of this chapter on flexor tendon repair and rehabilitation. Operative procedures, such as tendon transfers, for ruptured, diseased extensor tendons associated with RA also were described earlier in the chapter.

Although similar definitions exist for extensor and flexor tendon procedures, there are substantial differences in operative techniques used to repair extensor versus flexor tendons. These differences are based largely on the fact that extensor tendons are morphologically thinner than flexor tendons. This fact led to the belief that extensor tendon repairs are more prone to gapping, have less tensile strength, and are more likely to rupture than flexor tendons after repair. However, stronger suturing techniques, specifically designed for extensor tendon repair and reconstruction, are used more frequently today, allowing early postoperative mobilization of the repaired tendon while lessening concerns of gapping and rupture.^43,46,114

Zone III/IV primary repair. Operative procedures for repair of lacerated or ruptured extensor tendons vary significantly in the distal versus the proximal zones. In this overview only repair of a zone III/IV laceration (the most common cause of injury in these zones) is described, simply as an example. Detailed descriptions of operative techniques for primary repair and late reconstruction of extensor tendons in all zones of the hand, wrist, and forearm can be found in several sources.^{10,22,43,56,88,101}

With an acute laceration of the PIP joint and middle phalanx, the wound often enters the joint space. Therefore, the area must be débrided, cleansed, and treated with antibiotics. The central slip, which refers to the extensor mechanism in zones III and IV, then can be managed with a direct repair.^43,56,88 The severed tendon is repaired and then sutured into the fibrocartilaginous dorsal plate of the middle phalanx, which is thicker and holds sutures better than the central slip, thereby producing a stronger repair.⁴³

NOTE: The suturing and repair technique in zones III and IV may decrease the overall length of the tendon by 2 to 3 mm, causing a loss of 2° to 5° of PIP flexion.⁸⁸

If damaged, the lateral bands are repaired. If a boutonnière deformity is evident or likely to develop, a K-wire may be inserted to immobilize the PIP joint in extension for about 3 weeks and then removed. After closure of the area, a bulky compression dressing immobilizes the repaired tissues and controls edema.

Postoperative Management

General considerations. The overall goal of postoperative rehabilitation after extensor tendon injury and repair is the same as after flexor tendon repair—that is, to restore mobility and strength to the hand and wrist for functional activities. Adhesion formation is a concern in the extensor tendons after repair, just as it is after repair of the flexor tendons. As noted previously, extensor tendons of the fingers are less likely to retract after laceration or rupture because of the extensor mechanism's multiple soft tissue linkages to surrounding structures. However, these attachments make extensor tendons prone to adhesion formation and loss of excursion during the healing process. At the dorsum of the hand, the extensor tendons are relatively mobile, but also are surrounded by synovial sheaths to which they may adhere if immobilized over a period of time.^43,88,101 As with management after flexor tendon repair, emphasis after extensor tendon repair is placed on preventing adhesions that restrict tendon gliding and limit joint ROM and functional use of the hand. (Refer to Box 19.12 to review factors that contribute to adhesion formation.)

The components and progression of postoperative rehabilitation and eventual outcomes after extensor tendon repair are influenced by many of the same factors that influence rehabilitation and outcomes of flexor tendon repair, including the location (level) and severity of the injury; the specifics of the surgical procedure(s), particularly the type of suturing technique and strength of the repair; and the timing of and the patient's access and commitment to a supervised rehabilitation program with an experienced hand therapist.^{26,46,114,117,135}

Approaches to postoperative management. Two general approaches to rehabilitation after surgical repair of extensor tendon injuries are described in the literature: prolonged, uninterrupted immobilization with motion of the injured region(s) delayed for 3 to 6 weeks or, in carefully selected patients, early controlled passive or active motion initiated during the first few postoperative days. The latter is based on the same rationale as for early mobilization of flexor tendon repairs (see Box 19.13).

Historically, prolonged immobilization has been used more widely than early motion after extensor tendon repair, perhaps because of concerns that inadvertent but forceful or rapid movements could cause gapping or rupture of the repair if the splint or cast is removed early in the healing process¹⁰ or simply that alternative forms of immobilization, such as dynamic splinting, are cumbersome and more costly for the patient.⁹⁶ Given these issues, the use of early motion after extensor tendon repair has evolved more slowly than it has for use after flexor tendon repair.

There are situations when an extended immobilization/delayed motion approach is the only appropriate method of management (see Box 19.14). Some studies continue to show that in many instances this traditional approach yields acceptable reults.⁹⁶ However, during the past two to three decades, some studies have shown that extensor tendon repairs, managed with prolonged immobilization, are more likely to develop adhesions, resulting in only marginal outcomes (increased incidence of extensor lag, joint contracture, boutonnière deformity).^28,89 In addition, these and other studies have demonstrated that early motion programs after primary repair of acute extensor tendon injuries in zones III and VII are effective and safe^{18,19,35,47,48,59,63,103,128} and produce superior outcomes compared with prolonged immobilization/delayed motion programs.^{28,35,47,89,103} Consequently, early motion approaches have become more widely used in recent years.

It should be noted, however, that prolonged immobilization continues to be the most frequently selected method of treating zone I and II extensor tendon injuries.^44,88,101 Late reconstruction, which is more complex and usually involves tendon grafts, also is managed in most cases with continuous, extended immobilization and delayed motion.²²

The first early motion programs for extensor tendons involved passive mobilization, with dynamic extension splinting, which allows active flexion followed by passive extension (see Fig. 19.11).^28,48,89,103 In these programs, although active flexion is initiated just a few days after surgery, active digital extension—at least at the level of the repair—typically is delayed for 4 to 5 weeks.^{18,19,28,35,59,103} For an explanation of dynamic extension splinting after extensor tendon repair, refer to the earlier section of this chapter on repair of tendon ruptures associated with RA.

Although dynamic extension splinting for early mobility of the extensor tendons continues to be used, there is a growing trend to incorporate controlled active extension into early mobilization programs.^{26,46,47,63,128} Following a brief overview of immobilization procedures, key elements of early active motion and delayed motion approaches to rehabilitation after extensor tendon repair are presented.

Immobilization

Immobilization typically is maintained with a volar (palmar) splint after the bulky surgical dressing is removed a few days postoperatively. The duration of immobilization, the type(s) of immobilization selected, the joints immobilized, and the position of immobilization are based on the location (zone) of the injury and repair and the structures involved.

Duration of immobilization. If a patient is a good candidate for an early motion program, the duration of uninterrupted immobilization often is just a few days. If delayed motion is a more appropriate course of action, uninterrupted immobilization ranges from 3 to 6 weeks. In early motion programs, some type of protective splinting is used during exercise for about 6 weeks after surgery.

Types of immobilization. Either static or dynamic splinting or a combination of both is used. Depending on the joints immobilized, a forearm and wrist-based or a hand-based splint is indicated to block excessive flexion at the region of the repair and prevent stretching of the repaired tendon(s). A static splint is considered a low-profile splint, whereas a dynamic splint (see Fig. 19.11) with its outrigger secured to the dorsal surface of the splint for the elastic band and sling attachments is a high-profile splint. The slings and elastic band attachments hold the digits in extension at rest but allow active flexion.

For a delayed motion program, a static volar or bivalved circumferential splint is fabricated and worn on a continuous basis (other than daily skin care). A dynamic splint, worn during the day for frequent exercise sessions, is an integral component of many early motion programs, but a static splint must be worn at night to protect the repair. Some early active motion programs use only static splints that allow active motion when the straps are loosened but otherwise prevent excessive motion of joints. Special static template splints for the repaired digits also are fabricated and used only during short-arc exercises to limit the range of allowable motion (see Fig. 19.16).

The joints are immobilized in an extended position or a position that places only minimal tension on the tendon to protect the repair from excessive stretch and potential gapping. As examples, for a zone III/IV repair, the PIP and sometimes the DIP joints are placed in extension, but for a zone V/VI repair, the wrist is held in 30° of extension and the MCP joints in 30° to 45° of flexion. Recommended positions of the joints proximal or distal to the injured zone vary considerably. Several resources provide detailed information on immobilization and splinting procedures after extensor tendon repairs.^26,46,114

Exercise: Early Controlled Active Motion Approach

As interest in the application of early active motion after tendon repair has grown, so have the number of studies describing details of exercise programs and outcomes. In addition to one example of an early active motion program for zone III/IV repairs presented in this section, guidelines for early mobilization of zones V, VI, and VII also have been proposed and detailed in the literature.^{26,46,63,114,128}

As noted previously, extensor tendon repairs in zones III and IV are especially prone to adhesion formation because of multiple soft tissue attachments of the extensor mechanism to surrounding structures and the broad bone-tendon interface of the proximal phalanx along which the extensor mechanism must glide.^{43,46,56,88,101} Evans^46,47 proposed an early motion program of splinting and exercise for repairs of the central slip that involves minimal active tension of the repaired extensors for controlled, short-arc motion of the PIP and DIP joints.

Key elements of the early, short-arc, active motion program for central slip repairs include the following splinting and exercise procedures.^26,46,47

Use of customized static volar splints. Several types of customized splints are used with this approach. A static, hand-based volar splint is fabricated and applied as soon as the surgical dressing is removed. It holds only the PIP and DIP joints in 0° extension; the wrist and MCP joints are free. This splint is removed for exercise on an hourly basis during the day but replaced between exercise sessions.

• A forearm-based resting splint is worn at night for protection for at least 6 weeks postoperatively.

• Two static, volar, finger-based, template splints are fabricated and worn only during exercise to limit joint motion, extensor tendon excursion, and the level of stress on the repaired central slip. One splint (Fig. 19.16) is molded to limit PIP flexion to 30° and DIP flexion to 20° or 25° during exercise. A second template splint is fabricated to hold the PIP joint in full extension during isolated DIP flexion limited to 30° to 35°.

• The PIP exercise splint is revised during the second week of exercise to allow 40° of flexion if no extensor lag is present. The PIP flexion allowed by the splint is increased incrementally by 10° each week thereafter.

Exercise progression. The patient is taught the concept of minimum active tension (MAT) to protect healing tissues during tendon excursion. MAT is just enough tension generated during an active muscle contraction to overcome the elastic resistance of an antagonist.⁴⁷

• Exercises are initiated within the first few postoperative days and performed hourly during the day. While actively holding the wrist in 30° of flexion and manually stabilizing the MCP joint in neutral to slight flexion, the patient performs active PIP and DIP flexion within the limits allowed by the PIP exercise splint (see Fig. 19.16 A), followed by full active extension held for several seconds (see Fig. 19.16 B).

• The patient also performs active, isolated DIP flexion/extension in the second volar template splint that stabilizes the PIP joint in full extension.

• Exercises continue regularly during the day for several weeks using revised exercise splints. Ideally, by the end of 4 weeks, the patient achieves 70° to 80° of active flexion and full extension of the PIP joint.

• Composite MCP, PIP, and DIP flexion (full fist) is postponed for at least 4 weeks or when the exercise splints have been discontinued.

• By 6 to 8 weeks, low-intensity resisted exercises are initiated along with gradual use of the hand for functional activities.

Exercise: Delayed Mobilization Approach

If a traditional approach to postoperative management of extensor tendon repairs is used, exercises are delayed for at least several weeks after surgery. Special considerations and precautions for exercise using a delayed motion approach are summarized by zones in Box 19.19.^{17,26,46,96,114,135}

Guidelines for resistance exercises to strengthen the hand and continuation or modification of splinting for protection are not addressed in this summary. In general, splinting is continued during the day if an extensor lag persists and at night for protection for about 12 weeks. If grasp is limited because of insufficient finger flexion, passive stretching is initiated, or dynamic flexor splinting may be incorporated into the program by alternating flexion and extension splints.

Resistance to the repaired muscle-tendon unit is not initiated until 8 to 12 weeks postoperatively regardless of the site of the repair. First, emphasis is placed on gradually strengthening the extensors to prevent or minimize an extensor lag. After 10 to 12 weeks, low-intensity resisted grasp and pinch activities are initiated to gradually strengthen the flexors if no extensor lag is present.

Techniques for Musculotendinous Mobility

Active muscle contraction and specific motions of the digits and wrist are used to maintain or develop mobility between the multijoint musculotendinous units and other connective tissue structures in the wrist and hand. Because adhesions between the various structures can become restrictive or incapacitating, tendon-gliding exercises and tendon-blocking exercises are used whenever possible to develop or maintain mobility. This is particularly important when there has been immobilization after trauma; surgery; or fracture, and scar tissue adhesions have developed. If restrictions occur as a result of scar tissue adherence between tendons or between tendons and surrounding tissues, mobilization techniques described in this section may be necessary. General stretching techniques also may be necessary; they are described in the next section. The tendon-gliding and tendon-blocking exercises described here also may be used to develop neuromuscular control and coordinated movement.

Tendon-Gliding and Tendon-Blocking Exercises

Place-and-Hold Exercises

Place-and-hold exercises are a form of gentle muscle setting (static/isometric) exercises that are used during the early postoperative period following tendon repair before active ROM is initiated but when a minimal level of stress on the repaired tendon and passive joint movement are beneficial for maintaining joint mobility and tendon excursion.

• Following flexor tendon repair, the patient usually wears a dorsal blocking splint^49,50,111 or a tenodesis splint.^{24,25,118,119,120} With the MCP joints in flexion, passively place the IP joints in a partially flexed position and have the patient hold the position independently for 5 seconds with a minimum static contraction of the finger flexors.

• If the patient is wearing a tenodesis splint, combine place-and-hold finger flexion with active wrist extension (see Fig. 19.14 B and C). Have the patient relax and allow the wrist to passively flex and the digits to passively extend.

• Following extensor tendon repair, when the volar blocking splint may be removed for exercise, passively position the joint in the zone of the repair first in a neutral and later in a slightly extended position. Then, have the patient hold the position. This emphasizes end-range extension to prevent an extensor lag.

• Have the patient practice the exercise with the uninjured hand or use biofeedback to learn how to hold the position with a minimum of force production.

Flexor Tendon-Gliding Exercises

Flexor tendon-gliding exercises are designed to maintain or develop free gliding between the FDP and FDS tendons and between the tendons and bones in the wrist, hand, and fingers.^105,112,136 There are five positions in which the fingers move during tendon-gliding exercises: straight hand (all the joints are extended); hook (claw) fist (MCP joints are extended, IP joints are flexed); full fist (all the joints are flexed); table-top position, also known as the intrinsic plus hand (MCP joints are flexed, IP joints are extended); and straight fist (MCP and PIP joints are flexed, IP joints are extended) (Fig. 19.17). The following progression is suggested.

• Initiate the exercises with the wrist in neutral position.

• Once full range of the finger motions is achieved, progress to doing the gliding\exercises with the wrist in flexion and in extension to establish combined finger and wrist mobility.

• Full excursion and tendon-gliding of all the extrinsic muscles are accomplished by starting with the wrist and fingers in full extension, then moving to full wrist and finger flexion, and then reversing the motion.

Hook (Claw) Fist Position

Have the patient move from the straight hand to the hook fist position by flexing the DIP and PIP joints while maintaining MCP extension (Fig. 19.17 A and B). Maximum gliding occurs between the profundus and superficialis tendons and between the profundus tendon and the bone. (There is also gliding of the extensor digitorum communis tendons; this motion is used with the extensor gliding exercises.)

Full Fist

Have the patient move to the full fist position by flexing all the MCP and IP joints simultaneously (Fig. 19.17 C). Maximum gliding of the profundus tendon with respect to the sheath and bone as well as over the superficialis tendon occurs.

Straight Fist (Sublimis Fist)

Have the patient move from the table-top position (Fig. 19.17 D) to the straight fist position by flexing the PIP joints while maintaining the DIP joints in extension (Fig. 19.17 E). Maximum gliding of the superficialis tendon occurs with respect to the flexor sheath and bone.

Thumb Flexion

Have the patient flex the MCP and IP joints of the thumb full range. This promotes maximum gliding of the flexor pollicis longus.

Flexor Tendon-Blocking Exercises

Blocking exercises for the flexor tendons (Fig. 19.18) not only develop gliding of the tendons with respect to the sheaths and related bones, they also require neuromuscular control of individual joint motions. Therefore, they use the mobility gained by the flexor tendon-gliding exercises and are a progression of the flexor tendon-gliding exercises. Progress to manual resistance as the tissues heal and can tolerate resistance.

PRECAUTION: These exercises should not be used in the early stages of flexor tendon healing after repair because of the stress placed on the tendons.

Patient position and stabilization: Sitting with the forearm supinated and the back of the hand resting on a table. The opposite hand provides stabilization and "blocking" against unwanted movement. Each finger performs the exercise separately.

Isolated MCP Flexion (Lumbricals and Palmar Interossei)

• Have the patient flex only the MCP joint of one digit (Fig. 19.18 A).

• If necessary, stabilize the rest of the fingers in extension against the table with the other hand.

• With improved control, the hand does not have to be stabilized against the table.

PIP Flexion (Flexor Digitorum Superficialis)

• Have the patient stabilize the proximal phalanx of one digit with the opposite hand, and if possible, flex just the PIP joint of the one digit while keeping the DIP joint extended and the rest of fingers on the table (Fig. 19.18 B).

• If the patient has difficulty doing this, stabilize the other digits in extension with the opposite hand.

DIP Flexion (Flexor Digitorum Profundus)

• Have the patient attempt to flex just the distal phalanx (Fig. 19.18 C).

• Stabilize the middle phalanx of one digit with the other hand.

• Vary this exercise by increasing the range of MCP and PIP flexion to the point at which the patient just begins to lose DIP motion; stabilize in this position and have the patient attempt DIP flexion.

Full Fist

When full independent tendon-gliding is available, the patient should be able to make a full fist. Progress the exercises described by adding resistance.

Exercises to Reduce an Extensor Lag

The extrinsic finger extensors (extensor digitorum communis, extensor digitorum indicis, and extensor digiti minimi) are more superficial than the flexor tendons and therefore more easily damaged. Their prime function is to extend the MCP joints. Extension of the IP joints requires active interaction with the intrinsic muscles of the hand via the extensor mechanism. Adhesions within their sheaths at the wrist or between tendon and bone restrict tendon-gliding both proximally (restricting active finger extension) and distally (restricting active and passive finger flexion).

When full passive range of extension is available, but the person cannot actively move the joint through the full range of extension, it is called an extensor lag. An extensor lag can occur as the result of weakness, but is frequently caused by adhesions that prevent gliding of the tendons when the muscles contract.

One purpose of the following exercises is to maintain mobility and thus prevent adhesions. The exercises also are used to regain control of finger extension. Mobilization of adhesions is described immediately following the differential gliding of extensor tendon exercises. Stretching techniques are described in the next section.

Isolated MCP Extension

• Have the patient move from the full fist position (see Fig. 19.17 C) to the hook fist position (see Fig. 19.17 B).

• If the patient has difficulty maintaining the IP joints in flexion, have him or her hook the fingers around a pencil while extending the MCP joints.

• Begin with the wrist in neutral and progress to positioning the wrist in flexion and extension while performing MCP extension.

Isolated PIP and DIP Extension

Extension of the interphalangeal joints requires intrinsic and extrinsic muscle (extensor digitorum communis) control.

• For strongest participation of the lumbricals, stabilize the MCP joint in flexion while the patient attempts IP extension, moving from the full fist position (see Fig. 19.17 C) to the table-top position (see Fig. 19.17 D).

• Progress to stabilizing the palm of the hand on the edge of a table (or block) with the PIP or DIP joint partially flexed over the edge.

• Have the patient extend the involved phalanx through the ROM.

Terminal-Range Extension of IP Joints

• Progress to the terminal range by stabilizing the entire hand, palm side down on a flat surface, and have the patient extend the involved phalanx into hyperextension.

• If there is not enough range available, place a pencil or block under the proximal phalanx or middle phalanx, so the PIP or DIP joint can go through a greater range (Fig. 19.19).

Extensor Tendon-Gliding Exercises

Differential gliding of the extensor digitorum communis tendons to each of the fingers can be achieved by the following progression.

• Teach the patient to passively flex the MCP and IP joints of one finger with the opposite hand while actively maintaining the other fingers in extension.

• If the patient has difficulty doing this, begin with the involved hand resting on a table with the palm up. Stabilize three of the four fingers against the table while passively flexing one of the digits (Fig. 19.20). Then instruct the patient to attempt to actively keep the fingers against the table while one of the digits is passively flexed.

• Progress by having the patient actively maintain the fingers in extension with the fingers spread out and then actively flex each finger in turn while the other fingers remain extended.

• Have the patient flex the middle and ring fingers while maintaining extension of the index and little fingers (long horn sign). This promotes isolated control of the extensor indicis and extensor digiti minimi tendons and promotes their gliding on the extensor digitorum communis tendons.

Scar Tissue Mobilization for Tendon Adhesions

Ideally, the tendon-gliding exercises described previously in this section maintain or develop mobility between the long tendons and surrounding connective tissues or within their sheaths. However, when there has been inflammation and immobilization during the healing process following trauma or surgery, scar tissue adhesions may form and prevent gliding of the tendons. Contraction of the muscle does not result in movement of the joint or joints distal to the site of the immobile scar.

Techniques to mobilize the adhesive scar tissue include the application of friction massage directly to the adhesion. This is superimposed on active and passive stretching techniques (described in the next section), and the tendon-gliding techniques already described. To apply friction massage, hold the tendon in its lengthened position; apply pressure with your thumb, index, or middle finger and massage perpendicular to the tendon and longitudinally in proximal and distal directions. A sustained force against the adhesion allows for creep and eventual movement of the scar. Techniques to mobilize the flexor and extensor tendons follow.

To Mobilize the Long Finger Flexor Tendons

Adhesions between the flexor tendons and their sheaths or between tendons and underlying bones restrict tendon-gliding in both a proximal and distal direction, so the joints distal to the scar do not flex when the muscle contracts. Passive movement into flexion of the joints distal to the adherent scar is possible if there are no capsular restrictions. Full range of extension of the joints distal to the scar is not possible actively or passively owing to the inability of the tendon to glide distally.

The following is a suggested progression in intensity of scar tissue mobilization.

• Begin the stretching routine by passively moving the tendon in a distal direction by extending the finger joints as far as possible and applying a sustained hold to allow for creep. Follow this with active contraction of the flexor muscle to create a stretch force against the adhesion in a proximal direction¹¹² using the patterns of movement described for tendon-gliding exercises (see Fig. 19.17).

• If active and passive stretching, described in the above technique, does not release the adhesion, extend the MCP and IP joints as far as allowed, stabilize them, and apply friction massage with your thumb or finger at the site of the adhesion while the tendon is held in its stretched position.³⁷ Apply the massaging stretch force across the tendon and in a longitudinal direction, both proximally and distally. When applying friction massage in a proximal direction, ask the patient to simultaneously contract the flexor muscle in order to superimpose an active stretch force.

• After friction massage, have the patient repeat the flexor tendon-gliding exercises to utilize any gained mobility.

To Mobilize the Extensor Tendons and the Extensor Mechanism

If the extensor tendons or extensor mechanism has restricted mobility because of adhesions, muscle action is not transmitted through the mechanism to extend the joint or joints distal to the restriction. Without free gliding, an extensor lag may result. As defined earlier, an extensor lag is the loss of active extension when there is full passive extension. The following is a progression in intensity of scar tissue mobilization.

• Stretch the adhesion in a distal direction by passively flexing the joint distal to the site. Follow this by having the patient attempt to actively extend the joint and put tension on the scar in a proximal direction.

PRECAUTION: If the extensor lag increases (i.e., flexion increases, but there is no active extension through the increased range), the tendon distal to the adhesion, rather than the adhesion, may be stretching. Do not continue with passive stretching into flexion, but rather, emphasize friction massage applied to the scar tissue.

• Apply friction massage at the site of the adhesion with the tendon kept taut by holding the joint at the end of its range of flexion. Apply friction massage across the fibers and in a distal and proximal direction. When applying friction massage in a proximal direction, have the patient actively contract the extensors to assist with the mobilization effort.

• Follow these mobilization techniques with extensor tendon-gliding exercises, as described in the previous section.

Exercise Techniques to Increase Flexibility and Range of Motion

Stretching the muscles and connective tissue structures of the wrist and hand requires knowledge of the unique anatomical relationships of the multijoint musculotendinous units and the extensor mechanism of the digits. These are described in the first section of this chapter. The principles and techniques of stretching are presented in Chapter 4, and special note is made of the importance of stabilization when stretching the multijoint muscles of the hand and fingers. This is reemphasized here. In addition, because scarring and adhesions can restrict tendon-gliding and therefore motion of the digits, it is important to recognize these restrictions and utilize specific techniques that address the adhesions as presented in the previous section (see 'Scar Tissue Mobilization for Tendon Adhesions'). Before stretching muscle or connective tissue, there also should be normal gliding of the joint surfaces to avoid joint damage. Use joint mobilization techniques to stretch the joint capsule and restore gliding (see Chapter 5).

NOTE: Patient position for most wrist and hand exercises is sitting with the forearm supported on a treatment table unless otherwise noted.

General Stretching Techniques

When stretching to increase wrist flexion or extension, it is important that the fingers are free to move, so the extrinsic finger flexor and extensor musculotendinous units do not restrict motion at the wrist. Similarly, when stretching ligaments and other periarticular connective tissues across individual finger joints, it is important that there is no tension on the multijoint tendons. The following techniques are initially applied by the therapist and then are taught to the patient as self-stretching techniques for a home exercise program when he or she understands how to safely apply the stretch force and stabilization.

To Increase Wrist Extension

• Have the patient place the palm of the hand on a table with the fingers flexed over the edge. Use the other hand to stabilize the dorsal surface of the hand to maintain the palm against the table. Then have the patient move the forearm up over the stabilized hand (similar to Fig. 19.22 except the fingers are over the edge of the table, so they are free to flex, and the stretch occurs only at the wrist).

• Have the patient place the palms of the hands together at right angles to each other and allow the fingers to intertwine and flex. Instruct the patient to press the restricted hand in a dorsal direction with the palm of the other hand and sustain the stretch.

To Increase Wrist Flexion

• Have the patient place the dorsal surface of the hand on a table. Use the other hand to provide stabilization against the palm of the hand. Have the patient move the forearm up over the stabilized hand.

• Have the patient sit with the forearm pronated and resting on a table and the wrist at the edge of the table. Press against the dorsal surface of the hand with the opposite hand to flex the wrist.

• Have the patient place the dorsum of both hands together. Then, with the fingers relaxed, move the forearms so the wrists flex toward 90°.

To Increase Flexion or Extension of Individual Joints of the Fingers or Thumb

To increase extension at any one joint, begin by positioning the patient's forearm on a table in supination; to increase flexion, position the forearm in pronation. Place the phalanx to be stretched at the edge of the table. Show the patient how to apply the stretch force against the distal bone while stabilizing the proximal bone against the table.

Stretching Techniques for the Intrinsic and Multijoint Muscles

Self-Stretching the Lumbricals and Interossei Muscles

Have the patient actively extend the MCP joints, flex the IP joints, and apply a passive stretch force at the end of the range with the opposite hand (Fig. 19.21 A).

Self-Stretching the Interossei Muscles

Have the patient place the hand flat on a table with the palm down and the MCP joints extended. Instruct the patient to abduct or adduct the appropriate digit and apply the stretch force to the distal end of the proximal phalanx. Holding the adjacent digit provides stabilization.

Self-Stretching the Adductor Pollicis

Have the patient rest the ulnar border of the hand on the table and abduct the thumb perpendicular to the palm of the hand. Instruct the patient to apply the stretch force with the crossed thumb and index or long finger of the other hand against the metacarpal head of the thumb and index finger and attempt to increase the web space (Fig. 19.21 B).

PRECAUTION: It is critical that the patient does not apply the stretch force against the proximal or distal phalanx. This places stress on the ulnar collateral ligament of the MCP joint of the thumb and can lead to instability at that joint and poor functional use of the thumb. Abduction occurs at the CMC joint at the articulation between the metacarpal and the trapezium.

Manual Stretching of the Extrinsic Muscles

Because they are multijoint muscles, the final step in a stretching progression is to elongate each tendon of the extrinsic muscles over all the joints simultaneously. However, do not initiate stretching procedures in this manner, because joint compression and damage can occur to the smaller or less stable joints. Begin by allowing the wrist and more proximal finger joints to relax; stretch the tendon unit over the most distal joint first. Stabilize the distal joint at the end of the range and then stretch the tendon unit over the next joint. Next, stabilize the two joints, and stretch the tendon over the next joint. Progress in this manner until the desired length is reached.

PRECAUTION: Do not let the PIP and MCP joints hyperextend as the tendons are stretched over the wrist.

Self-Stretching the Flexor Digitorum Profundus and Superficialis

Have the patient begin by resting the palm of the involved hand on a table; then extend the DIP joint, using the other hand to straighten the joint. While keeping it extended, have the patient straighten the PIP and MCP joints in succession. If the patient can actively extend the finger joints to this point, the motion should be performed unassisted. With the hand stabilized on the table, have the patient then begin to extend the wrist by bringing the arm up over the hand. The patient moves just to the point of feeling discomfort, holds the position, then progresses as the length increases (Fig. 19.22).

Self-Stretching the Extensor Digitorum Communis

The fingers are flexed to the maximum range, beginning with the most distal joint first and progressing until the wrist is simultaneously flexed. The opposite hand applies the stretch force.

Exercises to Develop and Improve Muscle Performance, Neuromuscular Control, and Coordinated Movement

Exercises described in this section are for use during the controlled motion and return to function phases of rehabilitation when the tissues are in the subacute and chronic stages of healing and require only moderate or minimum protection. In addition to the conditions already described in this chapter, imbalances in the length and strength of the wrist and hand muscles may be caused by nerve injury, trauma, disuse, or immobilization.

Appropriate exercises to develop fine finger dexterity or strength and muscular endurance for strong or repetitive gripping can be selected from the following exercises or their adaptations. The flexor tendon blocking exercises and extensor tendon-gliding exercises described previously in this section also may be used to strengthen the musculature by adding resistance manually or mechanically. Exercises for shoulder, elbow, and forearm strength and muscular endurance also should be included to restore proper function in the upper extremity.

Techniques to Strengthen Muscles of the Wrist and Hand

If the musculature is weak, use progressive strengthening exercises, beginning at the level of the patient's ability. Use active-assistive, active, or manual resistance exercises as described in Chapters 3 and 6 of this text. Use mechanical resistance to progress strengthening exercises.

To Strengthen Wrist Musculature

Allow the fingers to relax. Exercise the wrist muscles in groups if their strength is similar. If one muscle is weaker, the wrist should be guided through the range desired to minimize the action of the stronger muscles. For example, with wrist flexion, if the flexor carpi radialis is stronger than the flexor carpi ulnaris, have the patient attempt to flex the wrist toward the ulnar side as you guide the wrist into flexion and ulnar deviation. If the muscle is strong enough to tolerate resistance, apply manual resistance over the fourth and fifth metacarpals.

Wrist Flexion (Flexor Carpi Ulnaris and Radialis) and Extension (Extensor Carpi Radialis Longus and Brevis and Extensor Carpi Ulnaris)

Have the patient sit with the forearm supported on a table, grasping a weight or elastic resistance that is secured on the floor. The forearm is supinated to resist flexion or pronated to resist extension (Fig. 19.23).

Wrist Radial Deviation (Flexor and Extensor Carpi Radialis Muscles and Abductor Pollicis Longus) and Ulnar Deviation (Flexor and Extensor Carpi Ulnaris Muscles)

While standing, have the patient hold a bar with a weight on one end. To resist radial deviation, the weight is on the radial side of the wrist (Fig. 19.24 A); to resist ulnar deviation, the weight is on the ulnar side of the wrist (Fig. 19.24 B).

Functional Progression for the Wrist

Progress to controlled patterns of motion requiring stabilization of the wrist for functional hand activities such as repetitive gripping, picking up and releasing objects of various sizes and weights, and opening and closing the screw lid on a jar. Develop endurance and progress to the desired functional pattern by loading the upper extremity to the tolerance of the wrist stabilizers. When the stabilizers begin to fatigue, stop the activity.