The term goniometry is derived from two Greek words: gonia, meaning "angle," and metron, meaning "measure." Therefore, goniometry refers to the measurement of angles, in particular the measurement of angles created at human joints by the bones of the body. The examiner obtains these measurements by placing the parts of the measuring instrument, called a goniometer, along the bones immediately proximal and distal to the joint being evaluated. Goniometry may be used to determine both a particular joint position and the total amount of motion available at a joint.
The elbow joint is evaluated by placing the parts of the measuring instrument on the humerus (proximal segment) and the forearm (distal segment) and measuring either a specific joint position or the total arc of motion (Fig. 1.1).
The left upper extremity of an individual in the supine position is shown. The parts of the measuring instrument have been placed along the proximal (humerus) and distal (radius) body segments and centered over the axis of the elbow joint. When the distal segment has been moved toward the proximal segment (elbow flexion), a measurement of the arc of motion can be obtained.
Goniometry is an important part of a comprehensive examination of joints and surrounding soft tissue. A comprehensive examination typically begins by interviewing the individual and reviewing records to obtain an accurate description of current symptoms; functional abilities and activities of daily living; occupational, social, and recreational activities; and medical history. Observation of the individual's body to assess bone and soft tissue contour, as well as skin and nail condition, usually follows the interview. Gentle palpation is used to determine skin temperature and the quality of soft tissue deformities and to locate pain symptoms in relation to anatomical structures. Anthropometric measurements such as leg length, leg circumference, and body volume may be indicated.
The performance of active joint motions by the individual during the examination allows the examiner to screen for abnormal movements and gain information about the individual's willingness to move. If abnormal active motions are found, the examiner performs passive joint motions in an attempt to determine reasons for joint limitation. Performing passive joint motions enables the examiner to assess the tissue that is limiting the motion, detect pain, and make an estimate of the amount of motion. Goniometry is used to measure and document the amount of active and passive joint motion as well as abnormal fixed joint positions.
Following the examination of active and passive range of motion, resisted isometric muscle contractions, joint integrity and mobility tests, and special tests for specific body regions are used in conjunction with goniometry to help identify the injured anatomical structures. Tests to assess muscle performance and neurological function are often included. Diagnostic imaging procedures and laboratory tests may ...