This chapter focuses on interventions to improve intermediate trunk and hip control using kneeling postures. Kneeling offers the benefit of achieving improved trunk and hip control without the demands required to control the knee and ankle. Inherent to these upright, antigravity postures are important prerequisite requirements for standing. For example, kneeling postures are particularly useful for developing initial upright postural control and for promoting hip extension and abduction stabilization control required for standing. By eliminating the demands of upright standing, patient anxiety and fear of falling are typically diminished. Kneeling activities also provide important lead-up skills for independent floor-to-standing transfers.
The postures addressed in this chapter are kneeling (Fig. 6.1A) and half-kneeling (Fig. 6.1B). In kneeling, both hips are extended, with bilateral weightbearing occurring primarily at the knees and upper tibia, with the legs and feet resting on the support surface. This creates a wider base of support (BOS) than that seen in standing but not as wide as seen in half-kneeling. In half-kneeling, one hip remains extended, with weightbearing at the knee and upper leg; the opposite hip and knee are flexed to approximately 90 degrees, with weightbearing occurring at the foot placed forward on the supporting surface. In kneeling postures, height of the center of mass (COM) is intermediate.
(A) Kneeling posture. Both hips are extended, with bilateral weightbearing on the knees and legs; the BOS is narrow. (B) Half-kneeling posture. One hip is extended, with weightbearing on the knee and leg. The opposite hip and knee are flexed to approximately 90 degrees with slight abduction; the foot is forward and placed flat on the support surface. The BOS is wide and angled on a diagonal between the posterior and anterior limbs.
Clinical Note: Patients with significant cerebellar dysfunction and ataxia (e.g., the patient with traumatic brain injury [TBI] or cerebellar degeneration) benefit from practice in these more stable postures. For these patients, kneeling and half-kneeling are functionally important as transitional activities in preparation for upright standing.
In kneeling, the COM is intermediate; it is higher than in supine or prone positions and lower than in standing. The BOS is influenced by the relative length of the leg and foot and is positioned largely posterior to the COM. Thus, this posture is more stable posteriorly than anteriorly. Owing to this relative anterior instability, trunk and hip extensors must compensate for any forward shift in the COM. This is an important safety issue: If the patient does not have the ability to compensate (e.g., has trunk and hip extensor weakness), anterior displacement may cause the patient to fall forward.
Kneeling involves head, trunk, and hip muscles for upright postural control. The head and trunk are maintained vertically in midline orientation with normal ...