Orthotic compensation for non-functioning hip extensors

Abstract

Three point fixation to stabilise joints using a rigid orthosis is relatively simple. When movement is required in a single plane, a hinge can be incorporated preventing superfluous movement and consequent loss of stability and function. Alternatively the Reciprocating Gait Orthosis (RGO) which utilises a system of Bowden cables with a HKAFO to provide reciprocal flexion and extension forces at the hip joint may be used. Free standing is achieved in the RGO by trunk and arm movements, the cable tension effectively "locking" the hips in neutral. Force transfer through the cables also produces reciprocal gait. The upper limbs acting through external supports provide the initiating force, producing truncal extension and subsequent hip extension of the stance leg. The resulting flexion of the swing leg produces a forward step. Currently 40 patients have been fitted with the orthosis in Salford, of whom 22 are Spina Bifida patients (aged 3-34 years). Most have Thoraco-lumbar or upper Lumbar lesions. The device has performed well with 1 episode of "knee clash" and 3 patients have had structural failures. Functional walking has been achieved with the orthosis.