The effects of prosthetic foot type and visual alteration on postural steadiness in below-knee amputees
Lateral stability is controlled by alternate hip adductor and abductor activation. However, the lower limb amputee has insufficient control of Centre of Mass and prosthetic foot type may influence ability to balance.
Patients classified as engaging in K2-K3 activities were each tested with three different types of prosthetic foot:
- Solid ankle cushion heel (SACH), non-articulating foot
- Single-axis foot (SA), one hinge
- Energy saving & return foot (ESAR) flex-foot with multi-axial ankle.
A balance device was used to take 6 measures of stability: overall, anterior-posterior and medial-lateral stability: both with eyes-open and eyes-closed. The SACH and ESAR foot showed significant differences in stability when visual cues were removed. The results showed that the type of foot had no significant influence on standing postural stability although, it was proposed that the stiffness of the ankle constrained excursion of the Centre of Mass, explaining the trend of improved stability in the SACH foot. >From: Arifin et al., Biomed Eng Online 13 (2014) 23. All rights reserved to The Authors.
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