Volume 41 Number
4, July/August 2004
Pages 535 — 546
Heel-region properties of prosthetic feet and shoes
Glenn K. Klute, PhD; Jocelyn S. Berge, MSE; Ava D. Segal, BAS
Department of Veterans Affairs, Puget Sound Health Care System, Seattle, WA; Department of Mechanical Engineering, University of Washington, Seattle, WAAbstract — The properties of the prosthetic components prescribed to amputees have the potential to ameliorate or exacerbate their comfort, mobility, and health. To measure the difference in heel-region structural properties of currently available prosthetic feet and shoes, we simulated the period of initial heel-ground contact with a pendulum apparatus. The energy dissipation capacity of the various prosthetic feet ranged from 33.6% to 52.6% of the input energy. Donning a shoe had a large effect. Energy dissipation of a Seattle Lightfoot 2 prosthetic foot was 45.3%, while addition of a walking, running, and orthopedic shoe increased energy dissipation to 63.0%, 73.0%, and 82.4%, respectively. The force versus deformation response to impact was modeled as a hardening spring in parallel with a position-dependent damping element. A nonlinear least-squares curve fit produced model coefficients useful for predicting the heel-region impact response of both prosthetic feet and shoes.Key words: amputation, artificial limbs, biomechanics, prosthetics, rehabilitation.
