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Computer design synthesis of a below knee-Syme prosthesisA detailed design synthesis analysis of the BK Syme prosthesis is provided, to determine the socket's cutout orientation size and shape, cutout fillet shape, socket wall thickness distribution and the reinforced fiber distribution in the socket wall, for a minimally stressed structurally safe lightweight prosthesis. For analysis purposes, the most adverse socket loading is obtained at the push-off stage of gait; this loading is idealized as an axial in-plane loading on the bottom edge of the circular cylindrical socket shell whose top edge is considered fixed. Finite element stress analysis of the socket shell (with uniform and graded wall thickness) are performed for various orientations of the cutout and for various types of corner fillets. A lateral cutout with a streamline fillet is recommended. The wall material (i.e., thickness) distribution is determined so as to minimize the stresses, while ensuring that the wall material's stress limits are not exceeded. For such a maximally stressed lightweight socket shell, the panels in the neighborhood of the cutout are checked to ensure that they do not buckle under their acquired stresses. A fiber-reinforced laminated composite socket shell is also analyzed in order to recommend optimum variables in orientations and densities of reinforcing fibers.
Document ID
Document Type
Reprint (Version printed in journal)
Elangovan, P. T. (Eindhoven Technische Hogeschool, Eindhoven, Netherlands)
Ghista, D. N. (NASA Ames Research Center Biomedical Research Div., Moffett Field, Calif., United States)
Alwar, R. S. (Indian Institute of Technology Madras, India)
Date Acquired
August 9, 2013
Publication Date
March 1, 1979
Publication Information
Publication: Computer Programs in Biomedicine
Volume: 9
Subject Category
Distribution Limits