A modified shank for below knee prosthesis

Abstract

A below knee (BK) prosthesis is a device used to compensate for missing limb segments in patients with BK amputations as an aid for locomotive and other daily activities It consists of three main parts: socket, shank, and artificial foot. The shank is merely a shaft of a suitable length to serve as a frame structure to transfer biomechanical forces between the socket and foot. In traditional BK prostheses, the shank is made from rigid metallic or composite material tube (Teflon), while in the current work, a modified version is suggested with internal stiffness and damping characteristics to act as energy storage and shock absorber. A mathematical model was thus employed to analyse the impact behaviour from walking gait, and the main parameters studied were the effective mass of impact, loading rate, and knee pre-swing angular velocity. The modified prosthesis was tested with a BK amputation patient and compared with a traditional prosthesis in force platform and treadmill tests. The results showed some improvement in patient gait parameters; at stance phase, it smoothed the GRF curve; at heel strike, both the effective mass of impact and loading rate increased by 16% and 22%, indicating good impact reduction, and at pre swing, it increased the initial flexion angle and angular velocity by 13% and 15%, respectively, enhancing the swing phase.

Synthesis of crystalline nanocellulose and its effect on the mechanical properties of E-glass fiber/epoxy composite for prosthetic shank applications

“…Thus, for those stated reasons lower amputation can occur at the knee, ankle, hip or at the extension parts in between the joints. 3 Prosthesis which is a customized artificial limb that can be employed to enhance residual limbs with amputation which can ease daily activities of the amputees should be used. 4 A prosthetic limb is composed of three primary parts; the socket, the extension, and the foot or hand.…”

Fatigue and Tensile Characteristics for Composite Materials Used in Prosthetic Socket

“…Yassr Y. Kahtan worked on the modal analysis of below knee sockets using finite element software (ANSYS Workbench 15) [31]. Saif M. Abbas studied the fatigue characteristics with analysis modeling for a new resin with carbon fiber and nile glass of the above knee prosthetic socket [32,33].The research aims to study the properties of materials used to reinforce prosthetic limbs by replacing artificial fibers with natural fibers.…”

Buckling analysis of prosthetic pylon tubes using finite element method

“…The three main components of the transtibial prosthesis are the socket, the pylon and the artificial foot. The pylon or the shank is a shaft with appropriate length that serves as a frame structure to transfer biomechanical forces between the socket and the foot [1,2]. In traditional below knee prosthesis, the pylon can be made from rigid metallic, polymeric or composite materials.…”

“…A modified version of metallic pylon with the incorporation of a rubber pad showed an internal stiffness and damping characteristics, that acted as shock and energy absorber. The modified pylon was tested in a below-knee amputated patient and results showed improvements in patient gait performance, notably better impact reduction and more effective loading rate [1]. A composite pylon using perlon fibers showed that the new prosthetic pylon has good mechanical properties, lighter than standard metal pylons, and more economically viable with respect to the standard metal pylon [5].…”