Design and analysis of a novel prosthetic limb for lower knee amputee

The optimal performance of a prosthetic limb depends on its biomechanical characteristics along with its mechanical aspects. Biomechanical analysis of an economical, customized and reliable prosthetic limb for amputees in accordance with their body type by observing the gait deviations is required.

In this work, biomechanical analysis of a lower knee amputee with a conventional prosthetic limb (CPL) was performed using a software called ‘OpenSim’. The simulated gait cycle data with CPL is compared for the deviation in the gait cycle with a normal limb. Further on interpreting the simulated gait moments, a modified lower knee prosthetic limb (MPL) was proposed and further analysed in the software package.

Comparative percentage difference in moment variation for a subject with CPL and MPL to that of a normal person was observed to be 27.6 % and 6.4 % respectively for walking gait, and 1.38% and 0.37% respectively for running gait. Structural analysis carried out on the proposed prosthetic limb designed of TECAPEEK-MTCF-30 material yields a safety factor of 2.1, which is higher than 1.5 for a conventional prosthetic limb.

This method has a better probability of being employed for designing and improving the biomechanical and structural properties of customized prosthetic limbs. This study is a stepping stone for the fabrication and experimental analysis of a customized lower knee prosthetic limb with better comfort compared to conventional limbs.