The Effects of Polycentric Knee Design and Alignment on Swing Phase Gait Parameters: A Simulation Approach

Conclusions

This study shows that polycentric knees, which generally perform better than single-axis knees with improved stance stability and ease of push-off, can also perform well during swing in terms of knee extension before heel contact and foot clearance throughout swing. The extended moment arm for the weight of the shank and foot due to the superior location of the IC in polycentric knees is the reason for the improved swing performance of polycentric knees. Appropriate placement of the socket adapter, which affects A/P alignment, is crucial so that foot clearance during swing is not compromised. The insights obtained from the study would be useful in developing simpler polycentric knees, which can extend completely without any extension assist if proper alignment is used as recommended.

Clinical Relevance

The study provides better understanding of the effects of polycentric knee placement and the need for an extension assist during the swing phase of walking, which could help clinicians improve the selection of appropriate knees and their alignment for prosthesis users.

Source: JPO Journal of Prosthetics and Orthotics - September 22, 2021 Category: Orthopaedics Tags: ORIGINAL RESEARCH ARTICLES Source Type: research