Comparative Efficacy of Transfemoral Prosthetic Interfaces: Analysis of Gait and Perceived Disability

Abstract

Introduction The High-Fidelity (HiFi) interface is an emerging transfemoral interface technology. However, no comparison of this interface to traditional transfemoral interface designs is currently available. The purpose of this study is to measure the effects of the HiFi system on gait and perceived disability compared with a traditional socket design in a subject with transfemoral amputation. Methods The subject was first tested with a traditional ischial containment socket, then fit with the HiFi system, and tested again after a 30-day accommodation period. Three-dimensional motion analysis was performed using an 8-camera Vicon Motion Capture system. The Oswestry Low Back Pain Disability Questionnaire v2.0 and Western Ontario and McMaster University Osteoarthritis index were administered at initial and secondary testing to evaluate perceived disability. A one-way analysis of variance and Fischer's least significant difference were used to determine statistical difference between conditions. The level of significance for all tests was set at P ≤ 0.05. Results Notable results included an increase in self-selected gait velocity, prosthetic hip adduction, and hip extension. Reductions in lateral center of mass deviation during gait and in perceived disability was also shown with use of the HiFi condition. Discussion This study analyzed the effects of the HiFi Interface System on biomechanical parameters of gait and perceived disability compared with a baseline IRC condition in this elderly subject with history of TF amputation. Several improvements and markers of increased stability with use of the HiFi were noted. Perceived disability was also greatly improved comparatively. Conclusions The HiFi Interface System presented some biomechanical advantages to traditional IRC socket designs in this case, which may allow for increased stability in patients utilizing a TF prosthesis. Further research with larger samples is warranted.

Transfemoral Prosthetic Socket Designs: A Review of the Literature

“…32,33,41,43 Socket suspension methods were recorded in nine articles. Of these three used common suction socket (CSS), 33,35,37 three operated vacuum-assisted suspension (VAS), 21,40,42 one used both CSS and passive suction, 38 one used both VAS and passive suction, 34 and one used both CSS and VAS. 41 Four articles omitted which suspension method was used, 32,36,39,43 and auxiliary suspension was not reported in any of the articles.…”

“…The IC socket has the largest evidence base as it features in all 13 articles. The CAT-CAM design was tested in five articles 21,33,34,40,42 ; one article tested the CAT-CAM, NSNA, and narrow ML designs, 32 whereas the other seven referred to IC generically.…”

“…The HiFi was found to be superior to IC in both studies. 42,43 There is a lack of standardization in measurement of subjective perception that precludes comparisons among articles. Consequently, both studies support the suggested benefits of the compression/release technique.…”

“…Of the articles, four compared quad, 32,33,36,37 one compared quad and MAS, 38 one compared MAS, 39 four compared subischial, 21,34,40,41 and two compared HiFi. 42,43 No articles were found regarding the Socketless Socket. All tables are therefore ordered first by intervention (quad, MAS, subischial, and HiFi) and second by year of publication in descending order.…”

“…The HiFi socket has been reported in two articles 42,43 between 2016 and 2017. Both articles compared HiFi against an IC socket.…”