A hip disarticulation prostheses test system to simulate gait for prostheses evaluation

BACKGROUND: The limited number of hip prostheses users makes it less feasible to conduct amputee tests for prosthesis development in the clinic, which restricts the development efficiency of the intelligent prostheses. OBJECTIVE: This study proposes a hip disarticulation prostheses test system (HDPTS) to supplement the amputee tests for hip disarticulation prosthesis (HDP) evaluation, which would potentially facilitate the prosthesis evaluation safety and development efficiency. METHODS: The hip trajectory of an individual with normal gait was acquired and reproduced by calculating the corresponding movement joint angle of a manipulator. Then, an HDP was fit on an amputee and on the HDPTS respectively to obtain the hip and knee joint angles of the HDP during walking. Comparing the root mean square error (RMSE) of the expected and planned trajectory, the joint angles between the amputee test and HDPTS test, to verify the feasibility and accuracy of the HDPTS for prosthesis evaluation. RESULTS: The RMSE between the expected and planned trajectory value was less than 1.20 mm (< 0.19%). The RMSE of the joint angles between the amputee test and HDPTS test were 2.18ffi (1.8%) and 3.13ffi (5.92%) for hip and knee joint respectively. CONCLUSION: The HDPTS was found accurate in hip trajectory reproduction and feasible in gait simulation for the prosthesis evaluation, which could potentially supplement the amputee test for prosthesis design thus improving prosthesis test safety and development efficiency.