Development of dynamic models of the Mauch prosthetic knee for prospective gait simulation

Recent advances in computational modeling and simulation of human movement makes it possible to isolate and predict the potential contributions of a prosthetic device to the overall system performance. The Mauch S-N-S knee is one of the most widely used prosthetic knees in the market. The goal of this study is to develop dynamic models of the Mauch S-N-S knee for predictive simulation of a transfemoral amputee's gait under idealized conditions. Based on the functional description of the Mauch S-N-S prosthetic knee from the literature, a combined bench test and data fitting approach employing modified slow, normal, and fast gait patterns and nine combinations of stance and swing damping settings were performed. Two types of dynamic models, 2-phase and 4-phase models, of the Mauch S-N-S prosthetic knee were developed. The range of the coefficient of determination of the two dynamic models, when compared to the test data, was from 39.9 to 95%. Both dynamic models of this study can be utilized in musculoskeletal modeling studies, to better understand amputee gait and the contributions and interactions of various prosthetic leg components to the ambulatory performance.