康复学报 (Jan 2024)
Tibiofemoral Joint Contact Force Estimation Based on OpenSim Musculoskeletal Modeling
Abstract
ObjectiveA full-body musculoskeletal model is developed based on OpenSim, which has a knee joint structure with double contact points and three degrees of freedom, and to estimate the knee joint load, so as to provide the reliable basis for precise diagnosis of the patients with knee osteoarthritis and formulation of customized rehabilitation plan in clinic.MethodAuthorized public data set from Stanford university, published by the Shiley Center for Orthopaedic Research & Education at Scripps Clinic in La Jolla, California, was used to collect four subjects who had been undergone the total knee arthroplasty and implanted the pressure testing equipment. Based on the general musculoskeletal model gait2392 in the OpenSim model library, the tibial-femoral joint is adjusted from a single contact point to a double contact point, and the knee joint structure is adjusted to have three directional degrees of freedom. Through the model scale, inverse kinematics, inverse dynamics analysis, residual reduction processing and muscle control and analysis, medial/lateral tibiofemoral contact force is estimated during walking gait, considering the contribution of external force and internal muscle strength. MATLAB 2018b is used for statistical analysis. The effectiveness of the musculoskeletal model established in this study is verified by comparing the model estimation results with the measurement results of the implanted prosthesis.ResultsThe average correlation between the estimated contact force and the measured value of medial, lateral, and total contact force were 0.921±0.079, 0.817±0.084, and 0.930±0.066, and the average root square error were 0.336±0.146 BW, 0.332±0.146 BW, and 0.442±0.160 BW. The root mean square error of the estimated and measured peak contact force of the medial and lateral sides were 0.43±0.25 BW and 0.34±0.24 BW, and the errors at the time of peak contact force onset were 44.09±34.66 ms and 67.52±61.19 ms. Compared with the imimplanted pressure testing equipment, the tibiofemoral joint contact force estimation method based on OpenSim muscle bone modeling could accurately predict the medical, lateral and total contact forces of the knee joint.ConclusionThe established full-body OpenSim musculoskeletal model of the knee joint with two contact points and three degrees of freedom can be used to generate muscle-driven gait simulation and obtain reliable contact forces of the tibiofemoral joint, which provides an important basis for accurate monitoring of tibiofemoral joint load, formulation of clinical rehabilitation programs and continuous improvement of prosthesis design.
