ABSTRACT
Objective To investigate ISO 7206 standard used as a guidance for clinical selection of total hip prosthesis. Methods Kinematics and dynamics process of normal walking gait was simulated by establishing a numerical musculoskeletal model; the corresponding finite element model of total hip prosthesis was constructed, and gait loads were applied to calculate stress distribution on prosthesis, which were compared with that on ISO finite element model. ResultsPeaks of hip joint reaction forces were achieved at 20% gait and 54% gait during normal walking gait, which were used as gait loads for finite element simulation, and the results showed that the maximum Von Mises stress of prosthesis was reached at 20% gait. The maximum Von Mises stress of prosthesis in loosening model was higher than that in non-loosening model, and some differences existed in the distribution pattern. The maximum stresses of prosthesis both under ISO loads and gait loads by different body weights were analyzed and compared, and the maximum stress of prosthesis under ISO loads was equivalent to that under gait loads by body weight between 108 kg and 142 kg. ConclusionsThe prosthesis that passed ISO test can meet the strength requirement for normal gait loads of 100 kg body weight.