Effects of total hip replacement on knee joint motion / 中国组织工程研究

ABSTRACT

BACKGROUND: Human lower limb system under different motion statuses exhibits great difference in terms of kinetic characteristics and joint deformation magnitude. Total hip replacement has been shown to be the best method to solve the severe illness of hip joints today. A good understanding of the responses of human lower limb system, in particular the knee joint, following total hip replacement is significant for rehabilitation training of patients.OBJECTIVE: To analyze the effects of total hip replacement on knee joint deformation during motions by comparing the data collected from a patient who underwent total hip replacement 19 months ago and a healthy control subject under the same testing environment and method.METHODS: The patient was measured through the use of Optotrak Certus motion capture system (Northern Digital Inc.,California), and simultaneously measurements were performed in a healthy control subject presenting with similar body weight and body mass. Measurement indices included step length, step frequency, joint corner, and joint displacement curves. Speed and acceleration of each joint were calculated based on measured data.RESULTS AND CONCLUSION: Following total hip replacement, the structure of natural hip joint was destroyed. Although the gait did not change greatly, experimental data showed that knee joint deformed more greatly than normal gait, indicating the self-accommodation of human body, i.e., increasing the loading and deformation magnitude of knee joints can avoid the injuries caused by hip joint surgery.