Abstract: BACKGROUND: Gait analysis, as a radiation-free dynamic assessment method, may be able to assist imaging to evaluate patients with scoliosis, thereby reducing radiation exposure.
OBJECTIVE: To analyze the correlation between gait parameters and imaging parameters in adolescent idiopathic scoliosis patients, and preliminarily explore the potential mechanism through OpenSim simulation modeling.
METHODS: Twenty adolescent idiopathic scoliosis patients aged 10-18 years with Cobb angle of 10°-45° were selected as adolescent idiopathic scoliosis group. The control group was normal children of the same age and the same body mass index range, and a total of 40 subjects were included. The differences in spatiotemporal parameter, kinematic parameters, dynamic parameters, and gait deviation index of the two groups were compared to explore the correlation between pathological gait and coronal balance. The related mechanisms were preliminarily studied.
RESULTS AND CONCLUSION: (1) The comparison of gait parameters between groups showed that the percentage of bilateral support phase and double support phase increased in adolescent idiopathic scoliosis patients, and the percentage of bilateral swing phase decreased (P < 0.05). The maximum adduction angle of the left hip joint of patients in the adolescent idiopathic scoliosis group was greater than that of the control group, and the maximum abduction angle of the bilateral hip joints was significantly less than that of the control group (P < 0.05). The ankle joints of the two groups when the bilateral heels initially touched the ground; the difference between angles was significant (P < 0.05). The peak power of right hip flexor muscle group in adolescent idiopathic scoliosis patients was significantly decreased when they pushed off the ground (P < 0.05). (2) The results of the correlation study showed that the maximum abductive angle of the right hip joint was significantly positively correlated with the Cobb angle (r=0.552, P=0.012), and the right peak power of right hip flexor muscle and C7 lateral offset were significantly negatively correlated (r=-0.475, P=0.034). There was a significant positive correlation between ankle angle and lateral pelvic tilt when left foot followed the ground (r=0.476, P=0.034). (3) The simulation results of muscle length showed that the change of muscle fiber length of gluteal medium muscle in adolescent idiopathic scoliosis patients was significantly reduced (P < 0.05). The change of muscle fiber length of the bilateral internal oblique muscle was significantly reduced in adolescent idiopathic scoliosis patients (P < 0.05). Comparing the muscle fiber length of the two groups when foot followed the ground, it was found that the muscle fiber length of the calf triceps of the adolescent idiopathic scoliosis patients was significantly shorter when foot followed the ground (P < 0.05). (4) The results showed that the postural stability control of the trunk of adolescent idiopathic scoliosis patients was decreased, which was manifested as slow step frequency, increased percentage of double support phase and decreased percentage of swing phase. The common pattern of low foot striking pattern is caused by bilateral Achilles tendon tension. In adolescent idiopathic scoliosis patients, the ability of hip flexor muscle to do work is decreased, which may be related to joint angular velocity and main bend direction. 

中国组织工程研究杂志出版内容重点：人工关节；骨植入物；脊柱；骨折；内固定；数字化骨科；组织工程

Key words: adolescent idiopathic scoliosis, gait parameter, gait deviation index, coronal balance, OpenSim, muscle parameter, imaging, three-dimensional gait analysis