[In vivo study on the body motion during the Shi's cervical reduction technique with 3D motion capture]

The clinical effect of the Shi's cervical reduction technique for cervical spondylosis and related disorders has confirmed, however, there were few studies on the body motion during manipulation in vivo study. This study is to summary the law of motion and the motion characteristics of the right operation shoulder, elbow, knee and ankle joints by data acquisition and analysis with the 3D motion capture system.

The markers were pasted on the head, trunk, left and right acromion, elbow joint, wrist joint inner side and the outer side of the inner and the outer side and the lateral upper arm, forearm lateral, anterior superior iliac spine, posterior superior iliac spine, trochanter, femoral and tibial tubercle, inner and outer side of knee, ankle, fibular head, medial and lateral in first, 2,5 metatarsal head, heel and dual lateral thigh the calf, lateral tibia of one manipulation practioner, and the subject accepted a complete cycle of cervical "Jin Chu Cao and Gu Cuo Feng" manipulation which was repeated five times. The movement trajectory of the practioner's four markers of operation joints were captured, recorded, calculated and analyzed.

The movement trajectories of four joints were consistent, while the elbow joint had the biggest discrete degree. The 3D activities of the shoulder and elbow were more obvious than other two joints, but the degree of flexion and extension in the knee was significantly greater than the rotation and lateral bending.

The flexibility of upper limb joint and stability of lower limb joint are the important guarantees for the Shi's cervical reduction technique, and the right knee facilitated the exerting force of upper limb by the flexion and extension activities. The 3D model built by the motion capture system would provide a new idea for manipulation teaching and further basic biomechanical research.