RESUMEN
BACKGROUND: Knee braces have been shown to improve knee mechanics in the case of slow walking, but most studies lack the data regarding the effects of a brace on knee injury in the case of lack of movement. OBJECTIVE: Jumping, emergency stop, rotation which easily induce knee joint injury during the rapid exercise were simulated to investigate whether silicon mesh braces can provide stable support for the knee joint and provide data support for the protection against anterior cruciate ligament injury. METHODS: Twelve healthy subjects were selected to perform three movements: Squatting, one-leg jump and steering jump respectively with and without a brace. Reflection markers were placed on the feet, calves, thighs, and pelvis of the subjects. A Qualisys motion capture system was used to obtain kinematic data of the knee joints. Knee joint motion was compared between with and without a brace. This study was performed by Medical Ethics Committee of Guizhou College of Traditional Chinese Medicine on August 8, 2018 (approval No. 2018661). RESULTS AND CONCLUSION: There were significant differences in the angle and angular velocity of the knee joint among sagittal plane, coronal plane, and horizontal plane. The knee joint valgus and internal rotation angle were reduced when wearing a brace in particular in one-leg jump and steering jump. The angular velocity of horizontal surface rotation also decreased obviously when wearing a brace. These findings suggest that wearing a brace can affect the motion mechanics of the knee joint in the coronal and horizontal planes. This suggests that knee joint can effectively control the stability when wearing a brace in the process of dynamic movement, and wearing a brace can improve the control of knee peak valgus angular velocity and external rotation angular velocity, which can help effectively prevent anterior cruciate ligament injury of patients with anterior cruciate ligament defects.