Effect Of The Jumper’s Knee On The Jumping Movement Of Volleyball Players

Jumper’s knee is one of the most common injuries, especially in basketball, volleyball, and other athletes in the high jump. Researches have shown that jumper’s knee with no effect on the height of jump, athletes with this injury only appear compensatory actions, but there is no consistent conclusion. The purpose of this study is to identify the action characteristic of volleyball athletes with jumper’s knee, to find out the possible biomechanical mechanism of compensatory action, and to make reasonable recommendations targeted special training for the jumper’s knee treatment, rehabilitation and prevention of subsequent damage. Methods:In this study, we choose two groups of volleyball players, one group of people with jumper’s knee and the other one with healthy players. Make this two groups of players take run-up jump and dorp-jump tests. By comparing kinematics and dynamics index of two groups, analyse the action technical characteristics of the athletes with jumper’s knee. Also, through the comparison of movement between the health side leg and the injury side leg, analyse the compensatory action.Conclusions:1.Jumper’s knee significantly affect the jumping ability of volleyball players,reduce the propelling speed, and ultimately affect the jump height.2. Jumper’s knee can significantly affect the movement technology of volleyball players, reduce the knee flexion range and outreach range, the knee is not fully stretched when pedalling out from the ground. This is protective action of the athletes with jumper’s knee to reduce knee pain in the jumping process.3. Because of the affected knee movement, athletes with jumper’s knee showed compensation techniques in the hip and ankle joint through the jumping process. Increased hip outreach range can compensate for the dec lined knee range of outreach. Advanced propelling ankle can compensate for the declined knee extension.4. In both run-up jump and dorp-jump test, the vertical propelling impulse of volleyball players with jumper’s knee is smaller than the healthy group, propelling impulse and braking impulse of injury group in antero-posterior drection are also smaller.