Comminuted patella fracture, after going to the hospital for regular treatment healing, rehabilitation exercises, the full function of the patella is not much affected, most cases can achieve a normal bending angle (135 ° ~ minus 10 ° or so). The main function of the knee joint is to straighten and bend, and the mobility of a normal person’s knee joint is generally about 135° to minus 10°. The main function of the patella is to act as a lever, which can largely reduce the force of knee extension. After regular treatment and rehabilitation exercises for comminuted patellar fracture, in most cases there is no effect on the mobility of the knee joint. However, it is worth noting that when the patella fracture must be regular examination and treatment, and after the operation must be regular rehabilitation exercise. Surgery only ensures that the fracture is repaired, but rehabilitation is essential to overcome knee stiffness and maximize mobility.