 No muscles are directly involved in this injury, only ligaments; However, strengthening the hip flexor and hip extensor muscles may help alleviate the injury.The medial collateral ligament, posterior cruciate ligament, anterior cruciate ligament, and lateral collateral ligament are the four primary ligaments of the knee.The medial and lateral collateral ligaments primarily provide support to varus and valgus forces whereas the anterior and posterior cruciate ligaments prevent anterior and posterior translation of the tibia on the femur.