Patients with medial collateral ligament injuries have painful swelling and limited movement of the medial knee and loss of walking function (unstable walking or increased pain). When the knee is externally rotated, the patient is in severe pain and often prevents the examiner from proceeding. If the patient is a simple medial collateral ligament injury, the general situation can be treated conservatively, from a medical point of view, if the medial collateral ligament tear reaches three degrees, especially the combined anterior and posterior cruciate ligament injury should be treated surgically, that is, if the ligament is completely ruptured, then take the surgical treatment method, in the clinic we found that many patients with second degree medial collateral ligament injury, using regular conservative treatment, the effect Very satisfactory. It is important to note that: 1) the affected knee should be fixed in time after the injury; 2) the medial side of the joint should be iced at an early stage; 3) a long leg brace should be worn for protection; and 4) the affected limb should not be weight-bearing when the knee can be taken out of bed with the help of crutches.