A tear of the posterior horn of the medial meniscus of less than second degree is not particularly serious. When it is second degree and above, the condition is relatively serious. Posterior horn tears of the medial meniscus are a very common clinical injury and are most commonly associated with acute trauma, prolonged exertion, and repetitive stress stimulation. Symptoms of posterior horn meniscus tear will appear pain, popping, cross-locking, joint degeneration and other manifestations. After a patient has injured the posterior horn of the medial meniscus, it is important to perform the appropriate tests, and MRI is commonly used for evaluation, which can show increased signal in the area of the posterior horn of the meniscus, or even signs of a tear. When the posterior horn of the meniscus is torn, the tear is less than second degree and relatively minor and can be treated conservatively. When the tear is more than second degree, it is relatively severe, and patients who reach third degree often have to consider surgical treatment options. After the patient’s diagnosis is clear, the patient should be braked and rested in the acute stage, and some medicines that activate blood circulation and improve circulation can be used to promote the repair of the meniscus. After tearing the posterior horn of the meniscus, it is necessary to cooperate with the doctor’s guidance for treatment as early as possible. After gradual improvement through treatment, excessive pressure on the knee should be avoided in the subsequent life.