Four months after the clavicle fracture surgery, the cause of arm muscle atrophy may be incorrect rehabilitation training or rehabilitation training intensity is not enough to cause, the treatment is still rehabilitation training, followed by physical therapy can be selected to assist. 1. Rehabilitation training: shoulder joint mobility training and muscle strength and endurance training. A simple criterion for shoulder mobility training is that the healthy shoulder joint on the opposite side can be used as a control. It includes shoulder extension and flexion, rotation, etc. Most of the muscle strength and endurance training is resistance training, which is mainly the active contraction of large muscle groups such as biceps and triceps. 2. Physiotherapy: It mainly includes heat therapy, massage, fascia gun, deep microwave, electric stimulation, etc. Physiotherapy can be used as an auxiliary means of treatment for rehabilitation training, aiming at increasing the blood circulation of muscles, accelerating metabolites discharge, loosening the adhesion of the fascia, and relieving the tension and fatigue of muscles, etc. Patients with the same disease have different physical conditions, so they may not have the same physical condition. For the same disease, patients with different physical conditions and different stages of the disease have different treatment methods, and should be standardized under the guidance of doctors.