Shoulder dystocia is often referred to as 50 shoulder or “frozen shoulder”. The prevalence is about 5% in the general population and 20-30% in the bilateral population. Patients with diabetes and abnormal thyroid function are particularly prone to develop frozen shoulder. It starts with persistent pain in the shoulder joint, followed by a gradual decrease in the range of motion of the joint or even inability to move it, and a significant number of patients have pain at night. Although it is possible for “frozen shoulder” to heal on its own, it often takes 1 to 2 years, and some functional limitations often remain. Taking the right treatment for frozen shoulder as early as possible can shorten the course of the disease and relieve the pain. In the early stages of the disease, non-surgical treatment is used to gradually restore the function of the shoulder joint by relieving pain and improving the range of motion of the joint. If non-surgical treatment is not effective, minimally invasive shoulder arthroscopy can be used to restore function in most patients. Rotator cuff injury and impingement syndrome is a degenerative disease that occurs in people after the age of 40, especially in people over 55. It is characterized by pain in the shoulder joint, difficulty sleeping, inability to lie on the affected side, reduced strength and even difficulty moving the shoulder joint, and in some cases, difficulty even carrying a glass of water. Rotator cuff injuries are highly variable, and different treatments should be chosen according to the different conditions of rotator cuff injuries. Non-surgical treatment is the treatment of choice for most rotator cuff injuries and includes pain relief, rest, moderate functional exercises, and muscle strength exercises started at the appropriate time. If short-term non-surgical treatment does not work or if symptoms continue to worsen, surgical treatment is required. Minimally invasive arthroscopic rotator cuff repair is the ideal treatment. After surgery, the pain disappears and the joint function improves significantly. Calcific tendonitis This condition is not very common, but those who have it often have sudden, severe shoulder pain. A radiograph of the shoulder joint may show foci of calcification within the rotator cuff. The pain originates from the calcified foci that are disintegrating. Conservative treatment may include hormone injections and functional rehabilitation. In some patients, the symptoms will disappear quickly, while in others, the pain will be secondary to shoulder clotting due to prolonged pain. Patients for whom conservative treatment is not effective are suitable for shoulder arthroscopy, which is minimally invasive and provides rapid postoperative recovery and pain relief, reducing the risk of chronic shoulder pain and shoulder condensation. Shoulder arthritis The incidence of shoulder arthritis is low, but there are multiple causes that can lead to shoulder arthritis. When chronic shoulder pain persists without relief, a radiograph should be taken to look for arthritis. Secondary arthritis following a fracture of the proximal humerus often results in severe pain and limited range of motion. Most patients can improve their symptoms with conservative treatment. If the arthritis continues to worsen, resulting in unbearable pain and limited shoulder function, shoulder replacement surgery may be considered. Post-operative pain relief and improved function greatly improve quality of life.