Shoulder pain is common among middle-aged and elderly people, and the first reaction of many people is frozen shoulder. There are many causes of shoulder pain, and the most common are the following diseases: acromioclavicular impingement syndrome, rotator cuff injury, subacromial bursitis, biceps longus tendonitis, frozen shoulder, and even cervical spondylosis. The following is an introduction to each of these diseases: 1. Shoulder impingement syndrome Shoulder impingement syndrome is the most common cause of shoulder pain. It is caused by the compression of the shoulder tendon by the shoulder peak after the upper arm is raised. The main symptoms are: chronic dull pain in the shoulder, increased pain during supination or abduction activities, and reduced upper arm strength if there is a tendon tear. If left untreated, rotator cuff injury will develop. This type of patient can be braked by suspending the forearm with a triangular scarf or sling in the morning, and the pain can be significantly relieved by local closure. Oral anti-inflammatory and analgesic medications can also promote edema and relieve pain, while physical therapy can also be used. If there are pathological changes such as tendon rupture and tendon disruption, arthroscopic minimally invasive surgery is recommended. If shoulder impingement can be diagnosed in time, the cause and pathological changes can be clarified, correct treatment can be given, the disease progression can be slowed down, and thorough treatment can generally achieve a more satisfactory result. Rotator cuff injury is mainly caused by trauma (e.g., sudden abduction of the shoulder joint or sprain when falling and landing on the ground or holding a heavy object), degenerative changes in rotator cuff tissue, and chronic impingement of the rotator cuff (often occurs during repeated sports that require extreme abduction of the shoulder joint, such as baseball, backstroke and butterfly, weight lifting, and racquet sports). The injured shoulder should be adequately rested and the muscles of the healthy side of the shoulder should be strengthened. Avoid pushing and pressing movements and replace them with pulling activities. Topical medications such as creams can be used locally. For more severe pain, take oral non-steroidal anti-inflammatory painkillers. If the injury is severe and the rotator cuff is completely torn, or if conservative treatment does not work well for 3-6 months, surgery is required. With the development of arthroscopic technology, most of the surgical treatments for rotator cuff injuries are now minimally invasive under arthroscopy, and the results are better. 3, subacromial bursitis Mostly caused by trauma, shoulder tendon injury or degeneration, long-term extrusion and stimulation, serious cases can be complicated by significant limitation of shoulder joint activities. It is usually characterized by pain, restricted movement and limited pressure pain. The pain is progressively worse, with more pain at night and more pain with movement, especially during abduction and external rotation (compression of the bursa). Treatment in the acute stage includes rest, anti-inflammatory and analgesic drugs, physiotherapy, acupuncture and placing the affected limb in the abducted and externally rotated position, and local closed injections are effective. In addition to the above treatments, the chronic phase should emphasize rehabilitation without increasing the pain and mainly restoring the motor function of the shoulder joint. For those who are ineffective by conservative treatment, surgery can be considered. 4.Biceps long head tendonitis It often occurs in people who repeatedly overactivate for a long time, and can develop acutely after trauma or strain, but mostly as a result of degenerative changes in the tendon due to long-term wear and tear. The main clinical manifestations are: pain in the anterior part of the shoulder joint, which may radiate to the anterolateral part of the upper arm, intensifying at night, aggravated by shoulder activity, and improving after rest. In the acute stage, the pain is severe and it is difficult to put on or take off clothes. At first, there is no obvious restriction of shoulder joint activity, but pain during abduction, posterior extension and rotation. The pain gradually worsens and the shoulder joint activity is limited. In the first stage, you can apply safflower oil and other blood-activating and anti-swelling drugs, apply ointment, and take non-steroidal anti-inflammatory drugs orally. In severe pain, the forearm can be suspended by a triangular scarf to avoid overuse of the shoulder joint. Local physiotherapy or hot compresses can help the inflammation subside, and local closure therapy can be done if necessary. For individual cases of recalcitrant biceps longus tendonitis, surgical treatment is feasible. 5. Adhesive capsulitis This is what we usually call frozen shoulder. The pain can spread to the neck and upper extremities. When the shoulder is bumped or pulled by chance, it can cause severe pain like tearing, and the shoulder pain is light day and heavy night. The movement of the shoulder joint can be limited in all directions, especially in combing the hair, dressing, washing the face, forking the waist, etc. In severe cases, the function of the elbow joint can also be affected. Patients are afraid of the cold in their shoulders, and many of them use cotton pads to wrap their shoulders all year round, and even in summer, they are afraid to blow on their shoulders. Currently, the treatment of frozen shoulder mainly relies on oral anti-inflammatory and analgesic drugs, physical therapy, local closure of painful spots, massage and tui-na, self-massage and other comprehensive therapies, as well as joint function exercises. Chronic adhesion dysfunction can be treated by applying arthroscopic release and strengthening functional exercises after surgery, which is more effective. 6. Cervical spondylosis This is not a disease of the shoulder joint, but another major type of disease, which needs to be examined by a specialist and then treated symptomatically. It is because of the multi-causal nature of shoulder joint pain that rehabilitation treatment is needed under the guidance of a specialist, never exercise blindly, otherwise it will not only make the condition more serious and complicated, but also add difficulties to the subsequent treatment.