There are a variety of conditions that cause shoulder pain, but “frozen shoulder” is the most commonly known. The concept of “frozen shoulder” was first mentioned in the late 19th century when doctors believed that inflammation around the shoulder joint caused changes in the tissues within the shoulder joint such as degeneration and adhesions, resulting in pain and limited movement of the shoulder joint. The concept, nomenclature and mechanism of “frozen shoulder” have been discussed and modified over and over again. Up to now, the concept of “frozen shoulder” has been gradually blurred and replaced by more precise diagnoses, such as frozen shoulder, rotator cuff injury, rotator cuff injury, biceps longus tendinitis, etc. 1. Frozen shoulder: A type of adhesive capsulitis that causes stiffness of the glenohumeral joint, characterized by pain around the shoulder joint and limited movement in all directions. It used to be called “frozen shoulder”. The etiology of frozen shoulder is unknown, and it has a typical staging and tendency to heal on its own, ranging from a few months to several years. It accounts for about 10% of the causes of shoulder joint pain. 2.Shoulder impingement: Due to degeneration of the shoulder joint, formation of subacromial bony redundancy and bursal hyperplasia, the gap under the shoulder peak becomes smaller, resulting in shoulder joint pain caused by rotator cuff extrusion and impingement when abducting or lifting the arm. It can occur at any age, mostly in middle-aged and elderly people. Rotator cuff injury: It is a tearing injury of the rotator cuff tissue around the humeral head, and the main cause is the acromion impingement sign. Long-term impingement of the rotator cuff leads to degeneration of the rotator cuff, a decrease in the quality of the tendon, and eventually an injury tear. Or trauma to the rotator cuff on the basis of rotator cuff degeneration, resulting in rotator cuff injury. 4, biceps long head tendonitis: due to repeated physical exertion leads to biceps long head tendon wear and tear and causes tendon sheath congestion, edema and other inflammatory changes. It occurs in middle-aged people and is mainly characterized by shoulder pain, but no restriction of movement in the direction of external rotation of the shoulder joint. The most important diagnostic tool for sports medicine disorders is clinical physical examination, combined with medical history and other ancillary examinations such as imaging. For patients with shoulder pain, clinicians need to understand the concept, characteristics, imaging manifestations of the related diseases causing shoulder pain and the items and positive significance of the physical examination of the shoulder joint in order to avoid misdiagnosis and missed diagnosis. Shoulder arthroscopy for shoulder pain Shoulder arthroscopy emerged in the early 20th century and developed slowly in the early years, but in the last 20 years it has become a global phenomenon. Its advantages have gradually been recognized by orthopedic surgeons, and it is now the most important surgical route for the treatment of shoulder pain-related disorders. 1. Frozen shoulder: Shoulder arthroscopy is mostly used for the treatment of frozen shoulder to resolve the leftover shoulder joint dysfunction. Shoulder arthroscopy is used to release the contracted joint capsule and clean up the inflamed and edematous bursa, thus restoring a certain degree of shoulder mobility. 2.Shoulder impingement sign: Shoulder arthroscopic acromioplasty is the standard technique for treating shoulder impingement sign and has been widely used in clinical practice. It mainly includes: removal of the subacromial bursa wall, severing or partially severing the rostral shoulder ligament, polishing the anterolateral part of the acromion, and exploring and polishing the subacromial bursa. The purpose is to reduce the pressure on the subacromial space, but the amount of bone redundancy to be polished should be carefully grasped in order to achieve the best surgical results. 3.Rotator cuff injury: Rotator cuff injury is classified according to the degree of injury and whether it needs to be treated surgically. After arthroscopic exploration, the rotator cuff injury should be repaired with double or single row anchor nails to reconstruct the force coupling, and the tissue structure in the shoulder joint should be thoroughly examined. Because rotator cuff injuries are often associated with other shoulder disorders such as acromioclavicular impingement or biceps longus tendonitis, they need to be treated together during the arthroscopic procedure. Arthroscopic rotator cuff repair has excellent clinical efficacy and high patient satisfaction. 4. Hydroxylamine biceps long head tendonitis: Shoulder arthroscopic surgery should be considered for patients with biceps long head tendonitis whose long-term conservative treatment is ineffective, depending on the specific situation. There are two main types of surgery: arthroscopic biceps long head tendonotomy and rotational tendonotomy. Clinical studies have shown that young patients may be more suitable for transposition, which sacrifices little biceps strength but can meet the demands of regular exercise; whereas tendonotomy can be performed in elderly patients to reduce pain and improve quality of life.