Persistent and severe shoulder pain, often due to dislocation of the shoulder joint. There is a clear history of trauma. All traumatic anterior shoulder dislocations have a clear history of trauma, shoulder pain, swelling and dysfunction, with the injured limb in an elastic fixed position of mild abduction and internal rotation, with the elbow flexed and the affected forearm supported by the healthy hand. It usually results from a history of trauma. Traumatic anterior shoulder dislocation has a clear history of trauma, shoulder pain, swelling and dysfunction, with the injured limb held in a mildly abducted internal rotation position with the elbow flexed and the affected forearm supported by the healthy hand. The appearance is a “square shoulder” deformity, with the shoulder crest protruding significantly and the subacromial hollow. The head of the humerus can be felt in the axilla, under the rostral process or under the clavicle. The injured limb was mildly abducted and could not be pressed against the chest wall, such as when the elbow was pressed against the chest, the palm of the hand could not touch the opposite shoulder at the same time (Dugas sign, i.e. positive shoulder hitch test). X-ray examination can clarify the type of dislocation and determine the presence or absence of fracture. The radiographic sign is a loss of normal parallelism between the two articular surfaces of the acromion, the glenoid and the humeral head that make up the shoulder joint. According to the degree and direction of separation of the humeral head, there are several types of dislocations as follows: 1. Semi-dislocation of the shoulder joint The joint gap is wide at the top and narrow at the bottom. The humeral head is shifted downward, with half of the humeral head still facing the shoulder pelvis. 2.Anterior dislocation of the shoulder joint is the most common. The sub rostral dislocation is particularly common. The humeral head overlaps with the shoulder pelvis and scapular neck and is located 0.5cm-1.0cm below the rostral process. The humeral head is externally rotated and the humeral stem is mildly abducted. Subclavian dislocation of the humeral head and subglottic dislocation are less common. 3. Posterior dislocation of the shoulder joint is rare. It is worth noting that the alignment between the humeral head and the shoulder glenoid is still good in the orthopantomograph and the joint gap exists, so it is easy to miss the diagnosis. Only in the lateral or axillary views can the humeral head be shown to be posteriorly dislocated and located posterior to the shoulder pelvis.