A gliding or plane joint between the acromion and the acromial end of the clavicle.
The joint located between the outer extremity of the clavicle (collarbone) and the acromion (the prominent bony projection at the upper part of the shoulder blade) is known as the acromioclavicular joint.
Injuries to the acromioclavicular joint are infrequent and typically occur due to falls onto the shoulder. These injuries can lead to subluxation, which is an incomplete dislocation where the bones remain partially in contact. In rare cases, a complete dislocation may occur, causing a complete displacement of the bones with no contact between them.
In cases of subluxation, the synovium (joint lining) and the surrounding ligaments endure stretching and bruising, resulting in joint swelling and a slight misalignment of the bones. Dislocation, on the other hand, involves torn ligaments, more significant swelling, and pronounced bone deformity. In both situations, the affected joint is characterized by pain and tenderness, and shoulder movement becomes restricted.
The treatment for subluxation typically involves immobilizing the arm and shoulder by using a sling. If pain and tenderness persist, the joint may be injected with a combination of corticosteroid medication and a local anesthetic to provide relief.
In cases of acromioclavicular joint dislocation, the recommended treatment involves using strapping around the clavicle and elbow to realign the outer end of the clavicle. This strapping is typically maintained for approximately three weeks. In certain instances, surgical intervention may be necessary to correct the dislocation.