Shoulder Instability
(Dislocating Shoulder)

The shoulder is a complex ball and socket joint. It is made up of the humerus (upper arm), scapula (shoulder blade), and clavicle (collarbone). Shoulder instability occurs when the humeral head no longer lines up with the glenoid (socket).

Shoulder instability occurs most commonly from severe injury or trauma. This can result in injury to the labrum, known as a Bankart lesion. Some patients without trauma may never have a dislocation have looser joints resulting in shoulder instability. This is called multidirectional instability.

Evaluation includes a history of symptoms, a physical examination, x-rays for bone injury, and specialized physical exam maneuvers. Specialized maneuvers are used to help determine the extent of instability. An MRI may be done to evaluate the labrum, capsule, and cartilage surfaces for damage.

Treatment is based on examination, imaging, and pain. Initial treatment is aimed at strengthening shoulder-stabilizing muscles. Arthroscopic surgical treatment to repair a torn labrum or tighten the shoulder capsule is indicated based on the extent in instability, nature of injury, age, and activity level. Occasionally, in those with a large bone defect or recurrent instability despite previous surgical treatment, an open surgery may be recommended to reconstruct the bone loss, known as a Laterjet procedure. Surgery is done as an outpatient and return to activities generally occurs around 3 months.