The shoulder is the most mobile joint in the body. Due to this, it is also the most frequently dislocated joint. The shoulder can dislocate in many directions, but anterior instability is by far the most common. Shoulder instability can range from subluxations – partial shoulder dislocations where the joint does not come completely out of the socket – to true shoulder dislocations, where the joint comes apart completely and remains in the dislocated position until it is reduced, or put back in joint. In some cases, the shoulder can dislocate posteriorly, although this is much less common than the anterior shoulder dislocations.
How it happens
Shoulder dislocations are usually caused by trauma. The trauma may involve a sporting injury, a motor vehicle accident or a fall. For anterior shoulder dislocations, the arm is usually away from the body, sometimes with the hand overhead. For posterior dislocations, the arm is usually in front of the body, reaching forward.
How it feels
Shoulder dislocations can be extremely uncomfortable when they occur. Generally, when the shoulder is reduced, or placed back in joint, the pain improves significantly. For some patients, shoulder dislocations are not very uncomfortable, while for others it can be extremely painful. Some patients are able to put their shoulder back in joint on their own, while others require medical attention in order for their shoulder to be reduced. For patients in whom the shoulder dislocations become recurrent, they may limit their activities to avoid further dislocations.
How it is fixed
In general, surgery is required to prevent shoulder dislocations, once the dislocations have become recurrent. Patients who are young and who participate in contact athletics are at very high risk of recurrence even after a first shoulder dislocation. In such individuals, surgery may be considered after the first dislocation. The surgery involves repairing the torn ligaments to the bone, and in some cases, also tightening (or shortening) the ligaments of the shoulder to prevent the shoulder from dislocating. The surgery can be done arthroscopically or using an open approach. The selection of the technique for surgery depends on the type of pathology or injury involved. The surgery is usually done arthroscopically.
After surgery, the arm is kept in a sling for three to four weeks. Some gentle exercises may be started during this time. When the sling is discontinued, more aggressive physical therapy is undertaken to restore motion and strength. Full return to athletics in all sports is generally at six months following the surgery.