When the shoulder slips out of joint and the ball of the humerus (upper arm bone) is no longer resting in the socket of the scapula, the joint is said to be dislocated. When the joint partially slips out of the joint, but returns on its own, it is called subluxation. Shoulder dislocation is coupled with extreme pain at the time of injury, with visible deformity, swelling and possibly bruising. The patient will lose function of the shoulder and have pain with movement.
A dislocated shoulder can be caused by traction type injuries to the arm, falls and violent muscle contractions (like in pitching and throwing). Because the shoulder joint is very mobile, it is always at increased risk for injury. Specifically, factors that increase the risk of dislocation are contact sports such as football, hockey, wrestling, and basketball, repeated shoulder sprains, arthritis and muscle weakness leading to an unstable and unsupported joint.
The joint can dislocate in the forward, backward or downward direction, however the most common dislocation is a forward (anterior) displacement.
It is important that the examining physician know how the injury happened to accurately assess the extent of damage to the surrounding tissues, muscles, blood vessels, and nerves. An X-ray may be ordered.
The best thing about a shoulder dislocation is that pain is completely relieved once the joint is put back into place with a reduction maneuver.
A sling may be necessary for several weeks following a dislocation. Ice the sore area 3-4 times a day. It is very important to prevent future dislocations of the shoulder. This can be done with strength and range of motion exercises. If it becomes a repeated experience a brace can help, however, it is sometimes necessary to repair or tighten torn or stretched ligaments to help support and stabilize the shoulder joint with surgery.