Dislocated shoulder

DEFINITION

A dislocated shoulder is an injury in which your upper arm bone pops out of the cup-shaped socket that’s part of your shoulder blade. The shoulder is the body’s most mobile joint, which makes it susceptible to dislocation.

If you suspect a dislocated shoulder, seek prompt medical attention. Most people regain full shoulder function within a few weeks. However, once you’ve had a dislocated shoulder, your joint may become unstable and be prone to repeat dislocations.

CAUSES

The shoulder joint is the most frequently dislocated joint of the body. Because it moves in several directions, your shoulder can dislocate forward, backward or downward, completely or partially, though most dislocations occur through the front of the shoulder. In addition, fibrous tissue that joins the bones of your shoulder can be stretched or torn, often complicating the dislocation.

It takes a strong force, such as a sudden blow to your shoulder, to pull the bones out of place. Extreme rotation of your shoulder joint can pop the ball of your upper arm bone out of your shoulder socket. Partial dislocation — in which your upper arm bone is partially in and partially out of your shoulder socket — also may occur.

A dislocated shoulder may be caused by:

• Sports injuries. Shoulder dislocation is a common injury in contact sports, such as football and hockey, and in sports that may involve falls, such as downhill skiing, gymnastics and volleyball.
• Trauma not related to sports. A hard blow to your shoulder during a motor vehicle accident is a common source of dislocation.
• Falls. You may dislocate your shoulder during a fall, such as from a ladder or from tripping on a loose rug.

SYMPTOMS

Dislocated shoulder signs and symptoms may include:

• A visibly deformed or out-of-place shoulder
• Swelling or bruising
• Intense pain
• Inability to move the joint

Shoulder dislocation may also cause numbness, weakness or tingling near the injury, such as in your neck or down your arm. The muscles in your shoulder may spasm from the disruption, often increasing the intensity of your pain.

When to see a doctor

Get medical help right away for a shoulder that appears dislocated.

While you’re waiting for medical attention:

• Don’t move the joint. Splint or sling the shoulder joint in its current position. Don’t try to move the shoulder or force it back into place. This can damage the shoulder joint and its surrounding muscles, ligaments, nerves or blood vessels.
• Ice the injured joint. Applying ice to your shoulder can help reduce pain and swelling by controlling internal bleeding and the buildup of fluids in and around your shoulder joint.