Shoulder Dislocation

Introduction

A dislocation is is an injury to a joint in which the ends of the bones are forced from their normal positions. The shoulder is a “ball-and-socket” joint where the “ball” is the rounded top of the arm bone (humerus) and the “socket” is the cup (glenoid) of the shoulder blade. A layer of cartilage called the labrum cushions and deepens the socket. A shoulder dislocation occurs when the humerus pops out of its socket, either partially or completely. As the body’s most mobile joint, able to move in many directions, the shoulder is most vulnerable to dislocation. A shoulder dislocation may be caused by a sports injury, trauma from a motor vehicle accident or a fall.

Symptoms of Shoulder Dislocation

Dislocation causes pain and unsteadiness in the shoulder. The shoulder may be visibly deformed or look out of normal placement. Other symptoms of a dislocated shoulder may include:

• Swelling
• Numbness
• Weakness
• Bruising

The muscles in the shoulder may spasm and cause tingling sensations in the neck and down the arm. Complications of a shoulder dislocation may also include muscle tears, tendon or ligament injuries, and blood vessel or nerve damage.

Diagnosis of Shoulder Dislocation

A shoulder dislocation is diagnosed through a physical examination and a review of symptoms. Additional diagnostic tests may include:

• X-ray
• MRI scan
• Electromyography

The electromyography test is used to determine whether there is any nerve damage as a result of the shoulder dislocation.

Treatment of Shoulder Dislocation

In most cases, the dislocated shoulder can be manipulated back into place by a doctor in a process known as closed reduction. When the shoulder bone is back in place, severe pain normally subsides. The arm and shoulder are then immobilized in a special splint or sling for several weeks as the shoulder heals. Medication may also be prescribed for pain. A shoulder that is severely dislocated or in cases where surrounding ligaments or nerves have been damaged, surgery may be necessary to tighten stretched ligaments or reattach torn ones.

After treatment for a shoulder dislocation, when pain and swelling have subsided, physical therapy is recommended to restore the range of motion of the shoulder, strengthen the muscles, and prevent future dislocations. After treatment and recovery, a previously dislocated shoulder may remain more susceptible to reinjury, potentially resulting in chronic shoulder instability and weakness.