A shoulder dislocation occurs when the head of the humerus (upper arm bone) pops out of the shallow shoulder socket of the scapula (called the glenoid). This can happen when a strong force pulls the shoulder upward or outward, or from an extreme external rotation of the shoulder joint.
There are two types of dislocation:
Partial dislocation–The head of the humerus slips out of the socket momentarily and then snaps back into place. (Also called subluxation.)
Full dislocation–The head of the humerus comes completely out of the socket.
Causes
Shoulder dislocation can be caused by:
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Falling on an outstretched arm
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A direct blow to the shoulder area, such as in automobile accident
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Forceful throwing, lifting, or hitting
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Force applied to an outstretched arm, such as in a football tackle
Risk Factors
A risk factor is something that increases your chance of getting a disease, condition or injury.
Risk factors for a shoulder dislocation include:
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Previous shoulder dislocation or subluxation
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Participating in contact sports such as football, wrestling, and hockey
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Ehlers-Danlos syndrome (a condition involving loose joints)
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Poor muscle tone
Symptoms
Symptoms include:
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Pain, often severe
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Instability and weakness in the shoulder area
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Inability to move the shoulder
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Swelling
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Bruising
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Shoulder contour appears abnormal
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Numbness and tingling around the shoulder or in the arm or fingers
Diagnosis
The doctor will ask about your symptoms, how the injury occurred, and examine the injured area. Diagnosis is based on the physical exam of your shoulder area. The doctor may do an x-ray to rule out a related fracture or damaged surrounding soft tissues and to see in which direction the shoulder is dislocated.
Treatment
Do not try to force the bones back into place. Seek medical care immediately. Delaying treatment increases the chance of permanent damage to the shoulder joint.
Treatment includes:
Closed Reduction–The doctor will move the head of the humerus back into the shoulder joint socket by applying traction to your arm. You will be given pain medication before this procedure begins.
Immobilization–After the reduction, you will need to wear a sling or a device called a shoulder immobilizer to keep the shoulder from moving. The shoulder is generally immobilized for three weeks and full recovery takes several months.
Rest–It is important to rest your shoulder and not put any strain on the joint area.
Ice and Heat–Apply ice or a cold pack to your shoulder for 15-20 minutes, four times a day, for the first two days. After the 3rd day, use a heating pad for 20 minutes or less might help relief muscle soreness. This helps reduce pain and swelling as well. Wrap the ice or cold pack in a towel. Do not apply the ice directly to your skin.
Rehabilitation Exercises–After removal of the should sling, begin exercises to restore strength and range of motion in your shoulder as recommended by your healthcare professional.
Pain Medications–Nonsteroidal anti-inflammatory drugs (NSAIDs) or acetaminophen (Tylenol) helps pain relief.
Surgery–Surgery is rarely needed for a first time dislocation. It is often needed for a shoulder that dislocates repeatedly.
Prevention
To help prevent a shoulder dislocation:
RESOURCES:
American Academy of Orthopaedic Surgeons
http://www.aaos.org
The American Orthopaedic Society for Sports Medicine
http://www.sportsmed.org
References:
American Academy of Orthopaedic Surgeons website. Available at: http://www.aaos.org.
National Institute of Arthritis and Musculoskeletal and Skin Diseases website. Available at: http://www.niams.nih.gov/.
