What is a dislocated shoulder?
A shoulder dislocation occurs when the round ball at the top of the upper arm bone, or humerus, leaves the socket in the shoulder blade, or scapula. That means the ball and socket bones of the shoulder are separated, with the ball of the humerus out of position.
Tissues that hold the bones together – including muscles, tendons that connect muscles to bones and ligaments that join the shoulder bone to the shoulder blade – are also sometimes injured. In addition, tearing of cartilage, a rubbery tissue that covers and protects the ends of bones, is possible.
A partially dislocated shoulder, or shoulder subluxation, means that only part of the upper arm bone is out of socket.
Why is the shoulder most likely to become dislocated?
The shoulder joint – a ball-in-socket mechanism, with the round top of the arm bone fitting into a groove in the shoulder blade – is the most mobile joint in the body. It can turn in several directions. Yet that mobility can leave the shoulder unstable, even though it’s anchored by muscles, tendons and ligaments. Of all the joints in the body, the shoulder is the most likely to become dislocated.
Symptoms and Causes
What can cause a shoulder dislocation?
A shoulder dislocation is usually caused by a fall or blow to the shoulder. This can happen during sports activities. Dislocated shoulders are more common in teens than younger children.
What are the symptoms of a dislocated shoulder?
Symptoms of a dislocated shoulder include:
- Extreme pain and/or weakness
- Bruising or redness
- Muscle spasms
- Numbness, tingling or weakness in the arm, hand or fingers
- Immobility of the arm, or difficulty moving it
- Shoulder visibly out of place
If you believe your shoulder is dislocated, take the following steps:
- Don’t move the arm, and keep it close to the body. Don’t try to jam the shoulder back into place, because that can damage blood vessels, muscles, ligaments and nerves.
- Apply an ice pack to the injured area. Ice can ease swelling and reduce pain.
- Take ibuprofen (Advil® or Motrin®), naproxen (Aleve® or Naprosyn®) or acetaminophen (Tylenol®) for pain. It’s always best to consult with a healthcare provider before taking pain medication, especially for patients with heart disease, high blood pressure or kidney disease, or if they’ve suffered from stomach ulcers or internal bleeding.
- Go to an emergency room or call 911.
Diagnosis and Tests
How is a dislocated shoulder diagnosed?
At the emergency room, tell the doctor how the suspected dislocation occurred, and if the shoulder was dislocated in the past.
The doctor may give muscle relaxers to reduce pain.
Among the tests the doctor may order include X-rays, a magnetic-resonance-imaging (MRI) scan to spot tissue damage or a computerized-tomography (CT) scan, which would reveal any broken bones not seen on the X-ray. The doctor might even find a dislocation simply by feeling the top of the arm bone.
Management and Treatment
How is a dislocated shoulder treated?
If a shoulder dislocation is diagnosed, the doctor will carefully place the arm bone back into the shoulder socket and into the correct alignment, a process called “closed reduction.” It’s closed because it doesn’t require surgery.
- If spasms haven’t started, the patient may not need pain medication. The doctor might sedate the patient and use a numbing agent for the shoulder. Once the shoulder is back in place, any severe pain stops almost immediately. The doctor will order another X-ray to make sure the reduction was successful.
- You may have to wear a splint or sling for at least a week to promote healing and minimize pain. The doctor may recommend icing the injured shoulder 3 or 4 times a day. You may need to do light exercises so your shoulder doesn’t tighten or freeze. After a few weeks, the injured shoulder will usually function normally again.
- About a week after the injury, the doctor will send the patient to an orthopedist, or bone specialist, who will check the shoulder’s bones, muscles, tendons and ligaments. After the shoulder heals, a physical therapist assigns exercises to stretch the shoulder and restore mobility. Later, the therapist adds exercises that strengthen the shoulder muscles and ligaments. This rehabilitation helps prevent future shoulder dislocations.
Check with the doctor before resuming activities – including sports, gardening, heavy-lifting or reaching above the shoulder – that would stress the shoulder.
Is surgery ever necessary for a dislocated shoulder?
Usually no surgery is necessary, especially if the shoulder was dislocated for the first time. The doctor may determine that surgery is needed if bones or tendons are injured. If the shoulder is dislocated more than once, which is more common among young athletes, doctors might surgically repair or tighten ligaments that keep the arm bone connected to the shoulder blade.
When should I call the doctor after treatment for a dislocated shoulder?
Call the doctor if there is swelling or pain in the shoulder, arm or hand that worsens over time, or if the arm or hand turns purple. A fever is another warning sign. If the injury doesn’t heal as expected, a doctor might order a scan to find tissue tears not seen earlier.
Is there a way to prevent shoulder dislocation?
Athletes can wear protective gear during sports activities. During play children and even adults should avoid tugging and pulling on the arms.
Outlook / Prognosis
What is the long-term prognosis for a shoulder dislocation?
Once a shoulder is dislocated, it’s more likely to feel unstable, or dislocate again. Further, the shoulder is easier to dislocate with each subsequent injury. The rotator cuff – a group of muscles and tendons surrounding the shoulder joint – are more likely to tear in older patients who have suffered shoulder dislocations. A brace can sometimes help if the condition becomes chronic. An orthopedist should keep an eye on older and chronic patients.