HealthInfo Canterbury

Unstable shoulders & dislocations

Ngā pokohiwi pāhekeheke me ngā pakokitanga

Your shoulder joints (also called your glenohumeral joints) are the most mobile joints in your body. They're ball and socket joints, but the sockets aren't deep enough to hold the balls securely.

Because of this, your upper arm bone can move partially or completely out of its socket. If it moves partially out, it's called subluxation (sub-lux-ay-shun), but if it moves completely out, it's called dislocation.

Your shoulder joints can dislocate forwards (called anterior dislocation) or less commonly backwards (called posterior dislocation).

An accident that causes severe force to or over rotation of your shoulder can cause a dislocation. For example, falling from a ladder while holding on, a collision during a contact sport or a car accident. But if you're more flexible than average or have had a shoulder dislocate before, it can dislocate with simple movements like rolling over in bed.

Anterior dislocation doesn't happen much in children but is common in 18- to 25-year-olds, often resulting from sports injuries. It's also quite common in older people who may have less stable shoulder joints because their muscles are wasting and who are also more likely to fall.

If you have an unstable shoulder, you can do some exercises at home that will help. A physiotherapist can advise you on the best ones for you.

Symptoms of a dislocated shoulder

If you've dislocated your shoulder, you'll usually be able to see and feel that your shoulder is out of place. You'll feel severe pain and be unable to move your shoulder. You may also notice numbness or tingling in your neck or down your arm.

If you think you've dislocated your arm, you need to see a doctor immediately.

Diagnosing a dislocated shoulder

The doctor will ask what happened and examine your shoulder, arm and neck. They'll usually do an X-ray to make sure nothing is broken before they put the shoulder back into the right place.

Treating a dislocated shoulder

You'll need your shoulder put back into the right place. This is usually done under sedation or a general anaesthetic. If you've broken your shoulder as well as dislocated it, you might need surgery to fix the pieces back into the right place. An orthopaedic surgeon will do this.

Once your shoulder is back in place, you'll need to have your arm in a sling for one to two weeks. Your general practice team or physiotherapist will let you know how long you need to wear it for. While you have the sling, you should wear it all the time (including at night) and underneath your clothes for at least the first few days.

After that, when you aren't wearing the sling, let your tissues heal by taking care for six weeks to avoid lifting your arm in the way that dislocated it. Take extra care when showering, bathing and dressing.

It will take 12 to 16 weeks for your shoulder joint to heal fully. During that time, you should avoid any throwing movement if your shoulder dislocated forwards, or exercises like press-ups, burpees or planks if your shoulder dislocated backward. Also avoid any contact sports and activities that could put stress on your shoulder until your doctor or physiotherapist says it's OK.

Getting help for a dislocated shoulder

You should see a physiotherapist who can help you get full movement and strength back and get you back to what you were doing before your accident.

ACC may be able to provide help while you aren't fit for work, such as home help or taxis to appointment as well as work compensation payments.

Written by a Canterbury physiotherapist. Adapted by HealthInfo clinical advisers. Last reviewed July 2022.

Sources

Page reference: 35483

Review key: HISHI-13267