A dislocated shoulder happens when your upper arm (humerus bone) separates ‘pops out’ of your shoulder socket (glenoid fossa). The shoulder is one of the easiest joints to dislocate because the ball joint of your upper arm sits in a very shallow socket. This makes the arm extremely mobile and able to move in many directions, but also means it is not very stable.
The above X-ray shows a dislocated shoulder joint
In some cases, the surrounding tissues supporting the shoulder joint may also be overstretched or torn (this can considerable complicate recovery and may pre-dispose you to re-occurrence). A dislocated shoulder takes between 12 and 16 weeks to heal after the shoulder has been put back into place, if all runs smoothly.
You can dislocate your shoulder if you fall on to your arm heavily. Most people dislocate their shoulder while playing a contact sport, such as rugby, or in a sports-related accident. In older people, the cause is often falling on to outstretched hands – for example, after slipping on ice. Shoulder dislocations can happen more easily in people who are highly flexible, such as those with loose joints (joint hypermobility).
In most cases of dislocated shoulder, the ball part of the joint pops out in front of the shoulder socket. It’s much more unusual for the bone to pop out of the back of the shoulder joint. This can happen after an epileptic fit or an electrocution injury, and is less easy to spot.
Dislocated shoulder signs and symptoms may include:
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.
Go to your nearest accident and emergency (A&E) department immediately if you think you have dislocated your shoulder. Do not try to pop your arm back in yourself – you could damage the tissues, nerves and blood vessels around the shoulder joint.
While waiting for medical help, avoid moving your upper arm as much as possible. You could try placing something soft, such as a folded blanket or pillow, in the gap between your arm and the side of your chest to support it. If you can, ask someone to make a simple sling to hold your lower arm across your chest, with the elbow bent at a right angle.
You’ll be assessed and examined when you get to A&E. You’ll usually have an X-ray to check whether you’ve broken any bones and confirm the dislocation. If you have a fracture, you may have further scans to investigate the area in more detail. Fractures with a shoulder dislocation require specialist Orthopaedic care, and you may need surgery. If you do not have any fractures, your arm will be gently manipulated back into its shoulder joint using a procedure known as reduction.
You’ll be given painkillers and may be offered medicine to help you relax (a sedative). Reduction is usually carried out in A&E, but sometimes it’s done in the operating theatre under general anaesthetic (where you’re unconscious) by the orthopaedic team. While you’re sitting on the bed, the doctor will rotate your arm around the shoulder joint until it goes back in its socket. This may take a few minutes.
Some people tear ligaments, tendons and other tissues when they dislocate their shoulder. If these tissues have been damaged, you may need surgery to repair them. This can significantly reduce the chance of dislocating the same shoulder again in the future for some people. Surgery to repair shoulder tissues is often done using keyhole surgery, where small cuts (incisions) and a thin tube with a light and camera at one end (arthroscope) are used.
Sometimes it’s necessary to have open surgery to move bones around in the shoulder to prevent further dislocations. Surgery can sometimes be avoided by doing appropriate exercises to strengthen the shoulder if the tissues are overstretched but not torn.
After the first time you dislocate or sublux your shoulder, recurrence is very likely, especially in younger patients. The recurrence rate in patients under 25 years old is about 80%. The recurrence rate decreases as your age advances. Because of the high recurrence rate, the goal of any treatment is to reduce the possibility of a recurrent dislocation.
The minimum treatment for the first time dislocation should be immobilisation in a sling for 2 to 3 weeks to take advantage of the off-chance that it will reduce the recurrence rate. This is basically to let everything tighten back up in the shoulder. Resumption of athletic activities can be taken up on an individual basis, but 6 to 8 weeks after injury is a minimum and three months is probably safer to avoid redislocation.
Despite immobilisation treatment, the recurrence range is still fairly high. If your shoulder is not immobilised after a dislocation, the chances of redislocation are extremely high with unrestricted activity in the first three weeks. Once your shoulder dislocates a second time, it will almost always continue to re-dislocate with the arm in certain positions and often with less and less trauma on each occasion. Your best chance to avoid re-dislocation is to immobilise your shoulder in a sling and undertake a physiotherapist prescribed exercise program specific to your shoulder.
When the head of your shoulder dislocates, the capsular ligaments are overstretched. If the glenoid labrum, which attaches your capsule to the rim of the shoulder socket is torn, it is known as a Bankart lesion. If a Bankart lesion exists, you are more likely to require surgical stabilisation.
A Hills-Sach fracture occurs when the humeral head impacts against the rim of the shoulder socket resulting in a depression fracture in the humeral head. The fracture will normally increase your pain but does not normally require surgery as it is stable. It can, however, increase your likelihood of future shoulder dislocation.
These injuries will normally rehabilitate successfully with a supervised shoulder exercise program. A small percentage require surgical stabilisation if there are repeat dislocations
Surgical shoulder stabilisation is sometimes necessary to repair torn or overstretched ligaments, repair Bankart lesions etc and prevent a future shoulder dislocation. With surgery, the chances of recurrent dislocation for all patients overall are about 5%.
You will advised whether this option is suitable for you after discussions between your doctor and physiotherapist have assessed your shoulder and analysed your response to non-operative treatment. Your physiotherapist will provide you with a progressive and recovery appropriate strengthening plan to address your shoulder dislocation/instability. Pure Physiotherapy works with leading shoulder specialists to provide assessment and diagnosis, non-operative and post-operative shoulder rehabilitation programs.
If you have any questions about your shoulder, please ask your Physiotherapist.
The chances of dislocating your shoulder again will depend on your age and how well the tissues surrounding the joint healed the first time. It can help if any torn tissues were surgically repaired after the dislocated shoulder was put back in place. However, subsequent dislocations do sometimes occur, particularly in people younger than 25 and those over 40.
Doing regular recovery exercises under the supervision of a physiotherapist and avoiding awkward arm positions can also reduce the risk of dislocating your shoulder again.
Ban, I, Troelsen, A, Christiansen, DH, et al. Standardised test protocol (Constant score) for evaluation of functionality in patients with shoulder disorders. Dan Med J. 2013;60(4).
Bankart, AS, Cantab, MC. Recurrent or habitual dislocation of the shoulder-joint. Clin Orthop Relat Res. 1993;291:3–6
Eshoj, H, Bak, K, Blond, L, et al. Translation, adaptation and measurement properties of an electronic version of the Danish Western Ontario Shoulder Instability Index (WOSI). BMJ Open. 2017;7(7)