A shoulder dislocation occurs when the ball of your upper arm bone (humerus) is forced fully out of its normal position on the shoulder socket (glenoid labrum).
A shoulder dislocation is usually associated with extreme pain and an inability to move your arm until it is relocated back into the socket.
Shoulder subluxation is a partial dislocation, when the shoulder joint comes part way out before relocating almost immediately.
Shoulder dislocation and subluxation can occur as a result of a sudden trauma or from underlying shoulder joint instability.
What causes shoulder dislocation?
Your shoulder is the most mobile joint in your body. It has an amazing range of motion. Your shoulder allows you to lift your arm overhead, out to the side, rotate it behind your head and your back and reach in multiple directions. However this huge range of motion comes at the cost of its stability.
Most common causes of shoulder dislocation/instability.
1. Traumatic Shoulder Dislocation
High speed or traumatic shoulder dislocation occurs when your shoulder is in a vulnerable position and is popped out at speed. Commonly this is with your arm out away from the body. This type of mechanism is common when dislocating the shoulder in a football tackle or during a fall.
2. Repetitive Shoulder Ligament Overstrain
People who are prone to having looser ligaments (hypermobile) in their shoulders can dislocate their shoulders with relative ease. This increased passive shoulder instability is sometimes just the normal make-up of your shoulder. Sometimes, it is the result of repetitive over-stretching of the shoulder joint through sports such as swimming, tennis, throwing sports (cricket, baseball etc) and volleyball that require repetitive overhead motion and overstretch the shoulder ligaments and joint capsule.
Looser shoulder ligaments mean your shoulder’s rotator cuff muscles have to work harder to maintain the stability of your shoulder. If you have an unstable shoulder, the best thing that you can do to prevent or help rehabilitate your shoulder dislocation is to undertake a specific shoulder rotator cuff strengthening program under the guidance of your Leading Edge Physiotherapist.
3. Multi-Directional Instability
In a small number of patients, their shoulder is unstable in multiple directions due to their genetic pre-disposition to have naturally loose ligaments throughout the body and may be “double-jointed” or hypermobile. In these patients, the shoulder may feel loose or dislocate repeatedly in multiple directions. This is called multi-directional instability.
Due to their genetically elastic collagen fibres in their ligaments, these patients typically do not respond with much success to surgical stabilisation. They are best managed with a thorough shoulder stabilisation strengthening program which needs to be carefully prescribed by a Leading Edge physiotherapist.
How is a shoulder dislocation treated?
Both acute (first time) and repeated shoulder dislocations are normally treated initially with a period of non-operative rehabilitation guided by your physiotherapist. Occasionally, if this exercise-based treatment fails and the shoulder continues to remain unstable, surgical stabilisation may be considered.
Treatment often follows the following pathway:
Immediate reduction of the dislocation by a trained health professional
X-rays and scans to check the success of the reduction and to check the extent of damage to the shoulder
Relief of pain and swelling with rest, physiotherapy treatment and medication
Regain mobility and strength of the shoulder with specific exercises prescribed by your physiotherapist
Sport-specific exercises to allow the return of normal movement patterns for your sport
Prevention exercises prior to return to sport
Taping and bracing to help provide extra support on return to sport
What results can I expect after my shoulder dislocation?
After the first time you dislocate or sublux your shoulder, recurrence is very likely, especially in younger patients, due to the damage done to the supporting ligaments of the shoulder. 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 to reduce the recurrence rate by allowing some initial healing.
Resumption of sport can differ between individuals, but 6 to 8 weeks after injury is normally the minimum time out of sport and three months is probably safer to avoid re-dislocation.
Despite immobilisation treatment, the recurrence range is still fairly high. If your shoulder is not immobilised after a dislocation, the chances of re-dislocation 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 an exercise program specific to your shoulder provided by your Leading Edge Physiotherapist.
I've just dislocated my shoulder, what should I do right now?
To help your injury resolve as fast as possible:
Get the dislocation reduced and x-rayed by a qualified medical professional
Rest your arm in a sling until you see your Leading Edge Physiotherapist
Use ice packs for 15 – 20 minutes regularly
Hug a pillow or rest your arm on a pillow during the night.