The shoulder is the most common type of dislocation in the human body. They almost always result from a trauma and can cause significant damage to the shoulder joint.
What is a Shoulder Dislocation?
A shoulder dislocation occurs when the humerus (upper arm bone) slides out of place from it’s usual location (the glenoid or “cup side”) on the shoulder blade. For the injury to be considered a dislocation the head of the humerus must slide completely off of the glenoid. In some cases people suffer shoulder subluxations which is when the humerus only slides partially off of the glenoid. Do you need physiotherapy for your dislocated or injured shoulder? Call us at 416-526-6933 or book online!
Three Types of Dislocations
Shoulder dislocations come in three varieties and are named for the direction that the humerus bone goes when it slides out of joint.
Anterior Dislocations – These are the most common type of shoulder dislocations and usually result from an arm that is externally rotated (twisted outward) in an elevated position – think of the position that a pitchers arm is in on a baseball card. In some cases a person will suffer an anterior dislocation from a fall on an outstretched arm. 95% of all shoulder dislocations are anterior dislocations.
Posterior Dislocations – Occur when the humerus slides off the glenoid backwards. These injuries can occur from a fall or from the very strong and unbalanced muscle contraction that happens when a person has a seizure or is electrocuted.
Inferior Dislocations – Occur when the humerus slides off the glenoid in a downward direction. These occur from the arm being pulled in a downward direction and are the most rare type of shoulder dislocation.
Relocating (“Reducing”) a Shoulder Dislocation
Shoulder dislocations must be handled with care by a trained professional. We do not recommend trying to ‘put your shoulder back in’ yourself following a dislocation. Patients can easily sustain further injury if a shoulder is reduced incorrectly. The proper reduction technique involves coaxing the shoulder into the right position using very little force and trying to relax the muscles surrounding the shoulder to allow the humerus to settle back into its proper position.
Injuries That Result From Shoulder Dislocations
Several structures can become injured when a shoulder is dislocated. We will go over the most common ones below;
Labral Tear – the cartilage structure that lines the glenoid (cup) of the shoulder is often damaged by the dislocation.
Bankart Lesion – this is an avulsion of an anterior portion of the bone of the glenoid that occurs as the humerus breaks free of the glenoid.
Hill-Sachs Lesions – this is an injury to the posterior aspect of the humerus bone that occurs from the forceful collision between the glenoid and the head of the humerus directly following an anterior dislocation.
Rotator Cuff Tears – tearing of the tendons that make up the rotator cuff is common as they are stretched forcefully during a dislocation.
Nerve Injuries – The nerves that go into your arm pass through the shoulder and can be damaged as a result of a shoulder dislocation. This is an uncommon but serious side effect. If you suffer a dislocation and you are experiencing a great deal of numbness, tingling and muscle weakness after the shoulder has been reduced, it may indicate some trauma to the nerves.
Do Shoulder Dislocations Need Surgery?
Most first-time shoulder dislocations do not require surgery. They will be able to rehabilitate the joint to regain full function with a well structured physiotherapy plan. However some patients may require a surgical consultation in more severe cases. If the patient experiences recurrent dislocations despite a good physiotherapy plan and those dislocations are occurring with less force each time it is an indication that the shoulder is unstable and may need a surgical procedure to tighten up the joint. A very large rotator cuff that is limiting arm function may also be a reason that a patient would undergo surgery following a dislocation. It is important to note that physiotherapy is the first line of defence in shoulder dislocations.
I Have Dislocated My Shoulder What Should I Do?
After your shoulder has been put back in place (this usually either happens spontaneously or in the emergency room guided by a physician) you will need a plan to get that shoulder back in top shape. Make an appointment to see an experienced physiotherapist as soon as possible to begin your rehab plan. After a dislocation, a shoulder that is left alone can become stiff or ‘frozen’ making it difficult to regain function, and a shoulder that is used too aggressively following dislocation is at risk of being left unstable and resulting in recurrent dislocations. So get that Physiotherapist on board as soon as possible. They are experts at returning patients to normal function after an injury of this type.
In the meantime, follow these tips to ensure the best possible outcome:
- Gentle movement is a good thing – very gently moving your shoulder through a partial range of motion with little or no force will help to ensure your joint does not become stiff.
- Ice the shoulder in the first few days to reduce pain and swelling. 2 or 3, 20-minute sessions with 30 min. In between several times per day will be sufficient.
- If you have numbness, tingling, weakness – go back to see the orthopaedic doctor.
- Support your arm. When seated have your arm supported by a sling or the armrest of a chair.
- Use a sling during the day until you see your physiotherapist who will assess the stability of the joint and thus whether or not you need to continue to use the sling.
- Stop sporting or other high-risk activity (gym workouts or other lifting). It may go without saying, but another fall or trauma to your shoulder at this time would be very bad.
- Remember that the vast majority of people will do very well if they follow their physiotherapy plan following a shoulder dislocation. Follow the tips above and get that plan started as soon as possible.