The shoulder joint is known as a ‘ball-and-socket’ joint. The ball is the rounded top of the bone in the upper arm, which fits into the socket; the cut-shaped outer part of the shoulder blade. When the top of the humerus moves out of its usual location in the shoulder joint, the shoulder is said to be dislocated. In some cases, a shoulder is dislocated when the arm is pulled or twisted with extreme force in an outward, upward, or backwards direction. This extreme force pops the top of the humerus out of its socket. In other cases, a shoulder dislocation is the result of a fall on an outstretched arm, a direct forceful blow to the shoulder, a seizure, or a severe electric shock. Seizures and shock can cause shoulder dislocations because they produce extreme, unbalanced muscle contractions that can wrench the humerus out of place.
Overall, a shoulder dislocation can occur in several directions:
- Anterior dislocation – is when the humeral head moves toward the back of the body – usually caused by a hit during an athletic event, electric shock, or seizure. However, posterior partial dislocations are very common in athletes such as weightlifters.
- Inferior dislocation – occurs the least often; accounting for only 0.5% of shoulder dislocations and results in a downward movement of the humeral head. This type of dislocation can be caused by weight or force being applied to the arm as it is extended away from the body.
Causes & Symptoms
A traumatic event, such as a blow to the shoulder or a fall, is the most common cause of a first-time shoulder dislocation. The resulting dislocation is nearly always an anterior dislocation, in which the humeral head moves out the socket to the front of the body.
These symptoms are commonly associated with shoulder dislocations, including the following:
- A sensation of the shoulder (or popping out of place) – at the time of occurrence, followed by the appearance of deformity in the shoulder. The shoulders may not look symmetrical, and the bulge of the humeral head may be visible beneath the skin next to the shoulder for slimmer individuals.
- Severe pain – is felt immediately when the dislocation occurs. Pain may be felt in the upper arm and shoulder. Pain can be aggravated by movement if movement is still possible.
- Muscle spasms – in the shoulder can occur following a dislocation; this can add to the pain. Muscle spasms also can make it very difficult to return the dislocated humeral head to its normal position. For this reason, physicians may provide medication to relax the patient’s muscles before restoring the shoulder into position.
- A sudden decrease in shoulder mobility – may be experienced after a dislocation. In fact, movement may not be possible at all. Even if movement is possible, it may not be recommended because nearby nerves, tissues, and / or blood vessels could be damaged.
- Bruising and swelling – in the shoulder and upper arm, which develops shortly after the injury occurs.
- Numbness – may be felt in the arm, hand, neck, and / or fingers.
Who Gets a Shoulder Dislocation?
Shoulder dislocations most commonly occur in teenage boys and young men in their 20s because they tend to engage in physical activities that raise the risk for dislocation, such as playing a contact sport like hockey, football or rugby. Sports that have potential for frequent or high-impact falls, such as gymnastics or downhill skiing, can raise risk too. Outside of sports, car accidents and falls are often causes of a dislocated shoulder. An epileptic seizure and electrocution can also trigger a posterior dislocation, as muscles in the front of the shoulder contract forcefully. Shoulder dislocation is also a common complication after a stroke as a result of paralysis on one side of the body.
In addition to participation in contact sports, there are three factors that can make the shoulder joint more vulnerable to dislocation:
Repetitive overhead movement
Repetitive shoulder motion can cause the ligaments surrounding the shoulder’s socket to stretch. Weakened and stretched shoulder tissue from repetitive movement can leave the shoulder joint less stabilized, which may lead to shoulder instability. Shoulder instability due to repetitive use is sometimes referred to as a ‘micro-traumatic dislocation’.
A previous dislocation
After the first dislocation, the shoulder is much more vulnerable to a recurring dislocation; especially for younger patients. In fact, some estimates show that patients younger than 20 have a recurrence rate of up to 90%. The first dislocation can stretch the tissues surrounding the shoulder joint, causing the shoulder to be unstable and result in another dislocation. The medical term for repeated shoulder dislocations is called ‘chronic shoulder instability’.
Some people naturally have more connective tissues in the body, including those who may be referred to as “double-jointed.” They may experience a shoulder dislocation without substantial injury or pain. These people may also be more likely to experience partial dislocations, in which the joint slides back into place by itself.
How Does It Affect You? How Serious Is It?
Traumatic shoulder dislocations are very painful. You may have a traumatic shoulder dislocation if you ever experience an injury to the shoulder and notice:
- Swelling or bruising of the shoulder
- Your shoulder is visibly out of place
- You are unable to move the shoulder
- Nerve damage
- Tearing of the muscles and / or tendons of the shoulder
- Fractures of the shoulder
- Recurrent shoulder dislocations or subluxations
If you have experienced a traumatic shoulder dislocation, you are more susceptible to shoulder dislocations in the future. Your chance of developing recurrent shoulder dislocations is related to the age of your first dislocation. For example, if your first shoulder dislocation occurs when you are very young, you have a higher chance of developing recurrent dislocations. However, if your first shoulder dislocation occurs at an older age (over 40 years old), your chances of developing recurrent instability are much lower.
Recommended Treatment & Rehabilitation
Most dislocations are anterior dislocations, in which the humeral head moves out of the socket to the front of the body; its diagnosis is fairly straightforward. However, a rarer type of dislocation is frequently overlooked by physicians – posterior dislocations account for only 2-4% of shoulder dislocation but are often initially misdiagnosed. Diagnosing a shoulder dislocation normally involves a thorough medical history and physical examination. Imaging tests can also be taken to confirm a diagnosis.
During a medical history portion of the examination, the physician will ask the patient questions about the following:
- The incident that caused the injury
- Symptoms, and how they impact activities
- Medical history and history of any shoulder injuries or treatment
The physical evaluation for a dislocated shoulder typically consists of palpation and observation, as well as a range of motion and strength tests, as described below:
- Palpation and observation – The physician touches the injured shoulder, noting areas of tenderness and observing abnormalities. For example, there may be a bump visible at the front of the shoulder.
- Range of motion and strength tests – There are many physical tests a physician may use to help diagnose a shoulder dislocation. During these tests, the physician may note a person’s range of motion and degree of shoulder rotation.
Based on the physical examination, the physician will be able to make a diagnosis or will order medical imaging to get more information. If the physician wishes to perform an imaging test to confirm the diagnosis, an X-ray is nearly always sufficient. Occasionally an MRI or CT scan may be used to identify damage to nearby tendons, ligaments, or other soft tissues.
Treatment usually begins with non-surgical methods, such as wearing a sling, a brace, and physiotherapy. Surgery may be considered if shoulder instability persists. The physician may recommend one or more of the following non-surgical treatment options, including:
- Immobilization – Immediately after reduction, the arm should be immobilized in a sling for 1-3 weeks to prevent shoulder movement. Range of motion exercises for the hand and wrist can still be done at this time.
- Ice application – Ice can be applied 3-4 times each day to the injured shoulder. Doing so can help reduce pain and swelling.
- Anti-inflammatory medications – Non-steroidal anti-inflammatory medications such as ibuprofen or aspirin may also help decrease inflammation and pain.
- Physical rehabilitation – A physician or physiotherapist usually creates a rehabilitation program catered towards the patient’s needs and goals. This is a critical part of the recovery process that helps restore shoulder function and movement by strengthening the muscles surrounding the shoulder joint.
Here are some examples of exercises for you to try. It is recommended to take breaks from exercising these methods if you start to have pain:
Lie on your back, holding a wand or stick with your hands. Your palms should face down as you hold the wand. Place your hands slightly wider than your shoulders. Keeping your elbows straight, slowly raise your arms over your head until you feel a stretch in your shoulders, upper back, and chest. Hold this position 15-30 seconds, then repeat 2-4 times.
Shoulder blade squeeze
While standing with your arms at your sides, squeeze your shoulder blades together. Do not raise your shoulders as you are squeezing. Hold this stretch for 6 seconds, then repeat 8-12 times.
Internal rotator strengthening
Begin by tying a piece of elastic exercise material to a doorknob. Afterwards, stand or sit with your shoulder relaxed and your elbow bent 90 degrees. Your upper arm should rest comfortably against your side. Squeeze a rolled towel between your elbow and your body for comfort and to help keep your arm at your side. Hold one end of the elastic band in the hand of the painful arm. Rotate your forearm towards your body until it touches your belly. Finally, keep your elbow and upper arm firmly tucked against the towel roll or the side of your body during this movement.
Stand against a wall with your feet about 12-14 inches away from the wall. If you feel any pain when you perform this exercise, stand closer to the wall. Place your hands on the wall slightly wider apart than your shoulders, and lean forwards. Gently lean your body toward the wall, then push back to your starting position. Once finished, repeat this exercise 8-12 times.
Shoulder external rotation
Stand with your affected arm close to a wall. Bend your arm up so your elbow is at a 90-degree angle and turn your palm as if you are about to shake someone’s hand. Then, hold your forearm and elbow close to the wall. Finally, press the back of your hand into the wall with moderate pressure. Hold for a count of 6 before repeating the exercise 8-12 more times.
Alternative & Homeopathic Treatment
It is recommended to try these steps at home to help ease discomfort and encourage healing after being treated for a dislocated shoulder:
- Rest – Do not repeat any activity that has caused your shoulder to dislocate and try to avoid painful movements. Limit heavy lifting or overhead activity until your shoulder has fully recovered.
- Apply ice then heat – Applying ice on your shoulder helps reduce inflammation and pain. Use a cold pack, a bag of frozen vegetables, or a towel filled with ice cubes for 15-20 minutes at a time. After two or three days, when the pain and inflammation have improved, hot packs or a heating pad may help relax tight and sore muscles. Limit each application to 20 minutes at a time.
- Pain relievers – Over-the-counter medications, such as aspirin, ibuprofen, or acetaminophen, may help relieve pain.