Shoulder dislocation is a very common traumatic injury across a wide range of sports. In most cases, the head of the humerus (upper arm bone) is forced forwards when the arm is turned outwards (externally rotated) and held out to the side (abducted). This causes an anterior dislocation, which make up approximately 95% of all shoulder dislocations.
Types of Dislocation:
Anterior (forward) - Over 95% of shoulder dislocation cases are forward. Most anterior dislocations are sub-coracoid. Sub-glenoid; subclavicular; and, very rarely, intrathoracic or retroperitoneal dislocations may occur. It can result in damage to the axillary artery and nerves around the shoulder.
Posterior (backward) - Posterior dislocations are occasionally due to electrocution or seizure and may be caused by strength imbalance of the rotator cuff muscles. Posterior dislocations often go unnoticed, especially in an elderly patientand in the unconscious trauma patient.An average interval of 1 year was discovered between injury and diagnosis of posterior dislocation in a series of 40 patients.
Inferior (downward) - Inferior dislocation is the least likely form, occurring in less than 1% of all shoulder dislocation cases. This condition is also called luxatio erecta because the arm appears to be permanently held upward or behind the head.It is caused by a hyper abduction of the arm that forces the humeral head against the acromion. Inferior dislocations have a high complication rate as many vascular, neurological, tendon, and ligament injuries are likely to occur from this kind of dislocation.
- The injury is usually acute, caused by direct or indirect trauma such as a fall or forced abduction and external rotation.
- There is a sudden onset of severe pain, and often a feeling of the shoulder 'popping out'.
- The shoulder will often look obviously different to the other side, usually loosing the smooth, rounded contour.
- The patient will usually hold the arm close into their body and resist abducting and externally rotating the shoulder.
- If there is any nerve or blood vessel damage there may also be pins and needles, numbness or discoloration through the arm to the hand.
- There is usually quite severe pain associated with a dislocation.
Dislocations in younger people tend to arise from trauma and are often associated with sports or falls. Older patients are prone to dislocations because of gradually weakening of the ligaments and cartilage that supports the shoulder.
Anterior dislocations often occur when the shoulder is in a vulnerable position. A common example is when the arm is held over the head with the elbow bent, and a force is applied that pushes the elbow backward and levers the humeral head out of the glenoid fossa. This scenario can occur with throwing a ball or hitting a volleyball. Anterior dislocations also occur during falls on an outstretched hand. An anterior dislocation involves external rotation of the shoulder; that is, the shoulder rotates away from the body.
Posterior dislocations are uncommon and are often associated with specific injuries like lightning strikes, electrical injuries, and seizures. On occasion, this type of dislocation can occur with minimal injury in the elderly, and often the diagnosis is missed in this case.
There is a strong likelihood that you will need some rehabilitation to help you regain both the function of the shoulder, and to prevent it from dislocating again. Some cases may even require surgery if the shoulder is regularly dislocating, or if there is an associated fracture. Generally dislocations are reduced under anaesthetic. After the reduction you will be advised to wear a sling to rest and immobilise the shoulder for about 2 weeks. If there are complications such as fractures or soft tissue damage, you may need additional treatment and longer immobilisation. medication is necessary to control pain and swelling. After the period of initial immobilisation you need physiotherapy to regain movement and to strengthen the rotator cuff muscles which support the shoulder joint to prevent reoccurrences.
Surgery is sometimes necessary following a shoulder dislocation if there has been extensive damage to muscles, tendons, nerves, blood vessels or the labrum. Surgery is then usually performed as soon as possible after the injury. In cases of recurrent shoulder dislocations, surgery may be offered in an attempt to stabilise the joint. There are a number of procedures which can be performed. The procedure can be either a key hole surgery or an open technique. In both the principle of surgery remains the same, i.e. re-attaching the torn labrum back to the rim of the bony socket . Usually tiny screws called ‘anchors’ are used to achieve this suture. Well done procedure either open or arthroscopc should give good result to the patient by preventing any further dislocations.
Healthy Joint Club says:
‘Stability’ is important in the leg, and ‘Mobility’ is important for the hand (upper limb). Shoulder joint has the highest freedom of movement. But when a patient is afraid of the very movement for which the shoulder is known, due to the fear of that joint getting dislocated, he or she lost the very basic function of that joint. Yet young people who suffer from repeated dislocations of this joint tend to neglect and leave it for long which results in structural damage to the bones of the joint which is not reversible. So please seek advice at least after the second dislocation.