Hajer Ali Sarah Sameer

What is dislocation of the shoulder? What causes a shoulder dislocation? The shoulder joint is the most mobile joint in the body and allows the arm to move in many directions. This ability to move makes the joint inherently unstable and also makes the shoulder the most often dislocated joint in the body. In the shoulder joint, the head of the humerus (upper arm bone) sits in the glenoid fossa, an extension of the scapula, or shoulder blade. Because the glenoid fossa (fossa = shallow depression) is so shallow, other structures within and surrounding the shoulder joint are needed to maintain its stability. Within the joint, the labrum (a fibrous ring of cartilage) extends from the glenoid fossa and provides a deeper receptacle for the humeral head. The capsule tissue that surrounds the joint also helps maintain stability. The rotator cuff muscles and the tendons that move the shoulder provide a significant amount of protection for the shoulder joint.

Dislocations of the shoulder occur when the head of the humerus is forcibly removed from its socket in the glenoid fossa. It's possible to dislocate the shoulder in many different directions, and a dislocated shoulder is described by the location where the humeral head ends up after it has been dislocated. Ninety percent or more of shoulder dislocations are anterior dislocations, meaning that the humeral head has been moved to a position in front of the joint. Posterior dislocations are those in which the humeral head has moved backward toward the shoulder blade. Other rare types of dislocations include luxatio erecta, an inferior dislocation below the joint, and intrathoracic, in which the humeral head gets stuck between the ribs.

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 gradual weakening of the ligaments and cartilage that supports the shoulder. Even in these cases, however, there still needs to be some force applied to the shoulder joint to make it dislocate.

Anterior dislocation 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 Dislocation 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 because X-rays may not easily show a posterior dislocation, the diagnosis is often missed should the patient present for evaluation of shoulder painshoulder pain

Other types of dislocation subluxation is defined as a partial or incomplete dislocation that usually stems from changes in the mechanical integrity of the joint Fracture are broken bones. Fractures commonly involve the clavicle (collar bone), proximal humerus (top of the upper arm bone), and scapula (shoulder blade

A.Subluxation B.Partial dislocation C.Complete dislocation Subluxation (A) Partial dislocation (B) Complete dislocation ©

Treatment Physical Therapy In the acute phase of a dislocated shoulder, therapy should be limited. The arm should be immobilized in a sling and swathed for 1-3 weeks Surgical Intervention The recurrence rate for shoulder instability is highly dependent on the age of the patient. Nonoperative care should be performed first before entertaining the thought of surgery