Shoulder dislocation or dislocation


What is a shoulder dislocation?

Normally, a shoulder dislocation or dislocation tends to force the arm into the front and lower part of the shoulder, which is favored by the anatomical shape of the joint.

The bones of the shoulder are the scapula and the ball at the top of the humerus (head of the humerus). The cavity of the scapula is shallow and not particularly pronounced, but it is enlarged and deepened by the acetabular lip or cartilage framing.

The joint is supported on all sides by the ligaments and joint capsule , and then covered by the rotator cuff muscles. The rotator cuff, also known as the muscle-tendon cap, is made up of four muscle tendons that originate at the shoulder blade and end at the top of the humerus. They strengthen the shoulder joint at the top, front, and back, but the weak point of the rotator cuff is at the front and bottom.

A subluxation is a partial dislocation of the arm. It describes an incomplete loss of contact between the two joint surfaces. If the subluxation is 50%, the articular surfaces have lost half of their normal contact and the joint is partially dislocated. A dislocation corresponds to a hundred percent subluxation.

Causes of shoulder dislocation

No joint is affected more often by a dislocation than the shoulder joint. The movement of the arm is not guided and blocked by other bones, so the shoulder is extremely mobile, but also more unstable than the other joints.

All or part of the arm may “exit” the socket forward, backward, or down. In addition, the ligaments connecting the shoulder bones can become overstretched or torn, a complication of the dislocation.

A strong blow to the shoulder, as in sudden trauma, causes the arm to come out of its seat (dislocation). Excessive rotation can dislocate the head of the humerus from the socket of the scapula.

An incomplete dislocation or partial dislocation occurs when the humerus remains only partially attached to the shoulder.

The following causes can lead to a dislocated shoulder:

  • Sports accidents: this injury is common in contact sports, such as soccer and hockey, and sports with a high risk of falling, such as skiing, gymnastics, and volleyball.
  • Trauma isn’t unique to sports: the impact of a car accident on the shoulder is a common cause of shoulder dislocation.
  • Falls: the shoulder may dislocate when falling on the stairs or when stumbling.

Risk factors of shoulder dislocation

Several factors play an important role in the occurrence of a shoulder dislocation. The following people are at higher risk:

  • Men: They are more likely to have shoulder dislocations than women.
  • Between the ages of 20 and 30. People of this age are mostly active in sports, which increases the risk of injury.

Signs and symptoms of shoulder dislocation

  • A visibly deformed or dislocated shoulder;
  • Swelling;
  • bruising (hematoma);
  • intense shoulder pain ;
  • inability to move the arm;
  • the dislocated shoulder can cause numbness, weakness and tingling in the affected area, but also in the neck and down the arm;
  • the muscles of the shoulder can spasm from the trauma, often increasing the intensity of the pain.

When should a doctor be consulted? It can be difficult to distinguish a humerus fracture from a dislocation.
If your child’s shoulder appears dislocated, an emergency room should be sought immediately.

In anticipation of the doctor:

The joint must not be moved, so it should be kept still in the current position with towels or splints. Do not attempt to move or set the shoulder as this could damage the joint and surrounding muscles, ligaments, nerves and blood vessels.
Cool the injured joint with ice compresses. The cold helps reduce pain and swelling, and slows down internal bleeding and fluid buildup in and around the shoulder joint.

Complications of shoulder dislocation

The complications of a shoulder dislocation are:

  • Tear of the muscles, ligaments and tendons that strengthen the shoulder joint.
  • Injuries to the nerves or blood vessels inside and outside the shoulder joint.
  • Vulnerability to re-injury (shoulder instability) with severe or repeated dislocation.
  • If the ligaments or tendons in the shoulder are stretched or torn, or if the nerves or blood vessels in the shoulder area have been injured, surgery may be necessary to repair these tissues.

Investigations and tests

After the anamnesis interview (about when and how the injury occurred, whether there are any serious health problems or other injuries), the doctor will conduct a short general visit and then examine the affected shoulder closely.
The deltoid or deltoid (round muscle covering the shoulder joint) appears flattened on the affected side.
Any movement of the arm causes pain in the shoulder.
Pulse rate, sensitivity, and hand movements are usually unaffected.

Nerves, blood vessels, ligaments, tendons and muscles can also be injured. This damage can be difficult to diagnose because the patient is unable to move due to the dislocated shoulder.

An X-ray is one of the most useful imaging procedures when diagnosing a shoulder dislocation. It shows the loss of contact of the articular surfaces and other lesions such as the fracture of the humerus or a tear in the ligaments that connect the collarbone and shoulder blade.

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