Shoulder dislocation (shoulder luxation)

Shoulder dislocation is characterized by a dislocation of the humeral head from the glenoid cavity. There are basically two forms of this dislocation:

When the shoulder is dislocated due to an accident or injury, it is called a traumatic shoulder dislocation. However, a shoulder dislocation can also occur without any harmful effects, simply from movements of the shoulder joint, which is called a habitual shoulder dislocation.

Both habitual and traumatic shoulder dislocation can develop in a variety of ways, but often deformities of the shoulder joint are involved in the development of a dislocation. In most cases, the head of the humerus is displaced forward or downward after it has popped out of the socket. Only rarely is the head of the humerus displaced posteriorly.

Many people suffer a shoulder dislocation in the course of their lives, as the shoulder joint is often subjected to a lot of stress due to its high mobility. As a ball and socket joint, the shoulder joint is one of the most mobile joints in the human body. However, the glenoid cavity is quite small compared to the head of the humerus, which is why the contact surface between the head and the glenoid cavity is also very small. Although this gives the joint its great freedom of movement, it makes it unstable. In addition, the muscles of the shoulder are not very tight, which is why the head of the humerus can jump out of the socket more easily.

The traumatic form of shoulder dislocation occurs in very many cases due to lever movements of the upper arm, as well as during rotations of the upper arm away from the body. Accidents during sports activities, cycling or car accidents are also often responsible for traumatic shoulder dislocations. Only in a few cases does shoulder dislocation occur when the arm is extended.

Habitual shoulder dislocation usually has a genetic background. Anatomical changes of the glenoid cavity and the humeral head often lead to shoulder dislocations. Furthermore, weakly developed connective and muscular tissue around the shoulder joint can promote the development of a dislocation.

A shoulder dislocation is usually easy to recognize because it is very painful and is typically accompanied by limited motion and an altered position of the shoulder joint. In addition, the head of the humerus, as well as the empty glenoid cavity, can be easily palpated. After some time, a swelling in the shoulder joint is usually palpable or visible.

After a dislocation of the shoulder, immediate cooling and immobilization of the shoulder joint are very important.

In contrast to traumatic shoulder dislocation, the habitual form is usually not as painful and can in most cases be reset by the affected person himself.

A shoulder dislocation can usually be diagnosed by the typical symptoms in combination with an X-ray examination and a test of the shoulder mobility (drawer test). Usually an X-ray is taken from the front as well as from the side to get a better view of the joint. In this way, it is also possible to determine the exact position of the humeral head.

Especially in the diagnosis of habitual shoulder dislocations, an ultrasound examination can be very helpful because it allows the muscles, as well as muscle tendons and ligaments, to be well visualized. In the case of complex dislocations, additional imaging techniques, such as a computed tomography scan and a magnetic resonance imaging scan, can be helpful in the diagnosis. In the case of habitual shoulder dislocation, a reflection of the shoulder joint (arthroscopy) may also be necessary.

A shoulder dislocation is treated by setting the dislocated upper arm, also called reduction. In many cases, this procedure is performed under anaesthesia. The reduction can be performed in various ways, basically pulling on the upper arm and then rotating the shoulder joint outwards. This combination of movements usually allows the head of the humerus to be reset into the socket. After the shoulder has been reset, it should be fixed in place using special bandages (such as the Gilchrist bandage). In addition, pain-relieving medications, such as Novalgin® and Voltaren®, can be taken.

Habitual shoulder dislocation can usually be reduced without any problems; in most cases, the shoulder can be returned to its correct anatomical position with a simple movement.

After the shoulder has been immobilized for several weeks, the shoulder muscles should be exercised and built up with specific physical therapy.

In some cases, it is not possible to immobilize a traumatic shoulder dislocation using the various reduction techniques. In this case, or if the shoulder joint is not sufficiently stable even after reduction, surgical intervention is necessary. Habitual shoulder dislocation only needs to be treated by surgery in a few cases. In any case, it is necessary to ensure that other damage to the shoulder, such as an injury to the humerus, glenoid cavity or shoulder girdle, is adequately treated. In some cases, this can be done by means of a reflection of the shoulder joint, an arthroscopy.

Patients who suffer a shoulder dislocation for the first time and have no other shoulder injuries have a very good prognosis in most cases. The risk of further shoulder dislocation is increased, especially in young and athletic patients.

In the habitual form, shoulder dislocations occur regularly, but can be prevented in some patients by surgical intervention.

However, if other structures of the joint, such as the articular cartilage, the capsule or the bone itself, are damaged in the shoulder dislocation, the prognosis is worse.

Through proper muscle training, you can strengthen the shoulder joint and thus take precautions against shoulder dislocation. When doing sports, you should pay particular attention to the right equipment and not put too much strain on the shoulder.