Shoulder instability

Shoulder instability means that the shoulder joint is insufficiently stabilized. The humerus can therefore move too much in the joint. In some cases, this can actually cause the humerus to slip out of the joint head (luxation).

If an existing shoulder instability remains untreated, arthrosis in the shoulder joint may develop later on. Shoulder instability usually occurs as a result of an injury or trauma to the shoulder joint. The shoulder consists of 3 bones, the scapula, the humerus and the collarbone. 4 large muscles connect the scapula and humerus, and also ensure that the humerus remains firmly in the joint. The joint capsule itself consists of ligaments and loose tissue, which allows the shoulder joint unlimited freedom of movement.

Symptoms

One of the symptoms of shoulder instability is that the shoulder can easily be dislocated, i.e. it slips out of the joint head. Many patients describe their shoulder as feeling too loose, especially when the hand is raised above the head. Pain is a symptom when the shoulder only half slips out of the joint due to certain movements, i.e. it simply moves too much.

Avoiding these movements often leads to the development of incorrect posture, which then causes further secondary symptoms. If the shoulder becomes so unstable that it slips out of the joint head even with simple movements, this can be extremely painful for the person affected and can cause serious damage to the nerves around the shoulder joint. The article Physiotherapy after a shoulder dislocation might be of interest to you in this regard.

Causes

The causes of shoulder instability are almost always due to previous injuries. As already mentioned at the beginning, the ligaments and tendons in the shoulder joint are primarily responsible for ensuring that movements can be controlled and fluid and that the humerus is held stable in the joint head. If these ligaments and tendons are overstretched or even tear as a result of an accident or too rapid movement, this can lead to permanent shoulder instability.

Although the shoulder seems to be fine again after the acute injury has healed and there is no obvious damage, the ligaments and tendons may be too mobile due to the strain, much like a worn rubber band. This allows too much freedom of movement for the humerus in the joint, resulting in the typical feeling of looseness and, in the worst case, a dislocated shoulder. In rare cases, non-traumatic causes may also be present, for example, if the affected person has genetically weak ligaments that can make the shoulder joint unstable even through everyday work. The differentiation plays an important role in the choice of the treatment method, so it is important to discuss the exact history of the disease with your doctor if there are problems.