What is it?

Shoulder instability is a term used to describe a weakness in the structures of the shoulder that keep the joint stable, often leading to frequent dislocations. As one of the most flexible joints in the body, the shoulder maintains stability through a balance of support between the dynamic structures (muscles and tendons) and static structures (ligaments and joint shape).

Shoulder instability typically occurs in one of two directions, anterior (forward) or posterior (backwards), anterior instability or dislocations are far more common than posterior. 

What are the symptoms?

The most noticeable symptom of shoulder instability is dislocation or subluxation of the joint. This is often accompanied by pain, clicking sensations, a feeling of instability and in some cases, weakness, tingling, and pins and needles in the arm. Many patients report a feeling of apprehension or instability, as if ‘something is not quite right’. Posterior instability can also cause reduced range of movement and might mimic other common shoulder conditions, which need to be ruled out first. 

How does it happen?

Shoulder instability is also classified as traumatic, occurring after an injury or atraumatic, where the shoulder is exceptionally flexible and prone to dislocations from everyday forces. Instability can also occur from chronic overuse where the shoulder joint is damaged slowly over time.

Traumatic shoulder instability is the most common form. Often the joint is dislocated by a strong force and damaged, leaving it more unstable and vulnerable to future dislocations. Rugby and football players are commonly affected. However, dislocations can occur in the general public from something as simple as falling onto an outstretched hand.

How can physiotherapy help?

Shoulder instability is a complex condition, and each person will have a different combination of causes and structural deficiencies. Physiotherapists are trained to identify issues of coordination, control and strength that may be contributing to instability and provide an extensive rehabilitation program. For some patients, surgery is recommended to help restore some static stability to the joint. However, this is not the best pathway for everyone. If surgery is indicated, a full rehabilitation program is also recommended for the best outcomes. 

Helping patients to understand and manage their condition is an essential part of recovery. Physiotherapy is usually always recommended as the first line of treatment before surgery and can have excellent outcomes, with or without going under the knife. 

None of the information in this article is a replacement for proper medical advice. Always see a medical professional for advice on your injury.