Shoulder instability

The shoulder is one of the most commonly dislocated joints.

Shoulder instability means that the shoulder can dislocate (be pulled out of joint) or sublux (moves more than it should do) during day-to-day activities. Both dislocation and subluxation can happen for a variety of reasons. How it happens affects the type of treatment you will receive.

The three main causes of shoulder instability are:

  • Traumatic dislocation – where the shoulder undergoes an injury with enough force to pull the shoulder out of joint (eg. a violent tackle in rugby, or a fall onto an outstretched hand)
  • Non-traumatic dislocation –caused by repeated shoulder movements gradually stretching out the soft tissue cover around the joint causing the rotator cuff muscles to become weak
  • Positional non-traumatic – the ability to dislocate your shoulder without any form of trauma. This may start off as a party trick, but if repeated, it can happen during everyday activities

For more information on shoulder instability download the patient information leaflet on the right.