The shoulder joint is a ball and socket joint, similar to the hip; however, the socket of the shoulder joint is extremely shallow, and thus inherently unstable.
This means that the bones of the shoulder are not
held in place adequately, and therefore extra support is needed.
To compensate for the shallow socket, the shoulder joint has a rim of cartilage called a labrum that forms a cup for the end of the arm bone (humerus) to move within by artificially making the shallow joint seem deeper.
This cuff of cartilage makes the shoulder joint much more stable, and allows for a very wide range of movements.
The labrum is made of a thick tissue that is susceptible to injury with trauma to the shoulder joint.
Often a labral tear can happen alongside a traumatic dislocation of the shoulder.
The labrum also becomes more brittle with age, and can fray and tear as part of the ageing process.
Symptoms of a labral tear depend on where the tear is located, but may include:
In addition, some types of labral tears, can increase the potential for shoulder dislocations.