The shoulder joint complex consists of 4 separate joints which act in a highly coordinated fashion and can be considered the ‘core’ of the upper limb. Functionally it is useful to think of the upper limb as a crane. The scapula (shoulder blade) can be considered the ‘base’ and for the upper limb to function effectively, this needs to be held firmly onto the body by muscles collectively known as the ‘scapula stabilisers’, which attach to both the neck and the spine. The upper limb (‘the arm of the crane’) connects to the scapula via a ball and socket joint (glenohumeral joint). Unlike the hip joint which has a deep socket, the glenohumeral joint has a relatively shallow socket and is therefore inherently unstable. However this design affords us mobility providing us with diverse movements such as reaching overhead and scratching our back. Stability of this joint is provided by a group of small muscles called the rotator cuff that work constantly to ‘pull’ the ball into the socket wherever our arm is in space thus preventing dislocation. Normal function of these muscles is dependent on normal function of the scapula stabiliser muscles.