Shoulder impingement

1-What is impingement? 

 This refers to an overgrowth of bone on the under surface of the collar bone which subsequently can rub (impinge) against the underlying rotator cuff muscle. With repeated activities, this can cause a tear of the rotator cuff muscle.

2- How do you diagnose impingement?

 The diagnosis is made during clinical examination, confirmed with x ray. An ultrasound or MRI scan is also necessary to exclude a rotator cuff tear, which unfortunately is very common as presentation is often delayed.

An X ray of the left shoulder, seen from straight in front. The Sub-acromial space is seen between the top of the humerus and the Acromion above

Sub acromial spur

Frozen shoulder leading to narrowing of the sub acromial space with evidence of bone spur arising from inferior surface of the acromial process.