Shoulder Impingement and bursitis are common causes of pain and loss of shoulder function.
The tendon of the supraspinatus muscle runs from the shoulder blade onto the head of the humerus passing under a bony part of the shoulder blade known as the acromion.
Shoulder Impingement occurs when there is narrowing of the space that the tendon passes through. This can result in disruption of the normal movement of the tendon and lead to pain in the shoulder when using the arm overhead as well as pain at night with discomfort sleeping on the affected shoulder.
The narrowing can be caused by bony spurs on the undersurface of the acromion or by a hook-shaped acromion. Arthritis of the joint between the collar-bone and the acromion can also reduce the space available for the tendon. Over time these bony projections can cause a tear of the tendon.
To assist in the smooth gliding motion of the supraspinatus tendon a fluid filled sac known as a bursa occurs between the tendon and the acromion. This bursa can become inflamed and cause pain. This is known as subacromial bursitis.
Initial treatment for impingement and bursitis includes simple pain medication and physiotherapy. An injection of local anaesthetic and steroid solution into the subacromial space is useful to confirm the diagnosis of impingement and bursitis and can often provide lasting pain relief by treating the inflammation.
When impingement and bursitis fail to resolve after non-operative measures, surgical treatment using an arthroscopic (key-hole) procedure to remove any bony causes of impingement and to excise the inflamed bursa is highly successful.
Surgery is performed under a general anaesthetic with a nerve-block to reduce post-operative pain. Patients usually are in hospital overnight and return home the day after surgery. A shoulder sling is used for one to two weeks and a physiotherapy program is started to prevent stiffness and help regain shoulder function.