Chronic subacromial bursitis
The subacromial bursa sits like a flattened balloon containing fluid under the hard cap of bone at the shoulder where it acts to lubricate shoulder movement and to protect the tendons lying underneath. It can be involved in impingement syndrome and is a relatively common cause of lingering pain at the shoulder. It has a close relationship with the rotator cuff tendons and the shoulder joint itself and problems may coexist. Prolonged inflammation within the bursa can cause scarring between its layers and may lead to a frozen shoulder.
Patients usually complain of a dull ache in the deltoid muscle overlying the top of the arm and it may be painful to lie on that side at night. The condition produces a ‘muddle’ of signs, with several movements causing pain, and lifting the arm sideways away from the body to shoulder height may pinch the bursa causing pain.
Physiotherapy can help and the bursa can respond well to treatment with mobilisations and stretching techniques, with exercises and advice on posture to prevent the problem recurring. It can also be treated with an anti-inflammatory injection, usually steroid, after which patients should avoid the aggravating activity for up to two weeks to allow the bursitis to settle.