A bursa is a potential space that sits between anatomic structures to allow for smooth gliding. The subacromial-subdeltoid bursa (shoulder bursa) overlies the rotator cuff tendons and sits underneath the acromion, the outermost boney prominence of the shoulder blade along the lateral shoulder. Should bursitis implies acute inflammation of the bursa, however sometimes there can be bursal thickening, representing more chronic shoulder pathology. In both cases, pain can result.
The subdeltoid bursa is simply the part of the shoulder bursa that extends beyond the acromion. The subacromial bursa, the subdeltoid bursa, the subacromial-subdeltoid bursa (SASD), or simply the shoulder bursa are most often used interchangably.
The subacromial bursa is simply the part of the shoulder bursa that sits underneath the acromion. The subacromial bursa, the subdeltoid bursa, the subacromial-subdeltoid bursa (SASD), or simply the shoulder bursa are most often used interchangably.
The subacromial-subdeltoid bursa can fill or become irritated secondary to rotator cuff injury, as with a full thickness tear the glenohumeral (shoulder joint) which normally houses synovial (lubricating) fluid will now communicate with the bursa. The bursa can also become irritated if there is a calcific deposit within the rotator cuff tendon which happens from overuse. The bursa can become repetitively irritated by the “impingment” that occurs as a calcium deposit may cause catching of the rotator cuff tendon as it slides underneath the acromion when raising your arm. Impingement can result from instability of the shoulder ligaments or poor muscular control as well. These factors can increase irritation of the bursa. Certain systemic disorders (such as inflammatory arthritis) can predispose to bursitis. Infection can cause acute bursitis as well.
Pain from shoulder bursitis typically overlaps with rotator cuff pain. Rotator cuff pain commonly causes tenderness in the front of the shoulder. You may have pain and stiffness when you lift your arm. There may also be pain when the arm is lowered from an elevated position. Frequently there is pain at night lying on the affected side. If bursitis is representative of a rotator cuff tear, there may be weakness as well.
Cortisone injections typically work very well to relieve pain from bursitis. The duration of relief is highly variable but may allow for a patient to more comfortably complete physical therapy and so the injection becomes more curative in that sense. Regenerative-type injections may be of benefit (such as PRP). If bursitis is caused by calcific tendinosis, then debridement or removal of the calcium deposit can help. This can be done with a needle under ultrasound (typically called an aspiration-lavage) or by a device such as Tenex which provides micro-debridement.