Definition
By Gregory R. Waryasz, MD
The subacromial bursa of the musculoskeletal system is characterized by its location.
It is part of the glenohumeral joint. It consists of a synovial fluid surrounded by a synovial membrane.
Its unique structural feature is that it is located acromion, coracoacromial ligament and deltoid superiorly and the supraspinatus tendon and joint capsule inferiorly. Normally this bursa does not communicate with the glenohumeral joint cavity.
The subacromial bursa as well as all other bones, muscles, and ligaments of the body are derived of mesodermal origin in the embryo.
The function of the bursa is to provide a cushion between bones, tendons, and muscles. This helps to reduce friction and allow free movement of structures. This bursa specifically helps the movement of the supraspinatus tendon under the coracoacromial arch and also the deltoid over the humerus and joint capsule.
Common diseases include bursitis. Bursitis is inflammation of the bursa.
Commonly used diagnostic procedures include clinical history, physical exam, and MRI.
It is usually treated with physical therapy and NSAIDs. Some patients require steroid injections.
References
Elstrom J, Virkus W, Pankovich (eds), Handbook of Fractures (3rd edition), McGraw Hill, New York, NY, 2006.
Koval K, Zuckerman J (eds), Handbook of Fractures (3rd edition), Lippincott Williams & Wilkins, Philadelphia, PA, 2006.
Lieberman J (ed), AAOS Comprehensive Orthopaedic Review, American Academy of Orthopaedic Surgeons, 2008.
Moore K, Dalley A (eds), Clinically Oriented Anatomy (5th edition), Lippincott Williams & Wilkins, Philadelphia, PA, 2006.