A bursa is a fluid-filled sac found at several locations in the human body. It serves to lubricate joints and body surfaces exposed to higher degrees of wear and friction. The subacromial space in the shoulder is such a location. The subacromial bursa is bordered superiorly by the acromion, coracoid, coracoacromial (CA) ligament and the proximal deltoid muscle fibers and inferiorly by the fibers of the supraspinatus muscle. The height of the subacromial space ranges from approximately 1.0 to 1.5 cm. Inflammation of the bursa can occur due to a variety of reasons leading to the development of subacromial bursitis.
Faruqi T, Rizvi TJ. Subacromial bursitis. 2022 Jun 27. In: StatPearls [Internet]. Treasure Island (FL): StatPearls Publishing; 2022 Jan–. PMID: 31082140.