So-Called Calcifying Subacromial Bursitis

Abstract

Codman, in 1906, was the first to describe the symptom-complex which he designated as “subacromial bursitis.” He had not found any calcareous deposits in the cases he then reported. The following year Painter and Baer both reported cases of calcareous deposits and, in the light of present-day knowledge, they were probably both in error in stating that the deposits were situated in the wall of the bursa. They each reported having excised the entire subdeltoid bursa in four cases. Unfortunately many writers have wrongly followed their lead and described the deposits as occurring in the wall of the subacromial bursa and advised total excision of the bursa. Codman was the first to point out that the deposit is located beneath the bursa, in or on the supraspinatus tendon. It is most important for surgeons to realize that the deposit is not in the bursa but beneath its floor, in, on, or even under the supraspinatus tendon, otherwise they are likely to miss it at operation as did Painter in two of his four early operations, in which he reported excision of the subdeltoid bursa, and as did Stern, who probably limited his search to the interior of the bursa. Some confusion has arisen in the literature because various authors use the terms “subacromial bursa” and “subdeltoid bursa” as synonymous and interchangeable, whereas others regard them as separate entities. Experience has shown that there is only the one bursa and the general trend of opinion is to call it “subacromial.” The subacromial bursa is nearly as large as the palm of the hand of the individual in whom it is located, and, except for a small projection beneath the deltoid muscle, lies between the acromion process and the head of the humerus, where it is inaccessible for the complete excision so commonly and wrongly advised by numerous writers. In many of the cases with typical acute or chronic symptoms that are studied carefully at operation, the opened subacromial bursa is found to be entirely free from any pathologic changes, and the deposit is found in or even under the supraspinatus tendon. It, therefore, seems obvious that the symptoms must be caused by the tendon lesion and that the term “bursitis” is really a misnomer. Often a localized or rarely a diffused bursitis may co-exist and is probably induced by the adjacent tendon lesion, but the symptoms in no way differ from the cases in which the tendon alone is affected. Codman believes the deposits are due primarily to acute traumatic rupture of a few fibers of the supraspinatus tendon, with the occurrence at the site of rupture of a hematoma in which calcium salts are deposited.