''Bursal reactions'' in rotator cuff tearing, the impingement syndrome, and calcifying tendinitis

Subacromial bursal specimens from 63 patients undergoing surgery for rotator cuff tearing (n = 43), the impingement syndrome (n = 14), and calcifying tendinitis (n = 6) were studied to characterize the reactions that develop at the tendinopathy ''lesional'' sites. Intensity of the bursal reactions and production of type III collagen vary considerably, with the highest incidence of both seen in patients with rotator cuff tears. The intensity of bursal reactions correlated with the degree of formation of perivascular new collagen and type III collagen expression. In 22 of the 63 patients the bursal reaction distant to the tendon lesion was also studied. It was minimal and did not correlate to the lesional bursal findings. A strong correlation, however, existed between surgical appearance and histologic grading. The term ''localized bursal reaction'' as opposed to bursitis more correctly describes bursal involvement. Resection of bursal tissues should be limited to the lesional tissue that interferes with subacromial motion.