Fibrosis in the subacromial bursa and outcome after acromioplasty

The subacromial bursa tends to undergo proliferative or degenerative changes in patients with impingement syndrome. The aim of the study was to quantify the degree of fibrosis in the subacromial bursa in context with the outcome after acromioplasty.

Twenty-one patients with impingement syndrome underwent acromioplasty, and in each case biopsies from the subacromial bursa were taken. Fibrosis in the subacromial bursa was assessed histologically with van Gieson staining technique, and a three-graded scale was used. Five normal shoulders from an autopsy series served as controls.

Ten patients had severe fibrosis, eight had moderate fibrosis and one patient had no fibrosis at all. All normal controls had no fibrosis. The postoperative outcome seemed to be more favourable in patients with severe fibrosis (7 out of 10) contrary to patients with moderate fibrosis of whom only three out of eight were graded as a success. The outcome of acromioplasty in patients with impingement was clearly dependent on the degree of fibrosis in the subacromial bursa.