Arthroscopy 2002 Jan;18(1):16-20
The correlation between bursoscopic and histologic findings of the acromion undersurface in patients with subacromial impingement syndrome.
Suenaga N, Minami A, Fukuda K, Kaneda K.
of Orthopaedic Surgery, Hokkaido University School of Medicine, Sapporo,
PURPOSE: Ideally, decompression of the
coracoacromial arch in patients with shoulder impingement syndrome should be
done only at the site of impingement. However, it is very difficult to
determine the exact site of impingement before acromioplasty. The objectives
of this study were to investigate the relationship between findings and the
histopathologic changes of the undersurface of the acromion in subacromial
impingement syndrome and to evaluate the usefulness of bursoscopy in
identifying the site of the impingement. TYPE OF STUDY: Case series. METHODS:
We investigated the correlation between subacromial bursoscopic findings and
histopathologic changes of the coracoacromial arch in 50 patients with
subacromial impingement syndrome. The acromion and the coracoacromial
ligaments removed during acromioplasty were fixed in 10% formalin,
decalcified, embedded in paraffin, and cut into sections along the direction
of the coracoacromial ligament. After staining with toluidine blue, the
specimens were evaluated for pathology using an optical microscope. RESULTS:
The pathologic changes were classified into 3 types according to the direction
of proliferative fibrocartilaginous changes at the enthesis of the acromial
insertion of the coracoacromial ligament. The bursoscopic findings were
classified into 4 types. Subacromial abnormalities in the bursoscopy findings
correlated with histopathologic changes at the undersurface of the acromion.
On the other hand, cases with normal findings on the undersurface of the
acromion on bursoscopy had hypertrophic changes of fibrocartilage at the
insertion of the coracoacromial ligament to the acromion. These results
suggest that, with normal findings on the undersurface of the acromion in
patients with subacromial impingement syndrome, there is impingement at the
coracoacromial ligament. CONCLUSIONS: Bursoscopy is a useful procedure to
determine the impingement site in patients with subacromial impingement.