[Purpose]The purpose of this study is to determine the diagnostic performance of MR arthrography and MR bursography in evaluating an incomplete rotator cuff tear.
[Materials and Methods]Twenty shoulders in 19 cases of surgically proved incomplete rotator cuff tears (8 articular side,9 bursal side,3 intratendinous alone ) were studied retrospectively. Fourteen patients were men and 5 patients were women. Their age range was 29-80 years (average age,42.5 years).
Six of the 8 shoulders with an articular side tear and 6 of the 9 shoulders with a bursal sid e tear were accompanied by intratendinous tears. After a 10m1 injection of diluted Gd-DPTA into the articular capsule or subacromial bursa, Ti weighted (SE) MR images were obtained on the 1.5T MR system. The injection site was determined by the tear site expected by the arthrogram previously performed. An incomplete tear was diagnosed using MR arthrograms and MR bursograms whenever a sharply delineated region in the cuff revealed an increased signal intensity without encompassing the whole thickness of the cuff substance.
[Results]MR arthrography and MR bursography reveale dadequate diagnosis in 8 pf the 8 (100%)articular side tears, in 5 of the 9 (55.5%) bursal side tears and in 1 of the 3 (33.3%) intratendinous tears. Combined intratendinous tears were identified in 6 of the 6(100%) articular side tears, and in 3of the 6 (50%) bursal side tears. In all of the 4 cases which had failed to interpret bursal side tears, Gd-DPTA had not been injected into the subacromial bursa accurately.
[Conclusion]Our preliminary results show that MR arthrography is a reliable method for demonstrating articular side tears and the intratendinous tears accompanied by them. MR bursography is not helpful because it is difficult to inject Gd-DPTA accurately into the subacromial bursa.
