MR imaging of rotator cuff tears: Is there a diagnostic benefit of shoulder exercise prior to imaging

The purpose of this study was to determine if shoulder exercise prior to MR imaging accentuates findings related to rotator cuff tears. In 32 consecut ive patients undergoing MR imaging to evaluate the rotator cuff, after rout ine MR examination, the joint was moved by active or passive exercise (circ umduction, including abduction, if possible) in an attempt to redistribute any joint fluid. The exercise was performed according to pain tolerance and for no longer than 4 minutes. The coronal oblique fast spin-echo T2-weight ed images of these patients performed before exercise were reviewed by cons ensus agreement of two musculoskeletal radiologists who were blinded to cli nical information. The appearance of the rotator cuff tendons and the distr ibution of fluid in the glenohumeral joint bt ere determined. The identical postexercise MR images then were placed alongside the corresponding preexe rise MR images, and a direct comparison of findings was made with regard to any change in the appearance of the rotator cuff or joint fluid by consens us opinion of the same two radiologists. Five patients (five shoulders) cou ld not perform exercise because of pain. In the remaining 27 patients (27 s houlders), changes in the location of joint fluid were seen when the preexe rcise and postexercise images were reviewed together, the diagnosis of part ial rotator cuff tear (n = 8) was changed to normal in five cases, and the diagnosis of partial tear was made with more confidence in one case. The di agnoses of normal rotator cuff (n = 16) and complete rotator cuff tear (n = 3) were unchanged. Eight patients had arthroscopy; in each of these, the p reexercise and postexercise images showed similar results, and proved to be correct surgically (six normal, one partial rotator cuff tear, and one com plete rotator cuff tear). Although postexercise MR images show changes in t he distribution of joint fluid when compared to preexerice images, the diag nostic benefits of the postexercise images in the analysis oft he rotator c uff appear to be limited. (C) Elsevier Science Inc., 1999.