抄録
Previously, we reported that high MRI signal intensity at the rotator cuff insertion was seen after rotator cuff repair in 29% of all cases examined. At this time, we reported the background and characteristics of cases with simultaneous high and low signal changes. We investigated 71 shoulders of 70 patients showing high intensity signal changes of the rotator cuff on MRI 6 months after rotator cuff repair. We classified the patients into 2 groups: the 1st consisted of 37 shoulders (L group) with simultaneous low signal intensity changes of the rotator cuff, and the 2nd group consisted of 34 shoulders (H group) with no low signal intensity changes. We examined the patients' JOA score, UCLA score, range of motion (ROM) of the shoulder, and reviewed comparisons between both groups. In addition, we examined the rotator cuff tear size at the time the of operation. Based on the clinical evaluations, the UCLA and JOA scoresshowed no statistical differences between both groups at pre-operation, 6 months and 1 year postoperatively. The H group was larger than the L group in average rotator cuff tear size. The improvement rate of range of motion of abduction and external rotation of the L group was statistically larger than the H group. Factors correlating to no low signal changes in rotator cuff insertions showing high signal changes 6 months postoperatively are large tear size and poor improvement of range of motion of abduction and external rotation.
