Preoperative degree of fatty degeneration in cuff muscles was negatively correlated with postoperative overall shoulder functioning after the arthroscopic rotator cuff repair.
There have been several reports on the correlation of fatty degeneration of rotator cuff muscles with functional outcomes after open rotator cuff repair. The purpose of this study was to determine whether the fatty degeneration in cuff muscles predicts functional outcomes after arthroscopic rotator cuff repairs.
From February 2003 to March 2004, fifty-one shoulders were treated by arthroscopic rotator cuff repair. Of these, forty-nine shoulders were followed up. Mean age at surgery was 59 years. Mean follow-up time period was 26 months (24 – 39 months). There were 4 partial thickness tears, 15 small tears, 19 medium tears, 7 large tears, and 6 massive tears. Preoperative degree of fatty degeneration was determined by the Global Fatty Degeneration Index (GFDI), developed by Goutallier. The isometric strength of shoulder flexion was quantified utilizing a hand-held dynamometer. Outcome assessment was evaluated using the Japanese Orthopaedic Association Shoulder Scoring system (JOA score: 100 total points).
The mean JOA score was significantly improved from 63 preoperatively to 94 postoperatively (p<0.001). GFDI was positively correlated with the size of the tear (p<0.01). Postoperative JOA score and isometric flexion strength were negatively correlated with GFDI (p<0.01). If the fatty degeneration index in supraspinatus muscle was smaller than or equal to one, then the mean isometric flexion strength at follow-up was ninety percent of the unaffected side.
Preoperative degree of fatty degeneration in cuff muscles was negatively correlated with postoperative overall shoulder functioning after the arthroscopic rotator cuff repair. GFDI was found to be a very useful index to predict functional results after the arthroscopic rotator cuff repairs.
© 2007 Arthroscopy Association of North America. Published by Elsevier Inc. All rights reserved.