Fatty Infiltration & Atrophy of the Rotator Cuff Do Not Improve Following Rotator Cuff Repair
Authors: J Bishop et al.
References: Presented at AAOS 2004
Prospective study of pre- and post-operative MRI's demonstrate neither fatty infiltration or muscle atrophy appear to reverse following rotator cuff repair.
Introduction: There has been controversy as to whether rotator cuff repair (RCR) can improve the fatty infiltration (FI) and muscle atrophy (MA) often seen in large rotator cuff tears. This study compares FI and MA seen on pre- and post-operative MRIs as part of a prospective outcome study of rotator cuff repair.
Methods: The clinical outcome of 39 patients (mean 62yo, minimum follow-up 1yr) following RCR was determined with ASES and Constant scores. FI was graded on a 5 point scale and MA on a 4 point scale on pre and post-operative MRIs.
Results: Pain, function, ASES and Constant scores all significantly improved following RCR (p<0.05). FI and MA positively correlated with tear size (p<0.0001, r=0.712).
Those with greater degrees of supraspinatus FI were more likely to retear (p<0.001, r=0.745). ASES and Constant scores, and strength measurements, all inversely correlated with FI and MA (p<0.03). Strength in FF and ER was affected more by infraspinatus FI than similar levels of the supraspinatus. Pain relief was independent of the severity of FA/MA. Only one patient improved from moderate to mild MA. In 18 MA/FI were unchanged and in 21 MA and/or FI was actually worse.
Conclusion: FI and MA significantly affect the functional outcome following RCR even though pain is relieved. Neither FI nor MA appear to reverse following surgery, even with a successful outcome, and in moderate to severe cases may actually worsen. Patients’ expectations should not include reversal of muscle degeneration once present.