Muscle fatty infiltration in rotator cuff tears: Descriptive analysis of 1688 cases

SummaryIntroductionFatty infiltration (FI) is an important prognosis factor in the anatomical and functional outcomes of rotator cuff repairs. The objective of this study was to analyze the natural history of muscle FI and better evaluate its onset and aggravation time frame.Material and methodsA total of 1688 medical charts of patients operated on for rotator cuff tear and whit a preoperative CT arthrogram (82%) or an MRI (18%) were reviewed. Surgery was performed between 1988 and 2005. The FI of each muscle was assessed as minimal (in Goutallier's stages 0 and 1), intermediate (in stage 2), and severe (in stages 3 and 4). Regarding supraspinatus, we retained the mean FI observed in the sagittal, coronal, and axial planes; for the infraspinatus and the subscapularis, we retained the observed mean on two views at the upper and lower levels of the glenoid in the axial plane.ResultsWe found a statistically significant correlation (p<0.0005) between FI, the type of tendon lesion, and patient age for the supraspinatus, the infraspinatus, and the subscapularis. Statistically, the FI significantly increased (p