The association between body fat and rotator cuff tear: The influence on rotator cuff tear sizes

Background Rotator cuff tear (RCT) has a multifactorial etiology. We hypothesized that obesity may increase the risk of RCT and influence tear size. Materials and methods A case-control design study was used. We studied 381 consecutive patients (180 men, 201 women; mean age ± standard deviation, 65.5 ± 8.52 years; range, 43-78 years) who underwent arthroscopic rotator cuff repair. Tear size was determined intraoperatively. The control group included 220 subjects (103 men, 117 women; mean age ± standard deviation, 65.16 ± 7.24 years; range, 42-77 years) with no RCT. Body weight, height, and bicipital, tricipital, subscapularis, and suprailiac skinfolds of all participants were measured to obtain body mass index (BMI) and the percentage of body fat (%BF). For the purposes of the study, the 601 participants were divided into 2 groups by BMI (group A, BMI ≥ 25; group B, BMI Results The highest ORs for both men (OR, 2.49; 95% confidence interval, 1.41-3.90; P  = .0037) and women (OR, 2.31; 95% confidence interval, 1.38-3.62; P  = .0071) were for individuals with a BMI ≥30; 69% (N = 303) of group A and 48% (N = 78) of group B had RCTs. Patients with RCT had a BMI higher than that of subjects with no RCT in both groups ( P  = .031, group A; P  = .02, group B). BMI and %BF significantly increased from patients with a small tear (BMI, 27.85; %BF, 37.63) to those with a massive RCT (BMI, 29.93; %BF, 39.43). Significant differences were found ( P  = .004; P  = .031). Conclusions Our results provide evidence that obesity, measured through BMI and %BF, is a significant risk factor for the occurrence and severity of RCT.