Ultrasound dimensions of the rotator cuff in young healthy adults

BackgroundNo studies have looked at the rotator cuff dimensions in the young healthy population using ultrasonography. Our aim is to define the ultrasound dimensions of the rotator cuff in the healthy young adult population and explore correlations with other patient characteristics.MethodsThirty male and 30 female healthy volunteers (aged 18-40 years), with no shoulder problems, underwent ultrasound assessment of both shoulders by a musculoskeletal radiologist. The dimensions of the rotator cuff, deltoid, and biceps were measured in a standardized manner.ResultsA total of 120 shoulders were scanned. The mean maximum width of the supraspinatus footprint was 14.9 mm in men and 13.5 mm in women (P < .001). The mean thickness of the supraspinatus tendon was 4.9 mm in women and 5.6 mm in men. The mean thickness of the subscapularis was 4.4 in men and 3.8 mm in women and for the infraspinatus was 4.9 mm in men and 4.4 mm in women. There was no correlation between height, weight, biceps, or deltoid thickness with any tendon measurements. Apart from supraspinatus tendon thickness, the difference between dominant and nondominant shoulders in the same sex was not significant for any other tendon dimensions.ConclusionThis study has defined the dimensions of the rotator cuff in the young healthy adult, which has not been previously published. This is important for the documentation of normal ultrasound anatomy of the rotator cuff and also demonstrates that the asymptomatic contralateral shoulder can and should be used to estimate the expected dimensions.