Figure 22. Heterogeneity of the normal rotator cuff. Coronal (longitudinal) US image of a 16-year-old patient with a history of shoulder instability shows multiple hypoechoic zones (arrows) extending to the fibrocartilaginous insertion site. The cuff was normal at arthroscopy. Heterogeneity of the normal rotator cuff is attributable to complex interdigitation of intra- and intertendinous contributions.