Pathoanatomy of Rotator Cuff Tears

The rotator cuff and associated bony and soft tissue structures are complex, and rotator cuff tears present in a wide array of morphology and sizes. Shoulder arthroscopy has greatly expanded our knowledge about the pathoanatomy of cuff tears and associated lesions. Knowledge and recognition of common patterns of rotator cuff tears and associated lesions allow the shoulder surgeon to make rational decisions about the treatment of these lesions. Full-thickness, posterosuperior rotator cuff tears are classified and treated according to the geometric system, which allows tear pattern recognition to guide the repair pattern. Partial-thickness posterosuperior tears are classified by size and morphology according to Ellman. Both full- and partial-thickness subscapularis tears are common, and the typical pathoanatomical features exhibited by these tears should allow for increased recognition by surgeons. The capsuloligamentous tissue of the rotator interval commonly known as the comma should be used to guide the surgeon to retracted subscapularis tendon tears and should be preserved during repair. Preoperative findings may heighten the suspicion for occult or interstitial rotator cuff tears, and specific arthroscopic exam techniques allow for diagnosis of these lesions.