Abstract
Among lesions of the rotator cuff, subscapularis tendon tears are one of the less common injuries and mostly occur in combination with additional lesions of the posterosuperior rotator cuff and the long biceps tendon. If a subscapularis tendon rupture is suspected in the initial clinical testing, the primary diagnostics should include modern cross-sectional magnetic resonance imaging to assess the tendon lesion and to detect concomitant pathologies. Nevertheless, subscapularis tendon lesions are often initially overlooked and first correctly diagnosed during shoulder arthroscopy.