Fig. 4

a Intraoperative arthroscopy shows the anteromedial retraction of the superficial layer (s) in a delaminated rotator cuff tear (the same case as in Fig. 1). b The retracted superficial layer was reduced posterolaterally with a tissue grasper. c The illustration shows that the anterosuperior rotator cuff is detached from the greater tuberosity (red line) and the tear progressed into the cuff substance, leading to longitudinal splitting through the supraspinatus or infraspinatus (blue line). d A larger proportion of the supraspinatus (SSP > ISP) in the superficial layer causes anteromedial retraction (type S2) (dotted line elongated rotator interval tissue, red circle end of cuff tear, SSP supraspinatus, ISP infraspinatus, GT greater tuberosity, LT lesser tuberosity, ISP-I footprint of the infraspinatus [7], SSP-I footprint of the supraspinatus [7])