We use a 3.0-mm acellular dermal allograft (ArthroFlex; Arthrex) to reconstruct the superior capsule. The positions of the 4 anchors are carefully marked on the dermal allograft. We routinely add an additional 5 mm of tissue to the medial, anterior, and posterior margins to decrease the risk of suture cut out. An additional 10 mm of tissue is added laterally to cover the greater tuberosity. The final contoured graft is typically trapezoidal in shape.
The sutures from the 4 anchors are then sequentially retrieved through the lateral cannula. The sutures from the greater tuberosity anchors are passed through their respective holes in the graft. However, the suture limbs from each of the glenoid anchors are individually passed 2 mm anterior and 2 mm posterior to their respective marks on the graft with an antegrade suture passer (Figure 3). It is important to have an assistant apply tension to each of the sutures after they are passed through the graft to decrease the chance of crossing and tangling the sutures.
The eyelets of the medial anchors are utilized as pulleys to deliver the dermal allograft into the shoulder. One suture limb from each of the glenoid anchors is tied to the other over a switching stick (Figure 4A). The 2 remaining (untied) suture limbs are then pulled, which introduces the graft to the orifice of the cannula (Figure 4B). A tissue grasper is then used to fold the dermal allograft along its long axis and introduce the graft into the joint (Figure 4C). Once the medial portion of the graft is positioned onto the superior glenoid the 2 remaining (untied) suture limbs are tied to each other as a static knot in the subacromial space (Figure 4D).
The redundancy in the suture tapes can be removed by sequentially sliding a retriever down each suture and tensioning the suture as the nose of the instrument pushes the dermal graft down to the tuberosity bone bed. The suture tapes are crisscrossed and secured laterally with 2 additional knotless threaded anchors (Figure 5). One may also place cinch stitches at the anterolateral and posterolateral corners of the graft that are incorporated into the lateral anchors. These sutures can be useful for pulling the graft back out of the subacromial space in the event of any suture tangles, and can be used for controlling the lateral aspect of the graft during lateral anchor placement.