Pulley Kantor suture, double set-back suture, double set-back dermal suture
Video 4-18. Pulley set-back dermal suture
This technique is best used in areas under very significant tension. In addition to high-tension wounds in general, areas under marked tension that are prone to wound inversion, such as the back and chest, may be well-served utilizing this technique.
Wounds under marked tension may be challenging to close even with well-placed buried sutures. The pulley set-back dermal suture technique relies on the pulley effect of multiple loops of suture to permit the closure of wounds under even significant tension. In addition, the locking effect of placing a double loop of suture leads the suture material to lock in place after the first throw of the surgical knot, obviating the need for an assistant maintaining the alignment of the wound edges.
Suture choice is dependent in large part on location. Though this technique is designed to bite the deep dermis and remain buried well below the wound surface, the surgeon may choose to utilize a larger gauge suture than would be used for an equivalently placed pulley buried dermal suture. Using a 2-0 absorbable suture on the back with this technique results in only vanishingly rare complications, since the thicker suture remains largely on the underside of the dermis, and suture spitting is an uncommon occurrence. On the extremities, a 3-0 or 4-0 absorbable suture material may be used, and on the face, if this pulley approach is needed at all, a 5-0 absorbable suture is adequate. Braided suture tends to lock more definitively than monofilament, though monofilament suture allows for easy pull through when taking advantage of the pulley effect.
The wound edge is reflected back using surgical forceps or hooks. Adequate visualization of the underside of the dermis is required.
While reflecting back the dermis, the suture needle is inserted at 90 degrees into the underside of the dermis 2-6 mm distant from the incised wound edge.
The first bite is executed by traversing the dermis following the curvature of the needle and allowing the needle to exit closer to the incised wound edge. Care should be taken to remain in the dermis to minimize the risk of epidermal dimpling. The needle does not, however, exit through the incised wound edge, but rather 1-4 mm distant from the incised edge. The size of this first bite is based on the size of the needle, the thickness of the dermis, and the need for and tolerance of eversion.
Keeping the loose end of suture between the surgeon and the patient, the dermis on the side of the first bite is released. The tissue on the opposite edge is then reflected ...