On the technique of Roeder ’s extracorporeal sliding knot tying

Abstract

Roeder’s extracorporeal sliding knot is an available, safe, and economic alterative to clipping and stapling in some video-assisted endoscopic procedures, including securing appendiceal stump in laparoscopic appendectomy. Technical illustration of 4S-modified Roeder’s knot tying is presented, as well as links to original videos. Repair security depends on inability of the knot to slip back after tightening of the loop. This feature may be provided by tying minimum of three additional reversed half-hitches on alternating poles, or by interchanging of knot geometry. Purely sliding knots do not possess any internal locking mechanism. According to geometry interchanging mechanism sliding knots are classified into jamming and retrograde or antegrade locking ones. The concept of knots that only allowed sliding in distal direction (ratchet knots) lacks any conclusive geometrical basis. There is a lack of published sliding knots tying technical instructions both among texts and video demonstrations. Frequently knot geometry forming sequence only is discussed, and modes with undependable thread holding are recommended. So abilities of selftraining are scant. Undependable thread holding during some moments of surgical knot tying increases risk of thread slipping out of fingers, time loss, and technique digression with origin of accidental modifications. Uncontrolled usage of sliding knots modifications with unknown biomechanics may result in failure of the procedure and should be avoided in clinical practice.