Comparison of Knot Tying in Robotic, Laparoscopic, and Open Surgery: Robotic Knots as Tight as, but More Secure than, Open Knots

Abstract

Objective: Robotic surgery may have many potential benefits for the surgeon. In an effort to evaluate the surgical performance, standard laparoscopy, DaVinci robot (Intuitive Surgical, Sunnyvale, CA), and standard open knot tying by two experienced gynecologic surgery trainees, were compared. Design, Materials, and Methods: Two gynecologic surgeons who were trained in laparoscopic surgery were asked to tie knots with 2-0 VICRYL™ sutures under controlled conditions using the DaVinci robot, a laparoscopic simulator stack, and by hand. The procedures were filmed and timed, and the knots collected for further testing using a tensiometer. The tensiometer was used to check the tightness and security of the knot. Results: The robotic knots (p=0.021) and open knots (p=0.0001) were both significantly tighter than the laparoscopic knots. The open knot tying was much faster than either the robotic or the laparoscopic knot tying. There was no statistically significant difference between the laparoscopic and robotic knot ties. There was no statistical difference in security in robotic versus laparoscopic knots or in laparoscopic versus open knots. The robotic knots were more secure than the open knots (odds ratio=0.351; 95% confidence interval [CI]=0.152–0.814). Conclusions: Robotic knot tying was as quick as and tighter than laparoscopic knot tying, and more secure but slower than open tying. The lack of haptic feedback can lead to snapped knots as a result of excessive force. (J GYNECOL SURG 26:287)