Related Experiment Video
Updated: May 10, 2025

A Training and Testing System for Performing Vascular Reconstruction In Vitro
Published on: October 26, 2019
Using Millimeter Measurements and Force Gauges to Test the Security of Knots Tied by Residents Before and After
Thomas J O'Keefe1, Louis A Perkins2, John Austin2
1University of California San Francisco Department of Surgery, San Francisco, CA, USA.
Abstract:
IntroductionInsecure surgical knots can be responsible for a wide range of complications, ranging from fascial dehiscence to fatal exsanguination. Most surgeons are unfamiliar with the principles underlying the security of the commonly tied half-hitch knot. We aimed to identify whether the security of half-hitch knots tied by surgical residents could be improved by watching online educational videos.MethodsTen categorical general surgery residents tied 20 knots before and 20 knots after viewing 2 online educational videos on half-hitch knots. All knots were tied in a simulated cavity. The time of tying, knot apposition, and knot security were compared before and after viewing the videos.ResultsAll residents tied single-post half-hitch knots before viewing the videos and alternating-post half-hitch knots after viewing the videos. The mean securities of the silk (8.9 vs 40.4 N, P < 0.0001) and nylon (8.3 vs 12.1 N, P < 0.0001) knots to 3 mm increased significantly after viewing the didactic videos. The mean tying time for silk knots before viewing the videos was 24.3 seconds, and the mean tying time after viewing the videos was 28.0 seconds (P = 0.001). Before viewing the video, 180/200 (90%) knots were apposing and after 171/199 (85.9%) were apposing (P = 0.18).ConclusionsViewing of publicly available online educational knot-tying videos by surgical residents was associated with a clinically relevant and statistically significant increase in knot security. Knots tied after viewing the videos took significantly longer to tie.
More Related Videos
07:53Standardized Rat Coronary Ring Preparation and Real-Time Recording of Dynamic Tension Changes Along Vessel Diameter
Published on: June 16, 2022
07:15A Testing Platform for Durability Studies of Polymers and Fiber-reinforced Polymer Composites under Concurrent Hygrothermo-mechanical Stimuli
Published on: December 11, 2014
Related Concept Videos
Measurements of Strain
Mechanical Characteristics of Steel
The tension test is fundamental for determining tensile strength. In this test, a steel specimen is stretched using a gripping device until it breaks. The data collected during this test are used...