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Influence of pulling direction on knot security: A laboratory research
Hong-Feng Guo1, Xiao-Yu Hou1, Wei-Wei Dai1
1Department of Basic Operative Surgery, College of General Medicine, The First Affiliated Hospital of Army Medical University, China.
Asian Journal of Surgery
|September 28, 2023
Summary
Surgeons should alternate pulling directions when tying surgical knots for enhanced security. Tying knots in a constant direction leads to weaker knots, potentially compromising patient safety.
Area of Science:
- Surgical techniques
- Biomechanical analysis of surgical knots
Background:
- Surgeons often overlook the direction of pull when creating surgical knots.
- The influence of pulling direction on knot security is not well understood.
Purpose of the Study:
- To investigate the impact of pulling direction on the security of surgical knots.
- To compare knot security when throws are pulled in alternate versus constant directions.
Main Methods:
- 368 residents tied surgical knots (2-7 throws) using 3-0 gauge braided silk suture.
- Knots were categorized based on pulling direction: alternate (Group A) or constant (Group C).
- Tensile strength and untying rates were measured for comparative analysis.
Main Results:
- Knots tied with alternate pulling directions (Group A) demonstrated significantly higher tensile strength than those tied with constant direction (Group C).
- Group A knots exhibited a significantly lower untying rate for 5-7 throws compared to Group C.
- Unraveled knots from Group A showed significantly greater tensile strength than those from Group C.
Conclusions:
- Constant pulling direction during knot tying compromises knot security.
- Surgeons should utilize alternate pulling directions to achieve superior knot security.
- Optimizing knot tying technique can enhance patient safety by reducing the risk of knot failure.
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