Shortcuts in arthroscopic knot tying: do they affect knot and loop security?

Area of Science:

• Orthopedic Surgery
• Biomechanical Engineering
• Surgical Knot Tying

Background:

• Arthroscopic surgery often utilizes sliding knots, with Tennessee slider knots being common.
• Shortcut techniques for tying reversed half-hitches on alternating posts (RHAPs) are used but lack biomechanical validation.
• These shortcuts involve manipulating strand tension to 'flip' the knot.

Purpose of the Study:

• To biomechanically evaluate the security of arthroscopic surgical knots tied using different techniques.
• To determine if shortcut knot-tying methods affect knot security and loop security compared to traditional methods.

Main Methods:

• A controlled laboratory study involving a single surgeon tying 90 No. 2 FiberWire knots.
• Knots were created with either a static surgeon's knot base or a Tennessee slider base.
• Three tying techniques were compared: standard rethreading, and two shortcut methods involving 'flipping' the knot using past-pointing and/or over-pointing.
• Knot security was assessed through cyclic loading and load-to-failure testing.

Main Results:

• Surgeon's knots demonstrated superior security, with lower slippage and failure rates, and higher ultimate failure loads compared to Tennessee knots.
• Shortcut techniques did not negatively impact surgeon's knot properties.
• For Tennessee knots, shortcut methods (past-pointing and over-pointing) significantly decreased load to failure and increased slippage and catastrophic failure rates.
• Loop security showed marginal improvement with shortcut techniques.

Conclusions:

• Surgeon's knots provide greater security than Tennessee sliding knots in biomechanical testing.
• Shortcut tying methods do not compromise surgeon's knot security.
• The use of shortcut techniques with Tennessee sliding knots leads to unacceptable knot slippage and failure, potentially compromising arthroscopic repair outcomes.