Locking Stitch Techniques Demonstrate Improved Biomechanical Performance in Cadaveric Midsubstance Achilles Tendon...

Area of Science:

• Orthopedic Surgery
• Biomedical Engineering
• Sports Medicine

Background:

• Achilles tendon (AT) repair demands high failure load and minimal elongation.
• Midsubstance AT repairs rely on suture techniques like whip stitch or Krackow stitch.
• Enhanced techniques aim to simplify surgery and improve biomechanics.

Purpose of the Study:

• Evaluate biomechanical properties of three enhanced midsubstance AT repair techniques.
• Hypothesize that locking stitch constructs improve biomechanical performance over nonlocking ones.
• Compare constructs based on elongation and failure load.

Main Methods:

• 30 cadaveric lower leg specimens with simulated AT ruptures were used.
• Repairs included whip stitch with gift box (WG), locking whip stitch with gift box (LG), and Krackow stitch with epitendinous baseball (KB) stitch.
• Specimens underwent cyclic loading (20-100 N for 1000 cycles) followed by load to failure.

Main Results:

• The Krackow epitendinous baseball stitch (KB) showed significantly lowest cyclic elongation.
• The locking whip stitch gift box (LG) demonstrated the significantly highest failure load.
• LG achieved higher failure load with less suture material than KB; all whip stitch groups failed via tissue pull-through.

Conclusions:

• The locking whip stitch gift box (LG) and Krackow epitendinous baseball stitch (KB) techniques improve AT repair failure load and limit elongation, respectively.
• Both LG and KB locking stitch techniques showed significant biomechanical improvements over the nonlocking whip stitch with gift box (WG).
• The nonlocking whip stitch gift box (WG) technique is not recommended for AT repair due to insufficient fixation.