Is Nice knot suture comparable to wire for cerclage fixation? A biomechanical performance study

Area of Science:

• Orthopedic Surgery
• Biomedical Engineering
• Materials Science

Background:

• Cerclage fixation is crucial for circumferential augmentation in orthopedic procedures, especially when screw fixation is not feasible.
• Advances in suture materials and knotting techniques necessitate comparative analysis against traditional methods like monofilament wire.
• Existing evidence comparing novel suture techniques with wire for cerclage is limited.

Purpose of the Study:

• To evaluate and compare the strength and durability of cerclage fixation using the Nice knot suture technique versus monofilament wire.
• To investigate the mechanical properties of different cerclage fixation methods under static and dynamic loading conditions.

Main Methods:

• Compression load testing using a Jamar Hydraulic Hand Dynamometer and distraction testing with an Instron system were performed.
• The Nice knot was constructed using number 2 and number 5 FiberWire and compared against monofilament wire constructs.
• Key outcomes included clinical and absolute failure, maximum compression, and sustained compression over time.

Main Results:

• Double-stranded monofilament wire provided the highest compression (90 kg), followed by single-stranded (60 kg).
• Number 5 FiberWire demonstrated comparable maximum compression to single-stranded wire but lower than double-stranded wire.
• The Nice knot with number 5 FiberWire exhibited a stiffer, more linear tension relationship and a higher load to failure than monofilament wire constructs, with failure occurring at the suture interface.

Conclusions:

• The Nice knot suture technique presents a viable alternative for cerclage fixation in orthopedic surgery.
• This technique shows promising mechanical properties, particularly in load-to-failure scenarios, making it suitable for long-bone fracture fixation.