# Biomechanical comparison of tendon repair techniques: Bunnell suture leads in mode of failure and minimally invasive configuration in elongation

## TL;DR

This study compares different tendon repair techniques to determine their biomechanical strengths and weaknesses for surgical decision-making.

## Contribution

The study provides empirical biomechanical evidence comparing four tendon repair techniques, focusing on mode of failure and elongation.

## Key findings

- The Bunnell suture technique showed the best performance in terms of mode of failure.
- The MIC suture technique outperformed others in tension/construct elongation at specific load points.

## Abstract

In this experimental study, the Minimally Invasive Configuration (MIC), the Bunnell, Kessler and modified Bunnell–Kessler techniques for tendon rupture repair were compared in terms of the following biomechanical parameters: maximum load, mode of failure, failure elongation, tension/construct elongation and stiffness (Young's modulus). The scope of comparison involves understanding the properties of each suture technique in hopes of eventually contributing to surgical decision‐making.

Thirty‐two frozen ovine specimens were obtained, and transverse tenotomy was performed on each. Eight tendons were randomly allocated to each technique. Specimens were tested performing a unidirectional tensile load to failure using a servo‐hydraulic testing device. The tendons were also loaded to failure at a rate of 10 mm/s. The total length of the construct was defined as the distance from the two clamps. Stiffness was calculated by determining the slope of the force–displacement curve in the linear region. Total failure was defined as a drop of measured force or rupture of the tendon–suture complex.

In the mode of failure, Tukey's post hoc test showed a statistically significant difference between the Bunnell group and the other three groups (p < 0.05). For Tension/construct elongation at 5 and 10 mm, Tukey's post hoc test showed a statistically significant difference between the MIC group and the other three groups (p < 0.05). At 15 mm Tukey's post hoc test showed a statistically significant difference between the MIC group and the Kessler group (p < 0.05).

The Bunnell suture performed best in terms of mode of failure, while the MIC suture technique outperformed the rest in terms of tension/construct elongation. Findings show sufficient biomechanical evidence to support the ongoing clinical application of all techniques.

Level V.