A Quick and Simple Four-Strand Barbed Suture Repair Technique for Flexor Tendons: A Comparison to a Traditional Four-Strand Monofilament Repair

Abstract

Background: Barbed suture technology has shown promise in flexor tendon repairs as there is an even distribution of load and the need for a knot is eliminated.  We propose that a quick and simple, novel, barbed technique without any exposed barbs on the tendon surface, has comparable strength and a smaller cross-sectional area at the repair site than traditional methods of repair.

Methods: Forty fresh porcine flexor tendons were randomized to polybutester four-strand barbed repair (Figure 2) or to four-strand Adelaide monofilament repair (Figure 1).  The cross-sectional area was measured before and after repair.  Biomechanical testing was carried out and 2mm gap formation force, ultimate strength of repair and method of failure were recorded.

Results: The mean ultimate strength of the barbed repairs was 54.51±17.9 whilst that of the Adelaide repairs was 53.17 ± 16.35.  The mean 2mm gap formation force for the barbed group was 44.71 ± 17.86 whereas that of the Adelaide group was 20.25 ± 4.99.  The post-repair percentage change in cross-sectional area at the repair site for the Adelaide group and barbed group was 12.0 ± 2.3 and 4.6 ± 2.8 respectively.

Conclusions: In our ex vivo study on flexor tendons, a four-strand knotless, barbed method attained comparable strength to that of the traditional Adelaide repair technique. The barbed method had a significantly reduced cross-sectional area at the repair site compared to the Adelaide group.  Furthermore, the 2mm gap formation force was less in the barbed group than the Adelaide group.  Barbed repairs show promise for flexor tendon repairs this simple and quick method warrants further study in an animal model.

Figure 1. The four-strand Adelaide repair.

Figure 2. Diagram of the four-strand knotless barbed repair. The blue arrows represent the direction the barbed suture passed through the tendon.