Biomechanical Evaluation of Flexor Tendon Repair Using Barbed Suture Material: A Comparative Ex Vivo Study

Abstract

Barbed suture material for tendon repair opens up the possibility of a knotless reconstruction due to an increased suture-tendon interaction. The aim of this study was to compare the tensile strength of a knotted technique with a monofilament polydioxane suture to that of a knotless technique with a barbed suture material, by using a multistrand, modified Kirchmayr-Kessler tenorrhaphy. Sixty human flexor digitorum tendons were randomized into 4 groups. A modified, knotted, multistrand Kirchmayr-Kessler technique with an absorbable, monofilament polydioxane suture was compared with a modified, knotless, multistrand Kirchmayr-Kessler technique with an absorbable, unidirectional barbed glycolic-carbonate suture. Tendons were distracted to failure. Mode of failure and load to failure were recorded. The knotless 2-strand Kirchmayr-Kessler barbed suture shows a significantly lower tensile strength than the knotted 2-strand polydioxane suture (p < .001). The comparison of the maximum tensile strength of the knotless (glycolic-carbonate) technique with that of the knotted (polydioxane) 4-strand technique resulted in no significant difference in either technique utilized (p = .737). The tensile strength of the 4-strand technique was greater than that of the corresponding 2-strand technique (p < .001). The 2-strand Kirchmayr-Kessler barbed suture proved to be insufficient and significantly weaker than the 2-strand polydioxane suture, and therefore it cannot be recommended. With the knotless 4-strand Kirchmayr-Kessler technique, the barbed suture material has the potential to be used in flexor tendon surgery, but it has no advantage over the 4-strand polydioxane suture.