Biomechanics Study of the Holding Power between Tendon and Suture Using Different Techniques

Background: The holding power of a repaired flexor tendon injury is related to surface sutures, suture material and different techniques. Nowadays, a barbed suture material offers the possibility of knotless flexor tendon repair but many hospitals use non-barbed suture materials. The purpose of this study was to compare a barbed suture material and a non-barbed suture material for primary stability under static loading and increased knots in the non-barbed suture material (knot technique) for increased holding power of tendons in animal testing. Methods: Forty-five fresh porcine tendons were randomized into three groups: Group 1 (grasping technique group) used a four-strand core suture grasping a four-strand modified Kessler suture by non-barbed suture material [Non-absorbable monofilament polybutester 3-0] was used to repair the tendon with a surgical knot; in Group 2 (knot technique group) a four-strand core suture used the knot technique by non-barbed suture material [Non-absorbable monofilament polybutester 3-0] to repair the tendon with a continuous suture adding surgical knots in the same place as the surgical knot at the repair sites; and Group 3 (knotless technique group) used a four-strand core suture with the knotless technique in modified Kessler suture with barbed suture material [Non-absorbable monofilament polybutester 3-0] to repair the tendon without a knot. Our objective was to compare the ultimate tensile strength between the groups. Results: The mean tensile strength was 30.38 ± 5.04 N for group 1, 41.71 ± 2.62 for group 2 and 47.53 ± 4.89 for the group 3. The ANOVA test revealed a significant difference among the various techniques (p < 0.05). The highest tensile strength was found in the knotless technique using barbed suture material group. Conclusions: The knotless technique using barbed suture material demonstrated the highest tensile strength in suture repairs. The maximum tensile strength was significantly higher in this group.