Does Barbed Suture Repair Negate the Benefit of Peripheral Repair in Porcine Flexor Tendon?

Background: Advances in suture material and geometry have fueled interest in barbed suture tenorrhaphy. Theoretically, barbed suture allows better load distribution, smoother gliding under pulleys, and improved tendon blood flow. Minimal data exist on whether barbed tendon repair may benefit from supplementation by a peripheral stitch. The purpose of this study is to determine whether peripheral suture repair increases gap resistance in both conventional and barbed core repairs, increases maximum tensile strength, and fails before or after the core repair. Methods: Porcine flexor tendons were harvested and assigned randomly into 4 groups of 10 of varying suture constructs (3-0 PDS™ or 3-0 V-Loc 180™ core with or without peripheral 5-0 Vicryl™ repair). Core repairs were performed using a modified 4-strand cruciate repair. A servohydrolic tester was used for biomechanical testing of linear 2-mm gap resistance and maximum tensile strength. Results: Peripheral repair improved 2-mm gap resistance in all repairs, regardless of core suture type, conventional (173% increase) or barbed (204% increase). No change in the maximum tensile strength was found in either core suture type with peripheral repair. Peripheral repairs always failed before core repairs, at a significantly higher load of 74.2 ± 20.4 N in barbed versus 57.8 ± 12.2 N ( P = .04) in conventional core repairs. Conclusions: The addition of peripheral repair improved gap resistance but not ultimate tensile strength in both conventional and barbed flexor tendon repairs in linear testing. The 4-strand cruciate flexor tendon repairs using barbed suture may require peripheral repair to withstand physiologic loads, as core repair alone using barbed suture was insufficient.