The purpose of this study is to evaluate the tensile strength and repair-site profile of flexor tenorrhaphy using commercially available barbed sutures.
Cadaveric FDP tendons were randomized for repair using 1) 2-0 polypropylene barbed suture with either 3 strand or 6 strand knotless repair; 2) four- strand locked cruciate repair using 4-0 monofilament polypropylene, 3) 4-0 braided polyester suture, or 4) 4-0 composite polyethylene and braided polyester suture. The repaired tendons were linearly distracted until mechanical failure and visually evaluated.
The results indicate that the 3 strand and 6 strand knotless barbed suture tenorrhaphy techniques resulted in less bunching and smaller mean cross-sectional areas as compared with controls. Additionally, the 3 strand barbed suture technique had comparable tensile strength compared to controls; whereas, the 6 strand technique demonstrated significantly greater tensile strength. The mode of failure for the barbed suture knotless repair was suture breakage while controls failed by means of suture pull-out or knot rupture.
Current flexor tendon suture repair techniques carry inherent limitations. The absolute need for knots limits tensile strength and locking suture loops causes bunching which may impede tendon gliding through the fibrosseous tunnels. The concept of barbed suture tenorrhaphy carries the promise of a strong knotless tendon repair that limits bunching and evenly distributes tension. This concept was first studied in the 1960’s; however, due to limited materials this never gained popularity. This is the first article to study the commercially available modern barbed sutures. In this well designed biomechanical study, the authors nicely demonstrate the advantages of the barbed suture repair technique. Their results warrant in vivo testing to evaluate the clinical applicability of this concept.