Mechanical and Handling Properties of Braided Polyblend Polyethylene Sutures in Comparison to Braided Polyester and Monofilament Polydioxanone Sutures

Abstract

This study was designed to comprehensively compare the mechanical properties of 4 types of braided polyblend sutures with widely used braided polyester and monofilament polydioxanone sutures. Polyblend polyethylene sutures (FiberWire [Arthrex, Naples, FL], Herculine [Linvatec, Largo, FL], Orthocord [DePuy Mitek, Raynham, MA], and Ultrabraid [Smith & Nephew Endoscopy, Andover, MA]), a braided polyester suture (Ethibond; Ethicon, Somerville, NJ), and an absorbable monofilament polydioxanone suture (PDS II; Ethicon), all USP No. 2, were mechanically tested. Fraying resistance was tested on eyelets of metallic and absorbable suture anchors. Cartilage abrasion caused by an intra-articularly placed suture knot was simulated by fraying on distal porcine femora. All polyblend sutures were stronger than Ethibond or PDS II sutures by at least a factor of 2, with or without a knot. When knotted, Herculine (261 +/- 44 N) was strongest, followed by Ultrabraid (244 +/- 3 N). FiberWire was most resistant against fraying on metallic anchors. Orthocord was by far least abrasive with absorbable anchors. Resistance to fraying was 100- to 500-fold (absorbable anchors) and 6- to 30-fold (metallic anchor) better for all polyblend sutures than for Ethibond. All braided sutures caused a similar amount of abrasion of joint cartilage, but they caused significantly more abrasion (>20-fold) than the monofilament degradable suture. The ultimate strength of polyblend suture material was 2- to 2.5-fold greater than that of polyester or polydioxanone sutures, but the resistance to fraying was up to 500-fold greater than that of polyester or polydioxanone sutures. With regard to strength, this makes polyblend sutures particularly advantageous for use with metallic edges of anchors or prostheses or with absorbable anchor eyelets. With a high resistance to fraying against metallic edges or a decrease in cutting of absorbable suture eyelets being up to 500-fold greater than with polyester or polydioxanone sutures, the new polyblend sutures appear to fill a void in the armamentarium of the surgeon, provided that at least 2 throws more than with conventional sutures are used for knot tying.