Evaluation of high-strength orthopedic sutures: a head-to-head comparison

The goal of this study was to determine whether a difference in cycles to failure or mode of failure would be observed among specimens of 3 high-strength suture materials, and whether different suture configurations would affect knot security. Ten representative specimens of Ethibond (Ethicon, Inc, Somerville, New Jersey), FiberWire (Arthrex, Inc, Naples, Florida), MaxBraid (Biomet, Inc, Warsaw, Indiana), and Orthocord (DePuy Orthopaedics, Warsaw, Indiana) were tied in 6 different knot configurations commonly used in orthopedic procedures. Each specimen was cyclically loaded between 9 and 180 N at a rate of 1 Hz until the specimen failed or reached a maximum of 3500 cycles. Each suture material was subjected to tensile loading until failure at a rate of 1.25 mm/s. The 3 most secure knots all included the 3 reverse half-hitch on alternating posts (3-RHAP) configuration. All specimens tied with these 3 knot types failed by suture rupture. All knots using the overhand with 3 of the same half-hitches on the same post (O-3SHSP) configuration failed by knot slippage regardless of suture material. When the 3 strongest knots were combined, FiberWire resisted a significantly greater number of fatigue cycles than Orthocord or MaxBraid. In the single load to failure tests, Orthocord, FiberWire, and MaxBraid all had significantly higher ultimate strength than Ethibond. Knots using the 3-RHAP configuration provide security superior to that of those without this configuration. All 3 high-strength sutures tested outperformed Ethibond in single load to failure testing, with FiberWire resisting the greatest number of cycles. Postoperative strength and reliability of a soft tissue repair is inherently dependent on the properties of the suture materials used.