Comparison of the cheese-wiring effects among three sutures used in rotator cuff repair

PURPOSE: The goal of this study was to compare the cheese-wiring effects of three sutures with different coefficients of friction. MATERIALS AND METHODS: Sixteen human cadaveric shoulders were dissected to expose the distal supraspinatus and infraspinatus muscle tendons. Three sutures were stitched through the tendons: #2 Orthocord(™) suture (reference #223114, DePuy Mitek, Inc., Raynham, MA), #2 ETHIBOND* EXCEL Suture, and #2 FiberWire(®) suture (FiberWire(®), Arthrex, Naples, FL). The sutures were pulled by cyclic axial forces from 10 to 70 N at 1 Hz for 1000 cycles through a MTS machine. The cut-through distance on the tendon was measured with a digital caliper. RESULTS: The cut-through distance in the supraspinatus tendons (mean ± standard deviation, n = 12) were 2.9 ± 0.6 mm for #2 Orthocord(™) suture, 3.2 ± 1.2 mm for #2 ETHIBOND* suture, and 4.2 ± 1.7 mm for #2 FiberWire(®) suture. The differences were statistically significant analyzing with analysis of variance (P = 0.047) and two-tailed Student's t-test, which showed significance between Orthocord(™) and FiberWire(®) sutures (P = 0.026), but not significant between Orthocord(™) and ETHIBOND* sutures (P = 0.607) or between ETHIBOND* and FiberWire(®) sutures (P = 0.103). CONCLUSION: The cheese-wiring effect is less in the Orthocord(™) suture than in the FiberWire(®) suture in human cadaveric supraspinatus tendons. CLINICAL RELEVANCE: Identification of sutures that cause high levels of tendon cheese-wiring after rotator cuff repair can lead to better suture selection.