Improved time-zero biomechanical properties using poly-L-lactic acid graft augmentation in a cadaveric rotator cuff repair model

Hypothesis: Rotator cuff repair failure rates range from 20% to 90%, and failure is believed to occur most commonly by sutures cutting through the tendon due to excessive tension at the repair site. This study was designed to determine whether application of a woven poly-L-lactic acid device (X-Repair; Synthasome, San Diego, CA) would improve the mechanical properties of rotator cuff repair in vitro. Materials and methods: Eight pairs of human cadaveric shoulders were used to test augmented and non-augmented rotator cuff repairs. Initial stiffness, yield load, ultimate load, and failure mode were compared. Results: Yield load was 56% to 92% higher and ultimate load was 56% to 76% higher in augmented repairs. No increase in initial stiffness was found. Failure by sutures cutting through the tendon was reduced, occurring in 17 of 20 non-augmented repairs but only 7 of 20 augmented repairs. Conclusions: Our data show that application of the X-Repair device significantly increased the yield load and ultimate load of rotator cuff repairs in a human cadaveric model and altered the failure mode but did not affect initial repair stiffness. Level of evidence: Basic Science Study. (C) 2010 Journal of Shoulder and Elbow Surgery Board of Trustees.