The «RoC» suture technique to allow early active rehabilitation in flexor tendon repair: a biomechanical study

International audiencePurpose. Current flexor tendon repair techniques do not provide sufficient tensile strength to allow immediate active unprotected rehabilitation. The «RoC» repair, a new 4-strand suture technique, is proposed to improve biomechanical properties, combining a high tensile strength and a low gliding resistance without causing suture pullout by tendon laceration. Our hypothesis is that the RoC technique can reach an ultimate tensile strength of 140N, and a higher tensile strength than the Adelaide technique. Methods. Four groups of 10 porcine flexor tendons were sutured with the RoC or Adelaide technique, and with a 3-0 Polypropylene or Dyneema suture. An axial traction test to failure (Instron machine) was administrated to each tendon to measure ultimate tensile strength. Results. With the Dyneema suture, median ultimate tensile strength was 145N for the RoC technique and 80N for Adelaide (p < 0.01). RoC tendons were 1.8 times more resistant than Adelaide tendons with the Dyneema suture, and 1.2 times more resistant with Polypropylene. Conclusion. Tendons repaired with the RoC technique and Dyneema suture exceeded a tensile strength of 140N. The ultimate tensile strength was superior to that of Adelaide technique regardless of the suture material