The Oklahoma repair technique: a biomechanical study of a new suture repair technique.

We designed and evaluated the biomechanical advantages of a new (Oklahoma) suture technique for repairing flexor tendons in fresh, frozen cadaver specimens. Forty flexor digitorum profundi tendons from the middle three fingers were sharply cut and repaired with a number 3-0 braided polyester using the new technique and the Modified Kessler technique with and without an epitenon repair. The repaired tendons were then stressed to failure. The Modified Kessler with epitendon repair initiated gap formation on an average of 15.3 +/- 2.7 newtons and failed at 40.9 +/- 4.3 newtons. The Oklahoma suture technique with a running epitenon repair initiated gap formation on average of 48.6 (SD +/- 4.0) newtons and required an average load of 57.9 (SD +/- 3.0) newtons to fail. Thus, it was significantly stronger than the modified Kessler technique with epitendon repair (P < 0.01). The tendons repaired with the Oklahoma and epitenon repair suture technique did not form a 2 mm gap prior to failure. The epitendon repair increased the resistance to gap formation by 80% to 100% and the repair failure by 17.5% to 25% for both types of repairs. We concluded that the addition of the epitendon repair increases the tensile strength of the repair regardless of the core suture technique, and it should be used. In comparison with the Modified Kessler repair technique, the Oklahoma repair technique has superior tolerance to gap initiation, 2 mm gap formation, and physical failure of the repaired tendon.