H-Loop Knotless Double-Row Repair Versus Krackow Repair for Achilles Tendon Rupture: A Biomechanical Study in a Cadaveric Model

Background: Surgery is widely recognized as an effective treatment for Achilles tendon rupture; however, there remains debate regarding the optimal surgical approach. Purpose: To compare the biomechanical properties of 2 techniques, the H-loop knotless double-row (HLDR) suture repair and the Krackow suture repair, for Achilles tendon rupture in a cadaveric model. Study Design: Controlled laboratory study. Methods: Ten matched Achilles tendon specimens from 5 male and 5 female donors were obtained. Each specimen from a matched pair was randomly distributed to 1 of 2 repair groups, the HLDR group or the Krackow group. Tendon elongation was recorded after exposure to 10, 100, 200, 400, 600, 800, and 1000 load cycles. The gap distance after application of a 100-N force, the force needed to produce a 2-mm gap, and the load to failure were measured. All biomechanical properties were compared between the HLDR and Krackow groups using the paired t test. Results: The HLDR group consistently exhibited significantly less elongation than the Krackow group after exposure to the 7 load cycles (P < .01 for all). In addition, the HLDR group exhibited a significantly smaller gap distance after applying a 100-N force (0.30 +/- 0.02 vs 8.10 +/- 0.46 mm for Krackow group), required significantly more force to generate a 2-mm gap (419.68 +/- 39.48 vs 22.29 +/- 3.40 N for the Krackow group), and had a significantly higher ultimate failure load (519.91 +/- 57.29 vs 220.30 +/- 19.27 N for the Krackow group) (P < .01 for all). Conclusion: The study findings demonstrated that the HLDR technique had more advantages compared with the Krackow technique with regard to elongation after different cyclic loadings, gap distance after a 100-N load, force needed to produce a 2-mm gap, and load to failure in a cadaveric model. Clinical Relevance: The HLDR technique could be a viable option for Achilles tendon rupture repair.