Does Suture Type or Configuration Matter in Percutaneous Achilles Tendon Repairs?

Abstract

Category: Trauma; Sports Introduction/Purpose: The human Achilles tendon is functionally important for dynamic activities and is a common site of injury, resulting in pain, weakness, and removal from sport. While treatment options vary and the opinions regarding optimal management are not uniform, percutaneous repair through commercially available guides is one option that has been used in the United States. The purpose of this study was to test the mechanical properties of four suture permutations. Methods: This biomechanical study included Porcine toe flexor tendons as an analogue for the human Achilles tendon. Simulated rupture was performed and tendons repaired using a percutaneous guide. Technique was uniform with pre-determined allotment into one of four groups based on suture configuration (single or double locked) and type (round or flat) with a total of 10 specimens in each group. Specimen then underwent static creep test, a dynamic load creep test, and finally load to failure test. An analysis of variance test was performed, followed by pairwise comparisons using independent t-tests to assess inter-group differences if significant effects were found, adjusted for multiple comparisons. Results: No significant differences were seen between conditions for the creep tests. The suture configuration used was determined to have a significant effect on the maximum load to failure of the constructs (p = 0.018) and maximum stress in the construct during the load to failure test (p = 0.019). Double Tape had a significantly greater load to failure than the Single Round (66N (0.021, [25, 107]) and Single Tape (72N (0.037, [18, 126]) conditions, and reached greater stresses before failure (0.1N/mm^2 (0.04, [0.03, 0.17] and 0.1N/mm^2 (0.04, [0.02, 0.18], respectively). No significant differences were found between the double tape and double round techniques, nor the Double Round and either of the Single techniques for any of the load to failure variables. Conclusion: Currently, there is no compelling data to support surgical over non-surgical management of Achilles tendon ruptures. However, by patient or surgeon preference, many patients undergo operative intervention, and percutaneous repair through a guide is a popular modality. The results of this study, using a porcine model to simulate a minimally invasive technique for Achilles tendon repairs, suggest that the use of a double locked tape suture configuration leads to a stronger overall construct. The clinical implications of these findings will be the subject of future work.