Does Suture Configuration Matter in Achilles Tendon Repairs?

The human Achilles tendon is functionally important for dynamic activities and is a common site of tendon rupture, 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 common suture configurations in the repair of Achilles tendon ruptures.

This biomechanical study utilized porcine toe flexor tendons as an analogue for the human Achilles tendon.

Simulated rupture was performed, and tendons were repaired using a percutaneous guide. The technique was uniform with predetermined 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. Specimens then underwent a static creep test, a dynamic load creep test, and finally a load-to-failure test. An analysis of variance was performed to test for differences between the variables, followed by pairwise comparisons using independent t-tests to assess inter-group differences if significant effects were found, adjusted for multiple comparisons.

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 and single conditions and reached greater stresses before failure (respectively). No significant differences were found between the double tape and double round techniques, nor between the double round and either of the single techniques for any of the load-to-failure variables.

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.