Surgical Technique Influences Rehabilitation Regimen: Letter to the Editor

Dear Editor:

I would like to thank Eliasson et al ¹ for their recently published research. Their randomized controlled trial demonstrated that the rehabilitation regimen in the initial 8 weeks following the surgical repair of a ruptured Achilles tendon did not significantly influence the measured outcomes, including tendon elongation. They found that tendon elongation and compliance continued to increase for up to 6 months after surgery and that muscle strength, muscle endurance, and patient-reported functional scores did not reach normal values at 12 months after surgery. These researchers used a Kessler suture technique and No. 1 Vicryl suture material. However, their results may be applicable only to a Kessler suture technique with bioabsorbable suture material. It is notable that the articles cited by Eliasson et al to support their findings also used bioabsorbable suture material and a nonlocking suture technique.^2,6,9

Two phases of elongation have been described in the literature. ² The first phase occurs during weeks 0 to 5 and may be due to tightening of the suture loops and/or tissue necrosis. This may be minimized with the use of a locking suture technique with small tight loops (eg, Krackow) and high-tensile material (eg, FiberWire). The second phase is weeks 5 to 60, which may be reduced by early mobilization and reduction of adhesions. However, the surgical construct must be strong enough throughout this stage to resist elongation while mobilization is being performed.

Achilles tendon healing is notoriously slow and takes on the order of 3 to 12 months to reach full strength.^4,5 Vicryl suture (Polyglactin 910) loses approximately one-third of its strength within 2 weeks and approximately two-thirds of its strength within 3 weeks. Therefore, it is unlikely that this suture material and technique will prevent elongation after the suture material has lost tensile strength, unless the tendon is held immobilized.

It is well established that controlled mobilization of healing tendons improves outcomes. ³ Animal studies showed that although loading of the healing tendon is beneficial and promotes remodeling, ⁷ excessive loading can have a detrimental effect on tendon healing. ¹⁰ The optimal timing and magnitude of loading remain uncertain and, following surgery, may depend on the surgical technique used.

Recommendations to reduce lengthening following Achilles tendon repair include the use of large nonabsorbable braided suture material, with a small-loop locking suture technique and sutures tied away from the rupture site. ⁵

The results of the randomized controlled trial performed by Porter and Shadbolt ⁸ suggested that an early active movement protocol resulted in less lengthening and a quicker return to running. These conclusions contradict those of Eliasson et al, but this is likely related to the use of high-tensile suture material and a locking Krackow technique. The result may be a surgical construct that is sufficiently strong to protect the healing tendon during the more vulnerable phases of healing. The rehabilitation protocol may have to vary according to surgical technique.