Comparison of Four Methods for Percutaneous Achilles Tendon Lengthening: A Cadaveric Study.

Percutaneous Achilles tendon lengthening can result in Achilles tendon rupture. This complication has been controversially linked to torsion effects in the Achilles tendon. Routine percutaneous triple-hemisection techniques (group A), rotary triple-hemisection (group B), distal double-hemisection (group C), and proximal double-hemisection (group D) were compared in cadaveric specimens to provide insights into the mechanism of uneven incision lengthening and inadvertent Achilles tendon rupture. The degree of Achilles tendon torsion on various planes was measured in 20 lower limb pairs from fresh cadavers. The increase in postoperative maximum ankle joint dorsiflexion degree and the length of the lengthened Achilles tendon were greater in group B (p < .05) and group C (p < .05) compared with the routine percutaneous triple-hemisection technique (group A). The width of the tensile gap of the distal incision was significantly greater in group B (p < .05) and group C (p < .05) compared with that in group A. Rotary triple-hemisection was shown to eliminate the effect of Achilles tendon torsion on percutaneous Achilles tendon lengthening. Because proximal double-hemisection is performed away from the distal Achilles tendon where the fibers rotate sharply, the technique results in more even extension of the incisions and achieves a greater increase in the maximum degree of ankle joint dorsiflexion. Uneven incision lengthening was observed with the routine percutaneous triple-hemisection and distal double-hemisection techniques. Achilles tendon torsion affected the surgical outcomes. Rotary triple-hemisection and proximal double-hemisection techniques resulted in more even extension of the incisions and achieved a greater increase in the degree of maximum ankle joint dorsiflexion.