Achilles tendon revision: when, how, and why?

The Achilles tendon is the primary plantar flexor of the foot and the strongest tendon in the human body. It is important to make an early and accurate diagnosis of Achilles tendon injuries through clinical and instrumental evaluations to establish preoperative planning because Achilles tendon injuries are misdiagnosed up to 25% of the cases and if left untreated for more than four weeks, the injury is considered chronic. Achilles tendon ruptures occur more frequently in males than females and both neglected Achilles tendon injuries and re-ruptures result in anatomical alterations that make revisions challenging. Chronic Achilles tendon injuries are expected to rise due to the increasing incidence of Achilles tendon ruptures and the use of conservative treatments. Chronic injuries are associated with higher healthcare costs compared to early diagnosis and treatment and lead to significant functional disability. There is no consensus in the literature regarding treatment-per-defect size. However, based on previous research, the authors suggest an algorithm that considers 5- and 10-cm defects as thresholds modifying treatment strategies. If tendon stump approximation is possible, different sutures are feasible for end-to-end anastomosis. The Krackow suture is the most effective option compared to Bunnell, Kessler, and modified Kessler. FiberWire outperforms Prolene and Ticron. For gastrocnemius soleus complex elongation, the Baumann, Strayer, Baker, Helander, the Y-V, and Vulpius techniques can be used. For fascial turndowns, the Christensen, Boseworth, and modified Boseworth with mesh augments are suitable. Autografts can be derived from hamstring tendons through semitendinosus autografts or local or regional free flaps such as the fascia lata flap. Allografts can come from various sources, such as hamstrings or Achilles tendons, with or without bone blocks. Various tendons can be used as transfers, including peroneus brevis, peroneus longus, flexor hallucis longus, flexor digitorum longus, and plantaris longus. When: chronic Achilles tendon injury and re-rupture cases are on the rise despite the decreased frequency of surgical treatments. The cost of surgical treatment for chronic and re-ruptured Achilles tendon injuries outweighs those of early diagnosis and prompt surgical treatment for acute Achilles tendon injuries. How: the revisional surgery of neglected Achilles tendon injuries and re-ruptures is challenging, and the surgical approach depends on the extent of tissue defect. Revisional surgery can be performed using end-to-end anastomosis, gastrocnemius and soleus elongation, fascial turndown, tendon transfer, and utilizing autograft and allograft. Why: the authors stress the importance of accurate diagnosis and early surgical intervention to reduce comical burden and prevent the growing prevalence of neglected and re-ruptured Achilles tendon injuries. Even if treatment is delayed, patients should receive appropriate Achilles tendon revisional surgery to ensure better functional outcomes and a higher quality of life.