Surgical and Functional Outcome of Management of Chronic Achilles Tendon Rupture with Flexor Hallucis Longus Graft: A Case Series
Authors: Jadawala Vivek , Taywade Shounak , Salwan Ankur , Pisulkar Gajanan , Saoji Amit 
Published: December 2023

Abstract
One of the most prevalent tendon injuries, especially among athletes, is Achilles tendon rupture (ATR). Chronic ATR with substantial gaps, on the other hand, still has no conventional treatment. There are a number of operative methods available, including V-Y advancement and Bosworth turn-down correction. Peroneus brevis, flexor digitorum longus, and flexor hallucis longus (FHL) tendon transfers are used in other surgical approaches. Fascia plasty or tendon transfers can also be used to treat chronic ATRs. It has been suggested to transfer and graft FHL because it is a stronger plantar flexor, its axis of contractile force more closely resembles that of the Achilles tendon, it fires in phase with the gastrocnemius-soleus complex, and its anatomic proximity to the neurovascular bundle prevents iatrogenic injuries of the bundle. Plantar flexion strength reinforcement, which is usually always compromised with fascial advancement alone, is another advantage of FHL transfer. In this case series, five patients of chronic tendo-Achilles tears who met the inclusion criteria and operated with tendon transfer from FHL from July 2020 to August 2021 were included in the study. The inclusion criteria for study participation were chronic ATR. A rupture with a diagnostic lag of more than 4 weeks, a recurrence, and ruptures with a substantial loss or degradation of tendon tissue were all considered chronic ATRs. Before surgery, every patient reported having very limited mobility. The surgery consisted of an open FHL tendon transfer to the calcaneus. Postoperatively below knee cast was applied for 6 weeks in 30° plantar flexion. All patients had their ankle-hind foot scores completed by the American Orthopaedic Foot and Ankle Society (AOFAS) at their last visit. Ankle range of motion and calf circumference were measured and contrasted with the contralateral side. After 6–8 weeks, patients were asked to resume their prior activities. The values for the damaged leg were compared to the values for the unaffected limb and are displayed as a ratio of the healthy leg for the purpose of evaluating the functional tests. Acute rupture of the Achilles tendon may not get diagnosed in as many as 25% of patients, resulting in chronic or neglected cases that become difficult to treat. The most important finding of this study is that the outcomes of acute ATR with the FHL tendon transfer technique are favorable. In our study, no patient had any complications regarding wound infection or healing which shows the efficacy of this surgical technique in the prevention of wound-related complications. Open surgical (TA) Tendoachilles repair is preferred because it facilitates an early resume to activity and has a higher rate of early return to their normal physical activity routines. With surgical repair, chances of retear are lesser and ideal, long-term results are obtained. The present case series study showed that FHL tendon transfer has an excellent result for tendo-Achilles tendon reconstruction. FHL tendon transfer will become a gold standard method for chronic TA repair in future.