An Innovative Idea of Tendon Transfer Using a Gracilis Muscle Tendon for a Posterior Tibial Tendon Rupture: A Case Report

Abstract A 42-year-old man, who is the first author of this article, presented with pain and left ankle swelling during a 100-km running race. He experienced a sharp pain and popping sensation while running upstairs 15 days after the race. He had previously received a steroid injection around the medial malleolus. Foot inversion was impossible; left toe gait was difficult. Magnetic resonance imaging revealed posterior tibial tendon discontinuity. Although the tendon was found to be discontinued 2-cm proximally to the medial malleolus on surgery for reconstruction, the history of steroid injection could also be responsible for the degeneration of the cut ends. Because of the degeneration, the debrided cut ends showed a gap that could not be directly sutured. Some researchers have reported good tendon transfer results using the flexor digitorum longus, which is situated along the posterior tibial tendon below the medial malleolus. However, loss of function of the flexor digitorum longus can cause a loss of the toe grip power, resulting in an inability to run. Therefore, we adopted the gracilis muscle tendon for tendon transfer. The degenerated cut ends were debrided and reconstructed using a gracilis muscle tendon of the same side. Active range-of-motion exercises were initiated after 3 weeks of below-knee casting. Jogging was permitted at 12 weeks after surgery. He completed a 100-km run at 11 months after surgery. Following one-and-half year, the function was restored. The case warrants publication because this novel tendon transfer technique has not been reported and was effective for a runner.