Tarsal tunnel syndrome after total ankle replacement—a report of 3 cases

© 2016 The Author(s). Published by Taylor & Francis on behalf of the Nordic Orthopedic Federation. This is an Open Access article distributed under the terms of the Creative Commons Attribution-Non-Commercial License (https://creativecommons.org/licenses/by-nc/3.0) DOI 10.3109/17453674.2015.1132186 Case 1 A 67-year-old man presented with a 3-year history of ankle pain and long duration lateral ankle instability. A plain radiograph showed 11 degrees of ankle-congruent varus deformity. For ligamentous posttraumatic osteoarthritis, we performed total ankle replacement (TAR) combined with deltoid ligament release and a modified Broström procedure. 6 months after TAR, the patient experienced numbness at the plantar surface of the forefoot and sometimes shooting pain. On physical examination, dorsiflexion-eversion test and Tinel sign were positive for the tibial nerve behind the medial malleolus. An electromyographic study showed prolonged posterior tibial nerve latency of the abductor hallucis and abductor digiti quinti muscle, consistent with tarsal tunnel syndrome. 3 months of treatment with a non-steroidal anti-inflammatory drug and physiotherapy failed. Tarsal tunnel release and neurolysis were performed 9 months after TAR. Intraoperatively, the posterior tibial nerve seemed compressed and thinned under the flexor retinaculum, whereas it was swollen and hyperemic proximal of the flexor retinaculum (Figure 1A). After tarsal tunnel release, the pain was completely relieved and the intermittent numbness partially improved over the 4 years of follow-up. Case 2 A 65-year-old woman presented with a 4-year history of ankle pain and a long history of lateral ankle instability. Her left ankle showed 14 degrees of ankle-incongruent valgus deformity. We performed a TAR combined with deltoid ligament release and a modified Broström procedure for ligamentous posttraumatic osteoarthritis. 3 months after TAR, the patient presented with paresthesia and a burning sensation on the plantar aspect of the forefoot. 3 months of nonoperative treatment failed, and a tarsal tunnel release and neurolysis were performed. Intraoperatively, there were similar findings to case 1 (Figure 1B). Her symptoms were completely relieved over the 5 years of follow-up.