Extensor Retinaculum Reconstruction Using a Tensor Fasciae Latae Graft for Bowstringing of the Tibialis Anterior Tendon: A Case Report

Bowstringing of the tibialis anterior (TA) tendon is an extremely rare condition caused by closed disruption of the extensor retinaculum, and no standard treatment strategy has been established. We report a post-traumatic case of symptomatic TA tendon bowstringing successfully treated with extensor retinaculum reconstruction using an autologous tensor fasciae latae (TFL) graft. A 44-year-old patient sustained a crush injury when his left lower extremity was run over by a forklift and underwent surgical fixation for a medial malleolar fracture and stabilization for a distal tibiofibular syndesmotic injury. After initiation of postoperative rehabilitation, he developed persistent anterior ankle pain and visible bowstringing of the TA tendon during dorsiflexion, and conservative treatment failed to relieve his symptoms. Clinical examination revealed limited ankle dorsiflexion and tenderness along the TA tendon. Magnetic resonance imaging and dorsiflexion-position computed tomography confirmed anterior displacement of the TA tendon due to complete closed disruption of the extensor retinaculum. Surgical reconstruction was performed using an autologous TFL graft passed subcutaneously between the medial and lateral malleoli and fixed with suture anchors under maximum dorsiflexion. At the 1-year follow-up, pain had completely resolved, and ankle dorsiflexion improved from −5° to 10°. The Japanese Society for Surgery of the Foot ankle/hindfoot score improved from 62 to 97, and patient-reported outcomes assessed using the Self-Administered Foot Evaluation Questionnaire demonstrated marked improvement across all domains. This case suggests that extensor retinaculum reconstruction using a TFL graft is an effective surgical option for symptomatic TA tendon bowstringing caused by closed extensor retinaculum injury.