Bipartite talus is a rare anatomical variation characterized by the division of the talus into 2 distinct fragments by a cartilaginous or fibrocartilaginous interface. Clinically, bipartite talus primarily manifests as posterior ankle pain accompanied by joint stiffness and start-up pain, necessitating differentiation from the posterior talus triangle. Currently, reported cases of bipartite talus are scarce, particularly among elderly patients, and treatment protocols remain scarcely reported. A 60-year-old female patient presented with persistent pain and limited mobility in the posterior aspect of her left ankle over the past 2 years, with symptoms significantly worsening 1 year prior. She presented no history of trauma or infection. Physical examination revealed mild posterior swelling, tenderness in the posterolateral region, and pain on initiation of movement. There was mild limitation of plantar flexion in the left ankle joint. Imaging examinations including x-ray, computed tomography and magnetic resonance imaging demonstrated a fairly large bone fragment. Bipartite talus (left side). Perform arthroscopic surgery on the patient. The patient's pain and joint mobility limitations showed significant improvement. Arthroscopic technology can be used as an effective means of treating traumatic bipartite talus with minimal trauma and rapid recovery. However, its long-term efficacy needs to be verified by a larger sample size and longer follow-up.

Talus bipartitus is a rare skeletal anomaly that may be mistaken for an os trigonum, a relatively common accessory ossicle found posterior to the talus. Both are believed to be formed similarly with the failed fusion of the talus with a second ossification center. Os trigonum is often diagnosed incidentally or found on radiographs obtained in symptomatic patients with signs of os trigonum syndrome, which presents with posterolateral ankle pain. A bipartite talus may also present with similar symptoms but may be differentiated through its articular involvement. In this article, we describe the rare presentation of tarsal tunnel syndrome in a patient caused by a bipartite talus. The patient underwent surgical decompression with the removal of the posterior fragment. A bipartite talus is a rare entity that may be mistaken for an os trigonum, a common accessory ossicle. In this article, we describe an outcome of a bipartite talus fragment removal due to tarsal tunnel syndrome and illustrate a rare pathological consequence of a bipartite talus. We further highlight the importance of early surgical management in patients presenting with an identifiable structure contributing to tibial nerve compression.