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Tarsal Tunnel Syndrome Associated With a Bipartite Talus
1From the Renaissance School of Medicine, Stony Brook University, Stony Brook, NY (Torres), and the Department of Orthopaedic Surgery, Stony Brook School of Medicine, Stony Brook, NY (Dr. Paulus).
Background:
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.
Case:
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.
Conclusion:
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.
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