Bilateral Naviculocuneiform Coalition in a Pediatric Patient: A Common Pathology in a Rare Location

Tarsal coalition is a condition characterized by abnormal fusion of two or more bones in the hindfoot or midfoot, typically presenting in adolescence with pain, stiffness, or recurrent sprains. While the most common types are calcaneonavicular and talocalcaneal coalitions, naviculocuneiform coalitions are exceedingly rare and often underdiagnosed due to subtle or absent radiographic findings. We report the case of an 11-year-old previously healthy female who presented with left midfoot pain following minor trauma. Physical examination revealed focal tenderness at the medial and dorsal aspects of the midfoot, with preserved range of motion. Initial radiographs showed no acute fractures or dislocation, but marginal spurring at the medial naviculocuneiform joint, an atypical finding in pediatric patients, was noted. Given these imaging findings, an MRI of the foot was obtained and demonstrated cortical irregularity with surrounding edema at the naviculocuneiform joint without marrow continuity, consistent with a non-osseous (likely cartilaginous or fibrous) coalition. Retrospective evaluation of prior contralateral foot radiographs revealed similar findings, supporting a diagnosis of bilateral naviculocuneiform coalition. The patient was referred to podiatry and is currently undergoing conservative management with activity modification and immobilization. Naviculocuneiform coalition is an exceptionally rare variant of tarsal coalition, with minimal documentation in the literature. Epidemiologic studies suggest a much lower incidence compared to more common coalition types, and some populations may exhibit geographic or ethnic predispositions. The presentation is often non-specific, and non-osseous coalitions in particular may evade detection on plain radiographs. MRI plays a crucial role in identifying such coalitions when clinical suspicion is high and initial imaging is inconclusive. Recognition of rare coalition types is important in the differential diagnosis of pediatric midfoot pain to prevent misdiagnosis and guide appropriate management. First-line treatment remains conservative, reserving surgical intervention for refractory or functionally limiting cases. This case highlights a rare presentation of bilateral naviculocuneiform coalition in a pediatric patient, precipitated by minor trauma. It underscores the importance of advanced imaging in evaluating unexplained midfoot pain in young patients and expands the growing body of literature on rare tarsal coalitions. Clinical awareness of such atypical presentations is essential for timely diagnosis and management.