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Updated: Jun 27, 2026

Automated Joint Space Detection Improves Bone Segmentation Accuracy
Published on: November 28, 2025
Coexistence of Tripartite Accessory Navicular Bone and Os Subfibulare
George Triantafyllou1, Nikolaos-Achilleas Arkoudis2,3, Christos Koutserimpas4
1Department of Anatomy, School of Medicine, Faculty of Health Sciences, National and Kapodistrian University of Athens, 11527 Athens, Greece.
Abstract:
This report describes a unique constellation of accessory ossicles, highlighting their anatomical, clinical, and radiological significance. A 43-year-old female undergoing imaging for suspected fracture was evaluated using multi-detector computed tomography (MDCT) with 1.25 mm slice thickness. Multiplanar reconstructions (axial, coronal, sagittal) and three-dimensional volume-rendered images were analyzed. CT imaging revealed the coexistence of an os subfibulare and a tripartite os naviculare. Multiplanar and three-dimensional reconstructions confirmed the presence and configuration of variants. The combination of supernumerary bones and a multipartite ossicle represents an exceedingly uncommon anatomical presentation. This case illustrates an exceptional coexistence of multiple accessory ossicles, including an exceedingly rare tripartite os naviculare. Thorough radiological evaluation using MDCT and multiplanar reconstructions is essential for accurate identification and differentiation from fractures or other pathology.
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