Preoperative Assessment Using Magnetic Resonance Imaging for Subungual Exostosis beneath the Proximal Region of the Nail Plate.

Subungual exostosis is a benign calcifying projection that occurs on the distal phalanx beneath or beside the nail. The problems in treatment are frequent postoperative recurrence and nail deformity or loss. Here, we describe the case of a male patient with a subungual exostosis beneath the proximal region of the nail plate of the right big toe. A precise preoperative evaluation of the anatomical structure using magnetic resonance imaging was useful for removing the subungual exostosis.