Symptomatic Os Infranaviculare
A healthy 45-year-old man was referred to our clinic with an atraumatic 3-year history of pain on the dorsomedial surface of the right foot, which worsened with activity. The pain began as a diffuse dull pain during running, and progressed to an exquisite pain during standing or after a 10-minute walk since 6 months before our clinic visit.\nTenderness was noted around the symptomatic medial midtarsal area. However, no other specific finding was found during a physical examination. His laboratory data, including his uric acid level, were also within the normal range. Radiographs of the right foot revealed a 10 × 15 mm sized accessory bone between the navicular and the medial cuneiform (), but no equivalent in the left foot. Computed tomography (CT) demonstrated that the accessory bone contacted the intermediate cuneiform and the navicular and medial cuneiform; sclerotic change and a bony spur were observed between the accessory bone and the navicular ().\nHis symptom had not improved despite the 6 months of conservative treatment for pain control, and finally, the accessory bone was excised. Intraoperatively, the tibialis anterior was not attached to the accessory bone, which articulated with the medial cuneiform and the intermediate cuneiform. However, it was connected to the navicular by synfibrosis (). At his 12-month follow-up, the patient reported pain relief during walking, but slight tenderness persisted on the surgical scar.