This report discusses an unusual case of a 23-year-old woman with a painful bipartite medial cuneiform and severe arthritic and cystic changes at the partition with no history of trauma. Magnetic resonance imaging confirmed a large cyst with subchondral erosions at the dorsal and plantar segments with significant bone marrow edema. Definitive treatment consisted of arthrodesis on the dorsal to plantar segments using one lag screw, demineralized bone matrix grafting, and a bone stimulator.