Exostoses occur in bones that have developed from cartilage, most often in the long tubular bones. Exostoses are rarely on the proximal phalanx. The patient reported here is a 44-year-old female who had a solitary exostosis. She noticed it's swelling but felt no pain and no sensory disturbance, so she neglected having it attended to for a long time. We resected the exostosis on the right ring proximal phalanx. As we could not pathologically find the cartilage cap, we thought it was an old exostosis.
