Fracture of the medial sesamoid bone of the hallux.

Fracture of the sesamoid bones of the hallux is rare. A case of fracture of the medial sesamoid bone is presented. The X-ray finding of an irregular line dividing the medial sesamoid bone together with typical local symptoms and signs established the diagnosis in a 17-year-old female athlete. Nonunion of the fractured sesamoid was successfully treated by extraction of the sesamoid fragments. Complete relief of pain was followed by the patients' return to full athletic activity. The diagnostic criteria and indications for operation are discussed briefly.