Fracture of the sesamoid bones of the thumb associated with volar plate injury: ultrasound diagnosis.

The fractures of sesamoid bones of the hand are rare, sometimes the diagnosis is missed. We report a case of fracture of both the ulnar and radial sesamoids of the metacarpophalangeal (MCP) joint of the thumb. The trauma (hyperextension of the thumb during a soccer match) also caused a lesion of the volar plate. The diagnosis was made by ultrasound (US) and confirmed by CT scan.