Intraosseous Epidermoid Inclusion Cyst Presenting as a Paronychia of the Hallux

Intraosseous epidermoid inclusion cysts are rare benign bone lesions that occur most commonly in the skull and in the distal phalanges of the fingers. Herein we report a case of an intraosseous epidermoid inclusion cyst occurring in the distal phalanx of the left hallux. Only six occurrences of this lesion have been described in the foot. This patient’s presentation, with active drainage (initially appearing as purulent discharge from an acutely tender ingrown hallux nail) and a known inoculation event accompanied by severe peripheral vascular disease, make this case unique. (J Am Podiatr Med Assoc 100(2): 133–137, 2010)