An exquisitely painful fingertip lesion

A woman in her 50s presented with a five year history of a painful, slightly raised erythematous lesion under the distal aspect of her right fifth finger nail plate and fingertip region that very slowly increased in size (fig 1). Her only other symptom was sensitivity in cold weather. She had a history of hypertension, but no history of trauma or any notable family history. The woman had previously seen her general practitioner and was told that the lesion was likely benign, possibly a viral wart. She had not undergone any prior treatment. She had ongoing pain and wanted to have the lesion removed, therefore was referred to plastic surgery. On examination, the lesion measured 6 mm in size, was soft, and very tender to palpation. No associated nail plate dystrophy was present. A plain film radiograph was performed that showed evidence of bony erosion of the distal phalanx tuft (fig 2).