A case of an aneurysmal bone cyst of a metatarsal: review of the differential diagnosis and treatment options.

UNLABELLED: Aneurysmal bone cyst localized to the metatarsus, while not unheard of, is rather uncommon. The differential diagnosis for this lesion can be challenging, particularly in regard to the possibility of the presence of other giant cells containing tumors of bone, such as giant cell tumor, giant cell reparative granuloma, Brown's tumor of hyperparathyroidism, and telangiectatic osteosarcoma. We report a case of an aneurysmal bone cyst localized to the third metatarsal in a 14-year-old girl who presented with limping, progressively worsening local pain, and swelling in her left foot. The differential diagnosis for her condition was extensive. Ultimately, an en bloc resection was undertaken and the defect was replaced with tricortical iliac autograft. Pathological analysis of the resected tissue was consistent with aneurysmal bone cyst. There was complete healing with no sign of recurrence 3 years after the surgery. LEVEL OF CLINICAL EVIDENCE: 4.