Osteoid osteoma of third metatarsal bone treated with radiofrequency ablation: Case report, imaging findings and review of the literature.

Osteoid Osteoma (OO) is a frequent benign bone tumor that commonly affects males between 5 and 25. It usually arises from appendicular skeleton involving typically femur and tibia. OOs arising from small bones of hands and feet are very uncommon and metatarsal lesions account for only 1.7%. We report a case of a 20 year-old boy with a long history of nocturnal left foot pain with a good clinical response to assumption of salicylates or nonsteroidal anti-inflammatory drugs (NSAIDs). Plain radiograph of his left showed unconclusive results. Therefore, he underwent a contrast enhanced CT (CECT) scan with multiplanar reconstruction (MPR) that showed a bony lesion in the left third metatarsal bone that was compatible with a nidus even in absence of clear peri-nidal sclerosis. Therefore, other ancillary techniques such as MRI and bone scintigraphy were performed. Conclusive diagnosis was OO of third left metatarsal bone. Our patient underwent a mini-invasive treatment with radiofrequency (RF) ablation. After recovery, our patient had no post-operative complications and showed optimal clinical conditions with complete remission of left foot pain and no change or impairment in walking. In this essay, we discuss key imaging findings of OO of small bones and its treatment with radiofrequency ablation. We describe method of execution and illustrate advantages of this mini-invasive technique. We also perform a review of the literature.