Osteoid osteoma and Osteoblastoma

The osteoid osteoma and osteoblastoma are histologically identical and distinguished by osteoblastoma being bigger (greater than 2 cm). They are benign conditions that unfortunately are poorly tolerated as they cause a lot of pain. They uniquely become painless after treatment with non-steroidal anti-inflammatory drugs which unfortunately cannot be given long-term due to their side -effects. Treatment involves curettage and cementation and prognosis is excellent.

Figure. This 8 year-old boy had a right proximal humerus osteoblastoma. It was mistaken for an osteosarcoma and had been planned for chemotherapy. We were consulted and gave a second opinion of an osteoblastoma. This was curretted and cemented and the patient has since grown to adulthood without incident.