Osteoid osteoma and osteoblastoma of the sacrum.

This retrospective study examined 10 patients with osteoid osteoma and 11 patients with osteoblastoma localized in the sacrococcyx. In the sacrum, the diagnosis was delayed compared to other sites. Curettage through a posterior approach is the treatment of choice. Radiotherapy as well as embolization of feeding arteries may be used for the most aggressive lesions. Prognosis is generally good with a low incidence of local recurrence (<10%).