Osteoblastoma

General characteristics

Osteoblastoma is a rare benign tumor. It is at least four times less common than osteoid osteoma.

Epidemiology

There is a male predominance, with a male-to-female ratio of 2.5:l. Its peak incidence is in the second decade, and it is rare before 10 years of age and after 30 years of age.

Location

Its most common location is the spine, usually in the posterior elements. In the long bones, it is most often located in the metadiaphyseal region; in rare circumstances, it can extend into the epiphyses in the adult.

Imaging

On CT scans, an osteoblastoma appears as an expansile lytic lesion, often with a mineralized matrix, surrounded by a thin bony shell. Dense sclerosis and periosteal reaction may occasionally be present. An osteoblastoma typically has low to intermediate signal intensity on TI-weighted MR images and high signal intensity on T2-weighted images. Edema in the surrounding soft tissues and in the bone marrow beyond the tumor margins is comtn