Osteoblastoma in the region of the hip.

Osteoblastoma occurring in the region of the hip is very rare, and vague symptoms with uncharacteristic radiographic features often lead to misdiagnosis. Because of radiographic and histological similarities, it must be carefully distinguished from osteoid osteoma, aneurysmal bone cyst, giant cell tumor, and osteosarcoma. Computed tomography is the preferred imaging modality as it is able to detect the nidus and images will not exhibit the flare phenomenon caused by surrounding inflammation seen with magnetic resonance imaging. For hip joint lesions in weight-bearing areas, intralesional curettage may achieve satisfactory outcomes as compared with wide resection. We herein report two cases of osteoblastoma in the hip region in which diagnosis was delayed that were successfully treated with curettage and followed by high-speed burring.