Intraosseous hibernoma mimicking sclerotic bone metastasis—a case report

Intraosseous hibernoma is an uncommon presentation of brown adipose tissue benign tumors. Imaging differential diagnoses include bone island, sclerotic metastasis, lymphoma, hemangioma, and sclerotic myeloma. In this report, a 72-year-old patient presented with right hip pain following a fall injury, leading to an extensive diagnostic workup. Initial CT of the pelvis without contrast suggested potential sclerotic metastatic disease. MRI findings could not be definitive. Further assessment with CT-guided biopsy and S-100 immunohistochemical staining confirmed a rare diagnosis of intraosseous hibernoma. This case describes multimodality imaging characteristics of a rare intraosseous hibernoma with discussion of imaging features of differential diagnostic considerations of related benign and malignant bone lesions.