Centripetal fat deposition is a well-recognized consequence of excessive use of corticosteroids, either endogenous or exogenous. Recently, several patients receiving large doses of corticosteroids have suffered compressive myelopathies due to excessive epidural fat collections, labeled "epidural lipomatosis." Two of these have been children, and a third child is reported here. This child was receiving chronic steroids for juvenile rheumatoid arthritis when he presented with such a myelopathy, which was confirmed by metrizamide computerized tomography myelography as well as by surgical exploration. Histological examination revealed that the epidural tissue was a brown-fat tumor or "hibernoma." An epidural hibernoma has not been described previously. The histological and endocrine features of fat in Cushing's syndrome are discussed, and the literature concerning hibernoma and epidural lipomatosis is reviewed.