Treatment of Huge Intraosseous Lipoma of Distal Femur with Genu Valgum: A Case Report

Intraosseous lipomas are rare benign primary tumors of the bone. The intraosseous lipoma may be asymptomatic, and then the lesion may be found incidentally during radiological investigation following an injury in the same region. Intraosseous lipoma is frequently confused histologically or radiologically with fibrous dysplasia, enchondroma, osteoblastoma, chondrosarcoma, bone cyst, and bone infarct. We report a 64-year-old woman suffered from exacerbation of climbing-stairs pain in her right knee due to a juxta-articular bone tumor in distal femur. The symptoms improved after excisional curettage of the tumor and then reconstructed with constrained condylar knee replacement. Histopathological examination of the tumor confirmed the diagnosis of intraosseous lipoma. Although intraosseous lipomas are considered benign lesions and are treated conservatively due to their propensity for spontaneous involution, curettage and grafting has been suggested in cases with painful tumors, pathological fractures or other secondary changes. Curettage and bone grafting is an option for treatment with a good clinical and functional result. And intraosseous lipoma should be considered in the differential diagnosis of osteoblastic lesions for the orthopedic surgeon.