Non-ossifying Fibroma Pathological Fracture in a Patient With Lactose Intolerance.

Non-ossifying fibroma (NOF) is a frequently occurring benign tumor of children and adolescents. In the long bones, it appears as an eccentric, expanded lesion in the metaphyseal diaphyseal area. Most cases are asymptomatic and resolve at a later age while others might become symptomatic and have a high risk of fracture. We present a case of a 15-year-old boy who is known to have lactose intolerance, suffered a pathological fracture following trauma, and was diagnosed with non-ossifying fibroma of the proximal tibia. The etiology of these lesions is not well-known. However, there might be a relation between tendons and NOF. This reported case of NOF is in the proximal tibia, which is a common site of the lesion beside the distal femur. Our reported case was treated by open curettage and grafting, which is the recommended classical treatment. On follow-up, full union was achieved without complications.