Multiple lower limb non-ossifying fibromas in siblings with neurofibromatosis.

Non-ossifying fibromas are common benign lesions of tubular long bones. There is recognized association of these bony lesions with neurofibromatosis type 1 although the presence of non-ossifying fibromas in familial members with the condition has not previously been reported. We report two siblings with neurofibromatosis and radiological evidence of multiple lower limb non-ossifying fibromas. Both patients presented with pain in the knees and a pathological fracture was observed in one case. Patients with multiple non-ossifying fibromas should be examined carefully for other evidence of neurofibromatosis.