We present a case of a 13 year old girl with swelling and pain of the right lower leg persisting for four months. The radiological and histological diagnosis is osteofibrous dysplasia. Osteofibrous dysplasia is a rare bone lesion predominantly affecting the cortex of the tibia. Almost all patients are younger than ten years at presentation. Swelling is a typical clinical manifestation. Radiologically and even histologically the distinction between the osteofibrous dysplasia and the more aggressive adamantinoma can be difficult. Other bone lesions potentially mimicking osteofibrous dysplasia include: fibrous dysplasia, osteoid osteoma, osteosarcoma, osteoblastoma and intracortical Brodie's abcess. The natural course of the disease is unpredictable. Lesions with typical radiological appearance are considered to be "no touch lesions". In equivocal cases block resection (with both a diagnostic and therapeutic purpose) should be performed.