A rare cause of leg pain

Sclerosing bone dysplasias (SBD) are skeletal abnormalities characterised by an increase in segmental or generalized bone mass. In this case report, a 76-year-old woman presented right leg pain. The radiological examination revealed a fusiform enlargement of the right femur with marked cortical thickening and narrowing of the medullary canal. A subsequent bone scan reported an intense uptake of radionuclide localised in the same anatomical site. Routine biochemical tests were in the normal range. On suspicion of osteosarcoma, the patient underwent a biopsy of the bone lesion that showed no neoplastic proliferation. In light of the medical history, laboratory tests and instrumental examinations, the patient was diagnosed with Ribbing disease. She was treated with a low dose of prednisone 5 mg/day and experienced a reduction of pain.