Osteoid Osteoma of the Tibia

This is a 19 year old male who presented with night pain in his leg. Frontal radiograph of the tibia and fibula demonstrates focal cortical thickening of the tibia. The second radiograph demonstrates a focal lucency witin the tibia suggestive of a central nidus. Without this lucency, the differential diagnosis for focal cortical thickening of a long bone includes stress fracture, chronic osteomyelitis, or an osteoid osteoma. A central lucency is compatible with a nidus of an osteoid osteoma. Pain at night relieved by NSAIDS is the classic history seen with these patients. Treatment is often performed by radiofrequency ablation of the nidus.