Fig. 1

A 20–30 year old patient with right femoral osteoid osteoma treated with radiofrequency ablation guided by three-dimensional (3D) image-guided (O-arm) technology. a The Optical tracking frame is fixed to the femur and then calibrated to the navigation system. b A navigated Jamshidi needle is introduced to the bone and penetrating the lesion with real time navigation. c A Radiofrequency probe needle is inserted into the lesion, followed by ablation according to a protocol of 90 °C for 6–9 min