To report the experience for the precision osteoid osteoma resection using computer navigation system.

Between January 2008 and December 2009, 26 surgical resections were performed for 26 patients who had osteoid osteoma with computer navigation system. There were 23 males and 3 females with an average age of 18 years (7 to 35). Tumors were located at femoral shaft 9, femoral trochanter 4, femoral neck 2, tibial shaft 5, metaphysic of proximal tibia 1, acetabulum 2, pubis 1, vertebral appendix 1 and radial shaft 1. Pre-operative X-ray and CT of each patient was performed to confirm the diagnosis. It was carried out intraoperatively the process of CT-based navigation in 4 cases and intraoperative Iso-C three-dimensional navigation in 22 cases. The Navigation System software was Spine Navigation 1.2 in all cases. The Pointer was helpful to localize the lesion and precisely resected the lesion without removal of any excess bone.

All the navigation operations were finished successfully with curettage for 12 and En Bloc resection for 14. Bone grafting was made in 21 cases and none in 3 cases. The completely clearance of nidus by intraoperative visual inspection and Pointer confirmation, postoperative X-ray and (or) CT scan was performed in all cases. All cases had histopathology diagnosis of osteoid osteoma and immediate pain relief after surgery. All cases were followed up for 20.6 months averagely (12 to 35 months). No local recurrence and pain relapse occurred.

The navigation system is very helpful for the precision tumor resection of nidus. Especially for the patients with osteoid osteoma located at diaphysis, Intraoperative Iso-C three-dimensional navigation is more useful.