Introduction: Osteoid osteoma is a benign tumour that usually requires surgical excision as it commonly presents with severe and debilitating pain. Treatment by percutaneous drill resection with CTscan control was developed by Doyle, Voto & Kohler 15 years ago as an alternative to the classical “en bloc resection”. A series of 62 cases using this method is reported.

Method: The procedure is performed by an orthopaedic surgeon in the CT Scan room with the radiologist participation. The lesion (nidus) is localized on an appropriate CT slice. A special set of instruments (drill, trephine, reamer) are introduced in succession along a guide wire through a short skin incision. A small cylinder of bone is removed for histopathology analysis.

Between June 1987 and July 2003, 62 cases were so far treated. There were 13 adults (19 – 35 years) and 49 children and adolescents (2.5 years – 18 years). All patients had a clinical and radiological evidence for osteoid osteoma (hyperfixation on scintigraphy, visible nidus on CT scan). The nidus was mostly localized in the lower limb (53 cases) especially femoral neck (23), femoral shaft (13), tibial shaft (14).

Results: No severe complications were observed (delayed union after skin necrosis of the tibia in 3 cases, transitory palsy of extensor hallucis longus in one case. Clinical healing after a 1 year follow up was observed in all but 2 cases. In these 2 cases the lack of healing was considered as a failure of treatment and not true “recurrence”; a second attempt was successful. The nidus was confirmed in the specimen in half cases.

Discussion: This method has now clearly demonstrated its effectiveness and security. Benefits for patients are evident: thanks to minimal bone resection, quick recovery and immediate weight bearing are possible. This technique is now indicated in most cases, versus “en bloc resection” which should be considered only for some vertebral or superficial localizations of the nidus. Concurrently, other techniques have been recently developed : destruction by thermo coagulation or photocoagulation, which are similar to resection ; all are non invasive interventional procedure.