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[Percutaneous CT-guided radiofrequency ablation in spinal osteoid osteoma treatment].

PURPOSE OF THE STUDY
Radiofrequency ablation is a minimally invasive method indicated in the treatment of bone tumors. Its effectiveness and safety have been reported in a number of studies concerned with the therapy of osteoid osteoma of extremities. However, only scarce information is available on effectiveness of ablation in osteoid osteoma of the spine. The aim of the study was to verify the efficacy of percutaneous CT-guided radiofrequency ablation on this indication.


MATERIAL AND METHODS
This prospective study included four patients, three women and one man, with osteoid osteoma of the lumbar or sacral spine who were treated by percutaneous CT-guided radiofrequency ablation in the period from February 2002 to March 2005. Two tumors were found in the third lumbar vertebra, one in the fourth lumbar and one in the first sacral verstebra. The pre-operative pain values assessed on the visual analogue scale (VAS), and function restriction rated by the Oswestry Disability Index (ODI) were compared with the post-operative values at 2 years after surgery. Patients' satisfaction with surgical outcome was evaluated according to Odom's criteria.


RESULTS
All four procedures were accomplished successfully in technical terms and the patients completed the two-year followup. All patients reported significant relief of pain immediately after surgery and this held even after 2 years. The average pre-operative VAS value of 8.3 was reduced to 2.45 at the final examination, and the pre-operative ODI of 70/100 improved to 95/100 post-operatively. The outcome of treatment rated by Odom's criteria was regarded as excellent.


CONCLUSIONS
Percutaneous CT-guided radiofrequency ablation is an effective and safe method for treatment of spinal osteoid osteoma. It has advantages that could make it preferable to surgical excision of tumors. Key words: osteoid osteoma, computed tomography, radiofrequency ablation.