Computed tomography-guided radiofrequency ablation of intra-articular osteoid osteoma: a single centre's experience.

OBJECTIVE: To evaluate safety and efficacy of radiofrequency ablation (RFA) in the treatment of painful intra-articular osteoid osteoma. MATERIALS AND METHODS: During the last 3 years, 15 patients underwent computed tomography (CT)-guided biopsy and RFA of symptomatic intra-articular osteoid osteoma. In order to assess and sample the nidus, a coaxial bone biopsy system was used. Biopsy was performed and followed by ablation session with osteoid osteoma protocol in all cases. Procedure time (i.e. drilling including local anaesthesia and ablation), amount of scans, the results of biopsy and pain reduction during follow-up period are reported. RESULTS: Access to the nidus through normal bone, biopsy and electrode insertion was technically feasible in all cases. Median procedure time was 54 min. Histologic verification of osteoid osteoma was performed in all cases. Median amount CT scans, performed to control correct positioning of the drill and precise electrode placement within the nidus was 9. There were no complications or material failure reported in our study. There was no need for protective techniques of the articular cartilage. Pain reduction was significant from the first morning post ablation and complete at the one week and during the follow-up period. No recurrences were noted. CONCLUSIONS: RFA under CT guidance is a safe and efficient technique for the treatment of painful intra-articular osteoid osteoma. Imaging guidance, extra-articular access through normal bone and exact positioning of the needle-electrode inside the nidus facilitate safety of the technique and prevention of damage to the articular cartilage.

Percutaneous Biopsy and Radiofrequency Ablation of Osteoid Osteoma with Excess Reactive New Bone Formation and Cortical Thickening Using a Battery-Powered Drill for Access: A Technical Note.

PURPOSE: To report our experience with the use of a battery-powered drill in biopsy and radiofrequency ablation of osteoid osteoma with excess reactive new bone formation. The battery-powered drill enables obtaining the sample while drilling. MATERIALS AND METHODS: During the last 18 months, 14 patients suffering from painful osteoid osteoma with excess reactive new bone formation underwent CT-guided biopsy and radiofrequency ablation. In order to assess and sample the nidus of the osteoid osteoma, a battery-powered drill was used. Biopsy was performed in all cases. Then, coaxially, a radiofrequency electrode was inserted and ablation was performed with osteoid osteoma protocol. Procedure time (i.e., drilling including local anesthesia), amount of scans, technical and clinical success, and the results of biopsy are reported. RESULTS: Access to the nidus through the excess reactive new bone formation was feasible in all cases. Median procedure time was 50.5 min. Histologic verification of osteoid osteoma was performed in all cases. Radiofrequency electrode was coaxially inserted within the nidus and ablation was successfully performed in all lesions. Median amount CT scans, performed to control correct positioning of the drill and precise electrode placement within the nidus was 11. There were no complications or material failure reported in our study. CONCLUSIONS: The use of battery-powered drill facilitates access to the osteoid osteoma nidus in cases where excess reactive new bone formation is present. Biopsy needle can be used for channel creation during the access offering at the same time the possibility to extract bone samples.