Treatment of Painful Extraspinal Bone Metastases with Percutaneous Bipolar Radiofrequency Under Local Anesthesia: Feasibility and Efficacy in Twenty-Eight Cases

{Purpose: To retrospectively assess the feasibility and efficacy of bipolar radiofrequency ablation (RFA) of extraspinal osseous neoplasms performed under local anesthesia. Methods and Materials: Twenty-eight patients (21 males, 7 females; mean age, 61.2 years) underwent RFA under local anesthesia between 2005 and 2012. All included patients suffered from painful osseous metastases refractory to previous medication; all presented with end-stage neoplasms. RFA was performed under computed tomography (CT) guidance with bipolar radiofrequency probes. All procedures were performed under local anesthesia (lidocaine-ropivacaine) and nitrous oxide ventilation. Intravenous injection of paracetamol was performed throughout the procedure with or without intravenous injection of nalbuphin. Tolerance of procedure was recorded. Pain efficacy was evaluated on visual anologue scale (VAS) scores at day 7, 1 month, and at 6 months after the procedure. Results: Technical success rate was 100%. The procedure was considered not painful in 4 cases and tolerable in 20 cases. Average procedural time was 23.1 minutes. Mean VAS score prior to RFA was 8.1/10. Significant decrease of pain was noted at day 7 (3.3/10, p < 0.001