Kryorhizotomy:: an alternative technique for lumbar medial branch rhizotomy in lumbar facet syndrome

Object. The authors conducted a prospective study to investigate the efficacy of kryorhizotomy, an alternative procedure for lumbar medial branch neurotomy, in the treatment of lumbar facet syndrome (LFS). Methods. Fifty patients with chronic low-back pain, in whom pain was relieved by controlled diagnostic medial branch blocks of the lumbar zygapophyseal (facet) joints, underwent lumbar medial branch kryorhizotomy. Outcome was evaluated using the Visual Analog Pain Scales and assessment of work capacity. All outcome measures were repeated at 6 weeks, 6 months, and I year after surgery. At I-year follow-up examination, 31 (62%) of 50 patients experienced a good response to lumbar facet kryorhizotomy. Good results with pain relief of 50% or more were obtained in 85% of patients without previous spinal surgery but only in 46% who had undergone previous spinal surgery. This difference was statistically significant. In five patients (16%) in whom a good initial benefit was observed but who experienced increased pain within 6 weeks after kryorhizotomy, the beneficial result was regained after an early repeated procedure. There were no side effects. Overall, 19 (38%) of 50 procedures were not considered successful. In six of these 19 cases a rigid stabilization of the involved segment provided permanent pain relief. Conclusions. Based on this study, patients with LFS who have not undergone previous spinal surgery benefit significantly from percutaneous lumbar kryorhizotomy. Kryorhizotomy, which has virtually no risk, seems to be a valuable alternative technique to lumbar medial branch neurotomy.