A Randomized, Placebo-Controlled Study to Assess the Efficacy of Lateral Branch Neurotomy for Chronic Sacroiliac Joint Pain

Objective. The objective of this study was to compare the efficacy of lateral branch neurotomy using cooled radiofrequency to a sham intervention for sacroiliac joint pain. Design. Fifty-one subjects were randomized on a 2: 1 basis to lateral branch neurotomy and sham groups, respectively. Follow-ups were conducted at 1, 3, 6, and 9 months. Subjects and coordinators were blinded to randomization until 3 months. Sham subjects were allowed to crossover to lateral branch neurotomy after 3 months. Subjects. Subjects 18-88 years of age had chronic (>6 months) axial back pain and positive response to dual lateral branch blocks. Interventions. Lateral branch neurotomy involved the use of cooled radiofrequency electrodes to ablate the S1-S3 lateral branches and the L5 dorsal ramus. The sham procedure was identical to the active treatment, except that radiofrequency energy was not delivered. Outcome Measures. The principal outcome measures were pain (numerical rating scale, SF-36BP), physical function (SF-36PF), disability (Oswestry disability index), quality of life (assessment of quality of life), and treatment success. Results. Statistically significant changes in pain, physical function, disability, and quality of life were found at 3-month follow-up, with all changes favoring the lateral branch neurotomy group. At 3-month follow-up, 47% of treated patients and 12% of sham subjects achieved treatment success. At 6 and 9 months, respectively, 38% and 59% of treated subjects achieved treatment success. Conclusions. The treatment group showed significant improvements in pain, disability, physical function, and quality of life as compared with the sham group. The duration and magnitude of relief was consistent with previous studies, with current results showing benefits extending beyond 9 months.