Does medial branch radiofrequency neurotomy accelerate degenerative lumbar spondylolisthesis compared to natural progression? A cross-sectional cohort study

Lumbar radiofrequency neurotomy (LRFN) effectively treats lumbar zygapophyseal joint pain by coagulating medial branch nerves (MBNs) carrying nociceptive signals. MBNs also innervate deep paraspinal muscles. There is a paucity of literature on whether LRFN accelerates the progression of vertebral displacement in patients with degenerative lumbar spondylolisthesis (DLS). Compare the rate of spondylolisthesis progression in adults with DLS who underwent LRFN to the 2% annual rate of progression expected by natural history. Cross-sectional cohort study. Consecutive patients with pre-existing DLS who underwent LRFN for zygapophyseal joint-mediated low back pain were identified. Patient demographics, LRFN procedure details, and radiographic images confirming Meyerding Grade (I-II) spondylolisthesis were collected from electronic medical records. The quantitative magnitude of spondylolisthesis progression and the annualized rate were calculated from pre-and post-LRFN radiographs. Data were analyzed using Wilcoxon signed-rank tests and a linear regression model. 152 patients (mean age 65.9 ± 12.3 years; 59.2% female) met eligibility criteria and were included in the analyses. Average time to radiographic follow-up was 35.6 ± 24.7 months post-LRFN. The average spondylolisthesis progression rate of 1.63 ± 2.91% per year calculated for the LRFN cohort was significantly lower than the 2% annual rate of progression associated with natural history (p < 0.001). None of the included covariates, such as age, BMI, LRFN laterality, number of levels denervated, or history of prior lumbar spinal surgery, were significantly associated with the average annual rate of progression. Our results suggest that spondylolisthesis progression rate is no different or worse than the expected natural progression rate in patients with pre-existing DLS who have undergone LRFN.