Effect of Sarcopenia on the Outcomes of Radiofrequency Ablation of Medial Branch Nerves for Lumbar Facet Arthropathy in Patients Aged 60 Years and Older: A Retrospective Analysis

Background/Objectives: Sarcopenia is defined by the progressive loss of muscle mass, strength, and/or physical performance associated with aging. Radiofrequency ablation (RFA) of the medial branch nerves is a well-established and effective treatment for lumbar facetogenic pain. While sarcopenia is associated with poor outcomes following epidural steroid injections and lumbar spine surgeries, its impact on clinical outcomes in patients undergoing RFA for facetogenic pain remains unexplored. This study aims to evaluate the influence of sarcopenia on treatment outcomes in this patient cohort. Methods: Patients were classified into sarcopenia (n = 35) and non-sarcopenia groups (n = 67) based on predefined psoas muscle index (PMI) thresholds. The primary outcomes included changes in back pain intensity and the proportion of responders at 1, 3, and 6 months following RFA. The secondary outcome was to identify demographic, clinical, and sarcopenia-related factors predictive of treatment response at each follow-up interval. Results: Both groups demonstrated statistically significant improvements in pain scores compared to baseline at all follow-up points. However, the median pain scores at 3 months post-RFA remained significantly higher in the sarcopenia group. Despite this, the proportion of responders did not differ significantly between the two groups at any time point. At 3 months, the absence of prior spinal surgery was identified as a significant predictor of treatment response. At 6 months, favorable outcomes were significantly associated with the absence of diabetes, no history of spinal surgery, and a higher PMI. Conclusions: Sarcopenia may influence the extent of pain improvement following medial branch nerve RFA. Additionally, patient-specific factors, such as diabetes, prior spinal surgery, and PMI, should be considered when predicting treatment outcomes.