The Effect of Medial Branch Radiofrequency Ablation on Functional Spinal Stability and Lumbar Multifidi Muscle Architecture Assessed by Magnetic Resonance Imaging and Ultrasound Imaging

Radiofrequency ablation (RFA) for the lumbar spine (lower back) is a procedure used to treat lower back pain secondary to facet arthritis. The procedure ablates (burns) a small nerve that goes to the arthritic joint in the back. This nerve also innervates a muscle called the multifidus, thought to be important for lumbar stability. The investigators are conducting a study to evaluate if RFA has any impact on multifidi size, spinal stability, and overall function. The tools the investigators will be using to assess the multifidi muscles are musculoskeletal ultrasound, MRI, physical therapy assessment, and functional questionnaires. The goal of the study is to determine if RFA impacts the multifidi in a clinically significant fashion, causing atrophy, spinal instability, and/or functional decline.