Age-Related Association Between Unilateral Single-Channel and Double-Channel Surgery and Postoperative Multifidus Muscle Atrophy and Fat Infiltration

BACKGROUND: Unilateral biportal endoscopic laminotomy (UBE) and percutaneous endoscopic laminotomy (PEL) are minimally invasive spinal surgery (MISS) techniques used for unilateral and dual-channel endoscopic laminectomy. However, limited research has been conducted on lumbosacral multifidus muscle injuries in elderly individuals undergoing MISS for lumbar spinal canal stenosis. The objective of this study was to investigate the impact of single-channel and double-channel MISS on the multifidus muscle in elderly patients. MATERIALS AND METHODS: A total of 107 patients who underwent MISS were stratified into two cohorts: group A (<65 years) and group B (≥65 years). Preoperative imaging data, including magnetic resonance imaging, were gathered to classify the degree of stenosis based on the nerve root compression. The extent of multifidus muscle atrophy and fat infiltration was assessed by calculating the fat-free cross-sectional area (FCSA)/cross-sectional area (CSA) ratio before and after surgery through measurements of CSA and FCSA. Total cross-sectional area/FCSA were calculated using MRI cross-sectional T2WI. CONCLUSION: . 2025;48(1):12-19.].