Correlation Between Postoperative Changes in Imaging Parameters and Clinical Outcomes After Unilateral Biportal Endoscopic Decompression for Single-Level Lumbar Spinal Stenosis.

PURPOSE: This study aimed to investigate the correlation between imaging parameters and clinical outcomes in patients with lumbar spinal stenosis (LSS) who underwent unilateral biportal endoscopic decompression (UBED). PATIENTS AND METHODS: This retrospective study included 126 eligible patients who underwent UBED, with a mean follow-up duration of 2.6 years (range: 2.1-2.8 years). Clinical outcomes were evaluated using the Visual Analog Scale (VAS), Oswestry Disability Index (ODI), and the modified MacNab criteria. Imaging parameters related to LSS were assessed using X-ray, computed tomography, and magnetic resonance imaging (MRI) before and after UBED. Correlations between imaging parameters and clinical outcomes were subsequently analyzed. RESULTS: According to the modified MacNab criteria, 86.3% of patients achieved excellent or good outcomes. In patients with LSS, changes in the spinal canal area (SCA) and dural sac area (DSA) from preoperative to postoperative measurements were negatively correlated with VAS-back, VAS-leg, and ODI scores at the 2-year follow-up. CONCLUSION: UBED provides favorable clinical outcomes in patients with LSS. Specifically, increases in the SCA and DSA from preoperative to postoperative measurements are associated with lower VAS and ODI scores. These findings suggest that postoperative changes in SCA and DSA may serve as useful radiological indicators of clinical improvement following UBED.