Esmat SM, Wan Zainuddin WAR, Tiw ZS, Razip S, Laili SAL, Rohidayah AM
Abstract: Background: Dynamic radiograph is commonly proposed to diagnose lumbar instability but no study was performed to prove the correlation with both symptoms and MRI findings. Objectives: The purpose of this study is to determine the correlation between lumbar segmental motion and MRI with clinical symptoms at the level of L4/L5 and L5/S1. Methods: A cross sectional study of 50 patients with back pain who have done MRI lumbosacral was performed between 1st April 2019 to 31st October 2019. Lumbosacral dynamic x-ray, assessment for visual analogue pain scale (VAS) and modified Oswestry disability index (ODI) were done during outpatient visit. Degree of disc degeneration (DD), facet joint osteoarthritis (FJO), and ligamentum flavum hypertrophy (LFH) were determined from MRI lumbosacral whilst the segmental motions were manually measured from dynamic x-rays. Horizontal motion ≥ 4 mm and angular motion of > 20° at L4/L5 and > 25° at L5/S1 are considered excessive. Results: The overall incidence of excessive horizontal motion was 10 % at L4/L5 and 12 % at L5/S1 while excessive angular motion was 14 % at both L4/L5 and L5/S1. At L4/L5, it was noted that FJO grade III and angular motion both had significant correlation to predict worsening VAS with p-value of 0.033 and 0.037, respectively. At L5/S1 level, only horizontal lumbar motion was found to have a statistically significant correlation to predict higher ODI score with p-value of 0.001. Conclusions: Comprehensive assessment both clinically and radiologically is paramount in determining the appropriate diagnosis and management of lumbar instability.
Keywords: lumbar vertebrae, segmental motion, instability, disc degeneration, facet joint osteoarthritis, ligamentum flavum hypertrophy