Can clinical presentation predict radiologically confirmed cauda equina syndrome: retrospective case review of 530 cases at a tertiary emergency department

Abstract

Purpose: Cauda equina syndrome (CES) may have significant individual consequences if diagnostic delays occur. Our aim was to evaluate the presenting subjective and objective features of patients with suspected CES in comparison to those with radiologically confirmed cauda equina compression (CEC). Methods: This was a retrospective analysis of all cases presenting with suspected CES to a tertiary emergency care unit over a two-year period. CEC was defined as radiological confirmation of CEC by Consultant Musculoskeletal (MSK) Radiologist report (MSK-CEC) and by measured canal occupancy due to an acute disc extrusion (> 75%)[measured by a Senior Spinal Surgeon (SP-CEC)]. Routine data collection was compared between categories. Chi square, multivariate regression analyses and ROC analysis of multiple predictors was performed. Results: 530 patients were included in this analysis, 60 (11.3%) had MSK-CEC, and 470 had NO- CEC. Only 43/60 (71.7%) had emergent surgery. Those with MSK-CEC and SP-CEC were statistically more likely to present with bilateral leg pain [(MSK-CEC OR 2.6, 95%CI 1.2, 5.8; p = 0.02)(SP-CEC OR 4.7, 95%CI 1.7, 12.8; p = 0.003)]; and absent bilateral ankle reflexes [(MSK-CEC OR 4.3; 95% CI 2.0, 9.6; p < 0.001)(SP CEC OR 2.5; 95%CI 1.0, 6.19; p = 0.05)] on multivariate analysis. The ROC curve analysis acceptable diagnostic utility of having SP-CEC when both are present [Area under the curve 0.72 (95%CI 0.61, 0.83); p < 0.0001]. Conclusion: This study suggests that in those presenting with CES symptoms, the presence of both bilateral leg pain and absent ankle reflexes pose an acceptable diagnostic tool to predict a large acute disc herniation on MRI scan.