GREAT VESSEL BIFURCATION AND LUMBOSACRAL ANGULATION ASSESSMENT ON ROUTINE LUMBAR SPINE MRI FOR IDENTIFICATION OF AN OPTIMAL ANTERIOR PLATE SIZE AND SHAPE IN STAND-ALONE LUMBO-SACRAL FUSION

Objective:The aim of this study was to define a method to identify the location of the great vessel bifurcation (GVB) in relation to the L5/S1 disc and measure the lumbo-sacral angle (LSA) at L5/S1 using routine lumbar spine MRI images on standard PACS software. The information can be used for surgical planning of anterior lumbar interbody fusion (ALIF) at L5/S1 with a plate and cage.Method:Axial and sagittal T2 sections of 192 lumbar spine MRI scans were viewed simultaneously to classify the position of the GVB and the LSA. A further 75 scans were assessed independently by 2 examiners (E1/E2) utilizing the same classification to record the GVB position (High (H), Middle (M), Low (L)) and size of the LSA using standard radiology software. Twenty five images were randomly selected for repeat measurements one month later.Results:Inter and Intra-observer agreements were excellent for LSA (0.92, R1=0.92, R2=0.94) and moderate for GVB (0.76, R1=0.85, R2=0.75). Reduced GVB correlation was primarily observed in ...