Evaluation of changes in lumbar neuroforaminal dimensions in symptomatic young adults using positional MRI

To investigate the changes of lumbar neural foramina size during dynamic motion using positional MRI. Two hundred and fifty neural foramina from 50 patients were analyzed. Lumbar foraminal height, width, and area parameters from L1 to S1 were evaluated for changes in extension, neutral, and flexion positions on T2 parasagittal positional MRI images, and were correlated to lumbar angular motion. One-way analysis of variance (ANOVA) and post hoc analysis were used to examine the differences between levels and positions. Compared to the neutral position, almost all lumbar foraminal parameters (height, width at inferior level, and area) increased in flexion and decreased in extension at all levels, except for L5–S1 foraminal width at superior and middle levels. The foraminal height and area in all lumbar segments except L5–S1 increased as the lumbar angular motion changed from extension to flexion in