Changing body position alters the location of the spinal cord within the vertebral canal: a magnetic resonance imaging study

Both the CM and associated nerve roots shift consistently and significantly anteriorly when moving from the supine to the lateral position with knees and hips flexed, which may provide a greater margin of safety during neuraxial blockade than might be predicted. However, the absence of significant cranial movement of the CM along the cranio-caudal axis still makes the spinal cord vulnerable to injury during lumbar neuraxial blockade.