@amberrose @ray666 Hello Nance and Ray. The term is actually spondylolisthesis, but I was trying to use common language that would make sense. Think of it like this. You have a string with large beads on it. The string is the spinal cord and each bead is a vertebra. If you pull on a bead to offset it, it pulls on the string of you pull it hard enough. If a spinal disc is allowing movement of the vertebrae in any forward, back or sideways direction, that is called listhesis. My reports stated I had retrolisthesis which is (backward movement) of C5 over C6. It meant that when I bent my neck, my C5 vertebra was sliding backward past C6 by 2 millimeters, so my vertebrae were not stacked perfectly in line with each other. Your spine changes position when you lay down, and if you have spondylolisthesis, it can cause spinal nerves to get compressed if the vertebrae are moving out of alignment. The spinal nerve exit the spine between the vertebrae. If that is something that you can change and reproduce the results with a change in position, make sure you explain that to your doctor. Sometimes spine surgeons take a standing full body X-ray of the spine for this reason, to show if the vertebrae are slipping past each other which can be common with spinal deformity cases. The standing vs laying down images can show very different alignment.