Spondylolisthesis
This condition occurs when one of your vertebrae slips forward over the bone below it and is most common in the lower spine area.
Many times, spondylolisthesis squeezes the spinal cord or nerves. The condition often co-occurs with facet joint arthropathy (degeneration). Most common symptoms caused by this condition are back and buttock pain, numbness in the legs and pain that runs from the lower back down to the legs, difficulty walking.