Degenerative spondylolisthesis or “spondy” is a disorder that causes the slip of one vertebral body over the one below and it happens as a result of aging and wear and tear on the discs, joints, and ligaments of the spine over time. The degeneration causes the two vertebrae to become ‘loose,’ leading to the slip. Spondy can be either fixed (slippage stays the same with motion) or dynamic (slippage worsens with motion).