This is a big word that is hard to pronounce, so let me break it down for you. Spondylo is a Greek word for spine and listhesis means to slip. This is not a slipped disc, rather it refers to one vertebral body slipping forward on another so that two segments of the spine are out of alignment.
This occurs primarily under two circumstances.
In both cases the result is the same. The symptoms usually always include back pain but often include leg pain that radiates to the foot (or both feet). Leg pain can actually be the predominant symptom and often leads to the first doctor visit. This is because leg pain, which is actually nerve pain, is harder to tolerate than back pain. This results from the bones being out of alignment which leads to pinching of nerves.
We do have non-operative techniques to help with these problems but very often the best solution is surgery. Even if the non-operative means are successful the symptoms often return. The surgery for these problems includes Spinal Fusion and some type of laminectomy is usually needed. The term laminectomy can be broken down as well to help us understand what it means. Lami- refers to lamina, which is the bony covering on the back of the spine that covers the spinal canal and nerves while –ectomy means to remove something. For example an appendectomy is removal of the appendix. A laminectomy is used to tack the pressure of the nerves that may have been pinched by the misaligned or slipped bones. If you only have back pain and no leg pain then fusion alone may all that is needed.