our website is for educational purposes only. the information provided is not a substitution for seeing a medical doctor. for the treatment of a medical condition, see your doctor. we update the site frequently but medicine also changes frequently. thus the information on this site may not be current or accurate.
What is Lumbar Spondylolisthesis?
The spine is composed of 34 bones called vertebre, which are stacked on top of each other and function to protect the spinal cord, while also allowing our bodies to remain flexable. If the spine was just one bone we would be as stiff as a lead pipe. Each of these bones has a hole in the middle where the spinal cord runs, and therefore its important for each of the vertebre to remain lined up with each other so that this hole doesn’t become narrowed and pinch the cord. The bones are held together by ligaments so that when you bend forward there is no sliding. However if these bones become loose and overly stretched out (like an old pair of underwear) then the vertebre can slide and lose their alignment. When a vertebre slips forward and hangs over its neighbor below, this is called “spondylolisthesis”. It occurs when ligaments become loose. It can also occur after a traumatic injury. This is because the vertebre is a bone that is thick in the front and the back (with the middle being mostly a hole for the spinal cord), however the front and back are connected by a thin bridge of bone on each side called the “pars intraarticularis”, and this can fracture because it’s a weak link of the bone. When these fracture, the front of the vertebre (called the vertebral body) can slip forward. The degenerative form of this disorder, where the ligaments become lax, is 8x more common in females because of hormonal changes that cause ligament laxity throughout the body.
How is Lumbar Spondylolisthesis diagnosed?
Patients complain of back pain and/or pain that radiates down their leg. This pain is very similar to the pain caused by a slipped disk or low back arthritis. Very tight hamstring muscles is a presentation that is unique to this condition but a finding that is difficult to identify when examining a person. Xrays are the best way to identify a slipped vertebre because you can visualize the bones and see if they are not properly stacked up. If spondylisthesis is suspected, additional spine xrays are obtained with a person flexing forward and leaning back to see how much the vertebral alignment changes with changes in posture. This gives a picture of how unstable the low back is. X-rays are great at showing the bone but don’t allow us to look at the nerves. Therefore MRIs are often ordered as well to see if the spinal nerves are being compressed as they branch off the spinal cord and exit the spine.
How is Lumbar Spondylolisthesis treated?
The treatment depends on the severity of someones complains of pain and the severity of the vertebral slip. The severity of slip is graded 1 to 4, with a grade 1 being <25% of the vertebre hanging over the edge, grade 2 is 25-50% slipped, grade 3 is 50-75% and grade 4 is >75%. Usually the slip is a grade 1, not severe and will respond well to antiinfammatory medicatinos and physical therapy. The vast majority of spondis will not be treated with surgery. However, if pain is persistently severe for >6 months and has not improved with medication and physical therapy then surgery is performed to realign the vertebral bones, decompress the nerves that are being pinched, and fuse the bone together so there is not further instability. This helps about 80% of people who get the surgery.
What is the long term outcome?
How well does it heal and what complications can occur?
The patients do well when treated appropriately.