What Is Spondylolisthesis?
Spondylolisthesis (spon-duh-low-lis-THEE-sis) happens when the front part of a
vertebra (bone in the spine) slides away from the back part. In kids and teens, it's
often a complication of spondylolysis,
and is a common cause of lower back pain in these age groups.
Spondylolisthesis usually is mild and heals with rest and other "conservative"
(or nonsurgical) treatments. However, sometimes it can be severe and need surgery
to fix the problem.
How Does Spondylolisthesis Happen?
The spine (or backbone) has 33 bones called vertebrae (VER-tuh-bray). Nine vertebrae
are fused together to form the tailbone, and the other 24 are in the back. The lumbar
vertebrae are in the lower back and closest to the tailbone. This is where spondylolisthesis
usually happens.

Sometimes the front and back parts of one of the vertebra aren't connected. This
happens because of a fracture (break) in the part of the vertebra called the pars
(or pars interarticularis). Each vertebra has two pars, one on the left side and one
on the right. If both pars are fractured, the front part of the vertebra can slide
away from the back part.
Most of the time, the front slides away only a little bit. But if it slides away
a lot, it can cause the spinal cord and nerve roots to become pinched.
Some kids are born with a spondylolisthesis and some cases probably are genetic
(passed down by parents to their children). Spondylolisthesis can get worse while
kids are growing and even into adulthood.
What Are the Signs of Spondylolisthesis?
Many people with spondylolisthesis don't realize that they have it. Their backs
might feel just fine despite a vertebra being out of place.
When there are symptoms, they often include:
- pain in the lower back that might feel like a muscle strain
- pain in the thighs and buttocks
- stiff muscles and tenderness in the lower back
- muscle tightness, especially in the hamstring muscles
If the vertebra slips far enough to press on the spinal cord or smaller nerves,
it can cause increased pain and, in more serious cases, nerve damage. Signs of this
include:
- pain that radiates down the legs
- weakness in the legs or trouble walking
- trouble peeing or bladder accidents
- numbness and tingling in the groin and/or buttocks
Who Gets Spondylolisthesis?
Young people are more at risk for spondylolysis and spondylolisthesis because their
bones are still growing, especially during a growth spurt.
Kids and teens who play sports and do activities that can strain the lower back
or that involve a lot of lower-back stretching — like football, weightlifting,
gymnastics, volleyball, ballet, golf, and wrestling — are especially likely
to have these problems.
How Is Spondylolisthesis Diagnosed?
Besides doing a physical exam, health care providers will order X-rays of the lower
back to look for spondylolisthesis. X-rays can show if a vertebra has slipped out
of place.
Sometimes, other imaging tests are done — such as a CT (computed tomography)
scan or a lumbar MRI
scan — to get a better look at the back and to see if the slipped vertebra is
affecting the nerves.