Lumbar Spondylolisthesis (Spinal Instability)
Spondylolisthesis is a condition in which one bone in your back (vertebra) slides over the bone below it. It most often occurs in the lower spine. In some cases, this may lead to nerve roots impingement, which can cause back pain and pain, numbness or weakness in the legs.
The vertebra of your spine come together at several small joints, which along with the disc, keep the bones in line while still allowing them to move. Spondylolisthesis is caused by a problem with one or more of these small joints or the disc that allows one bone to move out of line, These problems include:
- A defective joint that has been present since birth (congenital)
- A joint damaged by an accident or other trauma
- A vertebra with a stress fracture caused from overuse of the joint
- A joint damaged by arthritis or infection
Spondylolisthesis can affect children and teens involved in sports. Some sports, such as gymnastics or weightlifting, can overuse back bones to the point of causing stress fractures at a particular point in the vertebra (spondylolysis); this can result in spondylolisthesis or slippage.
Older adults can develop spondylolisthesis because wear and tear on the back leads to stress fractures. It can also occur without stress fractures when the disc and joints are worn down and slip out of place.
Symptoms of spondylolisthesis may include:
- Back or buttock pain
- Pain that runs from the lower back down one or both legs
- Numbness or weakness in one or both legs
- Difficulty walking
- Leg, back, or buttock pain that gets worse when bending or twisting
X-rays will show whether any of the vertebra in your back are out of alignment. Usually, this is supplemented with MRI and/or CT to determine if nerve impingement exists, and to help guide treatment.
Treatment varies depending on the severity of the condition. Most patients get better with strengthening and stretching exercises combined with activity modification, which involves avoiding hyperextension of the back. Other treatments such as epidural steroid injections and facet joint injections can help control pain in some cases as well.
When pain is extreme or bones continue to move excessively, or if there is nerve root damage related to the spondylolisthesis, surgery can sometimes help. Surgery may be done to remove bone or other tissue to take pressure off the spinal cord or nerves (decompression). Or surgery may be done to fuse the bones in position (TLIF, XLIF). Often both decompression and fusion are done during the same surgery.
Often these surgeries can be done in a minimally invasive manner allowing for less blood loss and quicker recovery. After any of these surgeries, patients may need to wear a back brace for a while. Later, rehabilitation therapy will help make muscles stronger and movement easier. When done with correct indications, including failed trials of conservative treatment, most patients respond very well to surgical treatment.