The vertebrae are the box-shaped bones that stacked on top of eachother make up the spinal column. Each vertebrae should be neatly stacked on the one above and below. When views from the side, the spinal column had a normal S-shaped curvature (see picture), but each vertebrae should be neatly positioned on top of the vertebrae below. In spondylolisthesis, the vertebrae shift from their normal position, a condition often referred to as a "slipped vertebrae." Most often, this is a very slowly progressive condition.
Causes of SpondylolisthesisThere are six types of spondylolisthesis:
- Degenerative Spondylolisthesis
Degenerative spondylolisthesis is by far the most common cause of spinal segments slipping on top of eachother. Over time, aging causes damage to the tissues of the body, including the bones, joints, and ligaments that link the vertebral column together.
Chronic damage can lead to loss of stability of the spinal column. If the degenerative changes progress to a point when the ligaments and joints cannot hold the proper position of the spinal column, then degenerative spondylolisthesis is the result.
- Isthmic Spondylolisthesis
Isthmic spondylolisthesis is due to a specific bony defect in the spine called spondylolysis. Spondylolysis is a specific defect in one important link between adjacent spinal vertebrae. This specific defect is most commonly the result of repetitive microtrauma during childhood. Some sports are thought to make children more susceptible to developing spondylolysis, including gymnastics, diving, and football.
When spondylolysis occurs on both sides of the spinal column at one specific level, the vertebral column can lose stability. In these situations isthmic spondylolisthesis can be the result.
Symptoms of SpondylolisthesisThe symptoms of spondylolisthesis can be wide ranging from an incidental finding on x-ray (no symptoms) to severe back and leg pain with nerve damage.
Many cases of spondylolisthesis in children cause few symptoms. Intermittent back pain may be found, especially when arching the back.
When the nerves exiting the spinal cord, or the spinal cord itself, become pinched by the spondylolisthesis, then nerve symptoms can result. Common nerve symptoms seen are similar to symptoms seen with a herniated disc. The symptoms include:
- Leg pain
- Electric shock-like symptoms travelling down the leg
- Numbness or tingling in the legs and feet
- Muscle weakness of the legs
Treatment of SpondylolisthesisTreatment of spondylolisthesis is wide ranging, from observation to surgical stabilization of the spine. Determining the appropriate treatment plan is most dependent on the age of the patient, the type of slip, and the symptoms experienced by the patient.
If the slip is small and the symptoms are manageable, then treatment is most often with nonsurgical treatments. In children, this may include activity restrictions, such as withholding the child from participation in some sports.
When the slip is more significant, there may be a higher risk of the problem progressing, and surgery may be recommended. In addition, patients who have symptoms of nerve compression are more likely to have surgery recommended. Nerves can become permanently damaged if there is prolonged compression of the nerve.
Jones TR and Rao RD "Adult Isthmic Spondylolisthesis" J. Am. Acad. Orthop. Surg., October 2009; 17: 609 - 617.
Cavalier R, et al. "Spondylolysis and Spondylolisthesis in Children and Adolescents: I. Diagnosis, Natural History, and Nonsurgical Management" J. Am. Acad. Orthop. Surg., July 2006; 14: 417 - 424.