Spondylolisthesis

Spondylolisthesis refers to a condition based on image findings such as X-ray, CT scan and MRI in which one vertebral body has slipped forward on the vertebrae below, most commonly the fifth vertebra on the sacrum. There are two main types: isthmic spondylolisthesis, where a small stress fracture has occurred in part of the bone that connects the body to the back of the vertebra, and degenerative spondylolisthesis, in which the bones, joints, and ligaments in the spine over time gradually become weak and less able to hold the spinal vertebra in alignment.

This condition is most often discovered by accident when an individual has an x-ray for an unrelated reason. In fact, studies have found that while about 5% of the population have spondylolithesis, most do not suffer any lower back pain. In other words people with spondylolisthesis are no more likely to suffer lower back pain than anyone else in the population.