070819 Lower back pain: Spondylolysis and Spondylolisthesis
By Rickey Dale Crain
The spine or vertebral column consists of a series of vertebrae held together to give support for the spinal cord and nerves arising from it. Each vertebra consists of an anterior vertebral body, and a posterior bony ring with two superior facets and two inferior facets that articulate with the neighboring vertebrae. These articulations form the posterior facet joints that provide stability to the spine. In spondylolysis, there is a defect in the pars interarticularis (which literally means the “piece between the articulations”). So spondylolysis means a defect in the thin isthmus of bone connecting the superior and inferior facets, and could be unilateral (involving one side) or bilateral (involving both sides). Although the defect can be found at any level, the commonest vertebra involved is the 5th Lumbar vertebra (or L5). In cases of bilateral spondylolysis, the posterior articulations can no longer provide the posterior stability, and anterior slipping of the L5 vertebra over the sacrum could result. This slip is called Spondylolisthesis.
Spondylolysis is the commonest cause of spondylolisthesis, and is sometimes referred to as isthmic spondylolisthesis, since the defect is in the isthmus. But there are other causes of spondylolisthesis. In children born with underdeveloped facet joints (dysplastic joints), spondylolisthesis can also result, and is sometimes referred to as dysplastic spondylolisthesis. More rarely, any infection or tumor affecting the posterior bony ring including the facet joints can also cause instability and spondylolisthesis.
NOTICE: The information presented is for your information only, and not a substitute for the medical advice of a qualified physician. The author nor the publisher will be responsible for any harm or injury resulting from interpretations of the materials in this article.
Rickey Dale Crain
IPF / WPC / AAU World Champion
York Barbell Hall of Fame / USPF Hall of Fame
3803 North Bryan Road
Shawnee, Oklahoma 74804 USA