Spondylolisthesis is divided into five major types based on the location and cause of the condition.
1. Pathologic
This type of spondylolisthesis is caused by weakness of the bone, due to a disease, a tumor, or other diseases of the bone.
2. Dysplastic
This type of spondylolisthesis is caused by a birth defect resulting in abnormal facet formation.
3. Isthmic
Spondylolisthesis of this type is caused by a defect in a part of the vertebra called the pars interarticularis.
4. Degenerative
Degenerative spondylolisthesis is due to arthritis causing misalignment of the spine.
5. Traumatic
This type of spondylolisthesis is caused by trauma to the vertebrae. A fracture of the pedicle, lamina, or facets can cause the vertebra to slip forward.