Isthmic spondylolisthesis.

Isthmic spondylolisthesis, which is demonstrated in 4 to 8% of the general population, is one of the most common types of spondylolisthesis. The three subtypes of this condition all manifest some variation of a pars interarticularis defect as a result of recurrent injury to that structure. A multifactorial origin is postulated for this disease; mechanical, hereditary, and hormonal factors are believed to play a role. Presenting signs and symptoms may include those referable to neurological compromise or those related to the spinal deformity. The majority of patients with spondylolysis and spondylolisthesis respond to conservative, nonoperative treatment. Pain, neurological compromise, and cosmetic defects unresponsive to traditional therapies may require surgical intervention. Surgical options include any combination of the following: neural decompression, bone fusion, instrument-assisted fusion, and reduction. In this paper, the natural history and treatment options are presented, and the supporting literature is reviewed.