Diagnosis and evaluation of spondylolisthesis and/or spondylolysis on axial CT.

A critical review was made of the CT findings in 300 patients who underwent axial CT of the lumbar spine in which spondylolysis and/or spondylolisthesis had been diagnosed. Findings indicate that axial CT is superior to conventional radiographs in several areas: (1) for consistent and accurate demonstration of spondylolysis, (2) for disclosing the various changes in the apophyseal joints associated with degenerative and reverse spondylolisthesis, and (3) for uncovering minimal degrees of spondylolisthesis by the presence of a pseudobulging disk in many cases with equivocal or negative radiographs. Axial CT is a highly accurate method for diagnosing and evaluating spondylolysis and all types of spondylolisthesis.