J Korean Radiol Soc.  1990 Dec;26(6):1249-1257. 10.3348/jkrs.1990.26.6.1249.

CT Findings of spondylolysis and spondylolisthesis

• Gong JC
• Kim HJ
• Kim JH
• Shin HJ
• Kim DK
• Ha CK
• Lim BH
• Chung SH

• KMID: 2358786
• DOI: http://doi.org/10.3348/jkrs.1990.26.6.1249

Abstract

Spondylolysis is a common condition, but CT findings have been paid relatively scanty attention in journalpublication. The authors reviewed lumbar spine CT of 42 patients who were diagnosed as spondylolysis and /orspondylolisthesis in Gyeong Sang National University Hospital. The results were as follows. 1. In 27 cases ofspondylolysis, it most frequently occurred at L5(55.5%) with 88.3% of bilaterality. The defect of the parsinterarticularis was most clearly visible on the slice at or just above the neural foramen. The appearance of thedefect had a horizontal plane(88.9%), an irregular surface (85.1%), a non-sclerotic margin(88.9%), and a medialproturbance of the medial aspect of the bone just anterior to the defect (77.8%). Spondylolisthesis was associatedin 20 of 27 cases (74%), which was demonstrated as an elongation of the anteroposterior diameter of the spinalcanal and a pseudobulging disk at defect level in all cases. The degree of the anterior displacement was Grade Iin fourteen (55.6%) and Grade II in five(18.7%). 2. Degenerative spondylolisthesis was found in 18 cases and mostfrequently occurred at L4-5 lelvel (83.3%). The characteristic findings were a vertically-orientedjointplane(66.7%), a posterior displacement of the anterior facet with reference to the posterior facet (50%), bonyspurs in the anterior facet (94.1%), a vacuum facet joint(55.6%), and an increased facet joint distance(50%). 3.Spinal stenosis and disk herniation were two most frequent associated abnoramlities, they were found at a rate of44.4% and 14.8% in spondylolysis and at a rate of 72.2% and 33.3% in degenerative spondylolisthesis. In cases ofdisk herniation, it frequently occurred just above the level of the defect (2/4) in spondylolysis, in contrast todegenerative spondylolisthesis in which it was most frequent at the same level(4/6). In conclusion, CT must be thehighly accrate method for diagnosing and evaluating spondylolysis and all types of spondylolisthesis.

MeSH Terms

Constriction, Pathologic
Humans
Methods
Spine
Spondylolisthesis*
Spondylolysis*
Vacuum
Zygapophyseal Joint