Faculty Collaboration Database

MR imaging of lumbar spondylolysis: the importance of ancillary observations. AJR Am J Roentgenol 1997 Jul;169(1):233-9

Date

07/01/1997

Pubmed ID

9207531

DOI

10.2214/ajr.169.1.9207531

Scopus ID

2-s2.0-0030813994 (requires institutional sign-in at Scopus site)   57 Citations

Abstract

OBJECTIVE: The purpose of this study was to determine the frequency of characteristic ancillary MR findings in patients with lumbar spondylolysis.

MATERIALS AND METHODS: The radiology reports and clinical records of 64 patients (16 female, 48 male; 12-77 years old) with 66 levels of lumbar spondylolysis who had undergone MR imaging were retrospectively reviewed. Spondylolysis was established by conventional radiography in all 64 patients and by CT in 18 patients. The proportion of patients with spondylolysis in whom sagittal MR images showed ancillary findings of an increased sagittal diameter of the spinal canal, reactive marrow changes in the pedicle, or abnormal wedging of the posterior aspect of the vertebral body was retrospectively determined. This proportion was then compared with the proportion of patients in whom spondylolysis was correctly diagnosed by the initial interpreters of the MR images, who used only direct visualization of defects of the pars interarticularis to make the diagnosis.

RESULTS: Twenty (30%) of 66 levels of lumbar spondylolysis were misdiagnosed when the MR images were initially interpreted using direct visualization of defects of the pars interarticularis. An increased sagittal diameter of the spinal canal was the most common ancillary observation, occurring at 60 of 66 levels of lumbar spondylolysis. This finding was present in all patients with grade II, III, or IV spondylolisthesis, in 95% of patients with grade I spondylolisthesis; and in 77% of patients with no anterolisthesis. Thirty-two (48%) of 66 lumbar levels showed wedging of the posterior aspect of the vertebral body, which correlated significantly with the grade of spondylolisthesis. Reactive marrow changes in the pedicle distinct from normal adjacent levels were seen on MR images in 24(36%) of 66 levels of lumbar spondylolysis. On MR images, 97% of all levels of lumbar spondylolysis yielded one or more ancillary observations, including all 20 of the cases originally misdiagnosed.

CONCLUSION: The combined use of ancillary observations and direct visualization of pars interarticularis defects makes MR imaging effective in revealing lumbar spondylolysis.

Author List

Ulmer JL, Mathews VP, Elster AD, Mark LP, Daniels DL, Mueller W

Authors

Vincent Mathews MD Chair, Professor in the Radiology department at Medical College of Wisconsin
Wade M. Mueller MD Professor in the Neurosurgery department at Medical College of Wisconsin

MESH terms used to index this publication - Major topics in bold

Adolescent
Adult
Aged
Bone Marrow
Child
Female
Humans
Lumbar Vertebrae
Magnetic Resonance Imaging
Male
Middle Aged
Retrospective Studies
Spinal Canal
Spondylolysis