Imaging correlation of the degree of degenerative L4-5 spondylolisthesis with the corresponding amount of facet fluid.
ABSTRACT The aim of this study was to correlate the degree of L4-5 spondylolisthesis on plain flexion-extension radiographs with the corresponding amount of L4-5 facet fluid visible on MR images.
Patients underwent evaluation at the Neurosurgical Spine Clinics of Stanford University Medical Center and National Health Insurance Medical Center (Goyang, South Korea) between January 2006 and December 2007. Only patients who were diagnosed with L4-5 degenerative spondylolisthesis (DS) and who had both lumbosacral flexion-extension radiographs and MR images available for review were eligible for this study. Each patient's dynamic motion index (DMI) was measured using the lateral lumbosacral plain radiograph and was the percentage of the degree of anterior slippage seen on flexion versus that seen on extension. Axial T2-weighted MR images of the L4-5 facet joints obtained in each patient was analyzed for the amount of facet fluid, using the image showing the widest portion of the facets. The facet fluid index was calculated from the ratio of the sum of the amounts of facet fluid found in the right plus left facets over the sum of the average widths of the right plus left facet joints.
Fifty-four patients with L4-5 DS were included in this study. Of these 54 patients, facet fluid was noted on MR images in 29 patients (53.7%), and their mean DMI was 6.349 +/- 2.726. Patients who did not have facet fluid on MR imaging had a mean DMI of 1.542 +/- 0.820; this difference was statistically significant (p < 0.001). There was a positive linear association between the facet fluid index and the DMI in the group of patients who exhibited facet fluid on MR images (Pearson correlation coefficient 0.560, p < 0.01). In the subgroup of 29 patients with L4-5 DS who showed facet fluid on MR images, flexion-extension plain radiographs in 10 (34.5%) showed marked anterolisthesis, while the corresponding MR images did not.
There is a linear correlation between the degree of segmental motion seen on flexion-extension plain radiography in patients with DS at L4-5 and the amount of L4-5 facet fluid on MR images. If L4-5 facet fluid in patients with DS is seen on MR images, a corresponding anterolisthesis on weight-bearing flexion-extension lateral radiographs should be anticipated. Obtaining plain radiographs will aid in the diagnosis of anterolisthesis caused by an L4-5 hypermobile segment, which may not always be evident on MR images obtained in supine patients.
Acta Orthopaedica 12/2014; 85(357):1-45. DOI:10.3109/17453674.2014.976807 · 2.45 Impact Factor
Journal of Spinal Disorders & Techniques 07/2014; DOI:10.1097/BSD.0000000000000126 · 1.89 Impact Factor
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ABSTRACT: Study Design. Case series studyObjective. To define diagnostic advancement of L-spine MR with axial loading device in patients with clinically suspected central spinal canal stenosis, and to show a relationship of facet joint instability with aggravated central spinal canal stenosis in axial loaded studies.Summary of Background Data. Although the axial loading device has been used several years, there have been very few reports about the usefulness of the axial loading device in clinical settings. Also, there has been no report about that the relationship between facet arthrosis and dynamic central spinal canal stenosis.Methods. Lumbar MRI with axial loading device was obtained in 54 patients. Axial images were evaluated with attention to 1) gross change of central spinal canal stenosis, 2) findings of facet joint, including arthrosis, effusion, effacement of effusion, and 3) formation of ventral synovial cyst after axial loading. In addition, dural sac cross sectional area (DSCSA) was measured in L3/4, L4/5 and L5/S1 levels to quantify the change of stenosis. Changes of neural foraminal stenosis, curvature and spondylolisthesis were evaluated with sagittal images.Results. With a use of axial loading device, the additional diagnosis of severe central spinal canal stenosis was made in 13 patients (25%) in both gross interpretation and quantitative study (DSCSA <75mm). The significant decrease of DSCSA was demonstrated in 22 patients (42%). The significant decrease was related to facet joint effusion and effacement of effusion.Conclusion. Measurable advancement in diagnosis of severe central spinal canal stenosis was possible with axial loaded MRI. Patients with facet joint instability had tendency to show significant changes in central spinal canal area.Spine 06/2013; DOI:10.1097/BRS.0b013e3182a0dfa5 · 2.45 Impact Factor