Ann Rehabil Med.  2018 Aug;42(4):584-590. 10.5535/arm.2018.42.4.584.

A Dynamic Magnetic Resonance Imaging Study of Changes in Severity of Cervical Spinal Stenosis in Flexion and Extension

• Lee Y
• Kim SY
• Kim K

• KMID: 2420051
• DOI: http://doi.org/10.5535/arm.2018.42.4.584

Abstract

OBJECTIVE
To evaluate changes in the severity of cervical spinal stenosis (CSS) in flexion and extension and determine whether the rate of change with motion varied with severity.
METHODS
The study included 92 symptomatic patients with a mean age of 57.80±10.41, who underwent cervical spine dynamic magnetic resonance imaging. The severity of stenosis was evaluated using a semi-quantitative CSS score, ranging from 0 (no spinal stenosis) to 18 (severe stenosis). Radiological evaluation included flexion, neutral, and extension measurements, as determined by the C2-C7 Cobb angle. The severity of stenosis was represented by the total CSS score. The total CSS score in flexion, neutral, and extension positions was compared using repeated measures one-way analysis of variance. The change rate of stenosis per angle motion (CRSPAM) was defined as change in total CSS score divided by change in Cobb angle. The correlation of CRSPAM with severity of stenosis, represented by total CSS score in neutral position, was evaluated using Pearson correlation analysis.
RESULTS
The total CSS score was significantly higher in extension (6.04±2.68) than in neutral position (5.25±2.47) (p < 0.001), and significantly higher in neutral than in flexion position (4.40±2.45) (p < 0.001). The CRSPAM was significantly and positively correlated with total CSS score in neutral position in the flexion-extension range (r=0.22, p=0.04) and flexion-neutral range (r=0.27, p=0.01).
CONCLUSION
In symptomatic CSS patients, the radiological severity of stenosis increases with extension and decreases with flexion. In patients with CSS, the rate of variation in spinal stenosis increases with increased severity.

Keyword

Spinal stenosis; Cervical vertebrae; Magnetic resonance imaging; Cervical spondylotic myelopathy; Dynamic MRI

MeSH Terms

Cervical Vertebrae
Constriction, Pathologic
Female
Humans
Magnetic Resonance Imaging*
Spinal Stenosis*
Spine

Figure

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  Fig. 1. Illustrative case of cervical dynamic magnetic resonance imaging in left-to-right flexion, neutral, and extension positions.

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  Fig. 2. Total cervical spinal stenosis (CSS) score in flexion, neutral, and extension positions.

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  Fig. 3. Change rate in stenosis per angle motion in flexion and extension (A), flexion and neutral (B), and neutral and extension (C) ranges in relation to total cervical spinal stenosis (CSS) score in neutral position.

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