Abstract
Introduction
The hypertrophy of the ligamentum flavum is known to be related to degenerative changes that are secondary to the aging process or mechanical instability. However, there has been no study to investigate the effect of chondroitin sulfate on hypertrophy of the ligamentum flavum. We aim to investigate the role of chondroitin sulfate on hypertrophy of the ligamentum flavum in lumbar spinal stenosis compared with that of lumbar disc herniation.
Materials and Methods
The concentrations of chondroitin sulfate were analyzed in the surgically obtained ligamentum flavum specimens from lumbar spinal stenosis (n = 34; mean age 65 years) and disc herniation (n = 24; mean age = 39.7 years) by immunohistochemical evaluation. The staining intensity and percentage of cells stained were recorded and these figures were converted into a weighted average intensity (WAI). The immunoreactivity score (IRS) was then calculated by multiplying WAI with TPS (total percentage of cells stained). The thickness of the ligamentum flavum was measured with axial T1-weighted magnetic resonance imaging. The biochemical and radiologic results were compared for these two conditions.
Results
A total of 94% (34/36) of specimens in the lumbar spinal stenosis had a IRS >50 as compared with 72% (16/22) in lumbar disc herniation; this difference is statistically significant (p = 0.011). The mean thickness of the ligamentum flavum was 3.96 mm (range, 2.67-5.75 mm) in lumbar spinal stenosis and 2.59 mm (range, 1.41-4.17 mm) in lumbar disc herniation; the difference between lumbar spinal stenosis and disc hernation was statistically significant (p < 0.05).
Conclusion
The current results suggest that higher expression of chondroitin sulfate might be related to the development of hypertrophy of the ligamentum flavum in lumbar spinal stenosis.
None declared