Analysis of the Relationship Between Modic Change and Spinopelvic Parameters in the Sagittal Plane

Correlation between sagittal balance and thoracolumbar elastic energy parameters in 42 spines subject to spondylolisthesis or spinal stenosis and 21 normal spines

The curvature of the lumbar spine plays a critical role in maintaining spinal function, stability, weight distribution, and load transfer. We have developed a mathematical model of the lumbar spine curve by introducing a novel mechanism: minimization of the elastic bending energy of the spine with respect to two biomechanical parameters: dimensionless lumbosacral spinal curvature c LS and dimensionless curvature increment along the spine CI. While most of the biomechanical studies focus on a particular segment of the spine, the distinction of the presented model is that it describes the shape of the thoracolumbar spine by considering it as a whole (non-locally) and thus includes interactions between the different spinal levels in a holistic approach. From radiographs, we have assessed standard geometrical parameters: lumbar lordosis LL, pelvic incidence PI, pelvic tilt PT, sacral slope ψ0 and sagittal balance parameter SB = sagittal vertical axis (SVA)/sacrum-bicoxofemoral distance (SFD) of 42 patients with lumbar spinal stenosis (SS) or degenerative spondylolisthesis (SL) and 21 radiologically normal subjects. SB statistically significantly correlated with model parameters c L5 (r = -0.34, p = 0.009) and -CI (r = 0.33, p = 0.012) but not with standard geometrical parameters. A statistically significant difference with sufficient statistical power between the patients and the normal groups was obtained for c LS, CI, and SB but not for standard geometrical parameters. The model provides a possibility to predict changes in the thoracolumbar spine shape in surgery planning and in assessment of different spine pathologies.

Study and analysis of the correlation between lumbar spondylolisthesis and Modic changes

Background

This study aimed to explore the risk factors of Modic changes in lumbar spondylolisthesis.

Methods

The distribution of Modic changes in different types of lumbar spondylolisthesis, degree of spondylolisthesis, and degree of intervertebral disc degeneration in patients with lumbar spondylolisthesis was observed and analyzed. Statistical analysis was conducted to assess whether intervertebral disc degeneration, local mechanical changes, etc. affect the occurrence of Modic changes. The risk factors of Modic changes in lumbar spondylolisthesis were further illustrated.

Results

The age in the lumbar spondylolisthesis with Modic changes group was younger than that in the lumbar spondylolisthesis without Modic changes group, and the bone mineral density was better in the lumbar spondylolisthesis with Modic changes group than that in the lumbar spondylolisthesis without Modic changes group, P < 0.05. The two groups statistically differed in intervertebral disc height (IDH) and disc angle on magnetic resonance imaging (MRI). In the classification of Modic changes, the incidence of type II was the highest. The incidence of Modic changes is higher in isthmic spondylolisthesis than in degenerative spondylolisthesis. With the aggravation of lumbar spondylolisthesis and intervertebral disc degeneration, the incidence of Modic changes gradually increased. Modic changes are most commonly seen in both the upper and lower endplates. Logistic regression analysis showed that the occurrence of Modic changes in lumbar spondylolisthesis was significantly correlated with IDH, disc angle on MRI, type of spondylolisthesis, degree of spondylolisthesis, and degree of intervertebral disc degeneration, P < 0.05.

Conclusions

The occurrence of Modic changes is related to the type of spondylolisthesis, the degree of spondylolisthesis, the degree of disc degeneration, the decrease of intervertebral disc height, and local stress angulation.

Correlation of Modic Changes with Sagittal Lumbopelvic Parameters

Purpose

The main aim of this retrospective study was to analyze lumbopelvic sagittal parameters among the three different types of Modic changes (MCs). Furthermore, correlations between the sizes of MCs and the number of involved lumbar levels with lumbopelvic parameters are investigated.

Methods

A total of 263 adult subjects with MCs at a single institution from September 2015 to October 2020 who underwent lumbar x-ray examinations and magnetic resonance imaging were included in this retrospective study. Types of MCs, sizes of MCs, lumbar levels involved by MCs as well as lumbopelvic sagittal parameters from each subject were evaluated by two authors.

Results

Lumbar lordosis (LL), sacral slope (SS), and pelvic incidence (PI) in subjects with MC grade 1 were significantly smaller than in those with MC grade 2 and grade 3 (p<0.05). Lumbopelvic sagittal parameters decreased significantly as the sizes aggravated (p<0.01). Triple lumbar levels with MCs showed a significant increase in PI-LL (p<0.05) and decrease in LL (p<0.01), SS (p<0.01), and PI (p<0.01) when compared to MCs at single and double lumbar levels.

Conclusion

MC grade 1, severe MCs, and lumbar multi-segmental MCs were significantly linked to lumbar sagittal imbalance.