Prevalence of vertebral endplate modic changes in degenerative lumbar scoliosis and its associated factors analysis.

STUDY DESIGN: A retrospective study of modic changes (MCs) in degenerative lumbar scoliosis (DLS). OBJECTIVE: To investigate the prevalence of vertebral endplate MCs in DLS and explore their associated factors. SUMMARY OF BACKGROUND DATA: MCs are common in spinal degenerative diseases. Presently, most of the researches have been focused on investigating the relationship between MCs and chronic low back pain. Little has been known on the distribution of MCs in DLS and the relationship between MCs and scoliosis. METHODS: The image data of 120 patients who had been diagnosed with DLS in our hospital from March 2005 to March, 2011 were retrospectively reviewed as the study group. The image data of 89 patients who had been diagnosed with degenerative lumbar diseases without scoliosis were selected as the control group. The prevalence, type, and distribution of MCs in 2 groups were observed and compared. Disc degeneration, Cobb angle, body weight, and smoking were recorded in the study group, and the relationship of MCs with these influential factors was analyzed. RESULTS: Of 1440 endplates from 120 patients in the study group, 247 (17.2%) from 71 (59.2%) patients were found to have MCs. Compared with the control group, of 1068 endplates from 89 patients, 49 (4.5%) endplates from 21 (23.6%) patients were found to have MCs. The prevalence of MCs was significantly higher in the study group than that in the control group (P < 0.01). The MCs in DLS usually had asymmetric distribution with more frequent occurrence on the concave side than on the convex side of major or compensatory curve and mainly occurred at L2-L3, L4-L5, and L5-S1, which were in accordance with the common levels of apex vertebrae. Intervertebral disc degeneration, lumbar scoliosis, overweight and heavy smoking are considered as risk factors to MCs. By multinomial logistic regression analysis on these factors, the regression function was obtained: logit Y = -0.82 + 1.27D + 0.55S + 1.77 D × S (Y for MCs, D for intervertebral disc degeneration, S for scoliosis Cobb's angle and D × S for interaction of D and S). CONCLUSION: The prevalence of MCs in patients with DLS was significantly higher than that of patients without DLS. Most of them were type 2 and usually located on the concave side of apex vertebrae. MCs were significantly associated with intervertebral disc degeneration and lumbar scoliosis.

[Analysis of factors of formation and development about degenerative lumbar scoliosis].

OBJECTIVES: To investigate the correlation between scoliosis angle and the asymmetric index of degenerative lumbar scoliosis, the degree of intervertebral disc degeneration, decreased bone density. METHODS: As a retrospectively study, a total of 96 patients with degenerative lumbar scoliosis were retrospectively enrolled from January 2002 to August 2010 as scoliosis group, meanwhile 96 patients with lumbar spinal stenosis matched in gender, age and body mass index (BMI) were selected as control group. All patients were studied with plain radiographs, MRI and dual energy X-ray absorptiometry at presentation. Radiographic measurements include Cobb angle, the height of the convex and concave side of the apical disc and the contiguous disc superiorly and inferiorly, the height of the convex and concave side of the apical and the contiguous vertebral body superiorly and inferiorly in scoliosis group, the height of L(2-3), L(3-4), L(4-5) discs and the height of L(2-4) vertebral body in control group. The average relative signal intensity of lumbar intervertebral disc and cerebrospinal fluid in T2WI sagittal image was measured in apex intervertebral disc and adjacent discs by Adobe Photoshop 6.0 in scoliosis group, which was measured in L(2-3), L(3-4), L(4-5) disc in control group. The bone density of lumbar, femoral neck, trochanter, and Ward's triangle regions were measured with dual-energy X-ray absorptiometry. RESULTS: The intervertebral disc height in convex side was greater than the height in the concave side [(40 ± 7) mm vs. (28 ± 7) mm, P < 0.01], the vertebral body height in convex side was greater than the height in the concave side [(76 ± 12) mm vs. (72 ± 10) mm, P = 0.016] in scoliosis group. There was significant statistically difference in the degenerative degree of intervertebral discs between two groups (P = 0.003). There was significant statistically difference of the average T-value and the rate of osteoporosis between two groups (P < 0.01). Multiple linear regression analysis showed that the asymmetric disc index, the degenerative degree of intervertebral disc and osteoporosis were the predominant correlative factors, which affected the development of degenerative lumbar scoliosis. CONCLUSIONS: Degenerative lumbar scoliosis is always accompanied by the height asymmetry of intervertebral discs and vertebral body from convex and concavity sides. There is positive correlation between the angle of scoliosis and the asymmetric disc index, the degeneration of intervertebral disc, and negative correlation between the angle of scoliosis and the bone density (T-value).

[Correlation between intervertebral disc-endplate degeneration and bony structural parameter in adult degenerative scoliosis and its significance].

OBJECTIVES: To analyze the correlation between intervertebral disc-endplate degeneration and bony construction parameter and to explore its roles in adult degenerative scoliosis. METHODS: The imaging data of 79 patients with adult degenerative scoliosis from March 2005 to March 2010 were retrospectively reviewed as the study group. The imaging data of 41 patients with adolescent idiopathic scoliosis were selected as the control group. The vertebral body and intervertebral height in both sides on frontal X-ray, and the facet joint orientation in both sides on CT scan were measured respectively. The average vertebral body height, average intervertebral disc height and average facet orientation were regarded as bony structural parameters. The quantitative grading methods were used in the intervertebral disc and endplate degeneration. The relationship of bony construction parameter and intervertebral disc-endplate degeneration, and the relationship of bony construction parameter and Cobb's angle of scoliosis were analyzed by comparing all bony construction parameters in both groups. RESULTS: Analyzed by paired-t test, the intervertebral height, vertebral body height and facet joint orientation between convex and concave sides of the study group were of significant difference (t = 3.411, 2.623 and 2.085, P < 0.05). The intervertebral height between convex and concave sides of the control group were of significant difference (t = 3.276, P < 0.01), while the vertebral body height and the facet joint orientation were of no statistical significance (t = 1.572 and 1.493, P > 0.05). By linear correlation and regression analysis, the asymmetric degree of bony construction parameter showed good correlation with the score of intervertebral disc-endplate degeneration (-1 < r < 1, P < 0.05), which was positively correlated with Cobb's angle of scoliosis (0 < r < 1, P < 0.05). Linear regression existed between asymmetric degree of bony construction parameter and Cobb's angle (F = 427.342, P < 0.01). The regression function was obtained: Cobb's angle = -8.904+8.136 × IAD + 3.274 × VAD-0.713 × FAD (IAD: intervertebral asymmetry degree, VAD: vertebral asymmetry degree, FAD: facet joint asymmetry degree). CONCLUSIONS: The asymmetric change of bony construction exists in adult degenerative scoliosis, which significantly correlated with intervertebral disc-endplate degeneration and Cobb's angle of scoliosis. The asymmetric bony construction parameter probably plays a biomechanical role in the progression of scoliosis, which maybe the reason for the asymmetric degeneration of intervertebral disc-endplate.