Association between visual degeneration of intervertebral discs and the apparent diffusion coefficient.

The value of apparent diffusion coefficient (ADC) measurements in intervertebral disc has been studied because ADC provides an estimate of free diffusion of unbound water and could be used as a quantitative tool to estimate degenerative changes. However, the challenging nature of diffusion imaging of spine and limited numbers of subjects in earlier studies has produced contradictory findings. We aimed to determine the relation between ADC and visual degenerative changes in lumbar intervertebral discs in a sufficiently large homogeneous study group. Lumbar spines of 228 volunteer middle-aged men were MR imaged at 1.5 T including anatomic and diffusion-weighted imaging. ADC values, T2 signal intensity and height, and width of the three lowest lumbar intervertebral discs were measured and disc degeneration visually graded. The calculated average ADC of 530 measured discs was 2.01 x 10(-3) mm(2)/s+/-0.29 (+/-S.D.). The reduction in ADC between visually normal and moderately degenerated discs was 4%. Severely degenerated discs showed 5% larger ADC values than normal discs, presumably due to free water in cracks and fissures of those discs. T2 signal intensity of the disc was significantly correlated with the ADC values, whereas other measured parameters did not show correlation. There was no evident difference in ADC between the studied anatomic lumbar levels. Because there is considerable overlap between ADC values of normal and degenerated discs, we conclude that ADC measurements of intervertebral discs, at least with current technology, have limited clinical value.

Genetic factors are associated with modic changes in endplates of lumbar vertebral bodies.

STUDY DESIGN: A cross-sectional genotype-phenotype evaluation. OBJECTIVE: To evaluate the genetic background to Modic changes in an occupational cohort. SUMMARY OF BACKGROUND DATA: Modic changes are vertebral endplate changes visible in magnetic resonance imaging. Twin studies suggest that intervertebral disc degeneration may be primarily explained by genetic factors, but no data exist on genetic factors of Modic changes. METHODS: Thirteen variations in 8 genes (COL9A2, COL9A3, COL11A2, IL1A, IL1B, IL6, MMP3, and VDR) were genotyped in an occupational cohort of 159 male train engineers and 69 male paper mill workers. All the subjects were scanned by magnetic resonance imaging and evaluated for Modic changes. RESULTS: Out of the 228 subjects, 128 (56%) were found to have Modic changes at one or more disc levels, exclusively of type I in 15%, of type II in 32%, and of both type I and type II in 10%. None of the single nucleotide polymorphisms was significantly associated with Modic changes when analyzed independently, but when gene-gene interactions were evaluated, interleukin-1A (IL1A) and matrix metalloproteinase-3 (MMP3) polymorphisms together were associated with type II Modic changes (OR = 3.2, 95% CI = 1.2-8.5; P = 0.038), as was the IL1 gene cluster together with the MMP3 polymorphism (OR = 8.14, 95% CI = 1.72-38.44; P = 0.008). DISCUSSION: This is the first study evaluating the role of genetic factors in relation to Modic changes. Genetic variations in the IL1 cluster and the MMP3 gene together were found to be significantly associated with type II Modic changes.

Are the determinants of vertebral endplate changes and severe disc degeneration in the lumbar spine the same? A magnetic resonance imaging study in middle-aged male workers.

BACKGROUND: Modic changes are bone marrow lesions visible in magnetic resonance imaging (MRI), and they are assumed to be associated with symptomatic intervertebral disc disease, especially changes located at L5-S1. Only limited information exists about the determinants of Modic changes. The objective of this study was to evaluate the determinants of vertebral endplate (Modic) changes, and whether they are similar for Modic changes and severe disc degeneration focusing on L5-S1 level. METHODS: 228 middle-aged male workers (159 train engineers and 69 sedentary factory workers) from northern Finland underwent sagittal T1- and T2-weighted MRI. Modic changes and disc degeneration were analyzed from the scans. The participants responded to a questionnaire including items of occupational history and lifestyle factors. Logistic regression analysis was used to evaluate the associations between selected determinants (age, lifetime exercise, weight-related factors, fat percentage, smoking, alcohol use, lifetime whole-body vibration) and Modic type I and II changes, and severe disc degeneration (= grade V on Pfirrmann's classification). RESULTS: The prevalences of the Modic changes and severe disc degeneration were similar in the occupational groups. Age was significantly associated with all degenerative changes. In the age-adjusted analyses, only weight-related determinants (BMI, waist circumference) were associated with type II changes. Exposure to whole-body vibration, besides age, was the only significant determinant for severe disc degeneration. In the multivariate model, BMI was associated with type II changes at L5-S1 (OR 2.75 per one SD = 3 unit increment in BMI), and vibration exposure with severe disc degeneration at L5-S1 (OR 1.08 per one SD = 11-year increment in vibration exposure). CONCLUSION: Besides age, weight-related factors seem important in the pathogenesis of Modic changes, whereas whole-body vibration was the only significant determinant of severe disc degeneration.

Modic changes in endplates of lumbar vertebral bodies: prevalence and association with low back and sciatic pain among middle-aged male workers.

STUDY DESIGN: Cross-sectional comparison of self-reported low back pain (LBP) symptoms and Modic findings on magnetic resonance imaging (MRI). OBJECTIVES: To investigate associations of frequency and intensity of LBP and sciatic pain with Modic changes in a sample of middle-aged male workers with or without whole-body vibration exposure. SUMMARY OF BACKGROUND DATA: Vertebral endplate changes are bone marrow lesions visible on MRI and are assumed to be associated with degenerative intervertebral disc disease. Associations of these so-called Modic changes with clinical symptoms are controversial. Furthermore, most of these studies have been performed in selected series of patients. METHODS: A total of 228 middle-aged male workers (159 train engineers and 69 sedentary controls) from northern Finland underwent sagittal T1 and T2-weighted MRI. Both endplates of 1140 lumbar interspaces were graded for type and extent of Modic changes. Logistic regression was used to analyze associations of pain variables with Modic changes. RESULTS: Train engineers had on the average higher sciatic pain scores than the sedentary controls, but the prevalence of Modic changes was similar in both occupational groups. Altogether, 178 Modic changes in 128 subjects were recorded: 30% were type I, 66% type II, and 4% both types I and II. Eighty percent of changes occurred at L4-L5 or L5-S1. Modic changes at L5-S1 showed significant association with pain symptoms with increased frequency of LBP (odds ratio [OR] 2.28; 95% confidence interval [CI] 1.44-3.15) and sciatica episodes (OR 1.44; 95% CI 1.01-1.89), and with higher LBP visual analog scores during the past week (OR 1.36; 95% CI 1.06-1.70). Type I lesions and extensive lesions in particular were closely associated with pain. CONCLUSIONS: Modic changes at L5-S1 and Modic type I lesions are more likely to be associated with pain symptoms than other types of Modic changes or changes located at other lumbar levels.

Occupational and genetic risk factors associated with intervertebral disc disease.

STUDY DESIGN: Cross-sectional epidemiologic study. OBJECTIVE: To evaluate the interaction between known genetic risk factors and whole-body vibration for symptomatic intervertebral disc disease (IDD) in an occupational sample. SUMMARY OF BACKGROUND DATA: Risk factors of IDD include, among others, whole-body vibration and heredity. In this study, the importance of a set of known genetic risk factors and whole-body vibration was evaluated in an occupational sample of train engineers and sedentary controls. METHODS: Eleven variations in 8 genes (COL9A2, COL9A3, COL11A2, IL1A, IL1B, IL6, MMP-3, and VDR) were genotyped in 150 male train engineers with an average of 21-year exposure to whole-body vibration and 61 male paper mill workers with no exposure to vibration. Subjects were classified into IDD-phenotype and asymptomatic groups, based on the latent class analysis. RESULTS: The number of individuals belonging to the IDD-phenotype was significantly higher among train engineers (42% of train engineers vs. 17.5% of sedentary workers; P = 0.005). IL1A -889T allele represented a significant risk factor for the IDD-phenotype both in the single marker allelic association test (P = 0.043) and in the logistic regression analysis (P = 0.01). None of the other allele markers was significantly associated with symptoms when analyzed independently. However, for all the SNP markers considered, whole-body vibration represents a nominally significant risk factor. CONCLUSION: The results suggest that whole-body vibration is a risk factor for symptomatic IDD. Moreover, whole-body vibration had an additive effect with genetic risk factors increasing the likelihood of belonging to the IDD-phenotype group. Of the independent genetic markers, IL1A -889T allele had strongest association with IDD-phenotype.

Control of the lumbar neutral zone decreases low back pain and improves self-evaluated work ability: a 12-month randomized controlled study.

STUDY DESIGN: A randomized controlled study with 12 months intervention. OBJECTIVE: To study the effectiveness of a training intervention with emphases on the control of lumbar neutral zone (NZ) and behavior modeling as secondary prevention of low back pain (LBP) and disability. SUMMARY OF BACKGROUND DATA: Improving the control of lumbar NZ and enhancing muscle activation patterns ensuring spinal stability have been proposed as means for secondary prevention of LBP and disability. In addition, cognitive behavior interventions have been shown to lower the risk of recurrence of LBP and long-term disability. METHODS: Middle-aged working men with recent LBP but without severe disability were randomly allocated to either a training (TG, n = 52) or control group (CG, n = 54). The aim was to exercise twice a week for 12 months, once guided and once independently. The outcome measures were the changes in intensity of LBP, disability, self-evaluated future work ability, and neuromuscular fitness. RESULTS: The intensity of LBP decreased significantly more (39%) in the TG than in CG at 12 months. The proportion of subjects with negative expectations about their future work ability decreased in both groups at 6 and 12 months; however, the proportion was significantly bigger in TG compared with CG (P = 0.028). There effects on disability indexes and fitness were not statistically significant. CONCLUSIONS: Controlling lumbar NZ is a specific form of exercise and daily self-care with potential for prevention of recurrent nonspecific LBP and disability among middle aged working men.