Presence Of Disc Degeneration Research Articles

No evidence of association between either Modic change or disc degeneration and five circulating inflammatory proteins.

Intervertebral disc degeneration and Modic change are the main spinal structural changes associated with chronic low back pain (LBP). Both conditions are thought to manifest local inflammation and if inflammatory proteins translocate to the blood circulation could be detected systemically. The work here assesses whether the presence of disc degeneration is associated with detectable blood level changes of five inflammatory markers and whether chronic LBP is associated with these changes. Two hundred and forty TwinsUK cohort participants with both MRI disc degeneration grade and Modic change extent, and IL-6, IL-8, IL-8 TNF, and CX3CL1 protein blood concentration measurements were included in this work. Linear mixed effects models were used to test the association of blood cytokine concentration with disc degeneration score and Modic change volumetric score. Association of chronic LBP status from questionnaires with disc degeneration, Modic change, and cytokine blood concentration was also tested. No statistically significant association between disc degeneration or Modic change with cytokine blood concentration was found. Instead, regression analysis pointed strong association between cytokine blood concentration with body mass index for IL-6 and with age for IL-6 and TNF. Mild association was found between IL-8 blood concentration and body mass index. Additionally, LBP status was associated with Modic change volumetric score but not associated with any cytokine concentration. We found no evidence that Modic change and disc degeneration are able to produce changes in tested blood cytokine concentration. However, age and body mass index have strong influence on cytokine concentration and both are associated with the conditions studied which may confound associations found in the literature. It is then unlikely that cytokines produced in the disc or vertebral bone marrow induce chronic LBP.

Some magnetic resonance imaging findings may predict future low back pain and disability: a systematic review

Do magnetic resonance imaging (MRI) findings predict future low back pain (LBP), associated disability and global recovery in people with current LBP? Do MRI findings predict these outcomes in people with no current LBP? Do MRI findings predict these outcomes in a mixed sample of people with and without current LBP? This review is an update of a previous systematic review investigating the relationship between lumbar spine MRI findings and future LBP. People with or without LBP with lumbar MRI scans. MRI findings, pain and disability. Of the included studies, 28 reported on participants with current LBP, eight reported on participants with no LBP and four reported on a mixed sample. Most results were based on single studies and did not demonstrate clear relationships between MRI findings and future LBP. In populations with current LBP, pooling demonstrated that the presence of Modic type 1 changes alone or Modic type 1 and 2 changes were associated with slightly worse pain or disability outcomes in the short term, and the presence of disc degeneration was associated with worse pain and disability outcomes in the long term. In populations with current LBP, pooling demonstrated no evidence of an association between the presence of nerve root compression and disability outcomes in the short term, and no evidence of an association between the presence of disc height reduction, disc herniation, spinal stenosis, high-intensity zone and clinical outcomes in the long term. In populations with no LBP, pooling demonstrated that the presence of disc degeneration may increase the likelihood of experiencing pain in the long term. In mixed populations, no pooling was possible; however, single studies demonstrated that Modic type 1, 2 or 3 changes and disc herniation were each associated with worse pain in the long term. The results suggest that some MRI findings may have weak associations with future LBP; however, larger high-quality studies are needed to resolve uncertainty. PROSPERO CRD42021252919.

Radiologic risk factors associated with development of myelopathy in patients with ossification of the posterior longitudinal ligament of the cervical spine.

Retrospective Cohort Study OBJECTIVE: Myelopathy following ossification of the posterior longitudinal ligament (OPLL) is one of the devastating clinical features in these patients, while we still know little about which factors are associated with development of myelopathy. We evaluated the difference of radiologic measurements between OPLL patients with or without myelopathy and searched for the clinical significance with emphasis on the impact of dynamic motion. 305 patients diagnosed of OPLL were enrolled for retrospective review. They were divided into two groups according to the coexistence of radiographic evidence of myelopathy. Demographic data as well as radiologic measures including the presence of disc degeneration (DD), anterior-posterior diameter (APD) of central canal, canal compromise (CC) ratio, global and segmental range of motion (gROM and sROM), OPLL type (morphologic classification) and K-line were collected. APD (odds ratio (OR); 0.411), CC ratio (OR; 1.100) and sROM (OR; 1.371) were significantly associated with the presence of myelopathy in the multivariate analysis. While the statistically significant factors were same in OPLLs with CC larger than 50%, presence of DD (OR; 4.509) and sROM (OR; 1.295) were significantly associated with myelopathy but not the CC itself in OPLLs with CC smaller than 50%. We discovered that the APD, CC ratio and sROM had significant association with development of myelopathy in OPLLs. And the presence of dynamic factors had significant association with myelopathy in OPLLs with smaller CC ratios. This observation and its clinical significance on development of myelopathy might enhance our understanding of OPLL.

The lumbar intervertebral discs in males and females: measures, correlation, modeling

Annotation. The use of math algorithms for calculating the anatomical and functional parameters of the organs and systems based on somatometric parameters and allows to individualize and quantify the indicators of the norm. In order to build mathematical models to calculate the size of the lumbar spine intervertebral discs somatometry of almost healthy 80 girls and women aged 16-26 years and 74 juniors and men aged 17-28 years was performed. As well as magnetic resonance imaging of the lumbar spine was used to obtain the MR-images in the axial, sagittal and frontal planes in the T2-TSE mode and to perform MR-morphometry by using the DICOM image processing program. The correlation analysis and estimation of interrelations of somatometric parameters with partial linear sizes of intervertebral disks, the sum of the disks’ sizes and relative somato-disk rate are carried out. Body weight was found to have strong correlations with relative somato-disc rate (mean correlation coefficients for L1-L5 intervertebral discs were 0.803 and 0.821 in women and men, respectively) and weak and very weak correlations with partial disc sizes. When constructing the regression model, as an intermediate stage of the calculation, the somato-disk rate (the ratio of mass-growth coefficient to the sum of the sizes of the intervertebral disc) was used. The simulation of the three sizes’ sum of intervertebral discs L1-L5 segments was ultimately based on weight and body length (coefficient of determination R2 is from 80.4% for the sum of the intervertebral discs L1-L2 in girls and women and boys and men, up to 89.7% for the sum of the size of the intervertebral disc L4-L5 in girls and women). Verification of the obtained mathematical models showed a discrepancy between the calculated and measured indicators of the sums of intervertebral disc sizes in the presence of disc degeneration. The used mathematical algorithm for calculating individualized indicators of linear dimensions of lumbar intervertebral discs on the base of somatometric parameters allowed to determine the absence of objective quantitative changes in unchanged intervertebral discs and avoid overdiagnosis.

Phenotype profiling of Modic changes of the lumbar spine and its association with other MRI phenotypes: a large-scale population-based study

Background contextModic changes (MC) are associated with low back pain. They represent vertebral endplate and adjacent vertebral marrow changes on magnetic resonance imaging (MRI), classified into three types. Because of small sample sizes, patient cohorts, and limited phenotype assessment, the morphology and involvement of MC and their association with other spinal phenotypes remain speculative. PurposeWe addressed and proposed a phenotypic profiling of MC and their relationship with lumbar MRI phenotypes in a large-scale population-based study. Study design/settingA cross-sectional study of the Hong Kong Disc Degeneration Cohort. Patient sampleThe study population consisted of 1,546 Southern Chinese volunteers. Outcome measuresTopographical and morphological dimensions of MC, presence of disc degeneration (DD) and displacement, and Schmorl nodes were evaluated. MethodsAxial T1-weighted and sagittal T2-weighted MRIs (3T) were assessed. ResultsFemales were 62.4% (mean age, 49 years). The overall prevalence of MC was 21.9% (6.3% Type I and 15.5% Type II). Of all MC, 76% were located at the two lowest lumbar levels. Modic changes at the two lowest lumbar levels were more commonly located laterally (p<.001), less commonly anteriorly (p<.001), and were more extensive horizontally (p=.006) but not in vertical height compared with the upper levels. Type I MC were less common in the anterior part (p=.022), larger in size (height p=.004), and affected more likely the whole horizontal plane (p=.016) than Type II MC. Modic changes were associated with disc displacement, Schmorl nodes, and DD at the affected level (all p<.001), and the strength of association increased with the size of the lesion. Type I MC were associated more strongly with disc displacement (p=.008) and DD (p=.022) than Type II MC. ConclusionsOur large-scale MRI study is the first to definitely note that MC were size- and type-dependently significantly associated with disc pathology and endplate abnormalities. Our phenotype profiling of MC may have clinical utility.

Associated Factors of Intervertebral Disc Degeneration—Current Results from a Population-Based Cohort: The Wakayama Spine Study

Introduction Intervertebral disc degeneration (DD) is thought to be the first step of degenerative spinal changes. Furthermore, DD is considered to be one of the causes of several symptoms including low back pain (LBP). Although previous studies have investigated the association between DD and LBP as well as risk factors of DD, many of them are still controversial mainly because of the selection bias for the cohort. The purposes of this study were (1) to examine the association between the presence of DD and low back pain, and (2) to examine the risk factors related to DD (age, gender, body mass index [BMI], hyperlipidemia, diabetes mellitus [DM], peripheral artery disease [PAD], and smoking) using a large scale population-based cohort. Materials and Methods This was a cross-sectional study of the base-line data from the population-based cohort of Wakayama, western part of Japan, comprising 975 (men, 324; women, 651; mean age 66.4 years) of 1,011 participants (age, 21-97 years). The participants were subjected to the entire spine MRI and the lumbar intervertebral disc was evaluated according to the Pfirrmann classification system (1-3 = nondegeneration; 4, 5 = degeneration). Multiple logistic regression analysis was used to estimate the association between DD and low back pain after adjustment for age, gender, and BMI. Besides this, we analyzed the association between the presence of DD and the potential risk factors: age, gender, BMI, hyperlipidemia, diabetes mellitus (DM), peripheral artery disease (PAD), and smoking. Results The presence of DD was significantly associated with low back pain. The multiple logistic regression analysis indicated that older age, obesity, and hyperlipidemia were significant related factors of DD. Gender, DM, PAD, and smoking were not significantly related with DD in our cohort. Conclusion The current data provide the foundation for elucidating the causes and mechanisms of DD. However, there is a limitation concerning a temporal relationship between exposure and outcome due to the nature of cross-sectional study design. The second survey of the cohort, which is now ongoing, will provide important information in the near future. Disclosure of Interest None declared Reference Teraguchi M, Yoshimura N, Hashizume H, et al. Prevalence and distribution of intervertebral disc degeneration over the entire spine in a population-based cohort: the Wakayama Spine Study. Osteoarthritis Cartilage 2014;22(1):104–110

Hypertension is Independently Associated with Lumbar Disc Degeneration: A Large-Scale Population-Based Study

Introduction Low back pain (LBP) is the most disabling condition in the world. Lumbar intervertebral disc degeneration is one of the risk factors for LBP. In particular, specific clinically relevant phenotypes of degeneration, such as moderate and severe degenerative changes, have been noted to increase the risk of the development of low back pain. Although progressive age, abnormal biomechanics, and genetics play a role in the development of disc degeneration, cardiovascular risk factors (e.g., age, smoking, obesity, etc.) have also been suggested to be determinants. Hypertension, manifesting as elevated systolic and/or diastolic blood pressure, is a factor related to cardiovascular disease; however, its role in the development of disc degeneration among a population remains speculative. As such, this large-scale population-based study addressed the association of blood pressure in relation to lumbar disc degeneration. Materials and Methods This was a cross-sectional study of the Hong Kong Disc Degeneration-Cardiovascular Cohort, currently composed of approximately 1,800 Southern Chinese volunteers. At the time of analyses, there were 1,261 subjects (36.6 males; 63.4% females) with a mean age of 52.4 years (range: 30-89; SD: ± 6.3 years). Serum lipid profile, glucose, ESR, and other blood parameters were assessed. Anthropomorphic and lifestyle/environmental (e.g., smoking, exercise, occupation) measurements as well as pain profiles were obtained of all subjects. Systolic and diastolic blood pressure assessment was conducted on three occasions. Hypertension was defined as systolic blood pressure of ≥ 140 mm Hg and/or diastolic pressure of ≥ 90 mm Hg. Medication use was accounted. Each subject had undergone T2-weighted MRI of the lumbar spine from L1-S1. Disc degeneration of each lumbar disc was assessed by the Schneiderman et al radiographic criteria. A summated degenerative disc disease (DDD) score was obtained of the entire lumbar spine. DDD score was used to denote subjects with normal, mild, medium, moderate, and severe degrees of disc degeneration. A DDD score of 5 of greater was regarded as a moderate/severe imaging phenotype of disc degeneration. Additional spinal imaging phenotypes (e.g., Modic changes, Schmorl nodes, etc.) were also assessed. Results Overall disc degeneration was present in 79% of all the subjects, most prevalent at L4-L5 (57.9%). Mean DDD score was 3.4 (range: 0-14; SD: ± 2.9 score). Mean systolic and diastolic measurements were 127.0 (range: 81-225; SD: ± 20.1 mm Hg) and 75.6 (range: 41-120; SD: ± 12.3 mm Hg), respectively. Mean systolic/diastolic values were significantly elevated in individuals with the overall presence of disc degeneration (mean: 127.6/76.0 mm Hg) compared with subjects with normal discs (mean: 124.3/73.9 mm Hg) ( p &lt; 0.001). Mean systolic/diastolic values were also significantly greater in individuals with moderate/severe disc degeneration (mean: 131.1/77.6 mm Hg) compared with those that had less severe grades of degeneration (mean: 125.1/74.62 mm Hg) ( p &lt; 0.001). Among the 1,261 subjects, 28% had hypertension. Hypertension was noted in 35.5% of those with moderate/severe disc degeneration compared with 24.5% with less severe degenerative profiles ( p &lt; 0.001). Based on a multivariate regression model adjusting for age, Modic changes, Schmorl nodes, diabetes, ESR, and LBP status, hypertension was significantly related to moderate/severe disc degeneration (OR: 1.51; 95% CI: 1.05-2.17; p = 0.027). Conclusion Based on one of the largest population-based studies addressing imaging, environmental/lifestyle, and cardiovascular risk factors, this study has illustrated for the first time that elevated blood pressure is “independently” associated with different stages of lumbar disc degeneration on MRI. Hypertension increases the likelihood of moderate/severe disc degeneration, a phenotype highly associated with LBP, by 50%. In an age where people are becoming less physically active and more overweight/obese, the prevalence of cardiovascular risk factors will continue to increase. As such, this study raises further awareness of the potential role of vascular disease in a “predictive risk profile model” of lumbar disc degeneration. Disclosure of Interest None declared

Prevalence and distribution of intervertebral disc degeneration over the entire spine in a population-based cohort: the Wakayama Spine Study

The purposes of this study were to investigate the prevalence and distribution of intervertebral disc degeneration (DD) over the entire spine using magnetic resonance imaging (MRI), and to examine the factors and symptoms potentially associated with DD. This study included 975 participants (324 men, mean age of 67.2 years; 651 women, mean age of 66.0 years) with an age range of 21-97 years in the Wakayama Spine Study. DD on MRI was classified into Pfirrmann's system (grades 4 and 5 indicating DD). We assessed the prevalence of DD at each level in the cervical, thoracic, and lumbar regions and the entire spine, and examined DD-associated factors and symptoms. The prevalence of DD over the entire spine was 71% in men and 77% in women aged <50 years, and >90% in both men and women aged >50 years. The prevalence of an intervertebral space with DD was highest at C5/6 (men: 51.5%, women: 46%), T6/7 (men: 32.4%, women: 37.7%), and L4/5 (men: 69.1%, women: 75.8%). Age and obesity were associated with the presence of DD in all regions. Low back pain was associated with the presence of DD in the lumbar region. The current study established the baseline data of DD over the entire spine in a large population of elderly individuals. These data provide the foundation for elucidating the causes and mechanisms of DD.

Total disc replacement for chronic back pain in the presence of disc degeneration

In the search for better surgical treatment of chronic low-back pain (LBP) in the presence of disc degeneration, total disc replacement has received increasing attention in recent years. A possible advantage of total disc replacement compared with fusion is maintained mobility at the operated level, which has been suggested to reduce the chance of adjacent segment degeneration. The aim of this systematic review was to assess the effect of total disc replacement for chronic low-back pain in the presence of lumbar disc degeneration compared with other treatment options in terms of patient-centred improvement, motion preservation and adjacent segment degeneration. A comprehensive search in Cochrane Back Review Group (CBRG) trials register, CENTRAL, MEDLINE, EMBASE, BIOSIS, ISI, and the FDA register was conducted. We also checked the reference lists and performed citation tracking of included studies. We included randomised controlled trials (RCTs) comparing total disc replacement with any other interventionfor degenerative disc disease. We assessed risk of bias per study using the criteria of the CBRG. Quality of evidence was graded according to the GRADE approach. Two review authors independently selected studies and assessed risk of bias of the studies. Results and upper bounds of confidence intervals were compared against predefined clinically relevant differences. We included 40 publications, describing seven unique RCT's. The follow-up of the studies was 24 months, with only one extended to five years. Five studies had a low risk of bias, although there is a risk of bias in the included studies due to sponsoring and absence of any kind of blinding. One study compared disc replacement against rehabilitation and found a statistically significant advantage in favour of surgery, which, however, did not reach the predefined threshold for clinical relevance. Six studies compared disc replacement against fusion and found that the mean improvement in VAS back pain was 5.2 mm (of 100 mm) higher (two studies, 676 patients; 95% confidence interval (CI) 0.18 to 10.26) with a low quality of evidence while from the same studies leg pain showed no difference. The improvement of Oswestry score at 24 months in the disc replacement group was 4.27 points more than in the fusion group (five studies; 1207 patients; 95% CI 1.85 to 6.68) with a low quality of evidence. Both upper bounds of the confidence intervals for VAS back pain and Oswestry score were below the predefined clinically relevant difference. Choice of control group (circumferential or anterior fusion) did not appear to result in different outcomes. Although statistically significant, the differences between disc replacement and conventional fusion surgery for degenerative disc disease were not beyond the generally accepted clinical important differences with respect to short-term pain relief, disability and Quality of Life. Moreover, these analyses only represent a highly selected population. The primary goal of prevention of adjacent level disease and facet joint degeneration by using total disc replacement, as noted by the manufacturers and distributors, was not properly assessed and not a research question at all. Unfortunately, evidence from observational studies could not be used because of the high risk of bias, while these could have improved external validity assessment of complications in less selected patient groups. Non-randomised studies should however be very clear about patient selection and should incorporate independent, blinded outcome assessment, which was not the case in the excluded studies. Therefore, because we believe that harm and complications may occur after years, we believe that the spine surgery community should be prudent about adopting this technology on a large scale, despite the fact that total disc replacement seems to be effective in treating low-back pain in selected patients, and in the short term is at least equivalent to fusion surgery.

The association of lumbar intervertebral disc degeneration on magnetic resonance imaging with body mass index in overweight and obese adults: A population‐based study

To investigate the association of being overweight or obese with the presence, extent, and severity of lumbar disc degeneration on magnetic resonance imaging (MRI) in adults. A population-based cross-sectional study of 2,599 southern Chinese volunteers was conducted. Subjects underwent radiographic and clinical assessment, and weight and height were measured. Sagittal T2-weighted MRIs of the lumbar spine were obtained. The presence, extent, and severity of disc degeneration and additional radiographic and clinical parameters were assessed. Asian-modified body mass index (BMI) (kg/m(2) ) categories were used. Odds ratios (ORs) and 95% confidence intervals (95% CIs) were calculated. The study included 1,040 men and 1,559 women (mean age 41.9 years). Disc degeneration was noted in 1,890 subjects (72.7%). BMI was significantly higher in subjects with disc degeneration (mean 23.3 kg/m(2) ) than in subjects without degeneration (mean 21.7 kg/m(2) ) (P < 0.001). A significant increase in the number of degenerated levels (P < 0.001), global severity of disc degeneration (P < 0.001), and end-stage disc degeneration with disc space narrowing (P < 0.001) was noted with elevated BMI, in particular in overweight and obese subjects. In the adjusted multivariate logistic regression model, there was a positive linear trend (r(2) = 0.99) between BMI and the overall presence of disc degeneration in overweight (OR 1.30 [95% CI 1.03-1.62]) and obese (OR 1.79 [95% CI 1.17-2.74]) subjects. End-stage disc degeneration with disc space narrowing was significantly more pronounced in obese subjects (adjusted OR 1.72 [95% CI 1.23-2.41] [reference normal weight]). Our findings, in one of the largest studies to systematically assess lumbar disc degeneration on MRI, indicated a significant association between the presence, extent, and global severity of disc degeneration with weight in overweight and obese adults.

Degenerative Magnetic Resonance Imaging Changes in Patients With Chronic Low Back Pain

Systematic review. To systematically search for critically appraise and summarize studies that (1) evaluated the association between degenerative magnetic resonance imaging (MRI) changes and chronic low back pain (CLBP) and (2) compared surgical and nonsurgical treatment of these degenerative MRI changes. The role of routine MRI in patients with CLBP is unclear. It is also uncertain whether or not surgical treatment of degenerative MRI changes results in alleviation of back pain. Systematic literature searches were conducted in PubMed for studies published through March 1, 2011. To evaluate whether MRI degenerative changes are associated with CLBP, studies that were designed to compare the prevalence of MRI changes among subjects with and without CLBP were sought. The prevalence odds ratio was used to compare the odds of degenerative MRI findings in subjects with CLBP to the odds of such findings among those without CLBP. To evaluate whether surgical treatment of degenerative MRI changes is associated with different outcomes compared with nonsurgical treatment, comparative studies were sought. The GRADE system as applied to describe the strength of the overall body of evidence. Regarding the association of degenerative changes on MRI and CLBP, five studies were included, all of which were cross-sectional in design. On the basis of these studies, a statistically significant association was found in all but one study regarding the presence of disc degeneration and CLBP (odds ratio range: 1.8-2.8). The overall strength of evidence across studies was considered to be insufficient, however. No comparative studies of surgical versus nonsurgical treatment of degenerative MRI changes were identified. Although there may be an association between degenerative MRI changes and CLBP, it is unknown if these estimates accurately represent the association given the quality of included studies, lack of a direct link between degenerative MRI changes and CLBP, and heterogeneity across studies. Thus, a strong recommendation against the routine use of MRI for CLBP evaluation is made. Since there are no data evaluating the efficacy of the surgical treatment of degenerative MRI changes, a strong recommendation is made against the surgical treatment of CLBP based solely upon degenerative MRI changes. There is insuffi cient evidence to support the routine use of MRI in patients with CLBP. Strong Surgical treatment of CLBP based exclusively on MRI fi ndings of degenerative changes is not recommended. Strong.

MRI findings are more common in selected patients with acute low back pain than controls?

The purpose of this study is to investigate if lumbar disc pathology identified on MRI scans is more common in patients with acute, likely discogenic, low back pain than matched controls. We compared rates of MRI findings between 30 cases with low back pain and 30 pain-free controls. Cases were patients presenting for care with likely discogenic low back pain (demonstrated centralisation with repeated movement testing), of moderate intensity and with minimal past history of back pain. Controls were matched for age, gender and past history of back pain. Cases and controls underwent MRI scanning which was read for the presence of a range of MRI findings by two blinded assessors. The presence of disc degeneration, modic changes and disc herniation significantly altered the odds of a participant being a case or control. For example subjects were 5.2 times more likely to be a case than a control when disc degeneration grade of ≥3 was present, and 6.0 times more likely with modic changes. The presence of a high-intensity zone or annular tear was found to significantly alter odds for one assessor but not the other assessor. MRI findings including disc degeneration, modic changes and herniation are more common in selected people with current acute (likely discogenic) low back pain than in controls without current low back pain. Further investigation of the value of MRI findings as prognostic factors and as treatment effect modifiers is required to assess the potential clinical importance of these findings.

Factors Associated With the Thickness of the Ligamentum Flavum

Ligamentum flavum (LF) thickness was measured by using lumbar magnetic resonance imaging in patients with low back or leg pain. This study investigated whether LF thickening is due to hypertrophy or buckling related to disc degeneration and examined the correlations between the thickness of the LF and age, sex, body mass index (BMI), degree of pain, lumbar spinal stenosis (LSS), and disc herniation. "LF thickness" and "LF hypertrophy" are used interchangeably in the literature, although they are not necessarily the same thing. Thickness may increase by buckling without a change in the mass of the LF, and whether LF thickening is due to tissue hypertrophy or buckling remains controversial. The thickness of 896 LFs at the L2-L3, L3-L4, L4-L5, and L5-S1 levels of 224 (mean age, 47.8 ± 16.7 yrs) patients was measured prospectively on axial T1-weighed magnetic resonance images, obtained at the facet joint level. The presence of disc degeneration, spinal stenosis, and disc herniation was evaluated. At all of the levels investigated, LF thickness was significantly greater in patients with grades IV to V degeneration compared with the patients with grades I to III degeneration (P < 0.05). LF thickness at all levels increased significantly with age (P < 0.05). Sex and the degree of pain were not correlated with the thickness of the LF. Patients with a BMI of 25 kg/m or greater had the thickest LF at the L3-L4 level (P < 0.01). LF thickness was significantly greater at the L2-L3, L3-L4, and L4-L5 levels in subjects with LSS and significantly greater at all levels in subjects with disc herniation (P < 0.05). Thickening of the LF is correlated with disc degeneration, aging, BMI, LSS, spinal level, and disc herniation. The authors concluded that thickening of the LF is due to buckling of the LF into the spinal canal secondary to disc degeneration more than to LF hypertrophy. Sex and the degree of pain were not correlated with the thickness of the LF.

Adjacent Segment Degeneration After Lumbar Spinal Fusion: The Impact of Anterior Column Support

Randomized controlled trial. To analyze long-term adjacent segment degeneration (ASD) after lumbar fusion on magnetic resonance imaging and compare randomization groups with and without anterior column support. ASD can be a long-term complication after fusion. The prevalence and the cause of ASD are not well documented, but ASD are one of the main arguments for introducing the use of motion-preserving techniques as an alternative to fusion. Anterior lumbar interbody fusion combined with posterolateral lumbar fusion (ALIF+PLF) has been proved superior to posterolateral fusion alone regarding outcome and cost-effectiveness. Between 1996 and 1999, 148 patients with severe chronic low back pain were randomly selected for ALIF+PLF or for PLF alone. Ninety-five patients participated. ASD was examined on magnetic resonance imaging with regard to disc degeneration, disc herniation, stenosis, and endplate changes. Disc heights on radiographs taken at index surgery and at long-term follow-up were compared. Outcome was assessed by validated questionnaires. The follow-up rate was 76%. ASD was similar between randomization groups. In the total cohort, endplate changes were seen in 26% of the participants and correlated significantly with the presence of disc degeneration and disc herniation. Disc degeneration and dorsal disc herniation were the parameters registered most frequently and were significantly more pronounced at the first adjacent level than at the second and the third adjacent levels. Patients without disc height reduction over time were significantly younger than patients with disc height reduction. Disc degeneration and stenosis correlated significantly with outcome at the first adjacent level. The cause of the superior outcome in the group with anterior support is still unclear. Compared with the findings reported in the literature, the prevalence of ASD is likely to be in concordance with the expected changes in a nonoperated symptomatic population and therefore not accelerated by fusion.

Análise radiológica da degeneração discal experimental em coelhos

OBJETIVO: Validar a avaliação radiográfica da degeneração discal experimental em coelhos. MÉTODOS: Os discos intervertebrais lombares de coelhos New Zealand foram puncionados três vezes com uma agulha 18G com profundidade limitada de 5mm, através de abordagem lateral. Foram realizadas radiografias seriadas pré e pós-operatórias imediatas, e depois de quatro, oito e 12 semanas do procedimento, com posterior análise da altura discal, formação de osteófito, esclerose da placa vertebral e presença de degeneração discal. A análise estatística dos dados foi validada pelo coeficiente de concordância Kappa, com intervalo de confiança (IC) de 95%. RESULTADOS: Observou-se diminuição significativa do espaço discal nas radiografias em AP após 12 semanas de pós-operatório, com Kappa = 0,489 para IC 95% (0,25-0,72) com p < 0,001. Os sinais radiográficos de degeneração discal também apresentaram valor de Kappa = 0,63 para IC 95% (0,39-0,86) com p < 0,001. Os demais critérios avaliados tiveram resultados positivos, porém, com menor valor de Kappa. CONCLUSÃO: O modelo de degeneração discal em coelhos proposto neste estudo mostrou-se factível, com correlação radiológica positiva entre as imagens pré e pós-operatórias, validando a possibilidade de indução de degeneração discal nesse modelo animal para futuros estudos.

RADIOLOGICAL ANALYSIS OF EXPERIMENTAL DISC DEGENERATION IN RABBITS

Objective: To validate radiographic evaluation of a rabbit model for disc degeneration. Methods: Lumbar intervertebral discs of New Zealand rabbits were stabbed three times with a 18G needle at a limited depth of 5mm, through lateral approach. Serial radiographic images were taken on the early pre-and postoperative periods, and after four, eight and 12 weeks of the procedure, with subsequent analysis of disc height, osteophyte formation, endplate sclerosis, and presence of disc degeneration. The statistical analysis of data was validated by the Kappa coefficient, with a confidence interval (CI) of 95%. Results: A significant reduction of disc space was found on AP X-ray images after 12 postoperative weeks, with Kappa = 0.489 for CI 95% (0.25-0.72) with p < 0.001. X-ray signs of disc degeneration also presented Kappa = 0.63 for CI 95% (0.39-0.86) with p < 0.001. The remaining assessed criteria showed positive results, but with a lower Kappa value. Conclusion: The disc degeneration model using rabbits as proposed in this study was shown to be feasible, with positive X-ray correlation between pre- and postoperative images, validating the potential to induce disc degeneration in this animal model for future studies.

In Vitro Disc Pressure Profiles Below Scoliosis Fusion Constructs

Biomechanical human cadaveric study comparing straight and scoliotic spines with healthy and degenerated L4/5 discs. To describe the biomechanical environment of discs under various spinal alignments by measuring the coronal intradiscal pressure profiles. Abnormal loading of the lumbar discs in the concavity of scoliotic curves may accelerate disc degeneration, which may be related to pain. Eight intact human cadaver spines (T1-S1; mean donor age 47 years old) underwent radiographs, DEXA, and MRI and were graded for disc degeneration. Each specimen was instrumented in a normal (straight coronal) spinal alignment from T4-L4. Intradiscal pressure profiles for the L4/5 disc and resultant moments were obtained under axial follower loads up to 1500 N. Testing was repeated for bilateral 3-cm decompensation. Posterior instrumentation was used to induce scoliosis (thoracic and lumbar curve average = 25 degrees, fractional lumbosacral curve average = 5 degrees), and testing was repeated for all load states. MRI found 4 healthy (grade I and II) and 4 degenerated (grade III to V) L4/5 discs. Scoliosis and decompensation significantly increased coronal moments (P < 0.003). Disc pressures increased linearly with greater applied loads for all specimens. Healthy L4/5 discs exhibited uniform pressure profiles with normal spinal alignment and minimal effect with simulated scoliosis or decompensation. For degenerated discs, there was a relative pressure profile depression in the nucleus relative to the anulus region; with spinal malalignment, either due to scoliotic curvature, decompensation, or both, there was disc pressure profile asymmetry. The ratio of maximum intradiscal pressure at the concavity relative to the convexity was 1.1 (range, 1.0-1.2) for healthy discs and 3.6 (range, 2.2-4.4) for degenerated discs in the scoliotic specimens (P = 0.008). Disc pressure profilometry below long spinal constructs found asymmetric loading with the greatest loads at the concave inner anulus, especially in the presence of disc degeneration, scoliosis, and decompensation. For the degenerated cases, there was substantial disc pressure profile asymmetry despite only mildly severe scoliotic curvatures. These results suggest that scoliosis surgeons should minimize end-vertebra tilt, maximize lumbar curve, and balance correction at the time of surgical intervention. These results combined with prior animal studies suggest a compounding effect of asymmetric loading and progression of disc degeneration.

Association between decreased disc signal intensity in preoperative T2-weighted MRI and a 5-year outcome after lumbar minimally invasive discectomy.

A total of 39 patients who had undergone microdiscectomy or percutaneous nucleotomy for lumbar disc herniation were examined after a follow-up of 5 years. The overall outcome was satisfactory in 80% of the patients treated, and only 1 (3%) patient had been reoperated during the follow-up. Clinical signs and symptoms of lumbar instability were detected in 10 (26%) patients. All these 39 patients had been examined with lumbar magnetic resonance imaging (MRI) on the day preceding the operation; the presence of disc degeneration was graded as severe, mild or non-existent depending on the visual brightness of the discs on T2-weighted images, as compared to the signal intensity of the lumbar vertebrae. None of the 12 patients with no preoperative disc degeneration in MRI suffered from postoperative clinical signs and symptoms of instability as compared to 10 (37%) of the 27 patients with mild or severe disc degeneration suffering from instability (p = 0.04). Thus, the results of the present study imply that the grade of the disc degeneration in preoperative T2-weighted MR images significantly predicted the occurrence of postoperative clinical instability.

The Role of Facet Joint Tropism and Facet Angle in Disc Degeneration

In this study, the relationship between facet geometry (joint angle and tropism) and disc degeneration was analyzed. Magnetic resonance imaging and computed tomographic scans of 46 subjects less than 50 years of age were evaluated. Magnetic resonance imaging was used to determine disc degeneration, and computed tomography was used to measure facet joint angles and determine tropism. Subjects with tropism had a significantly higher prevalence of disc degeneration at all three lumbar levels examined (L3-4, L4-5, L5-S1). The average facet angles increased from L3-4 to L4-5 and further to the L5-S1 level. There was no statistically significant relationship between the magnitude of the angle and the presence of disc degeneration at any of the three levels. It was concluded that the risk of disc degeneration is increased in the presence of facet joint tropism.

Discs Degenerate Before Facets

The purpose of this study was to determine the relationship between facet joint osteoarthritis and disc degeneration in subjects in whom both MRI and CT scans had been obtained. The MRI scans were used to determine disc degeneration, the CT scans to determine facet joint osteoarthritis. It was hypothesized that disc degeneration would sometimes occur without the presence of facet joint osteoarthritis, but that facet joint osteoarthritis would only occur in the presence of disc degeneration. Sixty-eight sets of scans were included and 330 discs and 390 facet joints were evaluated. There were 144 degenerated discs and 41 levels with facet osteoarthritis. Disc degeneration without facet osteoarthritis was found at 108 levels, while all but one of 41 levels with facet degeneration also had disc degeneration. That one exception occurred in a patient with advanced Paget's disease. Disc degeneration and facet osteoarthritis both were found to increase with increasing age. There was no difference between women and men. Degeneration at the L4-5 and L5-S1 levels was significantly more prevalent than at the L3-4 levels, while degeneration at the L3-4 level was significantly more common than at the L1-2 and L2-3 levels. We conclude that disc degeneration occurs before facet joint osteoarthritis, which may be secondary to mechanical changes in the loading of the facet joints.