A systematic review evaluating the association of atherosclerosis and lumbar degenerative disc disease

Introduction

Lumbar disc herniation (LDH) and disc degeneration (DD) are associated with low back pain (LBP) and sciatica, which are common health problems. Emerging evidence suggests a link between vascular health, specifically abdominal aortic calcification (AAC) and systemic lipid profiles, and these spinal conditions.

Research question

This study investigates the associations between AAC, systemic lipid profiles, lumbar Modic Changes (MC), DD/LDH, and the occurrence of LBP or sciatica.

Material and methods

A literature search was performed (up to August 2023) in PubMed, Embase, Web of Science, Emcare, Cochrane Library, and Academic Search Premier utilizing a sensitive search strategy. Studies were chosen based on predefined criteria and assessed for bias using an adapted Cochrane checklist. Specifically, studies exploring the relationship between AAC or lipid status and DD/LDH and/or LBP/Sciatica were included.

Results

Twenty-seven studies were included. Eight studies assessed the association between atherosclerosis or lipid status and clinical LBP/sciatica, with four showing a positive association between AAC/lumbar artery stenosis and these conditions. Twenty-one studies assessed atherosclerosis and DD/LDH, with seven showing a positive association between AAC and DD/LDH. Eight trials found a positive association between lipid status and DD/LDH, and two trails identified ApoL1 as a biomarker for LDH recovery.

Discussion and conclusion

Evidence supports the hypothesis that inadequate blood supply contributes to disc degeneration, inflammation and clinical symptoms. Both local vascular issues and systemic lipid profiles appear to influence lumbar degeneration, highlighting the need for further research to better understand these relationships and develop preventive and therapeutic strategies.

Association Between Hypercholesterolemia and Lumbar Degenerative Back Pain: A Medicare Expenditure Panel Survey (MEPS) Study

Introduction Hypercholesterolemia is known to be a major contributor to the morbidity associated with cardiovascular disease and has been hypothesized to result in degenerative changes to the spine through atherosclerosis of segmental lumbar vessels. The purpose of this study is to determine the relationship between hypercholesterolemia and degenerative lumbar spine conditions in a U.S. cohort. Methods A total of 30,461 participated in the 2018 Medicare Expenditure Panel Survey (MEPS). Of those, 1,063 subjects responded to whether a diagnosis of lumbar disorders with low back pain was present. Odds ratios (OR) were calculated, and logistic regression analyses were adjusted for demographic, education, occupation, cardiovascular and mental health conditions. Results Of the 1,063 respondents, 455 (43%) reported back pain. Mean age of the respondents was 62.7±16.1. Men and women reported back pain at similar rates (43% vs 45%, p=0.664). Age, race, education level and occupation were similar between those with and without back pain (p>0.05). Those with a diagnosis of depression had higher odds of having back pain (p<0.05). Prevalence of back pain in subjects who responded to the back pain diagnosis item on the survey was 42.6%. On univariate analysis, diagnosis of total cholesterol levels was significantly higher in those with a diagnosis of back pain (OR 1.36, 95% CI [1.20-1.54], p<.0001). Multivariable analysis showed that hypercholesterolemia was independently associated with back pain (adjusted OR 1.32, 95% CI [1.04-1.68], p=0.021) after controlling for covariates. Conclusions In this study, subjects with hypercholesterolemia were 34% more likely to have back pain after controlling for confounders which presents as a recent discovery amongst U.S. populations. Further studies should be performed to investigate the management of hypercholesterolemia in the development and progression of degenerative lumbar back pain.

Association Between Hypercholesterolemia and Neck Pain in a Cross-sectional Population-based Study

STUDY DESIGN

Retrospective cross-sectional analysis.

SUMMARY OF BACKGROUND DATA

Degenerative changes are a major contributor to chronic neck pain. According to the vascular hypothesis of disk disease, atherosclerosis of the segmental arteries contributes to ischemia of the lumbar disks and resulting degenerative changes. Prior studies have demonstrated an association between atherosclerotic risk factors and lumbar degenerative disease. Similarly, atherosclerosis may contribute to cervical disk degeneration. Cardiovascular disease is associated with the development of atherosclerosis, particularly in small vessels to the cervical spine. Hypercholesterolemia is a major contributor to the morbidity associated with cardiovascular disease. This study aims to examine the relationship between hypercholesterolemia and neck pain.

MATERIALS AND METHODS

Analysis was focused on the respondents to neck pain items of the standardized questionnaire. Odds ratios were calculated, and logistic regression analyses adjusted for demographic, education, and mental health conditions.

RESULTS

There were 30,461 participants in the 2018 Medicare Expenditure Panel Survey (MEPS) survey. Of those, 1049 (3.4%) subjects responded to presence of a diagnosis of cervical disorders with neck pain. Mean age of respondents was 62.6±16.1. Overall prevalence of neck pain was 21.1%. Prevalence of neck pain was similar by age, sex, education level, and occupation ( P >0.05 for each). Neck pain was more prevalent in white race and lower total family income ( P <0.05). Current everyday smokers also had higher prevalence of neck pain ( P <0.05). Logistic regression analysis revealed a higher prevalence of neck pain in those with hypercholesterolemia after controlling for relevant covariates (adjusted odds ratio=1.54, 95% CI: 1.08-2.22, P =0.018).

CONCLUSIONS

Subjects with hypercholesterolemia were 54% more likely to have neck pain after controlling for confounders. This suggests that hypercholesterolemia has a role to play in degeneration of the cervical spine. Therefore, prevention and proper management of high cholesterol may curtail the development and progression of degenerative cervical disk disease and thus, neck pain.

A Simple Scale for Screening Lower-Extremity Arterial Disease as a Possible Cause of Low Back Pain: a Cross-sectional Study Among 542 Subjects

BACKGROUND

Epidemiological, imaging, and anatomical studies suggest an association between proximal arterial atherosclerosis and development of low back pain (LBP).

OBJECTIVES

We aimed to define (1) the frequency and (2) factors associated with exercise-induced proximal ischemia (EIPI) in individuals with LBP and (3) develop a clinical screening scale.

DESIGN

Monocentric cross-sectional study.

PARTICIPANTS

All patients with history of ongoing LBP referred to our exercise investigation laboratory for exercise transcutaneous oximetry (ex-tcPO₂) between January 2011 and December 2017 (n = 542; mean age, 65.4 ± 10.9; 83.9% men).

MAIN MEASURES

EIPI was defined as a decrease from rest of oxygen pressure (DROP) below - 15 mmHg on the lumbar and/or buttock probes. Ex-tcPO₂ is a reliable validated tool for diagnosing EIPI in comparison with arteriography and computed tomography angiography. Ex-tcPO₂ was performed on a treadmill until symptom manifestation or exhaustion. Clinical data were collected using interview questionnaires, medical file review, and clinical examination.

KEY RESULTS

EIPI was diagnosed in 282 patients (52%). Age ≤ 70 years (OR, 2.22; 95% CI, 1.35-3.57; p = 0.002), a history of proximal revascularization (OR, 2.64; 95% CI, 1.50-4.65; p = 0.001), use of antiplatelet medication (OR, 1.71; 95% CI, 0.96-3.06; p = 0.069), a relationship between exercise and LBP (OR, 2.61; 95% CI, 1.49-4.57; p = 0.001), and an abnormal ankle to brachial index (OR, 2.87; 95% CI, 1.77-4.66; p < 0.0001) were identified as EIPI predictors. Using these items, we developed a screening scale that showed an area under the receiver operating characteristics curve of .756. At a score of ≥ 3, the sensitivity, specificity, and accuracy for EIPI were 84%, 55%, and 71%, respectively.

CONCLUSIONS

EIPI was common among our patients with LBP undergoing ex-TcPO₂. Our screening scale could help better select the patients who require angiography.

APOE-knockout in rabbits causes loss of cells in nucleus pulposus and enhances the levels of inflammatory catabolic cytokines damaging the intervertebral disc matrix

Rabbits with naturally high levels of cholesterol ester transfer protein (CETP), unlike rodents, have become an interesting animal model for the study of lipid metabolism and atherosclerosis, as they have similarities to humans in lipid metabolism, cardiovascular physiology and susceptibility to develop atherosclerosis. Rodents, such as mice, are not prone to atherosclerosis as they lack the mass and activity of CETP, as a key player in lipoprotein metabolism. Recently, APOE-knockout in rabbits has been shown to promote atherosclerosis and associated premature IVD degeneration that mimic the symptoms of atherosclerosis and structural changes of IVDs in humans. Here we examined whether APOE-knockout promoted IVD degeneration in rabbits is associated with imbalanced inflammatory catabolic activities, as the underlying problem of biological deterioration that mimic the symptoms of advanced IVD degeneration in humans. We analysed in lumbar nucleus pulposus (NP) of APOE-knockout rabbits the cell viabilities and the intracellular levels of inflammatory, catabolic, anti-catabolic and anabolic proteins derogating IVD matrix. Grades of IVD degeneration were evaluated by magnetic resonance imaging. NP cells were isolated from homozygous APOE-knockout and wild-type New Zealand White rabbits of similar age. Three-dimensional cell culture with low-glucose was completed in alginate hydrogel. Cell proliferation and intracellular levels of target proteins were examined by MTT and ELISA assays. Alike human NP cells of different disc degeneration grades, NP cells of APOE-knockout and wild-type rabbits showed significantly different in vivo cell population densities (p<0.0001) and similar in vitro proliferation rates. Furthermore, they showed differences in overexpression of selective inflammatory and catabolic proteins (p<0.0001) similar to those found in human NP cells of different disc degeneration grades, such as IL-1β, TNF-α, ADAMTS-4, ADAMTS-5 and MMP-3. This study showed that premature IVD degeneration in APOE-knockout rabbits was promoted by the accumulation of selective inflammatory catabolic factors that enhanced imbalances between catabolic and anabolic factors mimicking the symptoms of advanced IVD degeneration in humans. Thus, APOE-knockout rabbits could be used as a promising model for therapeutic approaches of degenerative disc disorders.

Iatrogenic Arteriovenous Fistula and Retroperitoneal Hemorrhage After Tapping of Lumbar Pedicle Screws: A Case Report

CASE

A 76-year-old woman underwent L4-L5 posterior lumbar interbody fusion with pedicle screws for lumbar spondylolisthesis. Intraoperative iatrogenic injuries to the right fourth lumbar artery and inferior vena cava occurred, resulting in arteriovenous fistula with extensive retroperitoneal hemorrhage. Endovascular treatment and intraperitoneal drainage were effective in managing retroperitoneal hemorrhage. She showed no sign of organ failure or deep venous thrombosis during her 2-year follow-up.

CONCLUSIONS

We recommend embolization both proximally and distally in the case of lumbar artery injury. Intra-abdominal hypertension secondary to a massive retroperitoneal hematoma should also be considered to prevent abdominal compartment syndrome.

Assessment of Blood Flow Patterns Distal to Aortic Occlusion Using CT in Patients with Resuscitative Endovascular Balloon Occlusion of the Aorta

BACKGROUND

Resuscitative endovascular balloon occlusion of the aorta (REBOA) is used to decrease hemorrhage below the level of aortic occlusion (AO); however, the amount of collateral blood flow below the level of occlusion is unknown. Our aim was to investigate blood flow patterns during complete AO in patients who underwent CT scan after REBOA.

STUDY DESIGN

Between February 2013 and January 2017, patients who received REBOA and underwent CT scan with intravenous contrast during full AO were included. Patients were excluded if they had a CT scan performed with the balloon partially or fully deflated.

RESULTS

Nine patients (8 men) were included; all had blunt trauma. Mean Injury Severity Score (±SD) was 48 ± 8 and mean age was 45 ± 19 years. Four had supra-celiac AO, and 5 had infra-renal AO. Arterial contrast enhancement was noted below the level of AO in all patients, and distal to REBOA sheath placement in 5. Collateralization from arteries above and below the AO was identified in all patients. Contrast extravasation distal to AO was identified in 4 patients, and hematomas in 8. Distal vascular enhancement patterns varied by level of AO and contrast administration site.

CONCLUSIONS

Aortic occlusion appears to dramatically decrease, but does not completely impede, distal perfusion during REBOA due to multiple pathways of collateralization. Active extravasation and hematomas can still be detected in the setting of full AO, with purposefully timed contrast and image acquisition. Blood flow persists below the level of both the AO and in-dwelling sheath. Dynamic flow studies are needed to determine the contribution of AO and sheath placement to distal tissue ischemia.

Infrarenal aortic diameter, aortoiliac bifurcation level and lumbar disc degenerative changes: a cross-sectional MR study

PURPOSE

To examine a possible correlation of infrarenal aortic diameter and aortoiliac bifurcation level with lumbar disc degenerative changes.

METHODS

This was a cross-sectional, single-center retrospective study on lumbar magnetic resonance images of patients with low back pain (n = 496). Lumbar disc degenerative changes were reported on the basis of the Pfirrmann grading system and accordingly, patients were grouped as with grade I-II findings (n = 192), with grade III findings (n = 64) and with grade IV-V findings (n = 240). The groups were matched for sex, body mass index and the history of diabetes mellitus, hypertension, hyperlipidemia and smoking. Infrarenal aortic diameter and aortoiliac bifurcation level were compared between the three groups.

RESULTS

Pairwise comparisons between the three groups of patients with Pfirrmann grades of I-II, III and IV-V revealed significant differences (p < 0.05) in terms of the median infrarenal aortic diameter (17 mm [interquartile range 4], 18 mm [4] and 19 mm [4], respectively) and the median aortoiliac bifurcation level (3 [2], 4 [2] and 5 [3], respectively; the higher the value, the more the caudal displacement). These associations were independent of conventional risk factors of atherosclerosis (including age) and from each other.

CONCLUSIONS

This study showed a significant, direct correlation of the infrarenal aortic diameter and the level of aortoiliac bifurcation with lumbar intervertebral degenerative changes according to the Pfirrmann grading system. The associations were independent of well-known risk factors of atherosclerosis and from each other.

Knockout of Apolipoprotein E in rabbit promotes premature intervertebral disc degeneration: A new in vivo model for therapeutic approaches of spinal disc disorders

Intervertebral disc (IVD) degeneration that accelerates the loss of disc structural and functional integrities is recognized as one of the major factors of chronic back pain. Cardiovascular risk factors, such as deficits of apolipoproteins that elevate the levels of cholesterol and triglycerides, are considered critical for the progress of atherosclerosis; notably in the abdominal aorta and its lumbar branching arteries that supply lumbar vertebrae and IVDs. Obstruction of the lumbar arteries by atherosclerosis is presumed to promote lumbar disc degeneration and low back pain. APOE-knockout rabbits have recently been shown to generate hyperlipidemia with increased levels of cholesterol and triglycerides that mimic the symptoms of atherosclerosis in humans. Here, we analysed IVD degeneration in the lumbar spines of ten homozygous APOE-knockout and four wild-type New Zealand White rabbits of matching age to prove accelerated IVD degeneration in APOE-knockout rabbits, since APOE-knockout rabbits could be a beneficial model for therapeutic approaches of degenerative IVD disorders. Experiments were performed using T1/T2-weighted magnetic resonance imaging, 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide assay, glucose-oxidase assay, enzyme-linked immunosorbent assay, quantitative reverse transcription PCR and western blot. APOE-knockout lumbar spines showed more advanced IVD degeneration, obstructed lumbar arteries and lower enhancement of contrast agent in IVDs. Moreover, lower concentration of glucose, lower number of viable cells and lower concentrations of aggrecan, collagen II and higher concentration of collagen I were detected in APOE-knockout IVDs (p < 0.0001). APOE-knockout in rabbits could induce structurally deteriorating premature IVD degeneration that mimics the symptoms of accelerated IVD degeneration in humans. APOE-knockout rabbits could be used as beneficial model, as they can bypass the standard surgical interventions that are commonly applied in research animals for the induction of enhanced IVD degeneration. Their parallel use in therapeutic approaches of IVD disorders and atherosclerosis could reduce the number of research animals to be used and contribute to the principles of 3Rs (Replacement, Reduction and Refinement).

Atherosclerotic Disease and its Relationship to Lumbar Degenerative Disk Disease, Facet Arthritis, and Stenosis With Computed Tomography Angiography

BACKGROUND

The intervertebral disk is the largest avascular structure in the body. It relies on passive diffusion from arteries at the periphery of the disk for nutrition. Previous studies have suggested a correlation between vascular disease and lumbar degenerative disk disease (DDD), but the association with facet arthritis and stenosis has not been evaluated.

OBJECTIVE

To evaluate the degree of lumbar artery stenosis, aortic atherosclerosis on computed tomography angiography, and its relationship to lumbar DDD, facet arthritis, and spinal canal stenosis.

DESIGN

Retrospective case review.

SETTING

Academic tertiary care hospital.

PARTICIPANTS

Not applicable.

METHODS

A total of 300 lumbar arteries (150 lumbar artery pairs of the first to fifth lumbar arteries) were evaluated on consecutive computed tomography angiography scans. Severity of vascular disease of lumbar arteries was documented as normal, mild, moderate, severe, or occluded. Aortic vascular disease was documented along the posterior wall where the lumbar arteries originate.

MAIN OUTCOME MEASUREMENTS

The relationship between vascular disease with DDD, facet arthritis, and spinal canal stenosis was examined and further evaluated controlling for age.

RESULTS

Lumbar artery and aortic atherosclerosis had a positive relationship with DDD, facet arthritis, and spinal stenosis that was statistically significant (P < .05) even after controlling for age. The correlation coefficient was greatest in the younger age group when looking at lumbar artery vascular disease with DDD (0.73, confidence interval 0.50-0.96, P < .0001) and aortic vascular disease with DDD (0.72, confidence interval 0.49-0.94, P < .0001). The correlation of vascular disease with facet arthritis and stenosis was not strong in the older age group.

CONCLUSION

Atherosclerotic disease of the lumbar arteries and aorta correlated with lumbar DDD, facet arthritis, and spinal canal stenosis after we adjusted for age, although the correlation with facet arthritis and spinal canal stenosis was not as strong in the older age group.

LEVEL OF EVIDENCE

IV.

Modic changes of the lumbar spine: prevalence, risk factors, and association with disc degeneration and low back pain in a large-scale population-based cohort

BACKGROUND CONTEXT

Modic changes (MC) are bone marrow lesions on magnetic resonance imaging (MRI), suggestive of being associated with low back pain (LBP). Data on determinants of MC and their association with disc degeneration and other spinal phenotypes, as well as that of LBP, rely mostly on small-scale patient populations and remain controversial.

PURPOSE

This study addressed the potential determinants of MC and their association with disc degeneration and LBP among Southern Chinese.

STUDY DESIGN/SETTING

A cross-sectional, population-based study was carried out.

PATIENT SAMPLE

This study consisted of 2,449 Southern Chinese volunteers.

METHODS

Sagittal T2-weighted MRIs of the lumbar spine were assessed for the presence of MC and other spinal phenotypes (eg, disc degeneration, disc displacement, Schmorl nodes) in all individuals. Subjects' demographics, occupation, lifestyle, and clinical profiles were assessed.

RESULTS

The overall prevalence of MC was 5.8% (n=141), which increased with advancing age. Modic changes predominantly occurred at the lowest two lumbar levels (83%). In the multivariate analyses, only the presence of disc displacement and a higher disc degeneration score were associated with MC at the upper lumbar levels (L1/L2-L3/L4) (p<.01). The presence of MC at the lowest two lumbar levels (L4/L5-L5/S1) were associated with age, the presence of Schmorl nodes, disc degeneration or displacement, and historical lumbar injury (p<.01). Subjects who were both smokers and overweight or obese had increased likelihood of MC in the lower spine (OR: 2.18; 95% CI: 1.10-4.30). The presence of MC at the lower lumbar levels were associated with historical LBP (OR: 1.93; 95% CI: 1.05-3.54) and with severity and duration of symptoms (p<.05).

CONCLUSIONS

Based on one of the largest MRI studies to assess lumbar MC, we noted that MC were associated with both disc degeneration and the presence and severity of LBP. Determinants and association of MC with disc degeneration and clinical symptoms in the upper versus the lower lumbar spine were different. Our study further stresses the significance of MC as important imaging phenotypes associated with LBP.

Focal compression of the upper left thoracic intersegmental arteries as a potential cause of spinal cord ischemia

BACKGROUND AND PURPOSE

This study was prompted by recurrent angiographic observations of focal stenoses involving the proximal segment of the left upper thoracic intersegmental arteries, a few centimeters distal to their origin. The purpose was to investigate the nature and prevalence of this anomaly.

MATERIALS AND METHODS

The existence of non-ostial thoracic intersegmental artery stenoses was evaluated in 50 angiograms; the contribution of stenosed branches to the anterior spinal artery was recorded. Angiograms performed in 3 patients with right-sided aortas were also reviewed. The topographic relationships of the upper thoracic intersegmental artery with surrounding structures were investigated in 3 cadavers.

RESULTS

Thirty-seven non-ostial stenoses were found in 26 patients (52%), predominantly on the left side (92%), between T3 and T8, most frequently at T4 and T5 (54%). Severe lesions were observed in 10% of cases. Patients with stenoses had fewer detectable anterior radiculomedullary arteries between T3 and T5 (35% versus 54%). Upper intersegmental artery stenoses, documented on the left side of all 3 specimens, appeared to be caused by the recurrent path of these intersegmental arteries related to the leftward position of the thoracic aorta, and by their course around reinforced paramedian longitudinal strands of the endothoracic fascia.

CONCLUSIONS

Upper thoracic intersegmental artery stenoses are frequent. They result from the leftward deviation of the descending aorta and the existence of a fixed point along the course of the intersegmental arteries related to the endothoracic fascia. Because contributors to the spinal vascularization often originate at similar levels, these stenoses may play a role in the susceptibility of the upper and midthoracic spinal cord to ischemia.

Color Doppler ultrasonography of lumbar artery blood flow in patients with low back pain

STUDY DESIGN

Prospective, clinical, noninvasive imaging study.

OBJECTIVE

To quantify normal lumbar artery hemodynamics and develop a reference range and lumbar artery hemodynamics in patients with low back pain.

SUMMARY OF BACKGROUND DATA

Blood supply to the lumbar spinal tissues, intraosseous capillary circulation, and avascular intervertebral discs derives directly from the lumbar arteries. Pathology may affect this blood supply, impact nutrient delivery and contribute to low back pain and disc degeneration. However knowledge of hemodynamic characteristics of lumbar arteries is lacking. This could improve understanding into pathological tissue function and its relation to lumbar spine circulation in back disorders.

METHODS

Sixty-four patients with low back pain and 30 normal controls underwent lumbar spine imaging investigations with color Doppler ultrasonography. Doppler data on blood flow was obtained from arteries at S1 through to L1 bilaterally and angle-corrected peak systolic blood flow velocity (PSV) measured in all vessels. Aortic PSV was used to derive the normalized lumbar artery: Aortic PSV ratio (PSVR) for all subjects' levels L1 to S1 bilaterally.

RESULTS

In both the control and low back pain (LBP) groups blood flow PSV in the lumbar arteries increased incrementally from levels L1 to L4, declined to its lowest values at L5 and rose again at S1. Normalized lumbar artery blood flow PSVR in the LBP group is consistently higher at all levels (L1-S1) than in controls (P < 0.001). At level L5, lumbar artery blood flow PSVR was 46% higher in the LBP group than in controls.

CONCLUSION

Color Doppler ultrasonography can reliably be used as a clinical tool to visualize and quantify blood flow in lumbar arteries of patients with low back disorders. Findings of increased blood flow PSVR in patients are consistent with the well-documented Doppler changes that occur during inflammatory hyperemia.

LEVEL OF EVIDENCE

3.

A population-based study of juvenile disc degeneration and its association with overweight and obesity, low back pain, and diminished functional status

BACKGROUND

Little is known regarding juvenile disc degeneration in individuals with normal spinal alignment. Consequently, the purpose of this study was to assess the prevalence, determinants, and clinical relevance associated with juvenile disc degeneration of the lumbar spine in individuals without spinal deformities.

METHODS

A cross-sectional assessment of disc degeneration in juveniles was performed as part of a population-based study of 1989 Southern Chinese volunteers. Adolescents and young adults from thirteen to twenty years of age were defined as "juveniles." Juvenile subjects with no spinal deformity (n = 83) were stratified into two groups, those with and those without juvenile disc degeneration. Sagittal T2-weighted magnetic resonance images (MRI) were evaluated for the presence and extent of disc degeneration as well as other spinal findings. Demographics were assessed and clinical profiles were collected with use of standardized questionnaires.

RESULTS

Juvenile disc degeneration was present in 35% (twenty-nine) of the juveniles without spinal deformity. Disc bulging or extrusion (p < 0.001), high-intensity zones on MRI (p = 0.040), and greater weight (p < 0.001) and height (p = 0.002) were significantly more prevalent in subjects with juvenile disc degeneration. Adjusted multivariate logistic regression modeling demonstrated that Asian-modified body-mass index (BMI) values in the overweight or obese range had a significant association with juvenile disc degeneration (odds ratio = 14.19; 95% confidence interval = 1.44 to 140.40; p = 0.023). Overweight and obese individuals had greater severity of disc degeneration than underweight and normal-weight individuals (p = 0.036). Furthermore, individuals with juvenile disc degeneration had an increased prevalence of low back pain and/or sciatica (p = 0.002), greater low back pain intensity (p < 0.001), diminished social functioning (p = 0.049), and greater physical disability (p < 0.05) than individuals without disc degeneration. The p value of <0.05 for physical disability represents both the physical function (p = 0.006) and the physical component (p = 0.032) of the SF-36.

CONCLUSIONS

This study demonstrated that the presence of juvenile disc degeneration was strongly associated with overweight and obesity, low back pain, increased low back pain intensity, and diminished physical and social functioning. Furthermore, an elevated BMI was significantly associated with increased severity of disc degeneration. This study has public health implications regarding overweight and obesity and the development of lumbar disc disease.

Management of spontaneous and iatrogenic retroperitoneal haemorrhage: conservative management, endovascular intervention or open surgery?

BACKGROUND

Retroperitoneal haematoma is a rare clinical entity with variable aetiology, which is increasing in incidence mainly due to complications related to interventional procedures. There is no general consensus as to the best management plan for patients with retroperitoneal haematoma.

METHODS

A literature review was undertaken using MEDLINE, all relevant papers on retroperitoneal haemorrhage or haematoma were used.

RESULTS

The diagnosis is often delayed as symptoms are nonspecific. Retroperitoneal haematoma should be suspected in patients with significant groin, flank, abdominal, back pain or haemodynamic instability following an interventional procedure. Spontaneous haemorrhage usually occurs in patients who are anticoagulated. Multi-slice CT and arteriography are important for diagnosis. Most haemodynamically stable patients can be managed with fluid resuscitation, correction of coagulopathy and blood transfusion. Endovascular treatment involving selective intra-arterial embolisation or the deployment of stent-grafts over the punctured vessel is attaining an increasingly important role. Open repair of retroperitoneal bleeding vessels should be reserved for cases when there is failure of conservative or endovascular measures to control the bleeding. Open repair is also required if endovascular facilities or expertise is unavailable and in cases where the patient is unstable. If treated inappropriately, the mortality of patients with retroperitoneal haematoma remains high.

CONCLUSION

There is a lack of level I evidence for the best management plans for retroperitoneal haematoma, and evidence is based on small cohort series or isolated case reports. Conservative management should only be reserved for patients who are stable. Interventional radiology with intra-arterial embolisation or stent-grafting is the treatment of choice. Open surgery is now rarely required.

Cardiovascular risk factors for physician-diagnosed lumbar disc herniation

BACKGROUND CONTEXT

Despite the high prevalence of lumbar disc disease among the general population, the determinants of this condition remain poorly understood. A recent hypothesis suggests that atherosclerotic vascular disease may play an important role in the etiology of this disorder.

PURPOSE

To explore the relationship between cardiovascular risk factors and the incidence of lumbar disc herniation.

STUDY DESIGN/SETTING

We prospectively examined the association between smoking, high cholesterol, high blood pressure, obesity, and diabetes and self-reported lumbar disc herniation. The study was conducted among 98,407 female nurses who in 1976 were ages 30-55 years, free of cancer (except non-melanoma skin cancer), lumbar disc disease, and who responded to the 1992 questionnaire regarding whether or not a physician diagnosis of lumbar disc herniation had been made.

RESULTS

During 16 years of follow-up (438,662 person-years), 2,727 nurses who were free of cancer reported a physician-diagnosed lumbar disc herniation that was confirmed either by computed tomography or magnetic resonance imaging. After adjusting for age, body mass index, smoking, vigorous or moderate exercise, employment status, having seen a physician in the last year, and each of the following other factors, the multivariate relative risk for diabetes was 1.52 (95% confidence interval [95% CI], 1.17 to 1.98); for hypertension it was 1.25 (95% CI, 1.11 to 1.41); for high cholesterol it was 1.26 (95% CI, 1.10 to 1.44), and for having a parent who had suffered a myocardial infarction before age 60 it was 1.13 (95% CI, 1.02 to 1.26). In these models, compared with never smokers, the relative risk for past smokers was 1.10 (95% CI, 1.00 to 1.20), for current smokers the risk increased with the number of cigarettes smoked per day. A decrease in risk occurred after cessation. Also in these models, we noted a significant trend of increasing risk with higher body mass index (p=.01).

CONCLUSIONS

Cardiovascular risk factors are significantly and independently associated with symptomatic lumbar disc herniation. These findings provide further confirmation that atherosclerosis may be involved in spinal disc degeneration. Modification of risk factors, particularly smoking, may also prove to be beneficial.

MR aortography and serum cholesterol levels in patients with long-term nonspecific lower back pain

STUDY DESIGN

A cross-sectional analysis of the feeding arteries of the lumbar spine and cholesterol levels on patients with long-term nonspecific lower back pain.

OBJECTIVES

To evaluate whether occlusion of lumbar and middle sacral arteries or serum cholesterol levels are associated with lower back pain and/or with disc degeneration.

SUMMARY OF BACKGROUND DATA

Atherosclerosis in the wall of the abdominal aorta usually develops at the ostia of branching arteries and the bifurcation, and may obliterate orifices of lumbar and middle sacral arteries. Obstruction of these arteries causes ischemia in the lumbar spine and may result in back symptoms and disc degeneration.

METHODS

MR aortography and cholesterol blood tests were performed on 51 patients with long-term lower back pain without specific findings (i.e., spinal or nerve root compression) in regular lumbar MR images. The patients ranged from 35 to 70 years of age (mean age, 56 years). Serum cholesterol and low-density lipoprotein (LDL) cholesterol levels were measured. To assess symptoms and disability NASS low back Outcome Instrument was used.

RESULTS

Twenty-nine (78%) of 37 men and 11 (77%) of 14 women showed occluded lumbar and/or middle sacral arteries. The prevalence of occluded arteries was 2.5 times more than in subjects of corresponding age group in a Finnish necropsy material. Twenty-three (62%) men and seven (50%) women had significant disc degeneration. Disc degeneration was associated with occluded lumbar/middle sacral arteries (P = 0.035). Patients with occluded arteries or significant disc degeneration did not complain more severe symptoms than those without, whereas patients with above normal serum LDL cholesterol scored higher in neurogenic symptoms (P = 0.031) and complained more often severe pain (P = 0.049) than those with normal LDL cholesterol.

CONCLUSIONS

The study indicates that lumbar and middle sacral arteries are often occluded in patients with nonspecific long-term lower back pain. Occlusion of these arteries may also be associated with disc degeneration.

Endovascular Embolization of Spontaneous Retroperitoneal Hemorrhage Secondary to Anticoagulant Treatment

The purpose of this study was to report a single hospital's experience of endovascular treatment of patients with retroperitoneal hemorrhage (RPH) secondary to anticoagulant treatment. Ten consecutive patients treated in an intensive care unit and needing blood transfusions due to RPH secondary to anticoagulation were referred for digital subtraction angiography (DSA) to detect the bleeding site(s) and to evaluate the possibilities of treating them by transcatheter embolization. DSA revealed bleeding site(s) in all 10 patients: 1 lumbar artery in 4 patients, 1 branch of internal iliac artery in 3 patients and multiple bleeding sites in 3 patients. Embolization could be performed in 9 of them. Coils, gelatin and/or polyvinyl alcohol were used as embolic agents. Bleeding stopped or markedly decreased after embolization in 8 of the 9 (89%) patients. Four patients were operated on prior to embolization, but surgery failed to control the bleeding in any of these cases. Abdominal compartment syndrome requiring surgical or radiological intervention after embolization developed in 5 patients. One patient died, and 2 had sequelae due to RPH. All 7 patients whose bleeding stopped after embolization had a good clinical outcome. Embolization seems to be an effective and safe method to control the bleeding in patients with RPH secondary to anticoagulant treatment when conservative treatment is insufficient.

Chronic Chlamydia pneumoniae infection increases the risk of occlusion of lumbar segmental arteries of patients with sciatica: a 3-year follow-up study

STUDY DESIGN

A magnetic resonance imaging follow-up study of lumbar arteries among patients with sciatica with chronic Chlamydia pneumoniae infection.

OBJECTIVE

To determine whether chronic infection causes occlusion of lumbar arteries.

SUMMARY OF BACKGROUND DATA

C. pneumoniae infection is associated with coronary heart disease, and the infectious pathogen has also been detected in abdominal aortic aneurysms and in atherosclerotic plaques. No studies are available on the effect of this infectious agent on lumbar arteries.

METHODS

Chronic infection was defined as persistent high positive immunoglobulin G and/or immunoglobulin A antibodies and/or the presence of immune complexes. The lumbar arteries, evaluated with two-dimensional time-of-flight magnetic resonance angiography, were scored as normal, narrowed, or occluded. The differences in the segmental and whole lumbar spine (segments L1-L4) sum of arterial occlusion at baseline and at 3 years, and the incidence of new arterial stenosis were compared in patients with and without chronic infection using the Kolmogorov-Smirnov test.

RESULTS

Patients with chronic infection were more likely to be persistent smokers (P = 0.006), male (P = 0.04), and more obese (P = 0.02) compared to patients with normal antibody levels. They had significantly higher degree of arterial stenosis at L4 segment at baseline and at 3 years (P = 0.001 and 0.002, respectively), in the whole lumbar spine at baseline and at 3 years (P < 0.001 for both), and at L1 and L3 segments at 3 years (P = 0.013 for both). The incidence of new arterial stenosis was similar in both patient groups. Patients with chronic infection also had significantly higher grade of endplate degeneration at L4-L5 (P = 0.008).

CONCLUSIONS

The results of this study suggest that chronic C. pneumoniae infection may induce stenosis of lumbar arteries.

Delayed diagnosis of a false aneurysm after lumbar arterial injury: treatment with endovascular embolization: a case report

STUDY DESIGN

A case report is presented.

OBJECTIVES

To report a case of lumbar artery pseudoaneurysm that was primarily missed, and to discuss therapeutic options.

SUMMARY OF BACKGROUND DATA

In the literature, only a few cases of lumbar artery pseudoaneurysms have been reported. The diagnosis is difficult and often delayed, with a sometimes fatal outcome. The treatment is either surgery or endovascular embolization.

METHODS

In a patient who survived after a fall from 20 feet (6 m) height, a relatively small retroperitoneal hematoma detected during urgent splenectomy was underestimated. Two weeks later, the underlying laceration of the lumbar artery led to the formation of a pseudoaneurysm, which then ruptured causing a large retroperitoneal hematoma and gradual complete femoral nerve palsy.

RESULTS

Complete occlusion of the pseudoaneurysm and progressive regression of the retroperitoneal hematoma were achieved by two stages of endovascular embolization. The size of the hematoma was diminished gradually during a period of 12 months, whereas the femoral nerve has completely recovered.

CONCLUSIONS

Traumatic rupture of a lumbar artery is a rare complication of a blunt abdominal trauma. This condition leads to a potentially massive retroperitoneal hemorrhage and shock, or to subsequent pseudoaneurysm formation and delayed retroperitoneal hematoma. This condition can be managed with either surgical or preferably endovascular intervention provided the patient is hemodynamically stable.

Disc degeneration/back pain and calcification of the abdominal aorta. A 25-year follow-up study in Framingham

STUDY DESIGN

A 25-year follow-up study of 606 members of the population-based Framingham cohort, who had received lateral lumbar radiographs in 1967-1968 and 1992-1993, and completed an interview on back symptoms at the second examination.

OBJECTIVES

To evaluate whether calcific lesions in the posterior wall of the abdominal aorta, the source of the feeding arteries of the lumbar spine, are associated with disc degeneration or back pain, which would suggest that ischemia of the lumbar spine leads to disc degeneration.

METHODS

The presence of radiographic aortic calcification was ascertained in front of each lumbar segment from L1 through L4, and disc degeneration at intervertebral spaces from L1-L2 through L4-L5. The associations between aortic calcification, disc degeneration, and back pain were tested using logistic regression with adjustment for age and sex.

RESULTS

At the baseline examination, aortic calcification was significantly associated with general disc degeneration, that is, disc space narrowing or endplate sclerosis at any lumbar level (odds ratio 1.6; 95% confidence interval 1.0-2.5; P = 0.034). In longitudinal, level-specific analyses, comparing local aortic calcifications with disc degeneration at the matching level, aortic calcifications predicted disc deterioration, that is, a decrease in disc space or appearance of endplate sclerosis, between the examinations (odds ratio 1.5; 95% confidence interval 1.3-1.8; P < 0.001). Furthermore, subjects in whom aortic calcifications developed between the examinations had disc deterioration twice as frequently as those in whom aortic calcifications did not develop (odds ratio 2.0; 96% confidence interval 1.2-3.5; P = 0.013). Also, individuals with severe (Grade 3) posterior aortic calcification in front of any lumbar segment were more likely than others to report back pain during adult life (odds ratio 1.6; 95% confidence interval 1.1-2.2; P = 0.014).

CONCLUSIONS

Advanced aortic atherosclerosis, presenting as calcific deposits in the posterior wall of the aorta, increases a person's risk for development of disc degeneration and is associated with the occurrence of back pain.