Is cauda equina syndrome linked with obesity?

Association between chiropractic spinal manipulation and cauda equina syndrome in adults with low back pain: Retrospective cohort study of US academic health centers

BACKGROUND

Cauda equina syndrome (CES) is a lumbosacral surgical emergency that has been associated with chiropractic spinal manipulation (CSM) in case reports. However, identifying if there is a potential causal effect is complicated by the heightened incidence of CES among those with low back pain (LBP). The study hypothesis was that there would be no increase in the risk of CES in adults with LBP following CSM compared to a propensity-matched cohort following physical therapy (PT) evaluation without spinal manipulation over a three-month follow-up period.

METHODS

A query of a United States network (TriNetX, Inc.) was conducted, searching health records of more than 107 million patients attending academic health centers, yielding data ranging from 20 years prior to the search date (July 30, 2023). Patients aged 18 or older with LBP were included, excluding those with pre-existing CES, incontinence, or serious pathology that may cause CES. Patients were divided into two cohorts: (1) LBP patients receiving CSM or (2) LBP patients receiving PT evaluation without spinal manipulation. Propensity score matching controlled for confounding variables associated with CES.

RESULTS

67,220 patients per cohort (mean age 51 years) remained after propensity matching. CES incidence was 0.07% (95% confidence intervals [CI]: 0.05-0.09%) in the CSM cohort compared to 0.11% (95% CI: 0.09-0.14%) in the PT evaluation cohort, yielding a risk ratio and 95% CI of 0.60 (0.42-0.86; p = .0052). Both cohorts showed a higher rate of CES during the first two weeks of follow-up.

CONCLUSIONS

These findings suggest that CSM is not a risk factor for CES. Considering prior epidemiologic evidence, patients with LBP may have an elevated risk of CES independent of treatment. These findings warrant further corroboration. In the meantime, clinicians should be vigilant to identify LBP patients with CES and promptly refer them for surgical evaluation.

Obesity increases the odds of intervertebral disc herniation and spinal stenosis; an MRI study of 1634 low back pain patients

PURPOSE

The objective of this study was to examine the relationships between BMI and intervertebral disc degeneration (DD), disc herniation (DH) and spinal stenosis (SS) using a large, prospectively recruited and heterogeneous patient population.

METHODS

Patients were recruited through the European Genodisc Study. An experienced radiologist scored MRI images for DD, DH and SS. Multivariate linear and logistic regression analyses were used to model the relationship between these variables and BMI with adjustment for patient and MRI confounders.

RESULTS

We analysed 1684 patients with a mean age of 51 years and BMI of 27.2 kg/m2.
The mean DD score was 2.6 (out of 5) with greater DD severity with increasing age (R2 = 0.44). In the fully adjusted model, a 10-year increase in age and a 5 kg/m2 increase in BMI were associated, respectively, with a 0.31-unit [95% CI 0.29,0.34] and 0.04-unit [CI 0.01,0.07] increase in degeneration. Age (OR 1.23 [CI 1.06,1.43]) and BMI (OR 2.60 [CI 2.28,2.96]) were positively associated with SS. For DH, age was a negative predictor (OR 0.70 [CI 0.64,0.76]) but for BMI (OR 1.19 [CI 1.07,1.33]), the association was positive. BMI was the strongest predictor of all three features in the upper lumbar spine.

CONCLUSIONS

While an increase in BMI was associated with only a slight increase in DD, it was a stronger predictor for DH and SS, particularly in the upper lumbar discs, suggesting weight loss could be a useful strategy for helping prevent disorders associated with these pathologies.

EVALUATION OF SYMPTOMATIC DEGENERATIVE LUMBAR STENOSIS WITH PROBABLE DETERMINING FACTORS

ABSTRACT Objective: To evaluate degenerative lumbar stenosis in symptomatic patients submitted to surgeryand the correlation between probable determining factors. Methods: A retrospective descriptive study in which themagnetic resonance images of 73 patients with degenerative stenosis,who underwent surgeries involving 141 levels performed by a single surgeon at the Hospital Ortopédico de Passo Fundo from 2015 to 2018, were evaluated. The patients were stratified by the degree of facet tropism, facet arthrosis, disc degeneration, and operated side, as well as by epidemiological data such as age, sex, etc. Tropism was measured using the Karacan method and evaluated numerically and categorically. Disc degeneration was classified by Pfirrmann and facet arthrosis by Weishaupt. To analyze and obtain the results, the Chi-square test and ANOVA were used with the SPSS statistical program, version 18.0. Results: Statistical significance was found in the relationship between facet tropism and disc degeneration (p=0.026) at the L4-L5 level. No correlation was found between tropism and facet arthrosis (p=0.161) or tropism and the operated side (p=0.573). Conclusion: The degree of tropism directly influences disc degeneration and greater asymmetries are related to more severe degenerations. Although tropism has not shown a statistically significant correlation with the operated side (p=0.573), it is believed that further studies should be carried out on this correlation. Level of evidence II; Retrospective study.

Body mass index has an impact on preoperative symptoms but not clinical outcome in acute cauda equina syndrome

Cauda equina syndrome (CES) presents a surgical emergency with treatment required within 48 h. Symptoms include reduced saddle sensation, micturition difficulties, and/or anal sphincter impairment. Controversy exists regarding the effect on and coincidence of overweight with CES. We performed a retrospective case-control study of all patients treated surgically for acute complete and incomplete CES in our neurosurgical department from 2009 to 2020, focusing on the preoperative BMI and postoperative neurological outcome. In addition, we performed a comprehensive literature review. Fifty patients with CES were included, of whom 96% suffered from a decompensated lumbar spinal stenosis or disc prolapse between the L4/5 and L5/S1 levels. Our cohort population was overweight but not obese: mean BMI was 27.5 kg/m², compared with 27.6 kg/m² in patients with degenerative spine surgery. BMI did not significantly influence the postoperative outcome, but it did affect preoperative symptoms and surgery duration. Symptom duration significantly differed depending on the underlying cause for CES. The literature review revealed sparse evidence, with only four clinical case series presenting contradictory results. We provide a comprehensive literature review on the current evidence regarding CES and obesity and conclude that we did not observe an association between obesity and CES occurrence. Patients with CES and other degenerative spinal pathologies belong to an overweight but not obese population. Body Mass Index has an impact on preoperative symptoms but not clinical outcome in acute CES.

Are There Any Risk Factors Associated with the Presence of Cauda Equina Syndrome in Symptomatic Lumbar Disk Herniation?

OBJECTIVE

Risk factors for developing cauda equina syndrome (CES) caused by lumbar disk herniation (LDH) remain controversial and have not been established yet. The aim of the study was to investigate whether there is a relationship among age, sex, body mass index (BMI), or the degree of spinal canal compromise and the presence of CES in patients undergoing lumbar microdiskectomy.

METHODS

Between 2015 and 2019, 506 patients who had an operation for LDH compressing the dural sac were prospectively identified. The "prolapse-to-canal ratio" (PCR) was calculated as a proportion of the cross-sectional area of the disk prolapse compared with the total cross-sectional area of the spinal canal.

RESULTS

In total, 35 CES (6.9%) patients were identified. Multivariate logistic regression, adjusted for age, gender, BMI, and PCR, shows that only PCR was associated with the presence of CES (P < 0.001, area under the curve 0.7431). BMI was not associated with an increased risk of CES.

CONCLUSIONS

This study demonstrates a significant correlation between the size of LDH relative to size of the spinal canal and the presence of CES. A finding of LDH causing >60% obstruction of the spinal canal should be considered a red flag, and such patients need to be watched more closely.

Surgical Intervention for Cauda Equina Syndrome in the Second and Third Trimesters of Pregnancy: A Report of Three Cases

CASE

Low back pain affects >50% of pregnant women. However, cauda equina syndrome (CES) during pregnancy is rare. Because a delay in treatment increases the risk of irreversible neurologic damage, acute onset is regarded as a surgical emergency. We describe 3 cases of CES in pregnant women at 24, 27, and 30 weeks' gestation, respectively.

CONCLUSION

All 3 of the patients underwent surgical decompression in the prone position under general anesthesia with continuous external monitoring of the fetal heart rate. Intraoperative findings were noteworthy for epidural venous plexus engorgement in 2 of the patients. There were no complications for the patients or the fetuses, and all 3 of the patients had postoperative resolution of the neurologic symptoms.

Evaluation and management of cauda equina syndrome in the emergency department

BACKGROUND

Cauda equina syndrome (CES) may be a devastating disease with the potential for significant patient morbidity. It is essential for emergency clinicians to be aware of how to effectively diagnose and manage this condition.

OBJECTIVE

This article provides a narrative review of the diagnosis and management of CES for the emergency clinician.

DISCUSSION

Cauda equina syndrome is a rare but emergent condition associated with back pain. It can result in severe morbidity and can be due to a variety of causes, most commonly vertebral disc protrusion. Diagnosis is often delayed, which may result in a poor prognosis. Red flags and findings consistent with CES include bilateral neurogenic sciatica, reduced perineal sensation, altered bladder function leading to painless urinary retention, loss of anal tone, and loss of sexual function. In isolation, history and examination findings demonstrate poor sensitivity. Symptoms may occur either suddenly or gradually, and most patients do not present with all of these symptoms. Postvoid bladder volume assessments can assist in the evaluation, but the diagnosis typically involves magnetic resonance imaging (MRI) or computed tomography myelography if MRI is not available. Treatment relies upon surgical consultation and operative intervention for decompression.

CONCLUSION

Cauda equina syndrome can be a difficult diagnosis. However, knowledge of the history and examination findings, imaging, and treatment can assist the emergency clinician in optimizing management of this condition.

Obesity and spinal epidural lipomatosis in cauda equina syndrome

BACKGROUND CONTEXT

Although lumbar disc herniations are common, only a small portion of these herniations lead to cauda equina syndrome (CES), which is an uncommon but debilitating disorder. Why some patients with herniation develop CES, when most do not, remains unknown. Preexisting subclinical epidural lipomatosis may limit canal space such that an otherwise benign herniation causes CES.

PURPOSE

This study determines whether patients with an acute disc herniation and CES have a greater body mass index (BMI) and greater quantity of epidural fat compared with control subjects with non-CES symptomatic lumbar herniated discs.

STUDY DESIGN/SETTING

A retrospective case-control series at a university-based level-1 trauma center was carried out.

PATIENT SAMPLE

There were 33 CES and 66 control subjects identified from a prospectively maintained database of patients who underwent surgical management for a lumbar disc herniation between 2007 and 2012. Each CES case had two non-CES control patients matched by gender and age within 5 years except 5 CES cases that matched only one non-CES control.

OUTCOME MEASURES

The outcome measures included weight, height, age, gender, and BMI. Radiographic outcome measures included the proportion of lumbar spinal canal occupied by fat and herniated disc on preoperative magnetic resonance imaging.

METHODS

Patient charts and preoperative radiographs were retrospectively reviewed. For each patient, a blinded reviewer determined the proportion of lumbar spinal canal occupied by fat, and the maximal proportion of the canal occupied by herniated material at the involved level. Patient demographics and radiographic measures were compared between CES and control groups using chi-square or Student t tests. A second blinded reviewer re-assessed a series of radiographs, and the intraobserver variability was determined by Spearman correlation. Logistic regression was used to model the preoperative factors associated with having an acute disc herniation and CES.

RESULTS

The CES cases had higher BMI (31.8 kg/m², 95% confidence interval [CI] 29.5-34.0 vs. 28.1 kg/m², 95% CI 26.7-29.5 in controls; p=.007), focally narrower canals (14.6 mm, 95% CI 13.8-15.3 mm vs. 16.4 mm, 95% CI 15.4-17.3 mm in controls; p=.003), and a greater percentage of spinal canal occupied by epidural fat (31.3%, 95% CI 26.1%-36.6% vs. 21.9%, 95% CI 18.7%-25.1% in controls; p=.003) and herniated disc material (54.5%, 95% CI 46.9%-62.0% vs. 34.4%, 95% CI 30.3%-38.5% in controls; p<.0001). Logistic regression confirmed canal width at the involved level, BMI, amount of canal occupied disc, and proportion of canal occupied by fat as independent predictors of having an acute disc herniation and CES.

CONCLUSIONS

Obesity is a risk factor for CES from disc herniation. The CES cases also had a greater amount of herniated material, focally narrower canal, and larger epidural fat deposits. The latter may be the mechanism linking obesity with CES.

Prevalence of lumbar spinal stenosis, using the diagnostic support tool, and correlated factors in Japan: a population-based study

BACKGROUND

Few studies have examined the prevalence of lumbar spinal stenosis (LSS) in the general population. The purposes of this study were to estimate the prevalence of LSS and to investigate correlated factors for LSS in Japan.

METHODS

A questionnaire survey was performed on 4,400 subjects selected from residents aged 40-79 years in Japan by stratified two-stage random sampling in 2010. The question items consisted of lower-limb symptoms suggestive of LSS, the diagnostic support tool for LSS (LSS-DST), demographic and lifestyle characteristics, comorbidities, the Japanese Perceived Stress Scale (JPSS), and the Mental Health Index 5 (MHI-5). Using the LSS-DST, the presence of LSS was predicted to estimate the prevalence of LSS. Logistic regression analysis was performed to examine the relationship between LSS and correlated factors.

RESULTS

Questionnaires were obtained from 2,666 subjects (60.6 %), consisting of 1,264 males (47.4 %). The mean (standard deviation) age was 60.0 (10.9) years. According to the LSS-DST, 153 subjects were regarded as having LSS. The prevalence was estimated to be 5.7 %. When standardizing this value with the age distribution of the Japanese population, it was estimated that 3,650,000 Japanese subjects aged 40-79 years might have LSS using the LSS-DST. Prevalence increased with age and was particularly high in subjects aged 70-79 years, irrespective of gender. As correlated factors, an advanced age (60 years or older), diabetes mellitus, urological disorders, and osteoarthritis/fracture as comorbidities, and depressive symptoms, were associated with LSS.

CONCLUSIONS

This study elucidated the prevalence of LSS and factors associated with LSS in Japan. This is the first report describing the estimated prevalence of LSS and associated factors using a strictly sampled representative population.