Diabetes Mellitus, a New Risk Factor for Lumbar Spinal Stenosis: A Case-Control Study

Diabetes Mellitus and Poor Glycemic Control Are Associated With a Higher Risk of Lumbar Spinal Stenosis: An Analysis of a Large Nationwide Database

STUDY DESIGN

A large-scale retrospective case-control study.

OBJECTIVE

Examine diabetes as a risk factor for lumbar spinal stenosis (LSS) development and evaluate the impact of diabetes duration, glycemic control, and associated complications on this risk.

SUMMARY OF BACKGROUND DATA

Diabetes mellitus, a multiorgan disorder impacting various connective tissues, induces histological changes in spinal structures, particularly the ligamentum flavum. While clinical studies suggest a higher incidence of LSS in diabetic patients, substantial epidemiological research on the likelihood of LSS diagnosis in individuals with diabetes is scarce.

MATERIALS AND METHODS

Using nationwide data, a total of 49,576 patients diagnosed with LSS based on International Classification of Diseases-10 codes were matched with controls of the same number based on age and sex. Employing a multivariable logistic regression model, the study assessed for the association between spinal stenosis and diabetes, while adjusting for confounders.

RESULTS

We found a higher likelihood of LSS diagnosis in diabetic patients [odds ratio (OR) 1.39, 95% CI: 1.36 - 1.43, P <0.001]. Those with hemoglobin A1c ≥7% and ≥1 diabetes-related complication also had an elevated likelihood (OR: 1.19, 95% CI: 1.08-1.31, P =0.001). Prolonged diabetes exposure increased the risk. Diabetes diagnosis reduced median survival by around 4.5 years for both stenosis and nonstenosis patients; spinal stenosis diagnosis alone minimally impacted survival. Relative to individuals diagnosed with diabetes mellitus at the age of 65 or older, the OR for developing LSS were 1.22 (95% CI: 1.18-1.27, P <0.001) when DM was diagnosed at 50 to 65 years old and 1.67 (95% CI: 1.56-1.79, P <0.001) for those under 50 years old. Multivariate analysis revealed a significantly increased risk of all-cause mortality in patients with DM and spinal stenosis (hazard ratio: 1.36, 95% CI: 1.29-1.44, P <0.001) and those with DM without stenosis (hazard ratio: 1.49, 95% CI: 1.41-1.57, P <0.001) compared with controls.

CONCLUSIONS

Diabetic patients with prolonged disease, poor glycemic control, and diabetes-related complications face an elevated risk of developing LSS. Recognizing the reciprocal adverse relationship between these conditions is crucial in clinical practice and designing public health measures for managing both conditions.

LEVEL OF EVIDENCE

4.

Development of multidisciplinary, evidenced-based protocol recommendations and implementation strategies for anterior lumbar interbody fusion surgery following a literature review

The anterior lumbar interbody fusion (ALIF) procedure involves several surgical specialties, including general, vascular, and spinal surgery due to its unique approach and anatomy involved. It also carries its own set of complications that differentiate it from posterior lumbar fusion surgeries. The demonstrated benefits of treatment guidelines, such as Enhanced Recovery after Surgery in other surgical procedures, and the lack of current recommendations regarding the anterior approach, underscores the need to develop protocols that specifically address the complexities of ALIF. We aimed to create an evidence-based protocol for pre-, intra-, and postoperative care of ALIF patients and implementation strategies for our health system. A 12-member multidisciplinary workgroup convened to develop an evidence-based treatment protocol for ALIF using a Delphi consensus methodology and the Grading of Recommendations, Assessment, Development, and Evaluation (GRADE) system for rating the quality of evidence and strength of protocol recommendations. The quality of evidence, strength of the recommendation and specific implementation strategies for Methodist Health System for each recommendation were described. The literature search resulted in 295 articles that were included in the development of protocol recommendations. No disagreements remained once the authors reviewed the final GRADE assessment of the quality of evidence and strength of the recommendations. Ultimately, there were 39 protocol recommendations, with 16 appropriate preoperative protocol recommendations (out of 17 proposed), 9 appropriate intraoperative recommendations, and 14 appropriate postoperative recommendations. This novel set of evidence-based recommendations is designed to optimize the patient's ALIF experience from the preoperative to the postoperative period.

High prevalence of lumbar spinal stenosis in cases of idiopathic normal-pressure hydrocephalus affects improvements in gait disturbance after shunt operation

Objective

Idiopathic normal-pressure hydrocephalus (iNPH) is characterized by symptoms of dementia, urinary incontinence, and gait disturbance; however, gait disturbance tends to persist after shunt surgery. Gait disturbance and urinary dysfunction are also major symptoms of lumbar spinal stenosis (LSS). Currently, the epidemiology of the complications of LSS in iNPH is unclear. Here, we evaluated the coexistence rate of LSS in iNPH cases.

Methods

This was a retrospective case-control study. Between 2011 and 2017, 224 patients with a median age of 78 years, including 119 males, were diagnosed with iNPH and underwent lumboperitoneal shunts or ventriculoperitoneal shunts. LSS was diagnosed with magnetic resonance imaging by two spine surgeons. Age, sex, body mass index (BMI), Timed Up and Go (TUG) test, Mini Mental State Examination (MMSE) score, and urinary dysfunction were examined. We compared the changes in these variables in the group of patients with iNPH without LSS versus those with both iNPH and LSS.

Results

Seventy-three iNPH patients (32.6%) with LSS had significantly higher age and BMI. The existence of LSS did not alter the postoperative improvement rates of MMSE and urinary dysfunction; however, TUG improvement was significantly impaired in the LSS-positive group.

Conclusions

LSS affects improvements in gait disturbance of iNPH patients after shunt operation. Because our results revealed that one-third of iNPH patients were associated with LSS, gait disturbance observed in iNPH patients should be considered a potential complication of LSS.

Minimally Invasive vs. Open Surgery for Lumbar Spinal Stenosis in Patients with Diabetes - A Canadian Spine Outcomes and Research Network Study

STUDY DESIGN

Retrospective cohort.

OBJECTIVES

To compare outcomes of minimally invasive surgery (MIS) vs open surgery (OPEN) for lumbar spinal stenosis (LSS) in patients with diabetes.

METHODS

Patients with diabetes who underwent spinal decompression alone or with fusion for LSS within the Canadian Spine Outcomes and Research Network (CSORN) database were included. MIS vs OPEN outcomes were compared for 2 cohorts: (1) patients with diabetes who underwent decompression alone (N = 116; MIS n = 58 and OPEN n = 58), (2) patients with diabetes who underwent decompression with fusion (N = 108; MIS n = 54 and OPEN n = 54). Modified Oswestry Disability Index (mODI) and back and leg pain were compared at baseline, 6-18 weeks, and 1-year post-operation. The number of patients meeting minimum clinically important difference (MCID) or minimum pain/disability at 1-year was compared.

RESULTS

MIS approaches had less blood loss (decompression alone difference 100 mL, P = .002; with fusion difference 244 mL, P < .001) and shorter length of stay (LOS) (decompression alone difference 1.2 days, P = .008; with fusion difference 1.2 days, P = .026). MIS compared to OPEN decompression with fusion had less patients experiencing adverse events (AEs) (difference 13 patients, P = .007). The MIS decompression with fusion group had lower 1-year mODI (difference 14.5, 95% CI [7.5, 21.0], P < .001) and back pain (difference 1.6, 95% CI [.6, 2.7], P = .002) compared to OPEN. More patients in the MIS decompression with fusion group exceeded MCID at 1-year for mODI (MIS 75.9% vs OPEN 53.7%, P = .028) and back pain (MIS 85.2% vs OPEN 70.4%, P = .017).

CONCLUSIONS

MIS approaches were associated with more favorable outcomes for patients with diabetes undergoing decompression with fusion for LSS.

Modulation of the biological network of lumbar spinal stenosis by Tongdu Huoxue Decoction based on clinical metabolomics

Objective: To explore the clinical efficacy and metabolic mechanism of Tongdu Huoxue Decoction (THD) in treating lumbar spinal stenosis (LSS). Methods: A total of 40 LSS patients and 20 healthy participants were recruited from January 2022 to June 2022. The patients' pre- and post-treatment visual analogue scale (VAS) and Japanese Orthopaedic Association (JOA) scores were recorded. ELISA kits were used to assess pre- and post-treatment levels of serum Interleukin-1beta (IL-1β), Alpha tumour necrosis factor (TNF-α) and prostaglandin E2 (PGE2). Finally, the patients' pre- and post-treatment and healthy human sera were subjected to extensively targeted metabolomics using Ultra Performance Liquid Chromatography (UPLC) to identify potential differential metabolites and metabolic pathways using multivariate statistical analysis. Results: Compared to the pre-treatment (group A), the patients' VAS scores decreased significantly (p < 0.05), while JOA scores increased significantly (p < 0.05) post-treatment (group B), indicating that THD could effectively improve the pain and lumbar spine function of LSS patients. Moreover, THD could effectively inhibit the expression of IL-1β, TNF-α and PGE2-associated inflammatory factors in serum. Regarding metabolomics, the levels of 41 differential metabolites were significantly different in the normal group (group NC) compared to group A, and those were significantly restored after treatment with THD, including chenodeoxycholic acid 3-sulfate, taurohyodeoxycholic acid, 3,5-Dihydroxy-4-methoxybenzoic acid, pinocembrin. These biomarkers are mainly involved in purine metabolism, steroid hormone biosynthesis and amino acid metabolism. Conclusion: This clinical trial demonstrated that THD is effective in improving pain, lumbar spine function and serum levels of inflammation in patients with LSS. Moreover, its mechanism of action is related to the regulation of purine metabolism, steroid hormone biosynthesis and the expression of key biomarkers in the metabolic pathway of amino acid metabolism.

Ligament Alteration in Diabetes Mellitus

Connective tissue ageing is accelerated by the progressive accumulation of advanced glycation end products (AGEs). The formation of AGEs is characteristic for diabetes mellitus (DM) progression and affects only specific proteins with relatively long half-lives. This is the case of fibrillar collagens that are highly susceptible to glycation. While collagen provides a framework for plenty of organs, the local homeostasis of specific tissues is indirectly affected by glycation. Among the many age- and diabetes-related morphological changes affecting human connective tissues, there is concurrently reduced healing capacity, flexibility, and quality among ligaments, tendons, bones, and skin. Although DM provokes a wide range of known clinical disorders, the exact mechanisms of connective tissue alteration are still being investigated. Most of them rely on animal models in order to conclude the patterns of damage. Further research and more well-designed large-cohort studies need to be conducted in order to answer the issue concerning the involvement of ligaments in diabetes-related complications. In the following manuscript, we present the results from experiments discovering specific molecules that are engaged in the degenerative process of connective tissue alteration. This review is intended to provide the report and sum up the investigations described in the literature concerning the topic of ligament alteration in DM, which, even though significantly decreasing the quality of life, do not play a major role in research.

Impact of lumbar spinal stenosis on metabolic syndrome incidence in community-dwelling adults in Aizu cohort study (LOHAS)

Metabolic syndrome and lumbar spinal stenosis (LSS) are common age-related diseases. However, the causal relationship between them remains unclear. This study aimed to identify the effects of LSS on metabolic syndrome incidence in community-dwelling adults. This prospective cohort study included participants of the Aizu cohort study (LOHAS) aged < 75 years as of 2008. Participants with metabolic syndrome at baseline were excluded. The primary outcome measure was metabolic syndrome incidence, and the main explanatory variable was the presence of LSS, as assessed by a self-reported questionnaire. A multivariate Cox proportional hazard regression model was used to estimate hazard ratios (HRs) for metabolic syndrome incidence during the 6-year follow-up period. Complete-case analyses were compared with the multiple imputation results. Among 1599 participants, 1390 complete cases were analyzed (mean [SD] age 62.3 [9.0] years; females, 734 [52.8%]). Among those participants, 525 (37.8%) developed metabolic syndrome during the follow-up of 3.89 [1.96] years. The presence of LSS was associated with developing metabolic syndrome (HR, 1.41; 95% confidence interval [CI] 1.02–1.95). Multiple imputation results showed similar trends of those having complete-case data (HR, 1.47; 95% CI 1.08–2.00). This finding suggests the importance of prevention and management of LSS in community settings.

Diabetes Mellitus-A Risk Factor for the Development of Lumbar Disc Degeneration: A Retrospective Study of an Indian Population

STUDY DESIGN

A retrospective study.

OBJECTIVES

To determine the association between type-2 diabetes mellitus (T2DM) and the severity of lumbar disc degeneration disease (LDDD).

METHODS

We included 199 patients with low back pain (LBP) who visited our hospital from 2016 to 2018. All patients were divided into 3 groups as per inclusion criteria. Group A, patients without DM (n = 75); group B, patients with controlled DM (n = 72); and group C, patients with uncontrolled DM (n = 52). The patients were further subdivided into group B1, DM duration ≤10 years (n = 38); group B2, DM duration >10 years (n = 34); group C1 DM duration ≤10 years (n = 28); and group C2, DM duration >10 years (n = 24). Sex, age, body mass index, occupation, smoking history, alcohol use, and duration of T2DM were recorded. The severity of LDDD was evaluated using the 5-level Pfirrmann grading system. Operated patients' disc materials were sent for histological examination.

RESULTS

Demographic data showed no difference among groups (P > 0.5), except age. Patients with DM showed more severe disc degeneration compared with patients without DM. The average Pfirrmann scores between groups A and B1 had no difference; groups B2, C1, and C2 showed higher average Pfirrmann scores than group A (P < 0.05). Groups B2 and C2 showed higher average Pfirrmann scores than groups B1 and C1 (P < 0.05). Groups C1 and C2 showed higher average Pfirrmann scores than groups B1 and B2 (P < 0.05). The severity of LDDD was significantly related to DM duration in both groups B and C (P < 0.05). DM groups showed increased disc apoptosis and matrix aggrecan fragmentation, disc glycosaminoglycan content and histological analysis were significantly different; the results are similar to Pfirrmann score results.

CONCLUSIONS

DM duration >10 years and uncontrolled DM were risk factors for LDDD.

Dietary factors and the risk of lumbar spinal stenosis: A case-control analysis from the PREFACE study

BACKGROUND AND AIMS

There is a lack of knowledge on the association of dietary factors and Lumbar Spinal Stenosis (LSS). We evaluated the association of a Mediterranean diet (MD), its major food components and ultra-processed food (UPF) with the risk of LSS.

METHODS AND RESULTS

Participants were recruited from the Neurosurgery Department of the IRCCS Neuromed, Italy. The study sample consisted of 156 cases of LSS, and 312 controls matched 1:2 for sex, age (±6 months) and physical activity, without a history or clinical evidence of LSS who were identified from the general population. Adherence to MD was assessed by the Mediterranean Diet Score based on 9 food groups. UPF was defined according to NOVA classification and calculated as the ratio (%) of UPF (g/d) on total food consumed (g/d). In multivariable-adjusted analysis, a 2-point increase in the MD score was not associated with LSS risk (OR: 1.02, 95% CI: 0.72-1.46). An increment of 10 g/d of fruits and nuts, cereals or fish led to lower odds of LSS (OR: 0.97, 95% CI: 0.95-0.99; OR: 0.88, 95% CI: 0.82-0.94; OR: 0.87, 95% CI: 0.76-0.99, respectively). Additionally, 1% increment in the consumption of UPF in the diet was independently associated with higher LSS risk (OR: 1.09, 95% CI: 1.04-1.14).

CONCLUSION

A diet rich in fruits, cereals, fish is associated with lower risk of LSS while a large dietary share of UPF increases the risk of this disease. Further studies with a prospective design and larger sample sizes are warranted.

Hypertrophy of the ligamentum flavum in lumbar spinal canal stenosis is associated with abnormal accumulation of specific lipids

Ligamentum flavum hypertrophy (HLF) is the most important component of lumbar spinal canal stenosis (LSCS). Analysis of hypertrophied ligamentum flavum (HLF) samples from patients with LSCS can be an important que. The current study analyzed the surgical samples of HLF samples in patients with LCSC using quantitative and qualitative high performance-liquid chromatography and mass spectrometry. We collected ligamentum flavum (LF) tissue from twelve patients with LSCS and from four patients with lumbar disk herniation (LDH). We defined LF from LSCS patients as HLF and that from LDH patients as non-hypertrophied ligamentum flavum (NHLF). Total lipids were extracted from the LF samples and evaluated for quantity and quality using liquid chromatography and mass spectrometry. The total lipid amount of the HLF group was 3.6 times higher than that of the NHLF group. Phosphatidylcholines (PCs), ceramides (Cers), O-acyl-ω-hydroxy fatty acids (OAHFAs), and triglycerides (TGs) in the HLF group were more than 32 times higher than those of the NHLF group. PC(26:0)+H+, PC(25:0)+H+, and PC(23:0)+H+ increased in all patients in the HLF group compared to the NHLF group. The thickness of the LF correlated significantly with PC(26:0)+H+ in HLF. We identified the enriched specific PCs, Cers, OAHFAs, and TGs in HLF.

Association between mild cognitive impairment and lumbar degenerative disease in a Japanese community: A cross-sectional study

Lumbar degenerative disease and dementia are increasing in super-aging societies and are both related to physical dysfunction and pain. However, the relationship between these diseases remains unclear. This cross-sectional study aimed to investigate the comorbidity rates of lumbar spinal canal stenosis (LSS) and mild cognitive impairment (MCI) and clarify the association between LSS presence, lumbar symptoms, and quality of life (QOL) related to low back pain and cognitive impairment in the Japanese population. We enrolled 336 participants (men 124; women 212; mean age 72.2 years) from a medical checkup program. LSS was diagnosed using a self-administered questionnaire, and lumbar symptoms were evaluated using the visual analog scale (low back pain, and pain and numbness of the lower limb). QOL related to low back pain was evaluated using the Japanese Orthopedic Association Back-Pain Evaluation Questionnaire (JOABPEQ: pain, and lumbar, and gait function). Radiological lumbar degeneration was classified using Kellgren-Lawrence grading and lateral radiographs of the lumbar spine. Cognitive function was measured using the Mini Mental State Examination (MMSE), and MCI was defined by a summary score of MMSE ≤27. Logistic and multiple linear regression analyses were performed to analyze the association between MCI, summary score of MMSE, and lumbar degenerative disease. The comorbidity rate of MCI and LSS was 2.1%, and the rate of MCI was 41% in participants with LSS. Lumbar function in JOABPEQ was associated with MCI. The presence of LSS and lumbar function in JOABPEQ were associated with MMSE. Over one-third of the people with LSS had MCI. The presence of LSS and deterioration of QOL due to low back pain were related to cognitive impairment. We recommend evaluating cognitive function for patients with LSS because the rate of MCI was high in LSS participants.

The impact of type 2 diabetes on the development of tendinopathy

Tendinopathy is a chronic and often painful condition affecting both professional athletes and sedentary subjects. It is a multi-etiological disorder caused by the interplay among overload, ageing, smoking, obesity (OB) and type 2 diabetes (T2D). Several studies have identified a strong association between tendinopathy and T2D, with increased risk of tendon pain, rupture and worse outcomes after tendon repair in patients with T2D. Moreover, consequent immobilization due to tendon disorder has a strong impact on diabetes management by reducing physical activity and worsening the quality of life. Multiple investigations have been performed to analyse the causal role of the individual metabolic factors occurring in T2D on the development of tendinopathy. Chronic hyperglycaemia, advanced glycation end-products, OB and insulin resistance have been shown to contribute to the development of diabetic tendinopathy. This review aims to explore the relationship between tendinopathy and T2D, in order to define the contribution of metabolic factors involved in the degenerative process and to discuss possible strategies for the clinical management of diabetic tendinopathy.

Strong association of type 2 diabetes with degenerative lumbar spine disorders

Tantalizing connections between type 2 diabetes and degenerative lumbar spine disorders have become increasingly evident. However, the association of type 2 diabetes with degenerative lumbar spine disorders remains unclear. We sought to clarify the association between type 2 diabetes and lumbar spine disorders using nationwide data in Korea. Furthermore, we explored the association of diabetes with the prevalence of spinal procedures. The data in this study was obtained from Korean health claim database. Between 2016 and 2019, totals of 479,680 diabetes and 479,680 age- and sex-matched control subjects were enrolled. Patients with diabetes had more likely to have degenerative lumbar spine disorders and spinal procedures than controls. Using multivariate-adjusted analysis, patients with diabetes were at increased risk of being concomitantly affected by lumbar disc disorder [adjusted odds ratio 1.11 (95% confidence interval 1.10-1.12)], lumbar spondylotic radiculopathy [1.12 (1.11-1.13)], spondylolisthesis [1.05 (1.02-1.08)] and spinal stenosis [1.16 (1.15-1.18)], compared to controls. Furthermore, diabetic patients had an increased risk of undergoing lumbar spinal injection [1.13 (1.12-1.14)], laminectomy [1.19 (1.15-1.23)], and fusion surgery [1.35 (1.29-1.42)]. We demonstrated that type 2 diabetes was significantly associated with lumbar spine disorders and frequent spinal procedures. Our results suggest diabetes as a predisposing factor for lumbar spine disorders.

Association of Lumbar Spinal Stenosis with Severe Disability and Mortality Among Community-Dwelling Older Adults: The Locomotive Syndrome and Health Outcomes in the Aizu Cohort Study

STUDY DESIGN

This prospective cohort study analyzed data from the Locomotive Syndrome and Health Outcomes in the Aizu Cohort Study.

OBJECTIVE

To investigate the association between lumbar spinal stenosis (LSS) and severe disability and mortality among community-dwelling older adults.

SUMMARY OF BACKGROUND DATA

Only a few studies have investigated LSS longitudinally, and the study participants were limited to selected patients diagnosed with LSS during a hospital visit. Additionally, the prognosis of LSS remains unclear.

METHODS

We enrolled independent community-dwelling older adults aged 65 years or older at the time of a baseline health checkup in 2008. LSS was diagnosed using a validated diagnostic support tool for LSS. The primary endpoint was a composite of severe disability (long-term care insurance certification grade 4 or 5) and mortality. We used 1 minus Kaplan-Meier failure estimates and the log-rank test to compare the interval between baseline and the predetermined endpoint as well as a Cox proportional hazards model to estimate hazard ratios (HRs) for the LSS group with adjustment for possible confounders. Multiple imputation by chained equations was performed for sensitivity analysis.

RESULTS

Of 2058 subjects enrolled, 1560 did not have missing covariates; 269 (17%) were diagnosed with LSS. After a median follow-up of 5.8 years, the rates of severe disability and mortality were 0.022 per year in subjects with LSS and 0.012 per year in those without (P = 0.006). The adjusted HR for the composite endpoint in the LSS group was 1.55 (95% confidence interval [CI], 1.01-2.38). A similar association was observed after multiple imputation of missing covariates (adjusted HR, 1.51 [95% CI, 1.06-2.16]).

CONCLUSION

LSS was associated with severe disability and mortality in community-dwelling older adults. Detection of adults with LSS in the community may contribute to local health promotion.Level of Evidence: 2.

Diabetes Mellitus and the Development of Lumbar Canal Stenosis: Is There Any Relevance?

Study Design

Retrospective study.

Purpose

To assess the relationship between the severity of lumbar canal stenosis (LCS) and type-II diabetes mellitus (DM).

Overview of Literature

DM is a multiorgan disorder that has an effect on all types of connective tissues. LCS is a narrowing of the spinal canal with nerve root impingement that causes neurological claudication and radiculopathy. Identification of the risk factors of LCS is key in the prevention of its onset or progression.

Methods

LCS patients were divided into three groups as per DM status: group A without DM (n=150); group B patients with well-controlled DM; and group C patients with uncontrolled DM. Groups B and C were subdivided into group B1: patients with DM with a duration of ≤10 years (n=76), group B2: DM with duration of >10 years (n=68), group-C1 DM duration ≤10 years (n=56), and group C2 DM duration >10 years (n=48). The severity of LCS was evaluated using the Swiss Spinal Stenosis Scale (SSSS) and Modified Oswestry Disability score (MODS). Operated patients ligamentum flavum sent for histological staining and quantitative immunofluorescence analysis.

Results

The demographic data of groups did not show any difference except in age. There was no difference between the mean SSSS and MODS of groups A and B1. Groups B2, C1, and C2 had higher average SSSS and MODS than group A (p<0.05). Groups B2 and C2 had higher SSSS and MODS than groups B1 and C1. Groups C1 and C2 had higher scores than groups B1 and B2 (p<0.05). The severity of LCS was significantly related to the duration of DM in groups B and C (p<0.05). Uncontrolled and longer duration of DM had significant elastin fibers loss and also higher rate of disk apoptosis, high matrix aggrecan fragmentation, and high disk glycosaminoglycan content.

Conclusions

Longer duration and uncontrolled diabetes were risk factors for LCS and directly correlate with the severity of LCS.

Clinical Outcomes of "U" Route Transforaminal Percutaneous Endoscopic Lumbar Discectomy in Chronic Pain Patients with Lumbar Spinal Stenosis Combined with Disc Herniation

Introduction

“U” route transforaminal percutaneous endoscopic lumbar discectomy (PELD) was introduced for lumbar spinal stenosis (LSS) combined with disc herniation (DH) treatment. This study aims to explore the efficacy and safety of “U” route PELD on chronic pain patients with LSS combined with DH.

Methods

Degenerative LSS combined with DH patients who underwent “U” route PELD were reexamined, and 80 patients were recruited and followed up for 2 years. The other 80 healthy individuals who were age- and sex-matched to the patients without chronic pain were enrolled as healthy controls. Minimum dura sac cross-sectional area (mDCSA) by MRI, Visual Analog Scale (VAS), Oswestry Disability Index (ODI), and modified MacNab outcomes were assessed. Emotional evaluation of pain catastrophizing and depression was documented with Pain Catastrophizing Scale (PCS) and Beck Depression Inventory (BDI), respectively, for patients before and after surgery and healthy individuals.

Results

All patients were of the age range from 47 to 85 years, with an average of 59.5 ± 9.76 years. Symptoms duration was 114.6 ± 22.77 months, operation time was 87.7 ± 25.20 minutes, and the average hospital stay was 5.8 ± 2.81 days. Four patients quit, and hence, a total of 76 patients completed the follow-up. The results indicated that mDCSA was improved significantly after operation (p < 0.001), either low back and leg VAS or ODI decreased over time (p < 0.001), and the excellent-to-good rate was improved from 88.75% to 93.42% during postoperative 2 years (p < 0.05). Complications of dural tear, nerve root, or dysesthesia were reported in 5 patients, and all recovered after conservative therapy. The scores of pain catastrophizing were reduced after operation (p < 0.001), but no significance of BDI was found between patients and healthy controls (p > 0.05).

Conclusions

The “U” route PELD seems an alternative to LSS combined with DH treatment, which might reach a better decompression and effectively improve chronic pain conditions. Still, the complications were potential and required further consideration.

Canine models of spine disorders

Neck and low back pain are common among the adult human population and impose large social and economic burdens on health care and quality of life. Spine-related disorders are also significant health concerns for canine companions with etiopathogeneses, clinical presentations, and diagnostic and therapeutic options that are very similar to their human counterparts. Historically, induced and spontaneous pathology in laboratory rodents, dogs, sheep, goats, pigs, and nonhuman primates have been used for study of human spine disorders. While each of these can serve as useful preclinical models, they all have inherent limitations. Spontaneously occurring spine disorders in dogs provide highly translatable data that overcome many of the limitations of other models and have the added benefit of contributing to veterinary healthcare as well. For this scoping review, peer-reviewed manuscripts were selected from PubMed and Google Scholar searches using keywords: "intervertebral disc," "intervertebral disc degeneration," "biomarkers," "histopathology," "canine," and "mechanism." Additional keywords such as "injury," "induced model," and "nucleus degeneration" were used to further narrow inclusion. The objectives of this review were to (a) outline similarities in key features of spine disorders between dogs and humans; (b) describe relevant canine models; and (c) highlight the applicability of these models for advancing translational research and clinical application for mechanisms of disease, diagnosis, prognosis, prevention, and treatment, with a focus on intervertebral disc degeneration. Best current evidence suggests that dogs share important anatomical, physiological, histological, and molecular components of spinal disorders in humans, such that induced and spontaneous canine models can be very effective for translational research. Taken together, the peer-reviewed literature supports numerous advantages for use of canine models for study of disorders of the spine when the potential limitations and challenges are addressed.

Hyperglycemia and its influence on development of lumbar degenerative disc disease

Study Design

Objectives

Methods

Results

Conclusions

Ligamentum flavum fibrosis and hypertrophy: Molecular pathways, cellular mechanisms, and future directions

Hypertrophy of ligamentum flavum (LF), along with disk protrusion and facet joints degeneration, is associated with the development of lumbar spinal canal stenosis (LSCS). Of note, LF hypertrophy is deemed as an important cause of LSCS. Histologically, fibrosis is proved to be the main pathology of LF hypertrophy. Despite the numerous studies explored the mechanisms of LF fibrosis at the molecular and cellular levels, the exact mechanism remains unknown. It is suggested that pathophysiologic stimuli such as mechanical stress, aging, obesity, and some diseases are the causative factors. Then, many cytokines and growth factors secreted by LF cells and its surrounding tissues play different roles in activating the fibrotic response. Here, we summarize the current status of detailed knowledge available regarding the causative factors, pathology, molecular and cellular mechanisms implicated in LF fibrosis and hypertrophy, also focusing on the possible avenues for anti-fibrotic strategies.

Amyloid protein aggregation in diabetes mellitus accelerate intervertebral disc degeneration

Diabetes is one of the risk factors for disc degeneration, but the exact mechanism is still unclear. Misfolding and aggregation of human islet amyloid polypeptide (hIAPP) is an important factor in diabetes. hIAPP proteins misfold from monomers to β-sheet-rich oligomers, destroy the permeability of the cell membrane and cause abnormal cell function and death. Under the pathological state of diabetes, hIAPP oligomers can promote the expression and secretion of the inflammatory factor IL-1β, while IL-1β-mediated inflammatory response is the pathogenesis basis of intervertebral disc degeneration. Thus, amyloid hIAPP aggregation accelerates disc degeneration in the pathological state of diabetes.

Osteoarthritis and type 2 diabetes: From pathogenetic factors to therapeutic intervention

Over the last decades, osteoarthritis (OA) and type 2 diabetes (T2D) prevalence increased due to the global ageing population and the pandemic obesity. They currently affect a substantial part of the Western world population and are characterized by enhancing the risk of disability and reduction of quality of life. OA is a multifactorial condition whose development derives from the interaction between individual and environmental factors: The best known primarily include age, female gender, genetic determinants, articular biomechanics, and obesity (OB). Given the high prevalence of OA and T2D and their association with OB and inflammation, several studies have been conducted to investigate the causative role of biological characteristics proper to T2D on the development of OA. This review aims to analyse the relationship between of OA and T2D, in order to explain the pathophysiological drivers of the degenerative process and to delineate possible targets to which appropriate treatments may be addressed in the near future.

Intervertebral disc degeneration: A focus on obesity and type 2 diabetes

Obesity (OB) and type 2 diabetes (T2D) are among the most prevalent metabolic diseases. They currently affect a substantial part of the world population and are characterized by several systemic co-morbidities, including cardiovascular diseases, stroke, cancer, liver steatosis, and musculoskeletal disorders, by increasing the risk of developing osteoarthritis and intervertebral disc degeneration (IVDD). IVDD is a chronic, progressive process whose main features are disc dehydration, loss of disc height, and changes of load distribution across the spine, resulting in disc structure disruption and leading to low back pain onset. Given the high prevalence of these metabolic disorders and their association with IVDD, several studies have been conducted in order to investigate the causative role of biological and biomechanical characteristics proper to these conditions in the development of IVDD. This review aims to analyse the role of OB and T2D on IVDD, in order to clarify the pathophysiological drivers of the degenerative process and to delineate possible targets to which appropriate treatments may be addressed in the near future.

Increased advanced glycation end products in hypertrophied ligamentum flavum of diabetes mellitus patients

BACKGROUND CONTEXT

Ligamentum flavum (LF) hypertrophy plays a dominant role in lumbar spinal stenosis (LSS). Although LSS prevalence is known to be higher in patients with diabetes mellitus (DM), the underlying pathomechanisms are not well understood. Abnormal advanced glycation end products (AGEs) formation occurs in DM and promotes tissue damage in various organs through degeneration and inflammation.

PURPOSE

To analyze and compare LF histology focused on AGE status between control patients, LSS patients with DM, and LSS patients without DM.

STUDY DESIGN/SETTING

Basic research study design utilizing human LF tissue for histologic analyses.

PATIENT SAMPLE

LF tissue samples were collected from patients who underwent lumber decompression surgery for LSS in the author's institution.

OUTCOME MEASURES

Quantitative visualization of Masson's Trichrome (MT) stains, and AGE immunohistochemistry (IHC) for the three groups.

METHODS

Ten LF specimens from LSS patients with DM (DM group, mean age 71.4 years), 10 from LSS patients without DM (non-DM group, mean age 71.2 years), and 9 from patients with lumbar disc herniation or cauda equina tumor (control group, mean age 49.0 years) were harvested during surgery and histologically analyzed. Percentage of elastic fiber areas (%EF) was measured with MT staining, and the percentage of AGE immuno-positive areas (%AGEs) was measured with IHC.

RESULTS

The average %EFs were 12.8 in the DM group, 17.1 in the non-DM group, and 24.9 in the control group. The decrease in the elastic fibers was significantly more in the DM group than in the non-DM (p<.01) and control groups (p<.001). Accumulation of AGEs was found mainly in the extracellular matrix in areas of elastic fiber disruption. The %AGEs were 18.3 in the DM group, 12.1 in the non-DM group, and 4.6 in the control group. These were significantly larger in the DM group than in the non-DM (p<.01) and control (p<.01) groups. The %AGEs also positively correlated with patient age (p<.01, R=0.47).

CONCLUSIONS

Accumulation of AGEs is significantly greater in the LF of DM patients and correlates with patient age. AGEs may accelerate degeneration and hypertrophy of LF with age and may lead to higher prevalence of LSS in patients with DM.

CLINICAL SIGNIFICANCE

The present results partly reveal the molecular mechanism of LF hypertrophy, suggesting that AGEs may be involved in the process of LF degeneration in the elderly and patients with DM.

The Sirt1/P53 Axis in Diabetic Intervertebral Disc Degeneration Pathogenesis and Therapeutics

Intervertebral disc degeneration (IDD) is one of the major causes of low back pain. Diabetes is a risk factor for IDD and may aggravate IDD in rats; however, the mechanism is poorly understood. Previously, we demonstrated that apoptosis and senescence were increased in diabetic nucleus pulposus (NP) tissues; in the current study, we found that hyperglycaemia may promote the incidence of apoptosis and senescence in NP cells in vitro. Meanwhile, the acetylation of P53, a master transcription factor of apoptosis and senescence, was also found increased in diabetic NP tissues in vivo as well as in hyperglycaemic NP cells in vitro. Sirt1 is an NAD⁺-dependent deacetylase, and we showed that the expression of Sirt1 was decreased in NP tissues, while hyperglycaemia could suppress the expression and activity of Sirt1 in NP cells. Furthermore, we demonstrated that butein may inhibit acetylation of P53 and protect NP cells against hyperglycaemia-induced apoptosis and senescence through Sirt1 activation, as the Sirt1 inhibitor Ex527 may counteract the protective effect of butein in hyperglycaemic NP cells. An in vivo study showed that butein could ameliorate the IDD process in diabetic rats, while Sirt1 was increased and acetyl-p53 was decreased in NP tissues in butein-treated rats. These results indicate that the Sirt1/P53 axis is involved in the pathogenesis of diabetic IDD and may serve as a therapeutic target for diabetic IDD.

Molecular profile of ultrastructure changes of the ligamentum flavum related to lumbar spinal canal stenosis

Lumbar spinal canal stenosis (LSCS) is a degenerative disease observed by hypertrophy of the ligamentum flavum (LF) that cause compression of the lumbar neural content. Diabetes mellitus (DM) is a risk factor for the disease and we have shown previously that DM increases the fibrosis and elastic fiber loss in patients with LSCS. The purpose of this study was to find the proteins that play a role in the development of this clinical pathogenesis and the effect of DM on protein expression. LF tissue retrieved from patients diagnosed with LSCS, some were also diagnosed with DM, were compared with LF from patients diagnosed with herniated nucleus pulposus (HNP). The tissues were analyzed by mass spectrometry for proteins profile alteration. We found that LF of LSCS/DM patients exhibited significantly higher levels of proteoglycan proteins and latent transforming growth factor β-binding protein (LTBP2 and LTBP4). Additionally, an increase of HTRA serine protease 1 and insulin-like growth factor binding protein-5 were noted. The higher fibrosis was also associated with proteins related to inflammation and slower tissue repair. Collagen 6 and transforming growth factor inhibitor are related to activation of the anti-inflammatory M2 pathway that is associated with tissue repair. The decrease of these proteins expression in LSCS/DM is associated with increased levels and activation of M1 pro-inflammatory pathways. Interestingly, C3 and C4b members of the complement complex and mannose receptor-like protein (CLEC18) paralogous proteins were detectable solely at the LSCS/DM patients' samples. Histology analysis shows that inflammatory was induced by the hyperglycemic conditions in diabetic patients involve in altering the matrix compositions. Thus, the protein profiles associated with inflammatory pathways affecting the LF suggested increasing susceptibility of developing the degeneration under hyperglycemic conditions.

Diabetes mellitus as a risk factor for intervertebral disc degeneration: a critical review

PURPOSE

To examine to what extent diabetes mellitus (DM) is implicated as a distinct mechanism in intervertebral disc degeneration (IVDD).

METHODS

The published clinical and laboratory data relevant to this matter are critically reviewed. A total of 12 clinical studies evaluate the association between DM and degenerative changes such as IVDD, spinal stenosis (SS) and IVD herniation. A total of 34 laboratory research papers evaluate the association between DM and IVDD.

RESULTS

There are 7 studies that correlate DM with IVDD, 4 of them showing that DM is a significant risk factor for degeneration, and 3 of them failing to establish any association. Three studies demonstrate significant association between DM and SS. However, 2 of these studies also include patients with IVD herniation that failed to demonstrate any correlation with DM. Two other studies indicate a significant association between DM and lumbar disc herniation. Multiple different mechanisms, acting independently or interactively, cause tissue damage leading to IVDD including: microangiopathy of the subchondral vertebral endplate, cellular senescence, cell death (through apoptosis or autophagy), hyperglycaemia, advance glycation end products, adipokines, and cytokines (through oxidative, osmotic, and inflammatory mechanisms).

CONCLUSION

The clinical evidence is not consistent, but weakly supports the relationship between DM and IVDD. However, the laboratory studies consistently suggest that DM interferes with multipronged aberrant molecular and biochemical pathways that provoke IVDD. Taken as a whole, the strong laboratory evidence and the weak clinical studies implicate DM as a distinct contributing factor for IVDD. These slides can be retrieved under Electronic Supplementary Material.

Influence of diabetes mellitus on patients with lumbar spinal stenosis: A nationwide population-based study

Purpose

To evaluate the relationship between comorbidities, medical cost, and surgical outcome in patients with lumbar spinal stenosis (LSS) and diabetes mellitus (DM).

Methods

Data on patients with LSS (n = 14,298) were collected from the Korean National Health Insurance Service database from 2005 to 2007. After 8 years of follow-up, a “DM group” (n = 3,478) and a “non-DM group” (n = 10,820) were compared according to outcome measures. Cox proportional hazard regressions were performed to examine the relationship between DM, hypertension (HTN), cardiovascular disease (CVD), chronic kidney disease (CKD), cerebrovascular disease (CbVD), and surgery for LSS. The admission rate and medical cost as well asthe overall survival rate for those who underwent lumbar surgery were also assessed among patients with DM and LSS.

Results

Mortality was about 1.35 times higher in the DM group than in the non-DM group. Patients with DM and comorbidities including HTN (hazard ratio [HR], 1.40; 95% confidence interval [CI], 1.25–1.56; p<0.001), CVD (HR, 1.53; 95% CI, 1.36–1.73; p<0.001), CKD (HR, 3.18; 95% CI, 2.7–3.76; p<0.001), and CbVD (HR, 1.69; 95% CI, 1.49–1.91; p<0.001) showed an increased risk of mortality. The mean hospitalization time and average medical cost of patients with DM who underwent lumbar surgery were 60.8 days, and 7,127 USD, respectively. This was 31.3 days longer, and 6,207 USD higher, respectively, than those of patients with DM who underwent conservative treatment for LSS. Within the DM group, the survival rate of surgical management of LSS had a significant tendency for positive prognosis compared with those administered conservative treatment (p = 0.046).

Conclusions

In patients with LSS, DM was associated both with poor prognosis (most significantly in those with CKD), and increased medical cost in those who underwent surgery. Nevertheless, surgical treatment for LSS in patients with DM was related to favorable prognosis compared with conservative treatment.

Is there an association between diabetes and neck and back pain? A systematic review with meta-analyses

Background and objective

Approximately half of the population will experience either low back pain or neck pain, at some point in their lives. Previous studies suggest that people with diabetes are more likely to present with chronic somatic pain, including shoulder, knee and spinal pain. This study aimed to systematically review and appraise the literature to explore the magnitude as well as the nature of the association between diabetes and back, neck, or spinal (back and neck) pain.

Databases and data treatment

A systematic search was performed using the Medline, CINAHL, EMBASE, and Web of Science electronic databases. Studies which assessed the association between diabetes and back or neck pain outcomes, in participants older than 18 years of age were included. Two independent reviewers extracted data on the incidence of pain and reported associations.

Results

Eight studies were included in the meta-analyses. Meta-analyses showed that people with diabetes are more likely to report low back pain [5 studies; n: 131,431; odds ratio (OR): 1.35; 95% Confidence Interval (CI): 1.20 to 1.52; p<0.001] and neck pain (2 studies; n: 6,560; OR: 1.24; 95% CI: 1.05 to 1.47; p = 0.01) compared to those without diabetes. Results from one longitudinal cohort study suggested that diabetes is not associated with the risk of developing future neck, low back or spinal pain.

Conclusions

Diabetes is associated with low back and neck individually, and spinal pain. The longitudinal analysis showed no association between the conditions. Our results suggest that diabetes co-exists with back pain; however, a direct causal link between diabetes and back pain was not established.

Systematic review registration

PROSPERO registration CRD42016050738.

The effect of diabetes on perioperative complications following spinal surgery: a meta-analysis

Background

Degenerative spinal diseases and diabetes mellitus (DM) have increasingly become a social and economic burden. The effect of DM on spinal surgery complications reported by previous studies remains controversial.

Methods

We searched MEDLINE, Cochrane CENTRAL, ScienceDirect, EMBASE, and Google Scholar to identify studies reporting the relationship between DM and spinal surgery complications. Two independent reviewers performed independent data abstraction. The I2 statistic was used to assess heterogeneity. A fixed-effects or random-effects model was used for the meta-analysis.

Results

Twenty-four studies met the inclusion criteria. Surgical site infection and the incidence of deep venous thrombosis after spinal surgery were significantly higher in patients with than in patients without diabetes, and the length of hospital stay was significantly longer in patients with diabetes (P<0.05). No significant differences were observed in the risk of reoperation, blood loss, and operation time between patients with and those without diabetes (P.0.05).

Conclusion

Patients with diabetes have a higher risk when undergoing spinal surgery than patients without diabetes. Diabetes increases the risks of postoperative mortality, surgical site infection, deep venous thrombosis, and a prolonged hospitalization time after spinal surgery.

Minimally invasive spinal decompression surgery in diabetic patients: perioperative risks, complications and clinical outcomes compared with non-diabetic patients' cohort

BACKGROUND

Prior studies have documented an increased complication rate in diabetic patients undergoing spinal surgery. However, the impact of diabetes on the risk of postoperative complications and clinical outcome following minimally invasive spinal (MIS) decompression is not well understood.

OBJECTIVES

To compare complication rates and outcomes of MIS decompression in diabetic patients with a cohort of non-diabetic patients undergoing similar procedures.

METHODS

Medical records of 48 patients with diabetes and 151 control patients that underwent minimally invasive lumbar decompression between April 2009 and July 2014 at our institute were reviewed and compared. Past medical history, the American Society of Anesthesiologists score, perioperative mortality, complication and revision surgeries rates were analyzed. Patient outcomes included: the visual analog scale and the EQ-5D scores.

RESULTS

The mean age was 68.58 ± 11 years in the diabetic group and 51.7 ± 17.7 years in the control group. No major postoperative complications were recorded in either group. Both groups were statistically equivalent in their postoperative length of stay, minor complications and revision rates. Both groups showed significant improvement in their outcome scores following surgery.

CONCLUSIONS

Our results indicate that minimally invasive decompressive surgery is a safe and effective treatment for diabetic patients and does not pose an increased risk of complications. Future prospective studies are necessary to validate the specific advantages of the minimally invasive techniques in the diabetic population. These slides can be retrieved under Electronic Supplementary Material.

Factors associated with lumbar spinal stenosis in a large-scale, population-based cohort: The Wakayama Spine Study

Objective

Patients with lumbar spinal stenosis (LSS) who have radiographically similar degrees of stenosis may not necessarily exhibit equivalent symptoms. As part of a cross-sectional study, we examined factors associated with symptomatic LSS (sLSS) in the general population of Japan.

Methods

We evaluated 968 participants (men, 319; women, 649) between 2008 and 2010. Orthopedic surgery specialists diagnosed sLSS using interview results, medical examinations, and imaging findings. LSS was radiographically graded using a 4-level scale. Additionally, we examined basic anthropometry, smoking habits, alcohol consumption, ankle-brachial index values (ABI), and glycosylated hemoglobin (HbA1c) levels. We grouped patients with moderate and severe radiographic LSS, and compared the indicated factors on the basis of the presence/absence of sLSS. Data were evaluated using multiple logistic regression analyses.

Results

Radiographically, 451 participants had moderate and 288 severe stenosis. Clinically, 92 participants were diagnosed with sLSS, including 36 with moderate and 52 with severe stenosis. In the moderate stenosis group, participants with sLSS had significantly higher rates of diabetes mellitus (DM) and lower ABIs than did non-LSS participants. Although sLSS participants tended to be older (p = 0.19), there were no significant differences in the sex distribution, body mass index values, or in the percentages of participants who were drinkers/smokers. In the severe stenosis group, there were no differences in any of the evaluated factors. Multiple logistic regression showed that DM (odds ratio [OR], 3.92; 95% confidence interval [CI], 1.52–9.34]) and low ABI (1 SD = 0.09; OR, 1.36; 95% CI, 1.04–1.81) were significantly associated with LSS in the moderate stenosis group.

Conclusions

DM and low ABIs are significantly associated with sLSS in patients with moderate radiographic stenosis. Neither factor is associated with sLSS in patients with severe stenosis. Notably, the effects of intrinsic factors on symptomology may be masked when anatomic stenosis is severe.

The Difference in Gender Affects the Pathogenesis of Ligamentum Flavum Hypertrophy

Introduction

Gender differences may play a role in the pathogenesis of lumbar spinal stenosis. However, few reports that discuss the effects of gender differences in ligamentum flavum (LF) hypertrophy have been published, and no study has investigated the relationship between LF thickness and the quantitative value of intervertebral disc (IVD) degeneration. This study aimed to investigate the impact of gender on the pathomechanisms underlying LF hypertrophy, focusing on the relationship among LF thickness, IVD degeneration, and age.

Methods

The subjects include 100 patients with low back pain and leg numbness, tingling, or pain. We measured LF thickness and the T2 values of IVDs using MR imaging and analyzed the relationship among LF thickness, T2 values of IVDs, and age. The interclass correlation coefficient (ICC) was calculated as the inter-rater reliability between the LF thickness values measured by two investigators.

Results

ICC was calculated for the two measurements of LF thickness (r = 0.923, 95% CI: 0.907-0.936). No statistically significant difference in the T2 values of IVDs was observed between females and males from L2/3 to L5/S. There were significantly negative linear correlations between LF thickness and the T2 values of IVDs at all levels, but this correlation was not observed in females at L4/5. There were significantly negative linear correlations between age and the T2 values of IVDs from L2/3 to L5/S for all patients, females, and males (r = 0.422-0.756). In addition, there were significantly positive linear correlations between age and LF thickness from L2/3 to L4/5 for all patients (r = 0.329-0.361) and females (r = 0.411-0.481). Correlations were not observed for males at all levels or for all patients at L5/S.

Conclusions

The relationships identified among LF thickness, age, and IVD degeneration suggest that gender differences play a role in the pathogenesis of LF hypertrophy.

Quantitative Evaluation of Vertebral Microvascular Permeability and Fat Fraction in Alloxan-induced Diabetic Rabbits

Purpose To determine longitudinal relationships between lumbar vertebral bone marrow permeability and marrow adipose tissue in a rabbit diabetes model by using quantitative dynamic contrast agent-enhanced (DCE) magnetic resonance (MR) imaging and iterative decomposition of water and fat with the echo asymmetry and least-squares estimation quantitation (IDEAL IQ) sequence. Materials and Methods Twenty rabbits were randomly assigned to the diabetic (n = 10) or control (n = 10) group. All rabbits underwent sagittal MR imaging of the lumbar region at fixed time points (0, 4, 8, 12, and 16 weeks after alloxan injection). A linear mixed-effects model was used to analyze fat fraction (FF) and permeability parameter changes for 16 months after baseline. These parameters were compared between the two groups by using an independent-samples t test. Correlation of DCE MR imaging parameters with FF and with microvessel density (MVD) was analyzed by using the Spearman correlation coefficient. All statistical analyses were performed with software. Results Twelve weeks after injection, transfer constant (K^trans) and rate constant (K_ep) were markedly and significantly increased, while fractional plasma volume (V_p) significantly decreased. The volume of extravascular extracellular space (V_e) decreased significantly after 16 weeks in the diabetic group. MVD was negatively correlated with K^trans and K_ep and positively correlated with V_e and V_p, while FF was positively correlated with K^trans and K_ep and negatively correlated with V_e and V_p (P < .05 for all). Conclusion DCE MR imaging and the IDEAL IQ sequence can be used for quantitative evaluation of changes in vertebral microvascular permeability and vertebral fat deposition in alloxan-induced diabetic rabbits. This variation is highly associated with increased vertebral fat deposition. ^© RSNA, 2017 Online supplemental material is available for this article.

Diabetes mellitus is associated with increased elastin fiber loss in ligamentum flavum of patients with lumbar spinal canal stenosis: results of a pilot histological study

PURPOSE

Lumbar spinal canal stenosis (LSCS) is associated with fibrosis, decreased elastin-to-collagen ratio, and hypertrophy of the ligamentum flavum (LF). Diabetes mellitus (DM) is known to cause metabolic disturbances within the extracellular matrix in multiple tissues. These alterations may play a major role in the severity of clinical symptoms of LSCS affecting diabetic patients. We aimed to examine the hypothesis that DM may contribute to the LF changes seen in patients with LSCS.

METHODS

The study cohort included 29 patients: 23 with LSCS (10 with DM vs. 13 without DM) as well as six patients with lumbar disc herniation (LDH). Surgical LF specimens were retrieved for histological assessment. Morphologic quantification of confocal microscopy images using fast Fourier transform analysis allowed us to compare anisotropy and elastin fiber orientation between groups.

RESULTS

There was a significant positive correlation between fasting plasma glucose values and degree of elastin degradation (r = 0.36, p = 0.043). The diabetic patients with LSCS showed a significantly greater loss of elastic fibers (2.3 ± 0.9 vs. 1.5 ± 0.55, p = 0.009), although fibrosis was shown to be similar (1.44 ± 0.7 vs. 1.43 ± 0.88, p = 0.98). There was no significant difference in the degree of calcification in the LSCS group between patients with and without diabetes (1.71 vs. 2.05%, p = 0.653). Fiber orientation was found to be less homogenous in the LSCS compared with the LDH group, although not significantly affected by DM.

CONCLUSIONS

The present study points to a significant contribution of DM to the loss of elastin fibers that occurs in the LF of patients with LSCS.