MRI evaluation of lumbar disc degenerative disease

Sodium MRI of the Lumbar Intervertebral Discs of the Human Spine: An Ex Vivo Study

BACKGROUND

Lower back pain affects 75%-85% of people at some point in their lives. The detection of biochemical changes with sodium (23Na) MRI has potential to enable an earlier and more accurate diagnosis.

PURPOSE

To measure 23Na relaxation times and apparent tissue sodium concentration (aTSC) in ex-vivo intervertebral discs (IVDs), and to investigate the relationship between aTSC and histological Thompson grade.

STUDY TYPE

Ex-vivo.

SPECIMEN

Thirty IVDs from the lumbar spines of 11 human body donors (4 female, 7 male, mean age 86 ± 8 years).

FIELD STRENGTH/SEQUENCE

3 T; density-adapted 3D radial sequence (DA-3D-RAD).

ASSESSMENT

IVD 23Na longitudinal (T1), short and long transverse (T2s* and T2l*) relaxation times and the proportion of the short transverse relaxation (ps) were calculated for one IVD per spine sample (11 IVDs). Furthermore, aTSCs were calculated for all IVDs. The degradation of the IVDs was assessed via histological Thompson grading.

STATISTICAL TESTS

A Kendall Tau correlation (τ) test was performed between the aTSCs and the Thompson grades. The significance level was set to P < 0.05.

RESULTS

Mean 23Na relaxation parameters of a subset of 11 IVDs were T1 = 9.8 ± 1.3 msec, T2s* = 0.7 ± 0.1 msec, T2l* = 7.3 ± 1.1 msec, and ps = 32.7 ± 4.0%. A total of 30 IVDs were examined, of which 3 had Thompson grade 1, 4 had grade 2, 5 had grade 3, 5 had grade 4, and 13 had grade 5. The aTSC decreased with increasing degradation, being 274.6 ± 18.9 mM for Thompson grade 1 and 190.5 ± 29.5 mM for Thompson grade 5. The correlation between whole IVD aTSC and Thompson grade was significant and strongly negative (τ = -0.56).

DATA CONCLUSION

This study showed a significant correlation between aTSC and degenerative IVD changes. Consequently, aTSC has potential to be useful as an indicator of degenerative spinal changes.

EVIDENCE LEVEL

2 TECHNICAL EFFICACY: Stage 1.

Role of Magnetic Resonance Spectroscopy and T2 Relaxometry as Imaging Biomarker of Early Lumbar Intervertebral Disc Degeneration

STUDY DESIGN

Observational comparative study.

OBJECTIVE

To study the role of magnetic resonance spectroscopy (MRS) and T2 relaxometry (T2r) as imaging biomarkers for identifying early lumbar disc degeneration.

METHODS

We evaluated 236 discs in normal volunteers and 215 discs in low back pain (LBP) patients by MRS and T2r to document the molecular spectra of various metabolites as well as disc hydration and collagen content, respectively. All volunteer discs were Pfirrmann grade 1 (PF1), whereas patients with LBP had PF 1 (n = 156) and PF 2 (n = 59). The study population was compared in three age groups: A (20-30 years), B (30-40 years), and C (40-50 years).

RESULTS

T2r, an indicator of collagen and hydration, was higher in volunteers (121.8 ± 31.1), compared to PF 1 patients (110.68 ± 23.96) and PF 2 patients (90.15 ± 25.81) (P = 0.001). Proteoglycan assessed by MRS was more stable for volunteers (3.39 ± 1.69) and PF 1 patients (3.6 ± 1.69) but reduced in PF 2 patients (2.86 ± 1.47), showing that structural molecules did not alter within the PF 1. However, lactate and other metabolites showed a difference even within PF1 between volunteers and LBP patients. We were able to identify a unique subset of PF 1 that had a normal value of proteoglycan and T2r but altered metabolite distribution, which may represent early disc degeneration (DD).

CONCLUSION

MRS and T2r can be used as imaging biomarkers for early DD by identifying altered metabolic activity with an intact matrix.

Defining a Critical Partition Zone for Sagittal Alignment in Lumbar Spine Fusion Surgery: A Systematic Review

BACKGROUND

Sagittal alignment in the lumbar spine is essential for spinal stability and functionality, with significant implications in surgical planning for spinal deformity correction. However, standardized lumbar partitioning, particularly identifying a critical sagittal alignment zone, remains underdefined. This study aims to establish a reliable lumbar partition to guide surgical decisions and optimize clinical outcomes.

METHODS

A systematic review of four major biomedical databases yielded 32 studies, of which 4 met the inclusion criteria. Studies on asymptomatic adults with segmental lordosis data stratified by pelvic incidence were analyzed. Lumbar lordosis values were converted to percentages, allowing for cross-study comparison. Sensitivity analysis and bias assessment were performed to ensure methodological rigor.

RESULTS

The findings identified the L3-L5 interval, especially around the L4 vertebra, as a critical biomechanical zone across various populations and pelvic incidence groups. Individuals with higher pelvic incidence had concentrated lordosis in lower segments, while those with lower pelvic incidence had greater lordosis in upper segments, underscoring the L3-L5 region's stability as a surgical reference.

CONCLUSIONS

The L3-L5 interval serves as a key partition zone for sagittal alignment, providing a stable reference for lumbar spine fusion. These findings offer a foundational clinical reference, potentially improving alignment outcomes and reducing postoperative complications.

18F-Fluorodeoxyglucose (18F-FDG) PET/CT Appearance of Baastrup's Disease and Its Multimodality Correlation

Baastrup's disease (BD), commonly known as "kissing spine syndrome," presents a significant cause of lower back pain, predominantly affecting the lumbar region. Diagnosis is often challenging due to its symptomatology and radiographic presentation. Herein, we present a case series demonstrating the utility of 18F-fluorodeoxyglucose positron emission tomography/computed tomography (18F-FDG PET/CT) in diagnosing BD accurately, particularly in oncologic settings where it may mimic metastatic lesions. Through a series of cases, we demonstrate the distinctive imaging features of BD on 18F-FDG PET/CT and its differentiation from malignancies. In addition, we emphasize the importance of clinical awareness and proper correlation with CT or MRI to avoid misinterpretation. Furthermore, we discuss the pathophysiology, clinical presentation, and diagnostic modalities of BD, highlighting its underdiagnosis and potential to mimic metastasis on imaging. By enhancing recognition of BD's appearance on 18F-FDG PET/CT, this study aims to prevent misdiagnoses, reduce unnecessary investigations, and ultimately improve patient care in oncologic practice.

A fully automatic MRI-guided decision support system for lumbar disc herniation using machine learning

Background

Normalized decision support system for lumbar disc herniation (LDH) will improve reproducibility compared with subjective clinical diagnosis and treatment. Magnetic resonance imaging (MRI) plays an essential role in the evaluation of LDH. This study aimed to develop an MRI-based decision support system for LDH, which evaluates lumbar discs in a reproducible, consistent, and reliable manner.

Methods

The research team proposed a system based on machine learning that was trained and tested by a large, manually labeled data set comprising 217 patients' MRI scans (3255 lumbar discs). The system analyzes the radiological features of identified discs to diagnose herniation and classifies discs by Pfirrmann grade and MSU classification. Based on the assessment, the system provides clinical advice.

Results

Eventually, the accuracy of the diagnosis process reached 95.83%. An 83.5% agreement was observed between the system's prediction and the ground-truth in the Pfirrmann grade. In the case of MSU classification, 95.0% precision was achieved. With the assistance of this system, the accuracy, interpretation efficiency and interrater agreement among surgeons were improved substantially.

Conclusion

This system showed considerable accuracy and efficiency, and therefore could serve as an objective reference for the diagnosis and treatment procedure in clinical practice.

Venous Anomalies Complicating Anterior Lumbar Interbody Fusion Exposures

The effects of anomalous vasculature impeding optimal exposure to an anterior lumbar interbody fusion approach are limited in literature. We present five individual, unique cases of vascular anomalies in patients undergoing two-stage anterior-posterior lumbar interbody fusion. Cases 1, 2, 4, and 5 have yet to be described in literature in context of anterior lumbar interbody fusions. Case 3 presents anomalous vasculature that has only been described in two other case reports. Case 1 presents the right internal iliac vein originating from the left common iliac vein which was transected for L4-L5 vertebral disc exposure. Case 2 presents the left internal iliac vein originating from the right common iliac vein which required an oblique approach. Case 3 presents a duplicated inferior vena cava that was taken into account but did not interfere with the anterior retroperitoneal approach. Case 4 presents large osteophytes adhering to the left common iliac vein which limited safe dissection and mobilization. Case 5 presents the left internal iliac vein with a high takeoff spanning across the L5-S1 vertebral disc space and requiring transection. This case series highlights the need for preoperative imaging and a working detailed knowledge of anatomy to avoid damaging vasculature that can potentially lead to fatal consequences. The information given in this case series should inform both spine and vascular surgeons on proper preoperative planning. To maximize operative efficiency and safety, spine surgeons and vascular surgeons should collaborate to minimize surgical complications.

Are there any correlations among the number of discopathy levels and pain intensity or disability in patients with symptomatic low back pain?

INTRODUCTION

Low back pain (LBP) is considered a civilization disease that affects people in an increasing number. Discopathy (degeneration of intervertebral discs) is recognised as one of LBP causes. Still, the relationship between the number of discopathy levels and LBP remains unclear. The aim of this study was to evaluate the correlation between the number of discopathy levels with intensity of LBP, functional level and the degree of disability.

MATERIALS AND METHODS

The prospective, cohort study involved 200 patients aged 27 to 55 years (44.9 ± 9.2 years) with single- or multilevel lumbar discopathy confirmed by imaging examinations. Functional examination included NRSscale, goniometric measurements, Modified Laitinen Pain Questionnaire, Oswestry Disability Index and Back Pain Function Scale.

RESULTS

There were statistically significant positive correlations between the number of discopathy levels and the age of the subjects (r = 0.266; p = 0.000), BMI (r = 0.158; p = 0.029) and ODI (r = 0.157; p = 0.026). Positive correlation (r = 0.142; p = 0.044) was also observed between the results of Fingertip-to-floortest and the number of levels of discopathy.

CONCLUSIONS

The number of levels of discopathy was depended on the age and BMI of the patients. It had no effect on pain intensity, range of rotational motion of the lumbar spine and functional status of patients. As the number of levels of discopathy increased, a higher degree of everyday disability was observed.

The association between low virulence organisms in different locations and intervertebral disc structural failure: A meta-analysis and systematic review

Many factors may trigger intervertebral disc (IVD) structural failure (intervertebral disc degeneration (IDD) and endplate changes), including inflammation, infection, dysbiosis, and the downstream effects of chemical factors. Of these, microbial diversity in the IVD and elsewhere in the body has been considered as one of the potential reasons for disc structural failure. The exact relationships between microbial colonization and IVD structural failure are not well understood. This meta-analysis aimed to investigate the impact of microbial colonization and its location (such as skin, IVD, muscle, soft tissues, and blood) on IVD structural failure and corresponding low back pain (LBP) if any. We searched four online databases for potential studies. The potential relationships between microbial colonization in different sample sources (such as skin, IVD, muscle, soft tissues, and blood) and IDD and endplate change were considered as primary outcomes. Odds ratio (OR) and 95% confidence intervals (CI) for direct comparisons were reported. Grading of Recommendations Assessment, Development and Evaluation (GRADE) scale was used to assess the quality of evidence. Twenty-five cohort studies met the selection criteria. Overall pooled prevalence of microbial colonization in 2419 patients with LBP was 33.2% (23.6%-43.6%). The pooled prevalence of microbial colonization in 2901 samples was 29.6% (21.0%-38.9%). Compared with the patients without endplate change, the patients with endplate changes had higher rates of microbial colonization of disc (OR = 2.83; 95% CI = 1.93-4.14; I 2 = 37.6%; p = 0.108). The primary pathogen was Cutibacterium acnes which was present in 22.2% of cases (95% CI = 13.3%-32.5%; I 2 = 96.6%; p = 0.000). This meta-analysis and systematic review found low-quality grade evidence for an association between microbial colonization of disc with endplate changes. The primary pathogen was C. acnes. Due to lack of enough high-quality studies and methodological limitations of this review, further studies are required to improve our understanding of the potential relationships and mechanisms of microbiota, dysbiosis, IVD colonization and IVD structural failure.

Time-course gait pattern analysis in a rat model of foot drop induced by ventral root avulsion injury

Foot drop is a common clinical gait impairment characterized by the inability to raise the foot or toes during walking due to the weakness of the dorsiflexors of the foot. Lumbar spine disorders are common neurogenic causes of foot drop. The accurate prognosis and treatment protocols of foot drop are not well delineated in the scientific literature due to the heterogeneity of the underlying lumbar spine disorders, different severities, and distinct definitions of the disease. For translational purposes, the use of animal disease models could be the best way to investigate the pathogenesis of foot drop and help develop effective therapeutic strategies for foot drops. However, no relevant and reproducible foot drop animal models with a suitable gait analysis method were developed for the observation of foot drop symptoms. Therefore, the present study aimed to develop a ventral root avulsion (VRA)-induced foot drop rat model and record detailed time-course changes of gait pattern following L5, L6, or L5 + L6 VRA surgery. Our results suggested that L5 + L6 VRA rats exhibited changes in gait patterns, as compared to sham lesion rats, including a significant reduction of walking speed, step length, toe spread, and swing phase time, as well as an increased duration of the stance phase time. The ankle kinematic data exhibited that the ankle joint angle increased during the mid-swing stage, indicating a significant foot drop pattern during locomotion. Time-course observations displayed that these gait impairments occurred as early as the first-day post-lesion and gradually recovered 7-14 days post-injury. We conclude that the proposed foot drop rat model with a video-based gait analysis approach can precisely detect the foot drop pattern induced by VRA in rats, which can provide insight into the compensatory changes and recovery in gait patterns and might be useful for serving as a translational platform bridging human and animal studies for developing novel therapeutic strategies for foot drop.

Albumin-to-Alkaline Phosphatase Ratio as a Prognostic Biomarker for Spinal Fusion in Lumbar Degenerative Diseases Patients Undergoing Lumbar Spinal Fusion

Objective: To determine if preoperative albumin-alkaline phosphatase ratio (AAPR) is predictive of clinical outcomes in patients with degenerative lumbar diseases undergoing lumbar fusion. Method: 326 patients undergoing posterior lumbar decompression and fusion were retrospectively analyzed. The cumulative grade was calculated by summing the Pfirrmann grades of all lumbar discs. Grouping was based on the 50th percentile of cumulative grade. The relationship between AAPR, intervertebral disc degeneration (IDD) severity, and fusion rate was explored using correlation analyses and logistic regression models. Meanwhile, the ROC curve evaluated the discrimination ability of AAPR in predicting severe degeneration and non-fusion. Results: High AAPR levels were significantly negatively correlated with severe degeneration and non-fusion rate. A multivariate binary logistic analysis revealed that high preoperative AAPR was an independent predictor of severe degeneration and postoperative non-fusion (OR: 0.114; 95% CI: 0.027−0.482; p = 0.003; OR: 0.003; 95% CI: 0.0003−0.022; p < 0.001). The models showed excellent discrimination and calibration. The areas under the curve (AUC) of severe degeneration and non-fusion identified by AAPR were 0.635 and 0.643. Conclusion: The AAPR can help predict the severity of disc degeneration and the likelihood of non-fusion.

Lorentzian-Corrected Apparent Exchange-Dependent Relaxation (LAREX) Ω-Plot Analysis-An Adaptation for qCEST in a Multi-Pool System: Comprehensive In Silico, In Situ, and In Vivo Studies

Based on in silico, in situ, and in vivo studies, this study aims to develop a new method for the quantitative chemical exchange saturation transfer (qCEST) technique considering multi-pool systems. To this end, we extended the state-of-the-art apparent exchange-dependent relaxation (AREX) method with a Lorentzian correction (LAREX). We then validated this new method with in situ and in vivo experiments on human intervertebral discs (IVDs) using the Kendall-Tau correlation coefficient. In the in silico experiments, we observed significant deviations of the AREX method as a function of the underlying exchange rate (kba) and fractional concentration (fb) compared to the ground truth due to the influence of other exchange pools. In comparison to AREX, the LAREX-based Ω-plot approach yielded a substantial improvement. In the subsequent in situ and in vivo experiments on human IVDs, no correlation to the histological reference standard or Pfirrmann classification could be found for the fb (in situ: τ = −0.17 p = 0.51; in vivo: τ = 0.13 p = 0.30) and kba (in situ: τ = 0.042 p = 0.87; in vivo: τ = −0.26 p = 0.04) of Glycosaminoglycan (GAG) with AREX. In contrast, the influence of interfering pools could be corrected by LAREX, and a moderate to strong correlation was observed for the fractional concentration of GAG for both in situ (τ = −0.71 p = 0.005) and in vivo (τ = −0.49 p < 0.001) experiments. The study presented here is the first to introduce a new qCEST method that enables qCEST imaging in systems with multiple proton pools.

SPECT Imaging of Acute Disc Herniation by Targeting Integrin α5β1 in Rat Models

Objective

Traditional morphological imaging of intervertebral disc herniation (IVDH) is challenging in early disease diagnosis. Aiming at the early diagnosis of IVD by non-invasive molecular imaging targeting of integrin α5β1, we performed novel imaging in rats with acute IVDH for the first time.

Methods

Animal models were prepared by conducting an established needle puncture procedure through the normal intervertebral disc (IVD). The disc-injured rats underwent SPECT/CT imaging of the ^99mTc-3PisoDGR2 peptide at 1 day to 2 months postinjury. The expression change of integrin α5β1 was determined by anti-integrin α5 and anti-integrin α5β1 immunohistochemistry (IHC). Magnetic resonance imaging (MRI) was performed for comparison during disease progression. The morphological changes of the disc were determined by safranin-O staining.

Results

Rats with acute IVDH showed gradually increased disc uptake of ^99mTc-3PisoDGR2 from 1 to 7 days posttreatment, which was a significantly higher level than that of the normal disks in degenerative diseases. IHC results showed the expression of integrin α5β1 on the surface of annulus fibrosus (AF) cells and nucleus pulposus (NP) cells, which agreed with the uptake data. MRI showed a progressively decreased T2 density and MRI index throughout the investigation. Hematoxylin and eosin (HE) staining and safranin-O staining revealed a disorganized structure of the IVD as well as loss of proteoglycans after puncture.

Conclusions

The present study demonstrated a good correlation between integrin α5β1 expression and acute disc herniation. The SPECT/CT imaging of ^99mTc-3PisoDGR2 targeting integrin α5β1 may diagnose IVDH in an acute phase for early disease management.

Lumbosacral Transitional Vertebra Contributed to Lumbar Spine Degeneration: An MR Study of Clinical Patients

We aimed to comprehensively characterize degenerative findings associated with various types of lumbosacral transitional vertebra (LSTV) on magnetic resonance images. Three hundred and fifty patients with LSTV (52.3 ± 10.9 years), including 182 Castellvi type I, 107 type II, 43 type III, and 18 type IV, and 179 controls without LSTV (50.6 ± 13.1 years), were studied. Discs, endplates, and posterior vertebral structures were assessed and compared to those of controls for the most caudal three discs on MRIs. There were no differences in degenerative findings between patients with type I LSTV and controls. For types III and IV, the transitional discs had smaller sizes, lower Pfirrmann scores, and lower rates of disc bulging (2.3% and 5.6% vs. 39.1%), osteophytes (2.3% vs. 15.1%), disc herniation (2.3% and 5.6% vs. 31.8%), and Modic changes (2.3% and 5.6% vs. 16.8%) than controls. However, the cranial discs had more severe Pfirrmann scores, disc narrowing and spinal canal narrowing, and greater rates of disc herniation (41.9% and 50.0% vs. 25.7%), endplate defects (27.9% and 33.3% vs. 14.4%) and spondylolisthesis (18.6% vs. 7.3%) than controls. Type II LSTV was associated with degenerative findings in the cranial segments but to a lesser degree, as compared with type III/IV LSTV. Thus, Castellvi type III/IV LSTV predisposed the adjacent spinal components to degeneration and protected the transitional discs. Type II LSTV had significant effects in promoting transitional and adjacent disc degeneration. Type I LSTV was not related to spinal degeneration.

Distribution Patterns of Degeneration of the Lumbar Spine in a Cohort of 200 Patients with an Indication for Lumbar MRI

Lower back pain is one of the most common causes of a reduced quality of life. Magnetic resonance imaging (MRI) is the best suited imaging technique to detect causes of that pain. We retrospectively evaluated the MRIs of the lumbar spine for 200 patients in order to describe the distribution of signs of degeneration with regard to age, sex, and position of the disc affected. The number of spinal segments affected by degeneration increased with age, as did the number of signs of degeneration per segment. In patients aged between 21 and 30, 38.8% of discs were affected, while for patients aged between 51 and 60, 91.6% of discs were affected. There was no statistically significant gender difference. The lower two segments were most commonly affected by degeneration. The most common were structural changes to the discs, which affected 88.4% of patients over 50. Spondylosis was the most common bone-related change, found in 60.4% of patients over the age of 50. A reduction in disc height increases the likelihood of structural changes to the disc and bone-related changes. When investigating risk factors for developing disc-related diseases, the complex disc degeneration patterns described here should be taken into account.

Lumbar Intervertebral Disc Herniation: Annular Closure Devices and Key Design Requirements

Lumbar disc herniation is one of the most common degenerative spinal conditions resulting in lower back pain and sciatica. Surgical treatment options include microdiscectomy, lumbar fusion, total disc replacement, and other minimally invasive approaches. At present, microdiscectomy procedures are the most used technique; however, the annulus fibrosus is left with a defect that without treatment may contribute to high reherniation rates and changes in the biomechanics of the lumbar spine. This paper aims to review current commercially available products that mechanically close the annulus including the AnchorKnot® suture-passing device and the Barricaid® annular closure device. Previous studies and reviews have focused mainly on a biomimetic biomaterials approach and have described some mechanical and biological requirements for an active annular repair/regeneration strategy but are still far away from clinical implementation. Therefore, in this paper we aim to create a design specification for a mechanical annular closure strategy by identifying the most important mechanical and biological design parameters, including consideration of material selection, preclinical testing requirements, and requirements for clinical implementation.

Trends and patterns of thoracic intervertebral disc degeneration in symptomatic subjects: a magnetic resonance imaging analysis

PURPOSE

This study aimed to analyse the trends and patterns of IVD degeneration in different age groups at each level of the thoracic spine.

METHODS

This cross-sectional MRI study included 1000 symptomatic patients who had undergone upright thoracic spine MRI. A total of 13,000 thoracic IVDs from C7/T1 to T12/L1 were classified into five grades using Pfirrmann classification. Patients were divided according to their ages into five groups (n = 200/group). The severity and pattern of IVD degeneration were analysed in each age group. A predictive model of the severity and pattern of IVD degeneration in each age group was proposed.

RESULTS

The total grade of IVD degeneration and the number of degenerated levels increased with increasing age (P < 0.001). The most common degenerated level was T6/7 (13.3%), while the least common degenerated level was T12/L1 (1.8%). The most common grades were grade I in group 1 (60.5%), grade II in groups 2 (39%) and 3 (37.3%), and grade III in groups 4 (42.5%) and 5 (44.6%). Adjacent-level degenerations were more common than skip-level degenerations. Severe disc degeneration (Pfirrmann grades IV or V) could be predicted to occur more in group 5 (patients with 60 years and above) (margin = 0.79, 95% CI = 0.73-0.84, P < 0.001).

CONCLUSIONS

The severity of thoracic IVD degeneration and the number of degenerated levels increased with age. Disc degeneration was more accelerated in the mid-thoracic spine. Adjacent-level degeneration was more common than skip-level degenerations.

Effects of controlled hypotension with restrictive transfusion on intraoperative blood loss and systemic oxygen metabolism in elderly patients who underwent lumbar fusion

BACKGROUND

The effects of restrictive fluid therapy combined with controlled hypotension in the elderly on systemic oxygen metabolism and renal function are clinical concerns. The aim of this study was to evaluate blood loss, oxygen metabolism, and renal function in different levels of controlled hypotension induced by intravenous nitroglycerin, in combination with limited infusion, in elderly patients undergoing posterior lumbar fusion.

METHODS

A total of 40 patients, aged 60-75 with ASA grade II or III, who were planned for posterior lumbar fusion were randomly allocated into two groups: experimental group [target mean arterial pressure 65 mmHg (MAP 65) or control group (MAP 75)]. Indicators for blood loss, hemodynamic, systemic oxygen metabolism, and renal function evaluation index were recorded before operation (T0), 1 h after induced hypotension (T1), 2 h after hypotension (T2), and in recovery (T3). We compared changes in these parameters between groups to evaluate the combined effects of controlled hypotension with restrictive infusion.

RESULTS

CI, DO₂I, and VO₂I were lower in both groups at T1-T3 compared with T0 (p < 0.05). DO₂I and VO₂I in the MAP 65 group were lower than the MAP 75 group after operation. In both groups, SCysC increased at T1, T2, and T3 (p < 0.05) compared with T0.

CONCLUSIONS

Restrictive transfusion and control MAP at 65 mmHg can slightly change in renal function and reduce the risk of insufficient oxygen supply and importantly have no significant effect on blood loss and postoperative complications.

TRIAL REGISTRATION

ChiCTR-INR-16008153 . Registered on 25 March 2016.

Intervertebral Disc Diseases PART 2: A Review of the Current Diagnostic and Treatment Strategies for Intervertebral Disc Disease

With an aging population, there is a proportional increase in the prevalence of intervertebral disc diseases. Intervertebral disc diseases are the leading cause of lower back pain and disability. With a high prevalence of asymptomatic intervertebral disc diseases, there is a need for accurate diagnosis, which is key to management. A thorough understanding of the pathophysiology and clinical manifestation aids in understanding the natural history of these conditions. Recent developments in radiological and biomarker investigations have potential to provide noninvasive alternatives to the gold standard, invasive discogram. There is a large volume of literature on the management of intervertebral disc diseases, which we categorized into five headings: (a) Relief of pain by conservative management, (b) restorative treatment by molecular therapy, (c) reconstructive treatment by percutaneous intervertebral disc techniques, (d) relieving compression and replacement surgery, and (e) rigid fusion surgery. This review article aims to provide an overview on various current diagnostic and treatment options and discuss the interplay between each arms of these scientific and treatment advancements, hence providing an outlook of their potential future developments and collaborations in the management of intervertebral disc diseases.

The prevalence of lumbar disc degeneration in symptomatic younger patients: A study of MRI scans

STUDY DESIGN

Retrospective Cohort Study.

OBJECTIVE

Low back pain (LBP) and radiculopathy present a significant burden to patients and healthcare systems. Lumbar disc degeneration (LDD) is associated with LBP. While the prevalence of LDD in older, symptomatic, patients has been extensively documented there has been little describing the prevalence in younger patients.

METHODS

1011 patients aged 20-30 years, who had undergone Magnetic Resonance Imaging (MRI), for investigation of LBP and or radiculopathy, over a 9-year period were identified. Those who had previous surgery, congenital deformities or unavailable imaging were excluded. A single surgeon evaluated the MRI images of 730 patients and classified each lumbar disc according to the Pfirrmann classification. 105 randomly selected patient's imaging was reviewed again by the primary reviewer and by a consultant musculoskeletal radiologist with the kappa coefficients for inter-rater and intra-rater agreement calculated.

RESULTS

Of the 730 patients, 428 (58.6%) had MRI evidence of LDD (Pfirrmann III, IV, V). 255 (59.6%) demonstrated single level pathology and 173 (41.4%) multilevel involvement. There was very high intra/inter observer agreement with kappa coefficients for intra-observer agreement from 0.65 to 0.98 and inter-observer agreement from 0.51 to 0.88.

CONCLUSIONS

This is the largest study to document the prevalence of LDD in a symptomatic young cohort. A large prospective study including non-symptomatic patients and information on associated factors would add further information. Given the considerably higher than anticipated prevalence identified in this study and the significant burden associated with LBP this study should encourage such further research.

Functional Changes in Patients and Morphological Changes in the Lumbar Intervertebral Disc after Applying Lordotic Curve-Controlled Traction: A Double-Blind Randomized Controlled Study

Background and Objectives: Lumbar traction is widely used as a non-operative treatment for lumbar intervertebral disc disease. The effect of traditional traction (TT) using linear-type traction devices remains controversial for various reasons, including technical limitations. Thus, the purpose of this study was to compare the effects of the newly developed lumbar lordotic curve-controlled traction (L-LCCT) and TT on functional changes in patients and morphological changes in the vertebral disc. Materials and Methods: A total of 40 patients with lumbar intervertebral disc disease at the L4/5 or L5/S1 level as confirmed by magnetic resonance imaging were recruited and divided into two groups (L-LCCT or TT). The comprehensive health status changes of the patients were recorded using pain and functional scores (the visual analogue scale, the Oswestry Disability Index, and the Roland–Morris Disability Questionnaire) and morphological changes (in the lumbar central canal area) before and after traction treatment. Results: Pain scores were significantly decreased after traction in both groups (p < 0.05). However, functional scores and morphological changes improved significantly after treatment in the L-LCCT group only (p < 0.05). Conclusions: We suggest that L-LCCT is a viable option for resolving the technical limitations of TT by maintaining the lumbar lordotic curve in patients with lumbar intervertebral disc disease.

Bony stress in the lumbar spine is associated with intervertebral disc degeneration and low back pain: a retrospective case-control MRI study of patients under 25 years of age

PURPOSE

Abnormal stress in the lumbar vertebra, also known as bony stress, can be a precursor to degenerative changes which may manifest as low back pain (LBP). However, the prevalence of bony stress in the lumbar spine and its relationship with degenerative changes and LBP is unclear. The purpose of this study was to evaluate the prevalence of bony stress in the lumbar spine and its relationship with intervertebral disc (IVD) degeneration, facet osteoarthritis and LBP in patients under 25 years of age.

METHODS

A retrospective case-control study of 130 patients under 25 years of age was conducted from a population of 493 patients who had lumbar MRI across three imaging centres over three years. A cohort of 55 consecutive patients with bony stress was identified. A control group of consecutive patients (n = 75) without bony stress was also selected from the population.

RESULTS

Bony stress was prevalent in 11% (95% CI [8.4-14.5%]) of patients and was not diagnosed in 36% (95% CI [22-55%]) of these cases. Patients with bony stress had over twofold (OR 2.3, 95% CI [1.1-4.8]) and fivefold (OR 5.3, 95% CI [2.11-13.3]) higher likelihood of having IVD degeneration and LBP, respectively, when compared with the control group. Bony stress was not found to be associated with facet osteoarthritis.

CONCLUSION

Bony stress in the lumbar spine was prevalent in 11% of patients under 25 years of age. It was commonly undiagnosed in radiology reports (not reported in 36% of the cases). Being significantly associated and with an increased likelihood of IVD degeneration and LBP, we posit that bony stress is likely a symptomatic and clinically meaningful diagnostic entity in the assessment of LBP. These slides can be retrieved under Electronic Supplementary Material.

Multiplex Epigenome Editing of Dorsal Root Ganglion Neuron Receptors Abolishes Redundant Interleukin 6, Tumor Necrosis Factor Alpha, and Interleukin 1β Signaling by the Degenerative Intervertebral Disc

Back pain is the leading cause of disability worldwide and contributes to significant socioeconomic impacts. It has been hypothesized that the degenerative intervertebral disc (IVD) contributes to back pain by sensitizing nociceptive neurons innervating the IVD to stimuli that would not be painful to healthy patients. However, the inflammatory signaling networks mediating this sensitization remain poorly understood. A better understanding of the underlying mechanisms of degenerative IVD-induced changes in nociception is required to improve the understanding and treatment of back pain. Toward these ends, a novel in vitro model was developed to investigate degenerative IVD-induced changes in dorsal root ganglion (DRG) neuron activation by measuring DRG neuron activity following neuron seeding on human degenerative IVD tissue collected from patients undergoing surgical treatment for back pain. Lentiviral clustered regularly interspaced palindromic repeat (CRISPR) epigenome editing vectors were built to downregulate the inflammatory receptors TNFR1, IL1R1, and IL6st in DRG neurons in single- and multiplex. Multiplex CRISPR epigenome editing of inflammatory receptors demonstrated that degenerative IVD tissue drives thermal sensitization through the simultaneous and redundant signaling of interleukin (IL)-6, tumor necrosis factor alpha (TNF-α), and IL-1β. This work elucidates redundant signaling pathways in neuron interactions with the degenerative IVD and suggests the need for multiplex targeting of IL-6, TNF-α, and IL-1β for pain modulation in the degenerative IVD.

Differences in Trabecular Bone, Cortical Shell, and Endplate Microstructure Across the Lumbar Spine

Background

The quality of the vertebral body structures such as endplate, cortex, and trabecular bone is important for understanding the performance of implants, particularly at the bone-implant interface. Although vertebral body structures have been analyzed separately in the literature, there is no comprehensive study to assess these anatomical measurements along with their interrelationships in the lumbar spine. Therefore, the purpose of this study was to assess variations in trabecular microstructure, vertebral endplate thickness and concavity, and vertebral body cortex thickness within the lumbar spine.

Methods

A total of 80 lumbar vertebrae (L1-L5) were dissected from 16 human cadaver specimens and imaged with microcomputed tomography to determine trabecular microstructure, vertebral cortex thickness, endplate thickness, and maximum endplate concavity depth. A paired t test and regression analysis were used to determine significant differences (P < .05) between different vertebral levels and correlations between the analyzed anatomical parameters.

Results

L1 vertebra had significantly better (P < .02) trabecular bone microstructure (eg, trabecular bone volume fraction) than all other lumbar vertebrae. However, L1 vertebra also had significantly thinner (P ≤ .02) anterior, left, and right cortices compared to all other vertebral levels. Within L3-L5 intervertebral disc spaces, cranial endplates had significantly greater (P ≤ .03) thickness and maximum concavity depth compared to their respective caudal endplates. No strong correlations were observed between trabecular bone microstructure, maximum endplate concavity depth, vertebral cortex, and endplate thickness parameters.

Conclusions

Detailed reference data of these anatomical parameters for each lumbar vertebral body can aid in improved understanding of bone quality, particularly when assessing different implant designs and fixation approaches. Moreover, such anatomical knowledge may help clinicians with optimal implant design selection and surgical placement of these devices into their respective locations.

Magnetic resonance imaging analysis of work-related chronic low back pain: comparisons of different lumbar disc patterns

Background

Currently, there is a lack of comparative research about different lumbar disc patterns in patients with work-related chronic low back pain (CLBP) based on magnetic resonance imaging (MRI) analysis. Therefore, this study, on different patterns of lumbar disc degeneration or herniation in patients with CLBP, is valuable. In this study, we retrospectively investigated lumbar degenerative changes in patients with CLBP by using MRI analysis.

Materials and methods

Two hundred and eighty-three patients (110 women and 173 men) with work-related CLBP were enrolled and divided into four groups based on intervertebral disc morphology from MRI analysis, including normal discs (ND) group, degenerative discs (DD) group, bulging discs (BD) group, and herniated discs (HD) group. Demographic characteristics, occupational information, Visual Analog Scale (VAS) scores, and Oswestry Disability Index (ODI) scores were analyzed. Moreover, multiple parameters were investigated in the MRI analysis.

Results

The mean age of all 283 patients was 41.8±12.0 years (range, 18-80) and the mean duration of CLBP for all patients was 24.5±24.9 months. There were no significant differences in the patients' BMI, history of smoking, and education level (P>0.05). The three most common occupational types were manual worker, desk worker, and technician. The VAS and ODI scores of patients with CLBP in the DD, BD, and HD groups were significantly higher than those of patients in the ND group (P<0.05). The degrees of degeneration of L4/5 and L5/S1 were significantly higher than those of other intervertebral discs (P<0.05). The disc heights of L4/5 in the BD and HD groups were significantly lower than those of the ND group (P<0.05) and the disc height of L5/S1 in the HD group was significantly lower than that of the ND group (P<0.05). At the neutral position, the distances of L3/4, L4/5, and L5/S1 discs' bulge/herniation in the BD and HD groups were significantly higher than those in the ND and DD groups (P<0.05).

Conclusion

In summary, more severe degenerative changes of lower lumbar discs (L4/5 and L5/S1) such as higher degree of degeneration of disc, lower disc height, and significant displacement of disc were found in patients with work-related CLBP based on MRI analysis.

Associations between back pain across adulthood and spine shape in early old age in a British birth cohort

We aimed to examine whether back pain across adulthood was associated with spine shape at age 60–64 years. Data were from 1405 participants in the MRC National Survey of Health and Development, a nationally representative British birth cohort. Back pain was ascertained during nurse interviews at ages 36, 43, 53 and 60–64 years. Cumulative exposure to back pain was then derived by counting the number of ages at which back pain was reported. Statistical shape modelling was used to characterise thoracolumbar spine shape using lateral dual-energy x-ray absorptiometry images which were ascertained at age 60–64 years. Linear regression models were used to test associations of spine shape modes (SM) with: (1) cumulative exposure to back pain; (2) back pain reports during different periods of adulthood. After adjusting for sex, higher cumulative exposure to back pain across adulthood was associated with wedge-shaped L4-5 disc (lower SM4 scores) and smaller disc spaces (higher SM8 scores) in both sexes. In addition, reporting of back pain at ages 53 and/or 60–64 years was associated with smaller L4-5 disc space (lower SM6 scores) in men but not women. These findings suggest that back pain across adulthood may be associated with specific variations in spine shapes in early old age.

Diagnostic accuracy of diagnostic imaging for lumbar disc herniation in adults with low back pain or sciatica is unknown; a systematic review

Main text

We aim to summarize the available evidence on the diagnostic accuracy of imaging (index test) compared to surgery (reference test) for identifying lumbar disc herniation (LDH) in adult patients.For this systematic review we searched MEDLINE, EMBASE and CINAHL (June 2017) for studies that assessed the diagnostic accuracy of imaging for LDH in adult patients with low back pain and surgery as the reference standard. Two review authors independently selected studies, extracted data and assessed risk of bias. We calculated summary estimates of sensitivity and specificity using bivariate analysis, generated linked ROC plots in case of direct comparison of diagnostic imaging tests and assessed the quality of evidence using the GRADE-approach.We found 14 studies, all but one done before 1995, including 940 patients. Nine studies investigated Computed Tomography (CT), eight myelography and six Magnetic Resonance Imaging (MRI). The prior probability of LDH varied from 48.6 to 98.7%. The summary estimates for MRI and myelography were comparable with CT (sensitivity: 81.3% (95%CI 72.3-87.7%) and specificity: 77.1% (95%CI 61.9-87.5%)). The quality of evidence was moderate to very low.

Conclusions

The diagnostic accuracy of CT, myelography and MRI of today is unknown, as we found no studies evaluating today's more advanced imaging techniques. Concerning the older techniques we found moderate diagnostic accuracy for all CT, myelography and MRI, indicating a large proportion of false positives and negatives.

Diagnosis and Incidence of Spondylosis and Cervical Disc Disorders in the University Clinical Hospital in Olsztyn, in Years 2011-2015

BACKGROUND

Disorders connected with the musculoskeletal and central nervous system dysfunction are the most significant clinical problem worldwide. Our earlier research has shown that back and spinal disorders and lumbar disc disorders were most frequently diagnosed using MRI scanner at the University Clinical Hospital (UCH) in Olsztyn in years 2011-2015. We have also observed that another two diseases of spinal column, spondylosis and cervical disc disorders, were also very prevalent. The main objective of this work was to analyze the prevalence of spondylosis and cervical disc disorders in the study population diagnosed at UCH in years 2011-2015.

METHODS

The digital database including patients' diagnostic and demographic information was generated based on MRI reports from years 2011-2015 and analyzed using SPSS software.

RESULTS

Within the study group (n = 13298) the most frequently MRI-diagnosed diseases were musculoskeletal group (M00-M99; n = 7711; 57,98%) and cervical disc disorders (M50; n = 1659; 12,47%) and spondylosis (M47, n = 611; 4,59%). More women (67%) than men (33%) were enrolled in the study, and the largest fraction of the study population was in the range of 51-60 years, with about 1/3 of cases of both diseases diagnosed in early age range of 31-40 years.

CONCLUSION

Significant number of patients presenting with either of the spine disorders at the young age of 31-40 years points to the necessity of introducing methods preventing disorders of the vertebral column at younger age, preferably at school age.

Hypoxia-inducible factor (HIF)-1alpha knockout accelerates intervertebral disc degeneration in mice

INTRODUCTION

The abnormality of nucleus pulposus (NP) plays a critical role in intervertebral disc (IVD) degeneration, in which NP cells show apoptosis and fibrosis, leading to the ability of the disc to transfer and distribute loads between the vertebrae is decreased. Considering that hypoxia inducible factor-1α (HIF-1α) is abundantly expressed in NP and that it mediates cell proliferation, migration and apoptosis in various cell types, we hypothesized that NP-HIF-1α plays an important role in NP and evaluate whether NP-HIF-1α is involved in IVD degeneration.

MATERIAL AND METHODS

Sonic Hedgehog-Cre^+/- mice were crossed with HIF-1α^flox/flox mice to generate NP specific HIF-1α-deficient (HIF-1α^-/-) mice. Magnetic resonance imaging (MRI) study was used to evaluate NP dehydration and X-ray study was used to acquire the changes of disc height. Histological changese, content of glycoproteins and the in situ expression of aggrecan were evaluated by hematoxylin & eosin (H&E) staining, safranin-O/fast green staining and immunohistochemistry assay, respectively. Western bloting was used to detect the change of extracellular matrix in IVD.

RESULTS

Firstly, the results of in situ hybridization confirmed that HIF-1α in NP was successfully knocked out in HIF-1α^-/- mice. Next, for HIF-1α deficiency mice, imaging study shows IVD was narrowed in X-ray and signal intensity of NP was decreased in MR T2-weight imaging. Accordingly, the size and cell number of NP and proteoglycan content was decreased in NP-HIF-1α^-/- mice. Finally, Western bloting shows that protein level of collagen II and aggrecan, two main matrix in disc, were both decreased in NP-HIF-1α^-/- mice.

CONCLUSIONS

The present study demonstrates that HIF-1α is essential for NP development and homeostasis and the deficiency of NP-HIF-1α leads to IVD degeneration in mice.

CRISPR Epigenome Editing of AKAP150 in DRG Neurons Abolishes Degenerative IVD-Induced Neuronal Activation

Back pain is a major contributor to disability and has significant socioeconomic impacts worldwide. The degenerative intervertebral disc (IVD) has been hypothesized to contribute to back pain, but a better understanding of the interactions between the degenerative IVD and nociceptive neurons innervating the disc and treatment strategies that directly target these interactions is needed to improve our understanding and treatment of back pain. We investigated degenerative IVD-induced changes to dorsal root ganglion (DRG) neuron activity and utilized CRISPR epigenome editing as a neuromodulation strategy. By exposing DRG neurons to degenerative IVD-conditioned media under both normal and pathological IVD pH levels, we demonstrate that degenerative IVDs trigger interleukin (IL)-6-induced increases in neuron activity to thermal stimuli, which is directly mediated by AKAP and enhanced by acidic pH. Utilizing this novel information on AKAP-mediated increases in nociceptive neuron activity, we developed lentiviral CRISPR epigenome editing vectors that modulate endogenous expression of AKAP150 by targeted promoter histone methylation. When delivered to DRG neurons, these epigenome-modifying vectors abolished degenerative IVD-induced DRG-elevated neuron activity while preserving non-pathologic neuron activity. This work elucidates the potential for CRISPR epigenome editing as a targeted gene-based pain neuromodulation strategy.

The comparison of measurement between ultrasound and computed tomography for abnormal degenerative facet joints: A STROBE-compliant article

Besides the study on examining facet joints of lumbar spine by ultrasound in normal population, there has not been any related report about examining normal facet joints of lumbar spine by ultrasound so far. This study was aimed to explore the feasibility of ultrasound assessment of lumber spine facet joints by comparing ultrasound measure values of normal and degenerative lumber spine facet joints, and by comparing measure values of ultrasound and computed tomography (CT) of degenerative lumber spine facet joints.This study included 15 patients who had chronic low back pain because of degenerative change in lumbar vertebrae, and 19 volunteers who did not have low back pain or pain in the lower limb. The ultrasound measure values (height [H] and width [W]) of normal and degenerative lumber spine facet joints were compared. And the differentiation between measure values (H and W) of ultrasound and CT of degenerative lumber spine facet joints was also analyzed.The ultrasound clearly showed abnormal facet joints lesion, which was characterized by hyperostosis on the edge of joints, bone destruction under joints, and thinner or thicker articular cartilage. There were significant differences between the ultrasound measure values of the normal (H: 1.26 ± 0.03 cm, W: 0.18 ± 0.01 cm) and abnormal facet joints (H: 1.43 ± 0.05 cm, W: 0.15 ± 0.02 cm) (all P < .05). However, there were no significant differences between the measure values of the ultrasound (H: 1.43 ± 0.17 cm, W: 0.15 ± 0.03 cm) and CT (H: 1.42 ± 0.16, W: 0.14 ± 0.03) of the degenerative lumber spine facet joints (all P > .05).Ultrasound can clearly show the structure of facet joints of lumbar spine. It is precise and feasible to assess facet joints of lumbar spine by ultrasound. This study has important significance for the diagnosis of lumbar facet joint degeneration.