Low back pain

An anti-senescence hydrogel with pH-responsive drug release for mitigating intervertebral disc degeneration and low back pain

Oxidative stress and aging lead to progressive senescence of nucleus pulposus (NP) cells, resulting in intervertebral disc (IVD) degeneration (IVDD). In some cases, degenerative IVD can further cause low back pain (LBP). Several studies have confirmed that delaying and rejuvenating the senescence of NP cells can attenuate IVDD. However, the relatively closed tissue structure of IVDs presents challenges for the local application of anti-senescence drugs. Here, we prepared an anti-senescence hydrogel by conjugating phenylboronic acid-modified gelatin methacryloyl (GP) with quercetin to alleviate IVDD by removing senescent NP cells. The hydrogel exhibited injectability, biodegradability, prominent biocompatibility and responsive release of quercetin under pathological conditions. In vitro experiments demonstrated that the hydrogel could reduce the expression of senescence markers and restore the metabolic balance in senescent NP cells. In vivo studies validated that a single injection of the hydrogel in situ could maintain IVD tissue structure and alleviate sensitivity to noxious mechanical force in the rat models, indicating a potential therapeutic approach for ameliorating IVDD and LBP. This approach helps prevent potential systemic toxicity associated with systemic administration and reduces the morbidity resulting from repeated injections of free drugs into the IVD, providing a new strategy for IVDD treatment.

A multifunctional scaffold that promotes the scaffold-tissue interface integration and rescues the ROS microenvironment for repair of annulus fibrosus defects

Due to the limited self-repair ability of the annulus fibrosus (AF), current tissue engineering strategies tend to use structurally biomimetic scaffolds for AF defect repair. However, the poor integration between implanted scaffolds and tissue severely affects their therapeutic effects. To solve this issue, we prepared a multifunctional scaffold containing loaded lysyl oxidase (LOX) plasmid DNA exosomes and manganese dioxide nanoparticles (MnO2 NPs). LOX facilitates extracellular matrix (ECM) cross-linking, while MnO2 NPs inhibit excessive reactive oxygen species (ROS)-induced ECM degradation at the injury site, enhancing the crosslinking effect of LOX. Our results revealed that this multifunctional scaffold significantly facilitated the integration between the scaffold and AF tissue. Cells were able to migrate into the scaffold, indicating that the scaffold was not encapsulated as a foreign body by fibrous tissue. The functional scaffold was closely integrated with the tissue, effectively enhancing the mechanical properties, and preventing vascular invasion, which emphasized the importance of scaffold-tissue integration in AF repair.

Spotlight on necroptosis: Role in pathogenesis and therapeutic potential of intervertebral disc degeneration

Intervertebral disc degeneration (IDD) is the leading cause of low back pain, which is one of the major factors leading to disability and severe economic burden. Necroptosis is an important form of programmed cell death (PCD), a highly regulated caspase-independent type of cell death that is regulated by receptor-interacting protein kinase 1 (RIPK1), RIPK3 and mixed lineage kinase domain-like protein (MLKL)-mediated, play a key role in the pathophysiology of various inflammatory, infectious and degenerative diseases. Recent studies have shown that necroptosis plays an important role in the occurrence and development of IDD. In this review, we provide an overview of the initiation and execution of necroptosis and explore in depth its potential mechanisms of action in IDD. The analysis focuses on the connection between NP cell necroptosis and mitochondrial dysfunction-oxidative stress pathway, inflammation, endoplasmic reticulum stress, apoptosis, and autophagy. Finally, we evaluated the possibility of treating IDD by inhibiting necroptosis, and believed that targeting necroptosis may be a new strategy to alleviate the symptoms of IDD.

Surgical treatment of refractory low back pain using implanted BurstDR spinal cord stimulation (SCS) in a cohort of patients without options for corrective surgery: Findings and results from the DISTINCT study, a prospective randomized multi-center-controlled trial

Background

Low back pain (LBP) is a highly prevalent, disabling condition affecting millions of people. Patients with an identifiable anatomic pain generator and resulting neuropathic lower extremity symptoms often undergo spine surgery, but many patients lack identifiable and/or surgically corrective pathology. Nonoperative treatment options often fail to provide sustained relief. Spinal cord stimulation (SCS) is sometimes used to treat these patients, but the lack of level 1 evidence limits its widespread use and insurance coverage. The DISTINCT RCT study evaluates the efficacy of passive recharge burst SCS compared to conventional medical treatment (CMM) in alleviating chronic, refractory axial low back pain.

Methods

This prospective, multicenter, randomized, study with an optional 6-month crossover involved patients who were not candidates for lumbar spine surgery. The primary and secondary endpoints evaluated improvements in low back pain intensity (NRS), back pain-related disability (ODI), pain catastrophizing (PCS), and healthcare utilization. Patients were randomized to SCS therapy or CMM at 30 US study sites.

Results

The SCS arm reported an 85.3% NRS responder rate (≥ 50% reduction) compared to 6.2% (5/81) in the CMM arm. After the 6M primary endpoint, SCS patients elected to remain on assigned therapy and 66.2% (49/74) of CMM patients chose to trial SCS (crossover). At the 12M follow-up, SCS and crossover patients reported 78.6% and 71.4% NRS responder rates. Secondary outcomes indicated significant improvements in ODI, PCS, and reduced healthcare utilization. Six serious adverse events were reported and resolved without sequelae.

Conclusion

DISTINCT chronic low back pain patients with no indication for corrective surgery experienced a significant and sustained response to burst SCS therapy for up to 12 months. CMM patients who crossed over to the SCS arm reported profound improvements after 6 months. This data advocates for a timely consideration of SCS therapy in patients unresponsive to conservative therapy.

Multiomics analysis reveals the potential of LPCAT1-PC axis as a therapeutic target for human intervertebral disc degeneration

Intervertebral disc degeneration (IDD) is a highly prevalent musculoskeletal disorder that is associated with considerable morbidity. However, there is currently no drug available that has a definitive therapeutic effect on IDD. In this study, we aimed to identify the molecular features and potential therapeutic targets of IDD through a comprehensive multiomics profiling approach. By integrating transcriptomics, proteomics, and ultrastructural analyses, we discovered dysfunctions in various organelles, including mitochondria, the endoplasmic reticulum, the Golgi apparatus, and lysosomes. Metabolomics analysis revealed a reduction in total phosphatidylcholine (PC) content in IDD. Through integration of multiple omics techniques with disease phenotypes, a pivotal pathway regulated by the lysophosphatidylcholine acyltransferase 1 (LPCAT1)-PC axis was identified. LPCAT1 exhibited low expression levels and exhibited a positive correlation with PC content in IDD. Suppression of LPCAT1 resulted in inhibition of PC synthesis in nucleus pulposus cells, leading to a notable increase in nucleus pulposus cell senescence and damage to cellular organelles. Consequently, PC exhibits potential as a therapeutic agent, as it facilitates the repair of the biomembrane system and alleviates senescence in nucleus pulposus cells via reversal of downregulation of the LPCAT1-PC axis.

Specific back pain - effective diagnosis and treatment from the radiologist's point of view

The diagnosis and treatment of specific back pain is important in radiology. Due to the high number of patients suffering from back pain, it is important to provide excellent diagnostic and therapeutic support.Based on a recent literature search and considering the relevant guidelines as well as expert opinions, the aspects of specific back pain important for radiologists in terms of pathogenesis, diagnosis, and treatment are presented.Clinical examination in combination with the medical history provides a valid suspected diagnosis. This should subsequently be verified radiologically. MRI is the most effective cross-sectional diagnostic method for investigating specific back pain. A conventional X-ray on two planes in a standing position can be a useful addition if postural causes are suspected. If the clinical symptoms match the morphological findings, radiological treatment can be carried out for nerve root involvement as well as for inflammatory changes of the facet joints. The improvement in symptoms after radiological therapy is considered good overall; at least a short-term improvement in symptoms can generally be achieved, but no reliable data is available regarding the long-term outcome. Using preparations containing triamcinolone, low dosages should be selected in accordance with the guidelines. Embedding in a multimodal pain therapy treatment concept should be considered.Radiology provides essential diagnostic findings regarding specific back pain. Interventional pain therapy is an effective and safe method of treating proven specific back pain. · First examine clinically, then confirm the suspected diagnosis radiologically.. · MRI is usually the method of choice.. · Interventional pain therapy should show success after a maximum of 2 interventions.. · The anti-inflammatory drug dose should be kept as low as possible.. · The individual course determines the number of interventions.. · Stueckle CA, Haage P. Specific back pain - effective diagnosis and treatment from the radiologist's point of view. Fortschr Röntgenstr 2024; DOI 10.1055/a-2371-1752.

Deep learning assisted segmentation of the lumbar intervertebral disc: a systematic review and meta-analysis

BACKGROUND

In recent years, deep learning (DL) technology has been increasingly used for the diagnosis and treatment of lumbar intervertebral disc (IVD) degeneration. This study aims to evaluate the performance of DL technology for IVD segmentation in magnetic resonance (MR) images and explore improvement strategies.

METHODS

We developed a PRISMA systematic review protocol and systematically reviewed studies that used DL algorithm frameworks to perform IVD segmentation based on MR images published up to April 10, 2024. The Quality Assessment of Diagnostic Accuracy Studies-2 tool was used to assess methodological quality, and the pooled dice similarity coefficient (DSC) score and Intersection over Union (IoU) were calculated to evaluate segmentation performance.

RESULTS

45 studies were included in this systematic review, of which 16 provided complete segmentation performance data and were included in the quantitative meta-analysis. The results indicated that DL models showed satisfactory IVD segmentation performance, with a pooled DSC of 0.900 (95% confidence interval [CI]: 0.887-0.914) and IoU of 0.863 (95% CI: 0.730-0.995). However, the subgroup analysis did not show significant effects of factors on IVD segmentation performance, including network dimensionality, algorithm type, publication year, number of patients, scanning direction, data augmentation, and cross-validation.

CONCLUSIONS

This study highlights the potential of DL technology in IVD segmentation and its further applications. However, due to the heterogeneity in algorithm frameworks and result reporting of the included studies, the conclusions should be interpreted with caution. Future research should focus on training generalized models on large-scale datasets to enhance their clinical application.

Screening of NSAIDs library identifies Tinoridine as a novel ferroptosis inhibitor for potential intervertebral disc degeneration therapy

Low back pain (LBP) may profoundly impact the quality of life across the globe, and intervertebral disc degeneration (IVDD) is the major cause of LBP; however, targeted pharmaceutical interventions for IVDD are still lacking. Ferroptosis is a novel form of iron-dependent programmed cell death. Studies have showed that ferroptosis may closely associate with IVDD; thus, targeting ferroptosis may have great potential for IVDD therapy. Non-steroidal anti-inflammatory drugs (NSAIDs) are the first-line medications for LBP, while nuclear factor-erythroid 2-related factor-2 (Nrf2) is a key inhibitory protein for ferroptosis. In the current study, we conducted a molecular docking screening between NSAIDs library and Nrf2 protein. Tinoridine was shown to have a high binding affinity to Nrf2. The in vitro study in nucleus pulposus (NP) cells showed that Tinoridine may promote the expression and activity of Nrf2, it may also rescue RSL3-induced ferroptosis in NP cells. Knockdown of Nrf2 reverses the protective effect of Tinoridine on RSL3-induced ferroptosis in NP cells, suggesting that the inhibitory effect of Tinoridine on ferroptosis is through Nrf2. In vivo study demonstrated that Tinoridine may attenuate the progression of IVDD in rats. As NSAIDs are already clinically used for LBP therapy, the current study supports Tinoridine's application from the view of ferroptosis inhibition.

Single-cell RNA sequencing reveals the CRTAC1+ population actively contributes to the pathogenesis of spinal ligament degeneration by SPP1+ macrophage

Degenerative spinal stenosis is a chronic disease that affects the spinal ligaments and associated bones, resulting in back pain and disorders of the limbs among the elderly population. There are few preventive strategies for such ligament degeneration. We here aimed to establish a comprehensive transcriptomic atlas of ligament tissues to identify high-priority targets for pharmaceutical treatment of ligament degeneration. Here, single-cell RNA sequencing was performed on six degenerative ligaments and three traumatic ligaments to understand tissue heterogeneity. After stringent quality control, high-quality data were obtained from 32,014 cells. Distinct cell clusters comprising stromal and immune cells were identified in ligament tissues. Among them, we noted that collagen degradation associated with CTHRC1+ fibroblast-like cells and calcification linked to CRTAC1+ chondrocyte-like cells were key features of ligament degeneration. SCENIC analysis and further experiments identified ATF3 as a key transcription factor regulating the pathogenesis of CRTAC1+ chondrocyte-like cells. Typically, immune cells infiltrate localized organs, causing tissue damage. In our study, myeloid cells were found to be inflammatory-activated, and SPP1+ macrophages were notably enriched in degenerative ligaments. Further exploration via CellChat analysis demonstrated a robust interaction between SPP1+ macrophages and CRTAC1+ chondrocyte-like cells. Activated by SPP1, ATF3 propels the CRTAC1/MGP/CLU axis, fostering ligament calcification. Our unique resource provides novel insights into possible mechanisms underlying ligament degeneration, the target cell types, and molecules that are expected to mitigate degenerative spinal ligament. We also highlight the role of immune regulation in ligament degeneration and calcification, enhancing our understanding of this disease.

Global years lived with disability for musculoskeletal disorders in adults 70 Years and older from 1990 to 2019, and projections to 2040

In this article, we provided a comprehensive overview and in-depth analysis of global patterns and temporal trends in years lived with disability (YLDs) for musculoskeletal (MSK) disorders in individuals aged ≥70. Data on YLDs for MSK disorders in individuals aged ≥70 were obtained from the Global Burden of Disease 2019. The average annual percentage change (AAPC) was calculated to assess the temporal trends in the YLDs rate of MSK disorders. A Bayesian Age-Period-Cohort model was used to predict the YLDs rate up to the year 2040. In 2019, the global rate of YLDs for MSK disorders in individuals aged ≥70 were 4819.81 (95 % UI: 3402.91 - 6550.77) per 100,000 persons. The YLDs rate of MSK disorders in female was 1.36 times higher than that in male, and was highest in high SDI regions. From 1990 to 2019, the global YLDs rate showed a slightly downward trend (AAPC = -0.04 %, 95 % CI: -0.06 % to -0.03 %), while it significantly increased in high, low-middle, low SDI regions. Tobacco and high body mass index were the primary risk factors worldwide, while in low SDI regions, occupational risks emerged as the predominant factors. Up to 2040, the global YLDs rate of MSK disorders are expected to increase by 1.78 %, with 36.39 %, 20.66 %, 18.96 % and 5.32 % growth in other MSK disorders, rheumatoid arthritis, neck pain and osteoarthritis. MSK disorders are a significant and continuously growing public health concern among older adults. Tailored interventions should be developed for older adults, taking into account the variations across distributions, trends, and risk factors in terms of sex and SDI levels.

Zhiqiao Gancao decoction regulated JAK2/STAT3/ macrophage M1 polarization to ameliorate intervertebral disc degeneration

Background

Zhiqiao Gancao decoction (ZQGCD) was created by Professor Gong Zhengfeng, a renowned Chinese medicine expert. Clinical studies have shown its efficacy in alleviating pain and enhancing lumbar function in intervertebral disc degeneration (IDD) patients. However, the precise mechanism of ZQGCD in treating IDD remains unclear.

Methods

The active components of ZQGCD were identified using Liquid chromatography-tandem mass spectrometry (LC-MS/MS). A rat model of intervertebral disc degeneration was established, and rats in each group received ZQGCD for three weeks. Assessment parameters included hyperalgesia status, observation of intervertebral disc tissue degeneration and macrophage infiltration, and analysis of JAK2/STAT3 pathway protein expression in the intervertebral disc. Primary macrophage M1 polarization was induced using LPS, with cells treated using the JAK2 inhibitor (AZD1480) and ZQGCD to evaluate macrophage polarization, cellular supernatant inflammatory factors, and JAK2/STAT3 pathway expression. Macrophage supernatant served as a conditioned medium to observe its effects on the proliferation of nucleus pulposus cells (NPCs) and the expression of collagen II and MMP3 proteins.

Results

A total of 81 active components were identified in ZQGCD. Following ZQGCD treatment, infiltrating macrophages in intervertebral disc tissues of model rats decreased, the content of M1 macrophages decreased, while the content of M2 macrophages increased, the expression of proinflammatory factors and pain-inducing factors in serum decreased, and the expression of substance P in intervertebral disc tissue decreased. Consequently, the intervertebral disc degeneration and hyperalgesia of rats were improved. In vitro studies revealed that LPS induced M1 macrophage polarization. By inhibiting the JAK2/STAT3 pathway, both JAK2 inhibitors and ZQGCD effectively suppressed M1 polarization, resulting in decreased levels of IL-1β, IL-6, TNF-α, and various other inflammatory factors. Consequently, this inhibition led to a delay in the degeneration of NPCs.

Conclusion

There is macrophage infiltration in the intervertebral disc tissue of IDD rats, and JAK2/STAT3 pathway is activated, macrophages are polarized to M1 type, resulting in inflammatory microenvironment, leading to intervertebral disc degeneration and hyperalgesia. ZQGCD exhibited a delaying effect on IDD and improved hyperalgesia by inhibiting the JAK2/STAT3/macrophage M1 polarization pathway.

Knocking down EGR1 inhibits nucleus pulposus cell senescence and mitochondrial damage through activation of PINK1-Parkin dependent mitophagy, thereby delaying intervertebral disc degeneration

Mitophagy plays a crucial role in maintaining the homeostasis of intervertebral disc (IVD). Early Growth Response 1 (EGR1), a conservative transcription factor, is commonly upregulated under oxidative stress conditions and participates in regulating cellular senescence, apoptosis, and inflammatory responses. However, the specific role of EGR1 in nucleus pulposus (NP) cell senescence and mitophagy remains unclear. In this study, through bioinformatics analysis and validation using human tissue specimens, we found that EGR1 is significantly upregulated in IVD degeneration (IDD). Further experimental results demonstrate that knockdown of EGR1 inhibits TBHP-induced NP cell senescence and mitochondrial dysfunction while promoting the activation of mitophagy. The protective effect of EGR1 knockdown on NP cell senescence and mitochondrion disappears upon inhibition of mitophagy with mdivi1. Mechanistic studies reveal that EGR1 suppresses NP cell senescence and mitochondrial dysfunction by modulating the PINK1-Parkin dependent mitophagy pathway. Additionally, EGR1 knockdown delays acupuncture-induced IDD in rats. In conclusion, our study demonstrates that under TBHP-induced oxidative stress, EGR1 knockdown mitigates NP cell senescence and mitochondrial dysfunction through the PINK1-Parkin dependent mitophagy pathway, thereby alleviating IDD.

Cyclic Mechanism Affects Lumbar Spine Creep Response

PURPOSE

This study aims to explore how cyclic loading influences creep response in the lumbar spine under combined flexion-compression loading.

METHODS

Ten porcine functional spinal units (FSUs) were mechanically tested in cyclic or static combined flexion-compression loading. Creep response between loading regimes was compared using strain-time histories and linear regression. High-resolution computed tomography (µCT) visualized damage to FSUs. Statistical methods, ANCOVA and ANOVA, assessed differences in behavior between loading regimes.

RESULTS

Cyclic and static loading regimes exhibited distinct creep response patterns and biphasic response. ANCOVA and ANOVA analyses revealed significant differences in slopes of creep behavior in both linear phases. Cyclic tests consistently showed endplate fractures in µCT imaging.

CONCLUSION

The study reveals statistically significant differences in creep response between cyclic and static loading regimes in porcine lumbar spinal units under combined flexion-compression loading. The observed biphasic behavior suggests distinct phases of tissue response, indicating potential shifts in load transfer mechanisms. Endplate fractures in cyclic tests suggest increased injury risk compared to static loading. These findings underscore the importance of considering loading conditions in computational models and designing preventive measures for occupations involving repetitive spinal loading.

Tbxt alleviates senescence and apoptosis of nucleus pulposus cells through Atg7-mediated autophagy activation during intervertebral disk degeneration

Intervertebral disk degeneration (IDD) is a significant cause of low back pain, characterized by excessive senescence and apoptosis of nucleus pulposus cells (NPCs). However, the precise mechanisms behind this senescence and apoptosis remain unclear. This study aimed to investigate the role of T-box transcription factor T (Tbxt) in IDD both in vitro and in vivo, using a hydrogen peroxide (H2O2)-induced NPCs senescence and apoptosis model, as well as a rat acupuncture IDD model. First, the expression of p16 and cleaved-caspase 3 significantly increased in degenerated human NPCs, accompanied by a decrease in Tbxt expression. Knockdown of Tbxt exacerbated senescence and apoptosis in the H2O2-induced NPCs degeneration model. Conversely, upregulation of Tbxt alleviated these effects induced by H2O2. Mechanistically, bioinformatic analysis revealed that the direct downstream target genes of Tbxt were highly enriched in autophagy-related pathways, and overexpression of Tbxt significantly activated autophagy in NPCs. Moreover, the administration of the autophagy inhibitor, 3-methyladenine, impeded the impact of Tbxt on the processes of senescence and apoptosis in NPCs. Further investigation revealed that Tbxt enhances autophagy by facilitating the transcription of ATG7 through its interaction with a specific motif within the promoter region. In conclusion, this study suggests that Tbxt mitigates H2O2-induced senescence and apoptosis of NPCs by activating ATG7-mediated autophagy.NEW & NOTEWORTHY This study investigates the role of Tbxt in IDD. The results demonstrate that knockdown of Tbxt exacerbates H2O2-induced senescence and apoptosis in NPCs and IDD, whereas upregulation of Tbxt significantly protects against IDD both in vivo and in vitro. Mechanistically, in the nucleus, Tbxt enhances the transcription of ATG7, leading to increased expression of ATG7 protein levels. This, in turn, promotes elevated autophagy levels, ultimately alleviating IDD.

The positive effect of pulse electromagnetic field therapy on pain and disability in chronic low back pain: a comparative study

BACKGROUND

Low back pain that lasts longer than three months is called chronic low back pain. Chronic low back pain is among the most common problems in the world, causing severe disability and loss of employment in patients.

OBJECTIVE

To investigate the effect of pulse electromagnetic field therapy (PEMFT) added to routine physical therapy on pain and functional status in patients with chronic low back pain.

METHODS

This retrospective comparative study included 69 patients with chronic low back pain. The patients were divided into two groups: those who received lumbar transcutaneous electrical nerve stimulation, infrared, and ultrasound treatments, and those who additionally received PEMFT. The files of patients with chronic low back pain were reviewed, and those who had been evaluated using the Quebec Back Pain Disability Scale (QBPDS) in terms of functional capacity and effects of low back pain and the Visual Analogue Scale (VAS) for pain both before and after treatment were included in the study.

RESULTS

No significant difference was detected between the two groups' pretreatment VAS and QBPDS scores (p > 0.05). The second-and-third measurement scores of both groups were significantly lower than their first-measurement VAS and QBPDS scores (p ˂ 0.001), but there was no significant difference between their second- and third-measurement scores (p > 0.05). According to the inter-group comparison of the VAS and QBPDS scores, the second and third-measurement scores of the PEMFT group were significantly lower than those of the control group (p ˂ 0.001).

CONCLUSIONS

PEMFT seems to be able to alleviate pain intensity and ameliorate disability in patients with chronic low back pain. PEMFT can be considered an effective and safe option that can be added to routine physical therapy modalities for relieving chronic low back pain frequently encountered in clinical practice. Further studies validating the effectiveness of PEMFT could strengthen its position in the management of chronic low back pain.

Glutamine Mitigates Oxidative Stress-Induced Matrix Degradation, Ferroptosis, and Pyroptosis in Nucleus Pulposus Cells via Deubiquitinating and Stabilizing Nrf2

Aims: Intervertebral disc degeneration (IDD) is closely related to low back pain, which is a prevalent age-related problem worldwide; however, the mechanism underlying IDD is unknown. Glutamine, a free amino acid prevalent in plasma, is recognized for its anti-inflammatory and antioxidant properties in various diseases, and the current study aims to clarify the effect and mechanism of glutamine in IDD. Results: A synergistic interplay was observed between pyroptosis and ferroptosis within degenerated human disc specimens. Glutamine significantly mitigated IDD in both ex vivo and in vivo experimental models. Moreover, glutamine protected nucleus pulposus (NP) cells after tert-butyl hydroperoxide (TBHP)-induced pyroptosis, ferroptosis, and extracellular matrix (ECM) degradation in vitro. Glutamine protected NP cells from TBHP-induced ferroptosis by promoting the nuclear factor erythroid 2-related factor 2 (Nrf2) accumulation by inhibiting its ubiquitin-proteasome degradation and inhibiting lipid oxidation. Innovation and Conclusions: A direct correlation is evident in the progression of IDD between the processes of pyroptosis and ferroptosis. Glutamine suppressed oxidative stress-induced cellular processes, including pyroptosis, ferroptosis, and ECM degradation through deubiquitinating Nrf2 and inhibiting lipid oxidation in NP cells. Glutamine is a promising novel therapeutic target for the management of IDD.

Machine Learning Models for Low Back Pain Detection and Factor Identification: Insights From a 6-Year Nationwide Survey

This study aimed to enhance performance, identify additional predictors, and improve the interpretability of biopsychosocial machine learning models for low back pain (LBP). Using survey data from a 6-year nationwide study involving 17,609 adults aged ≥50 years (Korea National Health and Nutrition Examination Survey), we explored 119 factors to detect LBP in individuals who reported experiencing LBP for at least 30 days within the previous 3 months. Our primary model, model 1, employed eXtreme Gradient Boosting (XGBoost) and selected primary factors (PFs) based on their feature importance scores. To extend this, we introduced additional factors, such as lumbar X-ray findings, physical activity, sitting time, and nutrient intake levels, which were available only during specific survey periods, into models 2 to 4. Model performance was evaluated using the area under the curve, with predicted probabilities explained by SHapley Additive exPlanations. Eleven PFs were identified, and model 1 exhibited an enhanced area under the curve .8 (.77-.84, 95% confidence interval). The factors had varying impacts across individuals, underscoring the need for personalized assessment. Hip and knee joint pain were the most significant PFs. High levels of physical activity were found to have a negative association with LBP, whereas a high intake of omega-6 was found to have a positive association. Notably, we identified factor clusters, including hip joint pain and female sex, potentially linked to osteoarthritis. In summary, this study successfully developed effective XGBoost models for LBP detection, thereby providing valuable insight into LBP-related factors. Comprehensive LBP management, particularly in women with osteoarthritis, is crucial given the presence of multiple factors. PERSPECTIVE: This article introduces XGBoost models designed to detect LBP and explores the multifactorial aspects of LBP through the application of SHapley Additive exPlanations and network analysis on the 4 developed models. The utilization of this analytical system has the potential to aid in devising personalized management strategies to address LBP.

Attenuating intervertebral disc degeneration through spermidine-delivery nanoplatform based on polydopamine for persistent regulation of oxidative stress

As one of the most widespread musculoskeletal diseases worldwide, intervertebral disc degeneration (IVDD) remains an intractable clinical problem. Currently, oxidative stress has been widely considered as a significant risk factor in the IVDD pathological changes, and targeting oxidative stress injury to improve the harsh microenvironment may provide a novel and promising strategy for disc repair. It is evident that spermidine (SPD) has the ability to attenuate oxidative stress across several disease models. However, limited research exists regarding its impact on oxidative stress within the intervertebral disc. Moreover, enhancing the local utilization rate of SPD holds great significance in IVDD management. This study aimed to develop an intelligent biodegradable mesoporous polydopamine (PDA) nanoplatform for sustained release of SPD. The obtained PDA nanoparticles with spherical morphology and mesoporous structure released loaded-therapeutic molecules under low pH and H2O2. Combined treatment with SPD loaded into PDA nanoparticles (SPD/PDA) resulted in better therapeutic potential than those with SPD alone on oxidative stress injury. Furthermore, both SPD and SPD/PDA could induce anti-inflammatory M2 macrophage polarization. Upon injection into degenerative IVDs, the SPD/PDA group achieved a good repair efficacy with a long-term therapeutic effect. These findings indicated that the synergized use of SPD with responsive drug delivery nanocarriers may steadily scavenge reactive oxygen species and provide an effective approach toward the treatment of IVDD.

Identification and experimental verification of immune-related hub genes in intervertebral disc degeneration

Background

Inflammation and immune factors are the core of intervertebral disc degeneration (IDD), but the immune environment and epigenetic regulation process of IDD remain unclear. This study aims to identify immune-related diagnostic candidate genes for IDD, and search for potential pathogenesis and therapeutic targets for IDD.

Methods

Gene expression datasets were obtained from the Gene Expression Omnibus (GEO). Differential expression immune genes (Imm-DEGs) were identified through weighted gene correlation network analysis (WGCNA) and linear models for microarray data analysis (Limma). LASSO algorithm was used to identify feature genes related to IDD, which were compared with core node genes in PPI network to obtain hub genes. Based on the coefficients of hub genes, a risk model was constructed, and the diagnostic value of hub genes was further evaluated through receiver operating characteristic (ROC) analysis. Xcell, an immunocyte analysis tool, was used to estimate the infiltration of immune cells. Finally, nucleus pulposus cells were co-cultured with macrophages to create an M1 macrophage immune inflammatory environment, and the changes of hub genes were verified.

Results

Combined with the results of WGCNA and Limma gene differential analysis, a total of 30 Imm-DEGs were identified. Imm-DEGs enriched in multiple pathways related to immunity and inflammation. LASSO algorithm identified 10 feature genes from Imm-DEGs that significantly affected IDD, and after comparison with core node genes in the PPI network of Imm-DEGs, 6 hub genes (NR1H3, SORT1, PTGDS, AGT, IRF1, TGFB2) were determined. Results of ROC curves and external dataset validation showed that the risk model constructed with the 6 hub genes had high diagnostic value for IDD. Immunocyte infiltration analysis showed the presence of various dysregulated immune cells in the degenerative nucleus pulposus tissue. In vitro experimental results showed that the gene expression of NR1H3, SORT1, PTGDS, IRF1, and TGFB2 in nucleus pulposus cells in the immune inflammatory environment was up-regulated, but the change of AGT was not significant.

Conclusions

The hub genes NR1H3, SORT1, PTGDS, IRF1, and TGFB2 can be used as immunorelated biomarkers for IDD, and may be potential targets for immune regulation therapy for IDD.

Transforaminal Steroid Injection After Dorsal Root Ganglion Pulsed Radiofrequency (DRG-PRF): Impact on Pain Intensity and Disability

INTRODUCTION

Dorsal root ganglion pulsed radiofrequency (DRG-PRF) is frequently used for the treatment of chronic lumbar radicular pain with good outcomes in terms of pain management. Transforaminal epidural steroid injection (TFESI) is often administered immediately after DRG-PRF to increase the anti-inflammatory effects, but support for the synergic mechanism is lacking in the literature. The aim of this study was to investigate the potential role of TFESI immediately after DRG-PRF and its possible role on pain intensity and patient disability.

METHODS

A database of patients who underwent DRG-PRF with or without TFESI immediately after DRG-PRF was retrospectively analysed; propensity score matching was applied to the analysis to reduce possible bias. Pain intensity (numerical rating scale [NRS]) and Oswestry disability index (ODI) were recorded pre-operatively and at the 1- and 3-month follow-up in the two groups of patients.

RESULTS

A total of 252 patients were included in this retrospective analysis, 126 patients in the DRG-PRF + TFESI group and 126 patients in the DRG-PRF group after propensity score matching. Both groups displayed a significant reduction in pain intensity (NRS score reduction; p < 0.0001) and improvement in the ODI (p < 0.0001) from baseline at the 3-month follow-up. Interestingly, the use of TFESI after DRG-PRF was not associated with any clinical benefit as no difference in NRS and ODI was found between the two groups at the 1- and 3-month follow-ups.

CONCLUSIONS

Our study revealed a significant pain reduction and disability improvement after DRG-PRF in patients with lumbar radicular pain. Interestingly, no positive role of TFESI immediately after DRG-PRF was observed. These findings suggest that DRG-PRF provides substantial pain relief, and no added benefit is obtained with subsequent steroid injection. Future prospective studies with expanded follow-up periods are needed to confirm these findings.

Isorhapontigenin delays senescence and matrix degradation of nucleus pulposus cells via PI3K/AKT/mTOR-mediated autophagy pathway in vitro and alleviates intervertebral disc degeneration in vivo

Intervertebral disc degeneration (IVDD), a common degenerative disc disease, is a major etiological factor for back pain, affecting a significant number of middle-aged and elderly individuals worldwide. Thus, IVDD is a major socio-economic burden. The factors contributing to the complex IVDD etiology, which has not been elucidated, include inflammation, oxidative stress, and natural aging. In particular, inflammation and aging of nucleus pulposus cells are considered primary pathogenic factors. Isorhapontigenin (ISO) is a polyphenolic compound commonly found in traditional Chinese herbs and grapes. We have demonstrated that ISO exerts anti-inflammatory and anti-aging effects and mitigates extracellular matrix (ECM) degradation. In this study, in vitro experiments revealed that, ISO delays aging and ECM degradation by promoting PI3K/AKT/mTOR-mediated autophagy. Meanwhile, in vivo experiments affirmed that ISO delays the progression of IVDD.

An Optimized CT Protocol for Detecting Suspected Cauda Equina Syndrome: A Comparative Analysis with MRI

BACKGROUND AND PURPOSE

Lumbar disc herniation, potentially leading to nerve root compression and cauda equina syndrome, is typically evaluated using MR imaging. However, the limited availability of MR imaging outside regular hours in certain health care systems poses considerable challenges. This purpose of this study was to prospectively evaluate the diagnostic accuracy of an optimized CT lumbar spine protocol as a potential alternative to MR imaging in assessing suspected neural compression.

MATERIALS AND METHODS

Patients presenting to the emergency department with suspected cauda equina syndrome or acute radicular symptoms secondary to lumbar disc herniation referred for MR imaging were prospectively enrolled for an additional CT optimized to assess spinal stenosis. An expert radiologist, blinded to clinical data, graded canal stenosis at each lumbar level on CT. The same grading process was applied to MR imaging after a 4-week interval to maintain blinding.

RESULTS

Fifty-nine individuals were included in the final analysis. In 22 (39%) cases, no significant stenosis was identified. In a further 22 (37%) cases, disc pathology was identified that was managed conservatively. Thirteen (22%) individuals proceeded to urgent surgical decompression. In 1 (2%) instance, an alternative diagnosis was identified. Compared with MR imaging, the sensitivity, specificity, and positive and negative predictive values for CT in detecting disc pathology in patients presenting with symptoms suggestive of acute neural compression were 97% (95% CI, 82%-99%), 97% (95% CI, 83%-99%), 97% (95% CI, 92%-99%), and 97% (95% CI, 83%-99%), respectively. CT accurately identified all cases requiring urgent decompression.

CONCLUSIONS

CT accurately predicted MR imaging findings in patients with suspected cauda equina and nerve root compression, demonstrating its utility as an adjunct tool for patient triage in emergency settings with limited MR imaging access. This protocol could enhance the allocation of emergency resources by appropriately selecting patients for emergent MR imaging.

The regulatory mechanism of cyclic GMP-AMP synthase on inflammatory senescence of nucleus pulposus cell

BACKGROUND

Cellular senescence features irreversible growth arrest and secretion of multiple proinflammatory cytokines. Cyclic GMP-AMP synthase (cGAS) detects DNA damage and activates the DNA-sensing pathway, resulting in the upregulation of inflammatory genes and induction of cellular senescence. This study aimed to investigate the effect of cGAS in regulating senescence of nucleus pulposus (NP) cells under inflammatory microenvironment.

METHODS

The expression of cGAS was evaluated by immunohistochemical staining in rat intervertebral disc (IVD) degeneration model induced by annulus stabbing. NP cells were harvested from rat lumbar IVD and cultured with 10ng/ml IL-1β for 48 h to induce premature senescence. cGAS was silenced by cGAS specific siRNA in NP cells and cultured with IL-1β. Cellular senescence was evaluated by senescence-associated beta-galactosidase (SA-β-gal) staining and flow cytometry. The expression of senescence-associated secretory phenotype including IL-6, IL-8, and TNF-a was evaluated by ELISA and western blotting.

RESULTS

cGAS was detected in rat NP cells in cytoplasm and the expression was significantly increased in degenerated IVD. Culturing in 10ng/ml IL-1β for 48 h induced cellular senescence in NP cells with attenuation of G1-S phase transition. In senescent NP cells the expression of cGAS, p53, p16, NF-kB, IL-6, IL-8, TNF-α was significantly increased while aggrecan and collagen type II was reduced than in normal NP cells. In NP cells with silenced cGAS, the expression of p53, p16, NF-kB, IL-6, IL-8, and TNF-α was reduced in inflammatory culturing with IL-1β.

CONCLUSION

cGAS was increased by NP cells in degenerated IVD promoting cellular senescence and senescent inflammatory phenotypes. Targeting cGAS may alleviate IVD degeneration by reducing NP cell senescence.

A novel simplified sonographic approach with fluoroscopy-controlled L5 transforaminal epidural injections in patients with high iliac crest: a retrospective study

BACKGROUND

To explore a novel ultrasound (US) modality for lumbar transforaminal epidural injections (TFEIs) in patients with low back pain (LBP) and L5 radicular pain combined with high iliac crest (HIC).

METHODS

One-hundred and forty-one patients were retrospectively stratified into two groups based on the treatment they received: novel group, receiving US-guided and fluoroscopy (FL)-controlled TFEIs using a sagittal oblique approach between the superior articular process of L5 and S1, and control group, receiving US-guided TFEIs with conventional transverse approach combined with FL confirmation. Accuracy of contrast dispersing into lumbar epidural space was set as the primary endpoint. Radiation dosages, procedure time, numeric rating scale (NRS) scores, Modified Oswestry Disability Questionnaire (MODQ) scores, adverse events, and rescue analgesic requirement were also recorded. The generalized liner mixed model (GLMMs) was employed to compare the repeatedly measured variables between groups, taking individual confounding factors as covariance.

RESULTS

The accuracy of TFEIs was 92.8% and 65.2% in novel and control group, with a significant difference of 26.7% (95% CI: 15.4%, 39.8%) between two modalities (p < 0.001). Significant pain relief was observed in novel group as opposed to control group after one injection. Procedure time in novel group (8.4 ± 1.6 min) was shorter than control group (15.8 ± 3.5 min) (p < 0.001) with less radiation dosage (3047 ± 5670 vs. 8808 ± 1039 μGy/m2, p < 0.001). Significantly, lower incidence of L5 paresthesia occurred in novel group. Statistical differences of NRS scores between the novel and control group were reached at 1 week after procedure (1 (IQR: - 1-3) vs. 3 (IQR: - 1-7), p = 0.006), while not reached at both 1- (1 (IQR: 0-2) vs. 1 (IQR: - 1-3), p = 0.086) or 3-month follow-up (0 (IQR: - 1-1) vs. 1 (IQR: 0-2), p = 0.094). Both groups showed similar functional improvement (F = 0.103, p = 0.749) during follow-up.

CONCLUSIONS

The novel sonographic technique provided superior accuracy needle placement and better pain-relieving effect through one injection as compared to the routine transverse approach. Consequently, in situations where the HIC imposed limitations for TFEIs performance on L5, the novel technique should be recommended to consider increasing accurate puncture, minimizing radiation exposure, consuming procedure time, and reducing the risk of neuraxial injury.

Identification of core genes in intervertebral disc degeneration using bioinformatics and machine learning algorithms

Background

Intervertebral Disc Degeneration (IDD) is a major cause of lower back pain and a significant global health issue. However, the specific mechanisms of IDD remain unclear. This study aims to identify key genes and pathways associated with IDD using bioinformatics and machine learning algorithms.

Methods

Gene expression profiles, including those from 35 LDH patients and 43 healthy volunteers, were downloaded from the GEO database (GSE124272, GSE150408, GSE23130, GSE153761). After merging four microarray datasets, differentially expressed genes (DEGs) were selected for GO and KEGG pathway enrichment analysis. Weighted Gene Co-expression Network Analysis (WGCNA) was then applied to the merged dataset to identify relevant modules and intersect with DEGs to discover candidate genes with diagnostic value. A LASSO model was established to select appropriate genes, and ROC curves were drawn to elucidate the diagnostic value of genetic markers. A Protein-Protein Interaction (PPI) network was constructed and visualized to determine central genes, followed by external validation using qRT-PCR.

Results

Differential analysis of the preprocessed dataset identified 244 genes, including 183 upregulated and 61 downregulated genes. WGCNA analysis revealed the most relevant module intersecting with DEGs, yielding 9 candidate genes. The lasso-cox method was used for regression analysis, ultimately identifying 6 genes: ASPH, CDC42EP3, FOSL2, IL1R1, NFKBIZ, TCF7L2. A Protein-Protein Interaction (PPI) network created with GENEMANIA identified IL1R1 and TCF7L2 as central genes.

Conclusion

Our study shows that IL1R1 and TCF7L2 are the core genes of IDD, offering new insights into the pathogenesis and therapeutic development of IDD.

A comparison of ultrasound volume navigation, O-arm navigation, and X-ray guidance for screw placement in minimally invasive transforaminal lumbar interbody fusion: a randomized controlled trial

OBJECTIVE

To compare the differences between Ultrasound Volume Navigation (UVN), O-arm Navigation, and conventional X-ray fluoroscopy-guided screw placement in Minimally Invasive Transforaminal Lumbar Interbody Fusion (MIS-TLIF) surgeries.

METHODS

A total of 90 patients who underwent MIS-TLIF due to lumbar disc herniation from January 2022 to January 2023 were randomly assigned to the UVN group, O-arm group, and X-ray group. UVN, O-arm navigation, and X-ray guidance were used for screw placement in the respective groups, while the remaining surgical procedures followed routine MIS-TLIF protocols. Intraoperative data including average single screw placement time, total radiation dose, and average effective radiation dose per screw were recorded and calculated. On the 10th day after surgery, postoperative X-ray and CT examinations were conducted to assess screw placement accuracy and facet joint violation.

RESULTS

There were no significant differences in general characteristics among the three groups, ensuring comparability. Firstly, the average single screw placement time in the O-arm group was significantly shorter than that in the UVN group and X-ray group (P<0.05). Secondly, in terms of total radiation dose during surgery, for single-level MIS-TLIF, the O-arm group had a significantly higher radiation dose compared to the UVN group and X-ray group (P<0.05). However, for multi-level MIS-TLIF, the X-ray group had a significantly higher radiation dose than the O-arm group and UVN group (P<0.05). In terms of average single screw radiation dose, the O-arm group and X-ray group were similar (P>0.05), while the UVN group was significantly lower than the other two groups (P<0.05). Furthermore, no significant differences were found in screw placement assessment grades among the three groups (P>0.05). However, in terms of facet joint violation rate, the UVN group (10.3%) and O-arm group (10.7%) showed no significant difference (P>0.05), while the X-ray group (26.7%) was significantly higher than both groups (P<0.05). Moreover, in the UVN group, there were significant correlations between average single screw placement time and placement grade with BMI index (r = 0.637, P<0.05; r = 0.504, P<0.05), while no similar significant correlations were found in the O-arm and X-ray groups.

CONCLUSION

UVN-guided screw placement in MIS-TLIF surgeries demonstrates comparable efficiency, visualization, and accuracy to O-arm navigation, while significantly reducing radiation exposure compared to both O-arm navigation and X-ray guidance. However, UVN may be influenced by factors like obesity, limiting its application.

Paravertebrally-Injected Multifunctional Hydrogel for Sustained Anti-Inflammation and Pain Relief in Lumbar Disc Herniation

Pain caused by lumbar disc herniation (LDH) severely compromises patients' quality of life. The combination of steroid and local anesthetics is routinely employed in clinics to alleviate LDH-induced pain. However, the approach only mediates transient efficacy and requires repeated and invasive lumbar epidural injections. Here a paravertebrally-injected multifunctional hydrogel that can efficiently co-load and controlled release glucocorticoid betamethasone and anesthetics ropivacaine for sustained anti-inflammation, reactive oxygen species (ROS)-removal and pain relief in LDH is presented. Betamethasone is conjugated to hyaluronic acid (HA) via ROS-responsive crosslinker to form amphiphilic polymer that self-assemble into particles with ropivacaine loaded into the core. Solution of drug-loaded particles and thermo-sensitive polymer rapidly forms therapeutic hydrogel in situ upon injection next to the herniated disc, thus avoiding invasive epidural injection. In a rat model of LDH, multifunctional hydrogel maintains the local drug concentration 72 times longer than free drugs and more effectively inhibits the expression of pro-inflammatory cytokines and pain-related molecules including cyclooxygenase-2 (COX-2) and prostaglandin E2 (PGE2). Therapeutic hydrogel suppresses the LDH-induced pain in rats for 12 days while the equivalent dose of free drugs is only effective for 3 days. This platform is also applicable to ameliorate pain caused by other spine-related diseases.

Self-powered triboelectric-responsive microneedles with controllable release of optogenetically engineered extracellular vesicles for intervertebral disc degeneration repair

Excessive exercise is an etiological factor of intervertebral disc degeneration (IVDD). Engineered extracellular vesicles (EVs) exhibit excellent therapeutic potential for disease-modifying treatments. Herein, we fabricate an exercise self-powered triboelectric-responsive microneedle (MN) assay with the sustainable release of optogenetically engineered EVs for IVDD repair. Mechanically, exercise promotes cytosolic DNA sensing-mediated inflammatory activation in senescent nucleus pulposus (NP) cells (the master cell population for IVD homeostasis maintenance), which accelerates IVDD. TREX1 serves as a crucial nuclease, and disassembly of TRAM1-TREX1 complex disrupts the subcellular localization of TREX1, triggering TREX1-dependent genomic DNA damage during NP cell senescence. Optogenetically engineered EVs deliver TRAM1 protein into senescent NP cells, which effectively reconstructs the elimination function of TREX1. Triboelectric nanogenerator (TENG) harvests mechanical energy and triggers the controllable release of engineered EVs. Notably, an optogenetically engineered EV-based targeting treatment strategy is used for the treatment of IVDD, showing promising clinical potential for the treatment of degeneration-associated disorders.

The role of melatonergic system in intervertebral disc degeneration and its association with low back pain: a clinical study

Objective

The mechanisms of intervertebral disc degeneration (IVDD) in low back pain (LBP) patients are multiples. In this study, we attempt to investigate whether melatonergic system plays a potential role in IVDD patients with LBP by analyzing their clinical specimens. The fucus will be given to the correlation between the melatonin receptor expression and intervertebral disc tissue apoptosis.

Methods

In this clinical study, 107 lumbar intervertebral disc nucleus pulposus (NP) specimens from patients with LBP were collected with patients' consents. The disc height (DH) discrepancy ratio, range of motion and sagittal parameters of the pathological plane were measured and Pfirrmann grade was used to classified the grades of IVDD level. Discs at grades 1-3 were served as normal control and grades 4-5 were considered as IVDD. The expression levels of melatonin receptor 1A (MT1) and 1B (MT2) were measured by immunohistochemistry. The apoptosis of NP was assessed using TUNEL staining. Their potential associations among MT1/2, DH, apoptosis, sagittal parameters with IVDD and LBP were evaluated with statistical analysis.

Results

The incidence of IVDD was positively associated with age and negatively related to VAS scores for LBP (p < 0.001). Patients with higher degree of IVDD also have higher DH discrepancy ratio (p < 0.001), higher prevalence of lumbar instability (p = 0.003) and higher cell apoptosis compared to the control. Nevertheless, no statistically significant correlation was identified between Pfirrmann grade and lumbar sagittal parameters. MT1 and MT2 both were highly expressed in the NP tissues. Importantly, MT1 expression but not MT2 was significantly increased in the intervertebral disc tissue of patients with IVDD and its level correlated well with cell apoptosis level and the severity of IVDD as well as lower VAS scores for LBP.

Conclusion

The highly elevated MT1 expression was found in NP tissues of patients with IVDD and LBP compared to the control. This phenomenon probably reflects the compensating response of the body to the pathological alteration of the IVDD and LBP. Therefore, these findings provide the novel information to use selective agonists of MT1 to target IVDD and LBP clinically.

Hypoxia-Preconditioned BMSC-Derived Exosomes Induce Mitophagy via the BNIP3-ANAX2 Axis to Alleviate Intervertebral Disc Degeneration

Intervertebral disc degeneration (IVDD) is a chronic degenerative disease involving the aging and loss of proliferative capacity of nucleus pulposus cells (NPCs), processes heavily dependent on mitochondrial dynamics and autophagic flux. This study finds that the absence of BCL2/adenovirus E1B 19 kDa interacting protein 3 (BNIP3) is associated with senescence-related NPC degeneration, disrupting mitochondrial quality control. Bone marrow mesenchymal stem cells (BMSCs) have multidirectional differentiation potential and produce extracellular vesicles containing cellular activators. Therefore, in this study, BMSCs are induced under hypoxic stimulation to deliver BNIP3-rich extracellular vesicles to NPCs, thereby alleviating aging-associated mitochondrial autophagic flux, promoting damaged mitochondrial clearance, and restoring mitochondrial quality control. Mechanistically, BNIP3 is shown to interact with the membrane-bound protein annexin A2 (ANXA2), enabling the liberation of the transcription factor EB (TFEB) from the ANXA2-TFEB complex, promoting TFEB nuclear translocation, and regulating autophagy and lysosomal gene activation. Furthermore, a rat model of IVDD is established and verified the in vivo efficacy of the exosomes in repairing disc injuries, delaying NPC aging, and promoting extracellular matrix (ECM) synthesis. In summary, hypoxia-induced BMSC exosomes deliver BNIP3-rich vesicles to alleviate disc degeneration by activating the mitochondrial BNIP3/ANXA2/TFEB axis, providing a new target for IVDD treatment.

Is Type 2 Diabetes Mellitus Associated with Spinal Degenerative Disorders?: Evidence from Observational and 2-Sample Mendelian Randomization Analyses

BACKGROUND

Type 2 diabetes mellitus (T2DM) and spinal degenerative disorders (SDD) are common diseases that frequently coexist. However, both traditional observational studies and recent Mendelian randomization (MR) studies have demonstrated conflicting evidence on the association between T2DM and SDD. This comparative study explored and compared the association between T2DM and SDD using observational and MR analyses.

METHODS

For observational analyses, cross-sectional studies (44,972 participants with T2DM and 403,095 participants without T2DM), case-control studies (38,234 participants with SDD and 409,833 participants without SDD), and prospective studies (35,550 participants with T2DM and 392,046 participants without T2DM with follow-up information until 2022) were performed to test the relationship between T2DM and SDD using individual-level data from the U.K. Biobank from 2006 to 2022. For MR analyses, the associations between single-nucleotide polymorphisms with SDD susceptibility obtained using participant data from the U.K. Biobank, which had 407,938 participants from 2006 to 2022, and the FinnGen Consortium, which had 227,388 participants from 2017 to 2022, and genetic predisposition to T2DM obtained using summary statistics from a pooled genome-wide association study involving 1,407,282 individuals were examined. The onset and severity of T2DM are not available in the databases being used.

RESULTS

Participants with T2DM were more likely to have SDD than their counterparts. Logistic regression analysis identified T2DM as an independent risk factor for SDD, which was confirmed by the Cox proportional hazard model results. However, using single-nucleotide polymorphisms as instruments, the MR analyses demonstrated no causal relationship between T2DM and SDD. The lack of such an association was robust in the sensitivity analysis, and no pleiotropy was seen.

CONCLUSIONS

Our results suggest that the association between T2DM and SDD may be method-dependent. Researchers and clinicians should be cautious in interpreting the association, especially the causal association, between T2DM and SDD. Our findings provide fresh insights into the association between T2DM and SDD by various analysis methods and guide future research and clinical efforts in the effective prevention and management of T2DM and SDD.

LEVEL OF EVIDENCE

Prognostic Level III. See Instructions for Authors for a complete description of levels of evidence.

Relation Between Abnormal Spontaneous Brain Activity and Altered Neuromuscular Activation of Lumbar Paraspinal Muscles in Chronic Low Back Pain

OBJECTIVE

To investigate the neural mechanism underlying functional reorganization and motor coordination strategies in patients with chronic low back pain (cLBP).

DESIGN

A case-control study based on data collected during routine clinical practice.

SETTING

This study was conducted at a university hospital.

PARTICIPANTS

Fifteen patients with cLBP and 15 healthy controls.

INTERVENTIONS

Not applicable.

MAIN OUTCOME MEASURES

Whole brain blood oxygen level-dependent signals were measured using functional magnetic resonance imaging and amplitude of low-frequency fluctuation (ALFF) method to identify pain-induced changes in regional spontaneous brain activity. A novel approach based on the surface electromyogram (EMG) system and fine-wire electrodes was used to record EMG signals in the deep multifidus, superficial multifidus, and erector spinae.

RESULTS

In cLBP, compared with healthy groups, ALFF was higher in the medial prefrontal, primary somatosensory, primary motor, and inferior temporal cortices, whereas it was lower in the cerebellum and anterior cingulate and posterior cingulate cortices. Furthermore, the decrease in the average EMG activity of the 3 lumbar muscles in the cLBP group was positively correlated with the ALFF values of the primary somatosensory cortex, motor cortex, precuneus, and middle temporal cortex but significantly negatively correlated with the ALFF values of the medial prefrontal and inferior temporal cortices. Interestingly, the correlation between the functional activity in the cerebellum and the EMG activity varied in the lumbar muscles.

CONCLUSIONS

These findings suggest a functional association between changes in spontaneous brain activity and altered voluntary neuromuscular activation patterns of the lumbar paraspinal muscles, providing new insights into the mechanisms underlying pain chronicity as well as important implications for developing novel therapeutic targets of cLBP.

Sugar-sweetened beverage intake and chronic low back pain

Background

The consumption of sugar-sweetened beverages (SSBs) has become a major public health problem globally. However, no studies have specifically examined the relationship between SSB intake and chronic low back pain (CLBP). Therefore, the present study aimed to investigate the relationship between SSB intake and the risk of CLBP.

Methods

This cross-sectional study enrolled participants aged 20 to 69 from the National Health and Nutrition Examination Survey. CLBP was defined as persistent LBP for a consecutive three-month period. Furthermore, SSB intake was assessed and calculated based on dietary recall interviews. Moreover, survey-weighted logistic regression models were employed to evaluate the association between SSB intake and the risk of CLBP, while the restricted cubic spline (RCS) analysis was used to determine whether there were nonlinear associations between SSB intake and CLBP risk. In addition, subgroup analysis was performed using stratification and interaction analysis for all covariates.

Results

A total of 4,146 participants (mean age: 43.405 years) were enrolled in the final analysis. The results of survey-weighted logistic regression models showed that SSB consumption was significantly associated with an increased risk of CLBP among individuals aged 20 to 69 years. Moreover, the results of subgroup analysis and interaction analysis demonstrated that the association between SSB intake and the risk of CLBP was modified by smoking status and hypertension. Specifically, the SSB intake-associated CLBP risk was more pronounced among current smokers or individuals with hypertension.

Conclusion

Reduction of SSB consumption might contribute to the prevention of CLBP for individuals aged 20 to 69 years. Moreover, current smokers or individuals with hypertension should be more vigilant about the SSB intake-associated CLBP risk. Nevertheless, caution should be exercised when interpreting the results of this study, as further research is necessary to explore the association between SSB consumption and CLBP, given the limitations of the current study.

Investigating the characteristics of mild intervertebral disc degeneration at various age stages using single-cell genomics

Introduction: Intervertebral disc degeneration often occurs in the elderly population, but in recent years, there has been an increasing incidence of disc degeneration in younger individuals, primarily with mild degeneration. Methods: In order to explore the underlying mechanisms of disc degeneration in both young and aging individuals, we collected four types of nucleus pulposus (NP) single-cell sequencing samples for analysis based on Pfirrmann grading: normal-young (NY) (Grade I), normal-old (NO) (Grade I), mild degenerative-young (MY) (Grade II-III), and mild degenerative-old (MO) (Grade II-III). Results: We found that most NP cells in NO and MY samples exhibited oxidative stress, which may be important pathogenic factors in NO and MY groups. On the other hand, NP cells in MO group exhibited endoplasmic reticulum stress. In terms of inflammation, myeloid cells were mainly present in the degenerative group, with the MY group showing a stronger immune response compared to the MO group. Interestingly, dendritic cells in the myeloid lineage played a critical role in the process of mild degeneration. Discussion: Our study investigated the molecular mechanisms of intervertebral disc degeneration from an age perspective, providing insights for improving treatment strategies for patients with disc degeneration at different age groups.

Associations between adverse childhood experiences and pain in middle-aged and older adults: findings from the China Health and Retirement Longitudinal Study

OBJECTIVE

Adverse childhood experiences (ACEs) have been associated with a range of adverse health outcomes, with pain being potentially one of them. This population-based cross-sectional study aimed to investigate the associations between Adverse Childhood Experiences (ACEs) and pain in Chinese adults and evaluate whether physical activity and demographic and socioeconomic characteristics modify this associations.

METHODS

Cross-sectional data from the China Health and Retirement Longitudinal Study (CHARLS), were utilized in this study. A total of 9923 respondents with information on 12 ACE indicators and 15 self-reported body pains were included. Logistic regression models were used to assess associations of the ACEs and pain. Modification of the associations by physical activity, demographic and socioeconomic characteristics was assessed by stratified analyses and tests for interaction.

RESULTS

Among the 9923 individuals included in the primary analyses, 5098 (51.4%) males and the mean (SD) age was 61.18 (10·.44) years. Compared with individuals with 0 ACEs, those who with ≥ 5 ACEs had increased risk of single pains and multiple pain. A dose-response association was found between the number of ACEs and the risk of pain (e.g. neck pain for ≥ 5 ACEs vs. none: OR, 1.107; 95% CI, 0.903-1.356; p < 0.001 for trend). In the associations of each body pain with each ACE indicator, most ACE indicators were associated with an increased risk of pain. In addition, physical activity, sociodemographic and socioeconomic characteristics, such as age, sex, educational level, area of residence, childhood economic hardship, did not demonstrate a significant modify on the associations between ACEs and pain.

CONCLUSIONS

These findings indicate that cumulative ACE exposure is associated with increased odds of self-reported pain in Chinese adults, regardless of adult physical activity, sociodemographic and socioeconomic characteristics.

Unraveling the Left-Right Judgment Task in Chronic Low Back Pain: Insights Through Behavioral, Electrophysiological, Motor Imagery, and Bodily Disruption Perspectives

Bodily disruptions have been consistently demonstrated in individuals with chronic low back pain. The performance on the left-right judgment task has been purposed as an indirect measure of the cortical proprioceptive representation of the body. It has been suggested to be dependent on implicit motor imagery, although the available evidence is conflicting. Hence, the aim of this case-control observational study was to examine the performance (accuracy and reaction times) and event-related potentials while performing the left-right judgment task for back and hand images in individuals with chronic low back pain versus healthy controls, along with its relationship with self-reported measurements and quantitative sensory testing. While self-reported data suggested bodily disruptions in the chronic low back pain sample, this was not supported by quantitative sensory testing. Although both groups displayed the same performance, our results suggested an increased attentional load on participants with chronic low back pain to achieve equal performance, measured by a higher N1 peak amplitude in occipital electrodes, especially when the effect of contextual images arises. The absence of differences in the reaction times for the left-right judgment task between both groups, along with inconsistencies in self-reported and quantitative sensory testing data, could question the involvement of implicit motor imagery in solving the task. In conclusion, our results suggest disrupted attentional processing in participants with chronic low back pain to solve the left-right judgment task. PERSPECTIVE: Although there are no differences in the performance of the left-right judgment task (hits, reaction times) between chronic low back pain patients and controls, the analysis of event-related potentials revealed that patients require a higher cognitive load, measured by N1 peak amplitude.

Work-related back pain among diagnostic radiographers in Ghana: A qualitative study

INTRODUCTION

Work-related back pain has a major impact on diagnostic radiographers' clinical task performance in terms of sickness absenteeism, disability and loss of productivity due to presenteeism. However, there is limited information about the burden of work-related back pain among diagnostic radiographers in Ghana. The aim was to explore diagnostic radiographers' experiences of work-related back pain in Ghana.

METHODS

An exploratory-descriptive qualitative study using semi-structured telephone interviews was conducted. Purposive and snowball sampling techniques were used to recruit participants. The interviews were facilitated by an interview guide. Thematic network approach was used to analyse the data.

RESULTS

Eighteen participants, with 14 males and 4 females were interviewed. The mean age of the participants was 31.7 ± 7.3 years. Three themes were developed: increasing burden of work-related back pain; making sense of the multifaceted risk factors for work-related back pain; and preventing work-related back pain. Low back pain was the most common, followed by neck pain with thoracic pain as the least common reported work-related back pain by participants. Identified risk factors included: physical factors; environmental ergonomic factors; and psychosocial factors. Prevention strategies identified were categorised into: health and safety training; creating lifting team; leadership support from diagnostic imaging managers; participatory ergonomics; workforce planning and scheduling; mindfulness exercises; and physical rehabilitation.

CONCLUSION

Assessing the level of ergonomic risks is critical to identifying, analysing and controlling workplace risk factors that can lead to work-related back pain among diagnostic radiographers. Future research is recommended to design and evaluate a multicomponent ergonomic intervention for the prevention of work-related back pain among diagnostic radiographers to enable them deliver care safely and healthily.

IMPLICATIONS FOR PRACTICE

Understanding diagnostic radiographers experiences of work-related back pain can help develop effective strategies to reduce the growing burden of pain back.

Identification and validation of ferroptosis-related lncRNA signature in intervertebral disc degeneration

Low back pain influences people of every age and is one of the major contributors to the global cost of illness. Intervertebral disc degeneration (IVDD) is a major contributor to low back pain, but its pathogenesis is unknown. Recently, ferroptosis has been shown to have a substantial role in modulating IVDD progression. However, the function of ferroptosis-related long non-coding RNAs (lncRNAs) has rarely been reported in IVDD. Consequently, the research was conducted to explore the ferroptosis-related lncRNA signature in the IVDD occurrence and development. We analyzed two datasets (GSE167199 and GSE167931) archived in the NCBI Gene Expression Omnibus (GEO) public database. We screened differentially expressed genes (DEGs) and differentially expressed lncRNAs (DELncs) in these datasets using the limma package. Ferroptosis-related genes (FRGs) were derived from the FerrDb V2 website and the intersection of DEGs and FRGs was considered as differentially expressed ferroptosis-related genes (DFGs). These genes were then subjected to Gene Ontology and Kyoto Encyclopedia of Genes and Genomes analysis. Correlations between DFGs and DELncs were shown by Pearson test to determine differential expression of ferroptosis-related lncRNAs. The Pearson test showed that CPEB1-HTR2A-AS1 and ACSL3-DNAJC27-AS1 pairs had correlation coefficients over 0.9. Twenty ferroptosis-related lncRNAs were identified and validated in IVDD. Eight of these lncRNAs were upregulated in IVDD nucleus pulposus cells, including HTR2A-AS1, MIF-AS1, SLC8A1-AS1, LINC00942, DUXAP8, LINC00161, LUCAT1 and LINC01615. Twelve were downregulated in IVDD nucleus pulposus cells, including DNAJC27-AS1, H19, LINC01588, LINC02015, FLNC1, CARMN, PRKG1-AS1, APCDD1L-DT, LINC00839, LINC00536, LINC00710 and LINC01535. Eighteen of the 20 lncRNAs (excluding H19 and LUCAT1) were identified as ferroptosis-related lncRNAs for the first time and verified in IVDD. We have identified a ferroptosis-related lncRNA signature involved in IVDD and revealed a close relationship between CPEB1 and HTR2A-AS1, and between ACSL3 and DNAJC27-AS1. Our findings indicate that ferroptosis-related lncRNAs are a new target set for the early detection and therapy of IVDD.

M2 Macrophage-Derived Small Extracellular Vesicles Ameliorate Pyroptosis and Intervertebral Disc Degeneration

Intervertebral discs (IVDs) have a limited self-regenerative capacity and current strategies for IVD regeneration are unsatisfactory. Recent studies showed that small extracellular vesicles derived from M2 macrophage cells (M2-sEVs) inhibited inflammation by delivery of various bioactive molecules to recipient cells, which indicated that M2-sEVs may offer a therapeutic strategy for the repair of IVDs. Herein, we investigated the roles and mechanisms of M2-sEVs on IVD regeneration. The in vitro results demonstrated that M2-sEVs inhibited pyroptosis, preserved cellular viability, and promoted migration of nucleus pulposus cells (NPCs). Bioinformatics analysis and verification experiments of microRNA (miR) expression showed that miR-221-3p was highly expressed in M2-sEVs. The mechanism of action was explored and indicated that M2-sEVs inhibited pyroptosis of NPCs through transfer of miR-221-3p, which suppressed the expression levels of phosphatase and tensin homolog and NOD-, LRR-, and pyrin domain-containing protein 3. Moreover, we fabricated decellularized ECM-hydrogel (dECM) for sustained release of M2-sEVs, which exhibited biocompatibility and controlled release properties. The in vivo results revealed that dECM-hydrogel containing M2-sEVs (dECM/M2-sEVs) delayed the degeneration of intervertebral disc degeneration (IDD) models. In addition to demonstrating a promising therapeutic for IDD, this study provided valuable data for furthering the understanding of the roles and mechanisms of M2-sEVs in IVD regeneration.

Comparing the Efficacy and Safety of Unilateral Biportal Endoscopic Decompression with Percutaneous Endoscopic Lumbar Decompression for Lumbar Degenerative Diseases: A Meta-Analysis

OBJECTIVE

Unilateral biportal endoscopic decompression (UBED) offers the advantages of minimal tissue damage, operational flexibility, and clear visualization, positioning it as an innovative and minimally invasive endoscopic technique. Nevertheless, the clinical evidence supporting the use of UBED in the treatment of degenerative lumbar diseases is limited and conflicting.

METHODS

As of October 1, 2023, a comprehensive search was conducted across databases including Web of Science, PubMed, Embase, and the Cochrane Library to identify all published studies on minimally invasive UBED for the treatment of degenerative lumbar diseases. Data pertaining to patient demographics, fluoroscopy time, operative duration, intraoperative hemorrhage, hospitalization length, visual analog scale (VAS) score for back and leg pain, MacNab criteria, Oswestry Disability Index (ODI), and complication rates were extracted. The Newcastle-Ottawa scale was utilized to assess the quality.

RESULTS

Twelve articles were included, involving 816 patients. The back VAS score (95% confidence interval [CI]: -0.09-0.07, P = 0.75), MacNab criteria (95% CI: 0.52-2.3, P = 0.82), fluoroscopy time (95% CI: -7.03 to -0.4, P = 0.08), and the incidence of complications (95% CI: 0.5-1.73, P = 0.82) were not significantly different, while the leg VAS score (95% CI: 0.01-0.18, P = 0.03), ODI score (95% CI: -1.03 to -0.09, P = 0.02), operation time (95% CI: 5.76-20.62, P = 0.0005), hospitalization length (95% CI: 0.41-2.76, P = 0.008), and intraoperative hemorrhage (95% CI: 21.92-72.44, P = 0.0003) were significantly different.

CONCLUSIONS

UBED offers superiority in ODI, flexibility, and visual field clarity. Conversely, percutaneous endoscopic lumbar decompression presents advantages in terms of operation duration, blood loss, hospitalization length, and leg VAS score. These factors should be thoroughly considered when selecting a surgical approach.

Thread-structural microneedles loaded with engineered exosomes for annulus fibrosus repair by regulating mitophagy recovery and extracellular matrix homeostasis

Low back pain is among the most grave public health concerns worldwide and the major clinical manifestation of intervertebral disc degeneration (IVDD). The destruction of annulus fibrosus (AF) is the primary cause of IVDD. A sustainable and stable treatment system for IVDD is lacking because of the special organizational structure and low nutrient supply of AF. We here found that IVDD results in the impaired mitochondrial function of AF tissue, and mitochondrial autophagy (mitophagy) plays a protective role in this process. We therefore reported a thread-structural microneedle (T-MN) matching the ring structure of AF. Based on the adsorption effect of laminin, our T-MN could load with bone marrow mesenchymal stem cell-derived exosomes to envelope the regulating mitophagy microRNA (miRNA 378), named as T-MN@EXO@miR-378. In general, we offered in situ locking in the defect site of AF to prevent nucleus pulposus leakage and promoted AF repair. The design of the thread structure was aimed at bionically matching the layered AF structure, thereby providing stronger adhesion. The T-MN@EXO@miR-378 effectively attached to AF and slowly released therapeutic engineered exosomes, and prevented IVDD progression by restoring mitophagy, promoting AF cell proliferation and migration, and inhibiting the pathological remodeling of the extracellular matrix. This functional system can be used as an excellent tool for sustained drug release and has a certain prospect in substituting the conventional treatment of IVDD.

Interventional effect of core stability training on pain and muscle function of youth with chronic non-specific lower back pain: A randomized controlled trial

Nowadays, due to lifestyle changes, the number of young people suffering from chronic non-specific low back pain (CNLBP) is gradually increasing. The recent guidelines for the treatment of low back pain emphasize that exercise therapy is the preferred treatment method for CNLBP. This study take ordinary college male students with CNLBP as objective of the study, focused into how core stability training affected the pain and muscle function of the CNLBP of youth. Herein, 60 male subjects were randomly divided into a control group and an experimental group, and conducted a randomized control trial in the Sports Rehabilitation Laboratory of Guangxi Normal University from September to October 2023. The control group received traditional waist strength training, while the experimental group received core stability training. VAS scores, pain symptoms scores and clinical efficacy grades were evaluated. Waist muscles fitness was evaluated, including back muscle strength, the prone upper body up's static holding time, 1-min modified sit-ups' pcs, the supine abdominal curling's static holding time and the supine leg raising's static holding time. Waist movement function was also evaluated using oswestry disability index (ODI) questionnaire. Surface electromyographic (EMG) signals were collected from rectus abdominis, erector spinae and multifidus. The independent sample t-test was used to compare groups, and the paired sample t-test was used for the data comparison before and post-exercise within the group. The results of the study found that CNLBP was improved in both the experimental and control groups in the post-exercise. Compared to pre-exercise, there are significant decrease in the VAS scores (95%CI: 2.51 to 6.51, p = 0.000), pain symptoms scores (95%CI: 2.95 to 3.55, p = 0.000), waist movement function's evaluation scores for ODI (95%CI: 2.23 to 4.31, p = 0.000), rectus abdominis' IEMG values (95%CI: 2.29 to 4.39, p = 0.000), erector spinae and multifidus' IEMG values (95%CI: 2.18 to 4.45, p = 0.000) of experimental group in the post-exercise. Compared to pre-exercise, there are significant improvement in the back muscle strength (95%CI: 12.85 to 19.49, p = 0.000), the prone upper body up's static holding time (95%CI: 9.67 to 19.17, p = 0.000), the 1-min modified sit-ups' pcs (95%CI: 8.56 to 18.12, p = 0.000), the supine abdominal curling's static holding time (95%CI: 6.73 to 19.14, p = 0.000), and the supine leg raising's static holding time (95%CI: 8.21 to 18.35, p = 0.000) of experimental group in the post-exercise. In the post-exercise,there are significant lower in the VAS scores (95%CI: 1.41 to 4.98, p = 0.000), pain symptoms scores (95%CI: 1.14 to 1.79, p = 0.011), waist movement function's evaluation scores for ODI (95%CI: 1.13 to 2.25, p = 0.000), rectus abdominis' IEMG values (95%CI: 2.36 to 4.47, p = 0.000), erector spinae and multifidus' IEMG values (95%CI: 2.24 to 4.23, p = 0.017) of experimental group than those of control group. In the post-exercise, there are significant higher in the recovery rate (p = 0.000), the prone upper body up's static holding time (95%CI: 4.16 to 8.32, p = 0.008), and the supine abdominal curling's static holding time (95%CI: 3.89 to 7.44, p = 0.000) of experimental group than those of control group. Therefore, it can be concluded that core stability training is significantly effective in treating CNLBP in youth, enhancing lower back muscle function. This therapeutic effect is primarily attributed to the improvement in muscle function.

Chronic Low Back Pain: History, Symptoms, Pain Mechanisms, and Treatment

Chronic low back pain (cLBP) is the most frequently reported cause of years lived with disability. Identifying the anatomical structures or dysfunction contributing to patients' symptoms is critical to guiding treatment. The etiology of back pain and differential diagnosis is often broad, ranging from non-degenerative cLBP (trauma, tumor, inflammation, infection, etc.) to degenerative (also described as nonspecific) cLBP. After eliminating suspicion for more insidious causes of cLBP, a thorough investigation can be conducted in an attempt to identify a source of degenerative cLBP. Degenerative cLBP can originate from many sources, and a detailed understanding of the structures potentially involved is invaluable for an accurate diagnosis. This review article aims to provide a broad overview of the utility of clinical history, physical exam findings, imaging findings, and diagnostic procedures in identifying the cause of patients' cLBP. We provide a framework to help guide clinicians by dividing the structures into groups as follows: anterior vertebral column, posterior vertebral column, and extra-vertebral pain. For each condition listed, we touch on the treatment options that can be considered.

The association of lumbar intervertebral disc degeneration with low back pain is modified by underlying genetic propensity to pain

BACKGROUND CONTEXT

Associations between magnetic resonance imaging (MRI)-detected lumbar intervertebral disc degeneration (LDD) and LBP are often of modest magnitude. This association may be larger in specific patient subgroups.

PURPOSE

To examine whether the association between LDD and LBP is modified by underlying genetic predispositions to pain.

STUDY DESIGN

Cross-sectional study in UK Biobank (UKB) and Twins UK.

PATIENT SAMPLES

A genome-wide association study (GWAS) of the number of anatomical chronic pain locations was conducted in 347,538 UKB participants. The GWAS was used to develop a genome-wide polygenic risk score (PRS) in a holdout sample of 30,000 UKB participants. The PRS model was then used in analyses of 645 TwinsUK participants with standardized LDD MRI assessments.

OUTCOME MEASURES

Ever having had LBP associated with disability lasting ≥1 month (LBP1).

METHODS

Using the PRS as a proxy for "genetically-predicted propensity to pain", we stratified TwinsUK participants into PRS quartiles. A "basic" model examined the association between an LDD summary score (LSUM) and LBP1, adjusting for covariates. A "fully-adjusted" model also adjusted for PRS quartile and LSUM x PRS quartile interaction terms.

RESULTS

In the basic model, the odds ratio (OR) of LBP1 was 1.8 per standard deviation of LSUM (95% confidence interval [CI] 1.4-2.3). In the fully-adjusted model, there was a statistically significant LSUM-LBP1 association in quartile 4, the highest PRS quartile (OR=2.5 [95% CI 1.7-3.7], p=2.6×10-6), and in quartile 3 (OR=2.0, [95% CI 1.3-3.0]; p=.002), with small-magnitude and/or nonsignificant associations in the lowest 2 PRS quartiles. PRS quartile was a significant effect modifier of the LSUM-LBP1 association (interaction p≤.05).

CONCLUSIONS

Genetically-predicted propensity to pain modifies the LDD-LBP association, with the strongest association present in people with the highest genetic propensity to pain. Lumbar MRI findings may have stronger connections to LBP in specific subgroups of people.

3D Printed Pedicle Screws with Microarc Oxidation Ceramic Interfaces Enhance Osteointegration and Orthopedic Fixation Feasibility

Effective osteointegration is of great importance for pedicle screws in spinal fusion surgeries. However, the lack of osteoinductive activity of current screws diminishes their feasibility for osteointegration and fixation, making screw loosening a common complication worldwide. In this study, Ti-6Al-4V pedicle screws with full through-hole design were fabricated via selective laser melting (SLM) 3D printing and then deposited with porous oxide coatings by microarc oxidation (MAO). The porous surface morphology of the oxide coating and the release of bioactive ions could effectively support cell adhesion, migration, vascularization, and osteogenesis in vitro. Furthermore, an in vivo goat model demonstrated the efficacy of modified screws in improving bone maturation and osseointegration, thus providing a promising method for feasible orthopedic internal fixation.

The role of sirtuins in intervertebral disc degeneration: Mechanisms and therapeutic potential

Intervertebral disc degeneration (IDD) is one of the main causes of low back pain, which affects the patients' quality of life and health and imposes a significant socioeconomic burden. Despite great efforts made by researchers to understand the pathogenesis of IDD, effective strategies for preventing and treating this disease remain very limited. Sirtuins are a highly conserved family of (NAD+)-dependent deacetylases in mammals that are involved in a variety of metabolic processes in vivo. In recent years, sirtuins have attracted much attention owing to their regulatory roles in IDD on physiological activities such as inflammation, apoptosis, autophagy, aging, oxidative stress, and mitochondrial function. At the same time, many studies have explored the therapeutic effects of sirtuins-targeting activators or micro-RNA in IDD. This review summarizes the molecular pathways of sirtuins involved in IDD, and summarizes the therapeutic role of activators or micro-RNA targeting Sirtuins in IDD, as well as the current limitations and challenges, with a view to provide possible solutions for the treatment of IDD.

Disrupted Resting-State Functional Connectivity and Effective Connectivity of the Nucleus Accumbens in Chronic Low Back Pain: A Cross-Sectional Study

Purpose

Chronic low back pain (cLBP) is a recurring and intractable disease that is often accompanied by emotional and cognitive disorders such as depression and anxiety. The nucleus accumbens (NAc) plays an important role in mediating emotional and cognitive processes and analgesia. This study investigated the resting-state functional connectivity (rsFC) and effective connectivity (EC) of NAc and its subregions in cLBP.

Methods

Thirty-four cLBP patients and 34 age- and sex-matched healthy controls (HC) underwent resting-state functional magnetic resonance imaging (rs-fMRI). Seed-based rsFC and Dynamic Causal Modelling (DCM) were used to examine the alteration of the rsFC and EC of the NAc.

Results

Our results showed that the cLBP group had increased rsFC of the bilateral NAc-left superior frontal cortex (SFC), orbital frontal cortex (OFC), left angular gyrus, the left NAc-bilateral middle temporal gyrus, as well as decreased rsFC of left NAc-left supramarginal gyrus, right precentral gyrus, left cerebellum, brainstem (medulla oblongata), and right insula pathways compared with the HC; the results of the subregions were largely consistent with the whole NAc. In addition, the rsFC of the left NAc-left SFC was negatively correlated with Hamilton's Depression Scale (HAMD) scores (r = -0.402, p = 0.018), and the rsFC of left NAc-OFC was positively correlated with present pain intensity scores (r = 0.406, p = 0.017) in the cLBP group. DCM showed that the cLBP group showed significantly increased EC from the left cerebellum to the right NAc (p = 0.012) as compared with HC.

Conclusion

Overall, our findings demonstrate aberrant rsFC and EC between NAc and regions that are associated with emotional regulation and cognitive processing in individuals with cLBP, underscoring the pivotal roles of emotion and cognition in cLBP.

The Efficacy of the Smartphone App for the Self-Management of Low Back Pain: A Systematic Review and Assessment of Their Quality through the Mobile Application Rating Scale (MARS) in Italy

Smartphone apps for self-management are valuable tools to help manage low back pain (LBP) patients. The purposes of this systematic review were to (a) summarize the available studies on the efficacy of smartphone apps for self-management of LBP and (b) identify free applications available in Italy that offer strategies for LBP self-management and provide a qualitative assessment using the Mobile Application Rating Scale (MARS). According to the Prisma Checklist, six bibliographic databases were searched with the keywords 'low back pain', 'mobile application', 'smartphone', and 'telemedicine'. In total, 852 records were screened, and 16 were included in the systematic review. Of the six RCTs included, four reported a statistically significant decrease in pain in favor of the app group, and two RCTs did not. Only in a non-RCT was there an increase in the disability score. In the application research conducted on mobile stores, we identified and rated 25 applications through MARS. The overall scores ranged from 1.93 to 3.92 for the IOS app and 1.73 to 4.25 for the Play Store app. The findings suggest that few apps meet satisfying quality, content, and functionality criteria for LBP self-management.

Lumbar transforaminal epidural steroid injections with particulate vs. nonparticulate steroid: an evidence-informed review on shifting gear to a personalized medicine paradigm

PURPOSE OF REVIEW

To provide an evidence-informed review weighing the pros and cons of particulate vs. nonparticulate steroids for lumbar transforaminal epidural steroid injections (TFESI).

RECENT FINDINGS

The relative use of nonparticulate vs. particulate steroids for lumbar TFESI has risen recently in light of catastrophic consequences reported for the latter during cervical TFESI. Among various causes of spinal cord infarct, an exceedingly rare event in the lower lumbar spine, embolization of particulate steroid is among the least likely. Case reports have documented cases of spinal cord infarct during lower lumbar TFESI with both particulate and nonparticulate steroids, with database reviews finding no difference in complication rates. There is some evidence for superiority of particulate over nonparticulate steroids in well-designed studies, which could lead to increase steroid exposure (i.e. more injections) and treatment failure resulting in surgical and/or opioid management when nonparticulate steroids are utilized.

SUMMARY

Similar to a paradigm shift in medicine, a personalized approach based on a shared decision model and the consequences of treatment failure, should be utilized in deciding which steroid to utilize. Alternatives to ESI include high-volume injections with nonsteroid solutions, and the use of hypertonic saline, which possesses anti-inflammatory properties and has been shown to be superior to isotonic saline in preliminary clinical studies.