Comparison of lumbar muscle morphology in patients with chronic nonspecific low back pain with and without clinical lumbar segmental instability.

OBJECTIVES: Evaluation of spinal muscle morphology may be critical because of its impact on segmental stability and control of the lumbar spine in the subset of patients with clinical lumbar segmental instability (LSI). The purpose of this study was to compare lumbar muscle morphology in CNLBP patients with clinical LSI, CNLBP patients without clinical LSI. METHODS: This case-control study included 30 patients with CNLBP (15 with clinical LSI and 15 without clinical LSI) and 15 subjects without LBP. Axial magnetic resonance images from the L2 to S1 lumbar levels were used to evaluate the morphology of the lumbar muscles. RESULTS: A significant increase in the muscle-to-fat infiltration index and a significant decrease in the relative muscle cross-sectional area (rmCSA) of the multifidus muscle at the L3-L4 to L5-S1 levels were observed in both CNLBP groups compared to the control group (p<0.05). The mean erector spinae mean rmCSA was significantly greater in the clinical LSI group compared to the control group (SMD = 0.853, 95% CI = 0.105 to -1.6, P = 0.044) and also compared to the CNLBP without clinical LSI (SMD = 0.894, 95% CI = -1.645 to -0.144, P = 0.030) at the L4-L5 level. CONCLUSIONS: The atrophic changes of the multifidus muscle, in CNLBP patients with or without clinical LSI was observed. However, hypertrophic changes of the erector spinae muscle at the L4-L5 lumbar level were observed only in the clinical LSI group. Psaos major did not show significant atrophic or hypertrophic changes.

Paraspinal Muscle Changes in Individuals with and without Chronic Low Back Pain over a 4-Month Period: A Longitudinal MRI Study.

Background and Objectives: Previous research has shown associations between atrophy and fatty infiltration of the lumbar paraspinal musculature and low back pain (LBP). However, few studies have examined longitudinal changes in healthy controls and individuals with LBP without intervention. We aimed to investigate the natural variations in lumbar paraspinal musculature morphology and composition in this population over a 4-month period. Materials and Methods: Healthy controls and individuals with LBP were age- and sex-matched and completed several self-administered questionnaires. MRIs of L1-L5 were taken at baseline, 2 months, and 4 months to investigate cross-sectional area (CSA), along with DIXON fat and water images. A total of 29 participants had clear images for at least one level for all three time points. Means and standard deviations were calculated for the participant demographics. A two-way repeated measures ANOVA was performed to investigate CSA, fat signal fraction, and CSA asymmetry. Results: A total of 27 images at L3/L4, 28 images at L4/L5, and 15 images at L5/S1 were included in the final analysis. There were significant main effects of group for psoas CSA at the L3/L4 level (p = 0.02) and erector spinae (ES) CSA % asymmetry at the L3/L4 level (p < 0.001). There was a significant main effect of time for lumbar multifidus (LM) CSA % asymmetry at L4/L5 level (p = 0.03). Conclusions: This study provides insights into LM, ES, and psoas morphology in both healthy controls and affected individuals over a 4-month period without any intervention. Our findings suggest that psoas CSA at higher lumbar levels and CSA % asymmetry in general may be a better indicator of pathology and the development of pathology over time. Evaluating natural variations in paraspinal musculature over longer time frames may provide information on subtle changes in healthy controls and affected individuals and their potential role in chronic LBP.

Multifidus lesions: A possible pathological component in patients with low back pain after posterior lumbar surgery.

There are few histological studies on multifidus after lumbar surgery, and it is not clear whether multifidus changes affect the clinical outcome after lumbar surgery. The aim of this study was to investigate the relationship between multifidus changes and clinical outcomes after lumbar surgery. Patients underwent internal fixation removal after lumbar posterior surgery were enrolled. Patients were divided into a low back pain (LBP) group (n = 15) and a non-low back pain (non-LBP) group (n = 10).The Oswestry disability index (ODI) and visual analog scale (VAS) were completed. 18 patients with lumbar fracture surgery were included as the control group. Multifidus morphological changes were observed by hematoxylin and eosin and Masson staining. The expression of TGF-ß1 was observed by immunohistochemistry, immunofluorescence and Western blot. The cross-sectional area (CSA) of the multifidus in the non-LBP group and the control group were greater than those in the LBP group. TGF-ß1 expression and gray value ratio in the non-LBP group and the control group were lower than those in the LBP group. The multifidus CSA and TGF-ß1 expression in multifidus were strongly correlated with ODI and VAS. Patients with LBP after posterior lumbar surgery suffered from atrophy and fibrosis lesions in the multifidus, and the degree of multifidus lesions was closely related to dysfunction and pain, which might be one of the causes of LBP after posterior lumbar surgery.

A 42-year-old patient with renal cell carcinoma presenting as low back pain: A case report.

RATIONALE: Renal cell carcinoma (RCC) is the most common renal neoplasm, accounting for 2.4% of all cancers in Korea. Although the usual clinical manifestations of RCC include flank pain, hematuria, and palpable mass, RCC is generally characterized by a lack of early warning signs and is mostly discovered incidentally in advanced stage. This case report describes a 42-year-old Korean man diagnosed with giant RCC who presented with simple back pain. PATIENT CONCERNS: The clinical manifestation of a 42-year-old Korean man was chronic back pain. DIAGNOSES: Contrast-enhanced computed tomography showed a 19.1-cm sized heterogeneous enhancing mass on the right kidney and tumor thrombosis extending into inferior vena cava. INTERVENTION: Due to the large size of the tumor and extensive tumor thrombosis, the multidisciplinary team decided to administer neoadjuvant chemotherapy and an anticoagulant. Following 12 cycles of treatment with nivolumab and cabozantinib, he underwent a right radical nephrectomy with an adrenalectomy and tumor thrombectomy. OUTCOMES: Treatment was successful and posttreatment he started a cancer rehabilitation program. He was followed-up as an outpatient and no longer complains of back pain. LESSONS: RCC can manifest clinically as back pain, with diagnosis being difficult without appropriate imaging modalities. RCC should be included in the differential diagnosis of patients with low back pain, even at a young age.

A Proposed Treatment Algorithm for Low Back Pain Secondary to Bertolotti's Syndrome.

BACKGROUND: Chronic low back pain is widely prevalent, and there are a range of conditions that may result in the low back pain. In general, treatment of low back pain starts with conservative management such as medications, physical therapy, and home exercise regimens. If conservative measures fail, a range of interventional techniques can be employed to manage back pain. An uncommonly recognized cause of back pain is Bertolotti's syndrome which is a result of back pain due to lumbosacral transitional vertebrae (LSTV). LSTV is a congenital abnormality either characterized by the lumbarization of the sacrum where the first sacral bone fails to fuse with the rest of the sacrum or the sacralization of the lumbar spine where the L5 vertebra fuses with the sacrum creating a longer sacrum. In many cases, the condition can be recognized by imaging techniques such as an x-ray, computed tomography, or magnetic resonance imaging. OBJECTIVES: To propose a treatment algorithm for patients with low back pain secondary to Bertolotti's syndrome. STUDY DESIGN: Case study and treatment algorithm proposal. METHODS: A treatment algorithm for patients with low back pain secondary to Bertolotti's Syndrome which involves starting with local anesthetic and steroid injection of the pseudo-articulation, followed by radiofrequency ablation of the pseudo-articulation, and then complete endoscopic resection of the pseudo joint. RESULTS: The proposed stepwise treatment guideline has the ability to diagnose Bertolotti's syndrome as the cause of low back pain and provide symptomatic relief. LIMITATIONS: Several limitations exist for the study including the fact that the algorithmic approach may not fit every patient. Additionally, there would be benefit in future research studies comparing each step of the algorithm with conservative measures to compare efficacy and long-term outcomes of the procedures. CONCLUSIONS: Our stepwise approach to diagnosing and managing the pain resulting from Bertolotti's syndrome is an effective method of treatment for the condition.

Pediatrics severe low back pain by disc herniation: an uncommon entity.

BACKGROUND: Common severe back pain due to disc herniation is rare in the paediatric population which involves children under eighteen years of age. Paediatric lumbar disc herniation (LDH) cannot be considered the same disease as in adults, as it has potentially different natural and clinical backgrounds. The treatment of pediatric LDH is the other particularity of this condition. Indeed, in children, delaying surgery for a conservative treatment is justified. We report 3 cases treated in 8 years. CASE PRESENTATION: Three patients, two of whom were 14 years of age and one 17 years of age, were admitted for L5 or S1 lumbosciatica. A CT scan showed a lumbar disc herniation L5S1 associated with bi-isthmic lysis (and a transitional abnormality in 1 case or spina bifida occulta in 1 other case). The last patient had an magnetic resonance imaging (MRI) that showed a herniated L4L5 disc. The diagnosis of low back pain disc herniation was retained in two patients and that of disabling low back disc in one patient. Percutaneous discolysis in the two hyperalgesic cases and epidural corticosteroid infiltration in the disabling case were effective on lumbosciatica. CONCLUSION: Paediatric common lomw back pain caused by a disc herniation with a hyperalgic or disabling character posed a therapeutic problem which were solved by the invasive approaches that must be given priority nowadays with children.

Inter-software and inter-threshold reliability of quantitative paraspinal muscle segmentation.

PURPOSE: Changes in the cross-sectional area (CSA) and functional cross-sectional area (FCSA) of the lumbar multifidus (MF) and erector spinae muscles (ES) are factors that can contribute to low back pain. For the assessment of muscle CSA and composition there are various software and threshold methods used for tissue segmentation in quantitative analysis. However, there is currently no gold standard for software as well as muscle segmentation. This study aims to analyze the measurement error between different image processing software and different threshold methods for muscle segmentation. METHODS: Magnetic resonance images (MRI) of 60 patients were evaluated. Muscle CSA and FCSA measurements were acquired from axial T2-weighted MRI of the MF and ES at L4/L5 and L5/S1. CSA, FCSA, and FCSA/CSA ratio were measured independently by two observers. The MRI images were measured using two different software programs (ImageJ and Amira) and with two threshold methods (Circle/Overlap method) for each software to evaluate FCSA and FCSA/CSA ratio. RESULTS: Inter-software comparisons revealed high inter-rater reliability. However, poor inter-rater reliability were obtained with different threshold methods. CSA, FCSA, and FCSA/CSA showed excellent inter-software agreement of 0.75-0.99 regardless of the threshold segmentation method. The inter-rater reliability between the two observers ranged between 0.75 and 0.99. Comparison of the two segmentation methods revealed agreement between 0.19 and 0.84. FCSA and FCSA/CSA measured via the Overlap method were significantly higher than those measured via the Circle method (P < 0.01). CONCLUSION: The present study showed a high degree of reliability with very good agreement between the two software programs. However, study results based on different threshold methods should not be directly compared.

Relationship between lumbar spinal stenosis and axial muscle wasting.

BACKGROUND CONTEXT: Although the effect of lumbar spinal stenosis (LSS) on the lower extremities is well documented, limited research exists on the effect of spinal stenosis on the posterior paraspinal musculature (PPM). Similar to neurogenic claudication, moderate to severe spinal canal compression can also interfere with the innervation of the PPM, which may result in atrophy and increased fatty infiltration (FI). PURPOSE: This study aims to assess the association between LSS and atrophy of the PPM. STUDY DESIGN: Retrospective cross-sectional study. PATIENT SAMPLE: Patients undergoing MRI scans at a tertiary orthopedic center for low back pain or as part of a preoperative evaluation. OUTCOME MEASURES: The functional cross-sectional area (fCSA) and percent fatty infiltration (FI) of the PPM at L4. METHODS: Lumbar MRIs of patients at a tertiary orthopedic center indicated due to lower back pain (LBP) or as a presurgical workup were analyzed. Patients with previous spinal fusion surgery or scoliosis were excluded. LSS was assessed according to the Schizas classification at all lumbar levels. The cross-sectional area of the PPM was measured on a T2-weighted MRI sequence at the upper endplate of L4. The fCSA and fatty infiltration (FI) were calculated using custom software. Crude differences in FI and fCSA between patients with no stenosis and at least mild stenosis were tested with the Wilcoxon signed-rank test. To account for possible confounders, a multivariable linear regression model was used to adjust for age, sex, body mass index (BMI), and disc degeneration. A subgroup analysis according to MRI indication was performed. RESULTS: A total of 522 (55.7% female) patients were included. The median age was 61 years (IQR: 51-71). The greatest degree of moderate and severe stenosis was found at L4/5, 15.7%, and 9.2%, respectively. Stenosis was the least severe at L5/S1 and was found to be 2% for moderate and 0.2% for severe stenosis. The Wilcoxon test showed significantly increased FI of the PPM with stenosis at any lumbar level (p<.001), although no significant decrease in fCSA was observed. The multivariable regression model showed a significant increase in FI with increased LSS at L1/2, L2/3, and L3/4 (p=.013, p<.01 and p=.003). The severity of LSS at L4/5 showed a positive association with the fCSA (p=.019). The subgroup analysis showed, the effect of LSS was more pronounced in nonsurgical patients than in patients undergoing surgery. CONCLUSIONS: In this study, we demonstrated a significant and independent association between LSS and the composition of the PPM, which was dependent on the level of LSS relative to the PPM. In addition to neurogenic claudication, patients with LSS might be especially susceptible to axial muscle wasting, which could worsen LSS due to increased spinal instability, leading to a positive feedback loop.

Comprehensive Grading System of Inflammatory Features of the Lumbar Facet Joints on Magnetic Resonance Imaging.

STUDY DESIGN: Retrospective. OBJECTIVE: We aimed to describe a magnetic resonance imaging (MRI)-based grading system of inflammatory features of the lumbar facet joints using an atlas and assess its reliability. SUMMARY OF BACKGROUND DATA: Chronic low back pain is often caused by facet joint arthropathy. Inflammatory features are often evident on MRI. While several grading systems of facet arthropathy have been described, there is scant data on the reliability of these systems, and none focus exclusively on inflammatory features. MATERIALS AND METHODS: We describe a grading system that assesses facet joint effusion, bone marrow edema, and soft tissue edema. Each feature was graded from 0 to 3 (facet edema) or 0 to 2 (bone marrow edema intensity and extent, soft tissue edema intensity and extent). Four spine experts graded MRIs of 50 subjects at the bilateral L3/4, L4/5, and L5/S1 levels. All subjects had symptomatic facet arthropathy and received therapeutic facet joint injections. We assessed the intra-reader and inter-reader reliability of each feature at each joint and summarized across all six joints. RESULTS: The mean age of subjects was 56 years (SD = 17), and 48% were female. The injections occurred at the L3/4 level in 12% of cases, at L4/5 in 88%, and at L5/S1 in 80% of cases. The intra-reader reliability kappa's for each feature ranged from 0.42 to 0.81. In contrast, the inter-reader reliability kappa values for each feature ranged from 0.37 to 0.54. CONCLUSION: MRI inflammatory features of the lumbar facet joints are often noted in patients with low back pain. The proposed grading system is reliable and could serve as a research tool for studies assessing the clinical relevance and prognostic value of these features.

PILLAR: ParaspInaL muscLe segmentAtion pRoject - a comprehensive online resource to guide manual segmentation of paraspinal muscles from magnetic resonance imaging.

BACKGROUND: There is an increasing interest in assessing paraspinal morphology and composition in relation to low back pain (LBP). However, variations in methods and segmentation protocols contribute to the inconsistent findings in the literature. We present an on-line resource, the ParaspInaL muscLe segmentAtion pRoject (PILLAR, https://projectpillar.github.io/ ), to provide a detailed description and visual guide of a segmentation protocol by using the publicly available ITK-SNAP software and discuss related challenges when performing paraspinal lumbar muscles segmentations from magnetic resonance imaging (MRI). METHODS: T2-weighted and corresponding fat-water IDEAL axial MRI from 3 males and 3 females (2 chronic LBP and 1 control for each sex) were used to demonstrate our segmentation protocol for each lumbar paraspinal muscle (erector spinae, lumbar multifidus, quadratus lumborum and psoas) and lumbar spinal level (L1-L5). RESULTS: Proper segmentation requires an understanding of the anatomy of paraspinal lumbar muscles and the variations in paraspinal muscle morphology and composition due to age, sex, and the presence of LBP or related spinal pathologies. Other challenges in segmentation includes the presence and variations of intramuscular and epimuscular fat, and side-to-side asymmetry. CONCLUSION: The growing interest to assess the lumbar musculature and its role in the development and recurrence of LBP prompted the need for comprehensive and easy-to-follow resources, such as the PILLAR project to reduce inconsistencies in segmentation protocols. Standardizing manual muscle measurements from MRI will facilitate comparisons between studies while the field is progressively moving towards the automatization of paraspinal muscle measurements for large cohort studies.

Effect of Radiofrequency on Dorsal Root Ganglion Versus Transforaminal Steroids Injection on Tumor Necrosis Factor-Alpha Level in Lumbar Radicular Pain.

BACKGROUND: The mechanism of pain control with pulsed radiofrequency (PRF) is unclear. OBJECTIVES: We aimed to compare the efficacy of combined PRF on dorsal root ganglion (DRG) with transforaminal epidural steroid injection (TFESI) vs TFESI-alone on pain improvement and serum tumor necrosis factor-alpha (TNF-a) level in lumbar disc-related radicular pain. STUDY DESIGN: Prospective, randomized, controlled trial. SETTING: Neurology and Pain Management clinics. METHODS: A total of 80 patients with lumbar disc prolapse were divided into 2 groups: combined PRF on DRG with TFESI group and TFESI-alone group. The Numeric Rating Scale (NRS-11), Oswestry Disability Index (ODI), and Functional Rating Index (FRI) before intervention and at 2 weeks, 1 month, and 3 months after the intervention were observed. Serum TNF-a level was assessed pre- and post-intervention at 3 months. RESULTS: The scores of NRS-11, ODI, and FRI showed a significant improvement at 2 weeks, 1 month, and 3 months following intervention in both combined PRF & TFESI group and TFESI-alone group (P < 0.001 in all comparisons), with no significant difference between the 2 groups. Serum TNF-a levels showed a statistically significant reduction, 3 months following intervention in the combined PRF & TFESI group (P < 0.001), but not in the TFESI-alone group (P = 0.297) (P between groups < 0.001). LIMITATIONS: The main limitation of this study is that TNF-a level was not assessed earlier to see how long the steroids might reduce TNF-a. On the other hand, further study with extended follow-up periods is needed to confirm the long-term lowering effect of TNF-a provided by PRF. CONCLUSIONS: Combined PRF on DRG with TFESI showed similar outcomes to TFESI-alone in relieving pain in patients with lumbar disc prolapse. However, PRF on DRG caused a significant decrease in TNF-a serum levels at 3 months.

Induction of Lumbar Disc Degeneration in Rabbits Through a Transabdominal Approach.

Lower back pain is an extremely common medical issue in populations worldwide. One of the main contributors to lower back pain is intervertebral disc (IVD) degeneration. An ideal animal model of IVD degeneration is essential to study the pathophysiology of lower back pain and investigate potential therapeutic strategies. Rabbit models are reliable, economical, and easily established animal models. The retroperitoneal approach has been widely used to induce IVD degeneration in rabbit models. However, there are reported complications associated with this technique, such as the avulsion of segmental arteries and nerve root injury. In this paper, we aim to show a surgical protocol using needle puncture to establish rabbit lumbar disc degeneration via a transabdominal approach. Consequently, radiological checks and histological analyses indicated that lumbar disc degeneration was successfully established in rabbits. This surgical protocol presents the precise location of target discs and high reproducibility of IVD degeneration models with fewer complications.

Modic change is associated with increased BMI but not autoimmune diseases in TwinsUK.

PURPOSE: Low back pain (LBP) is one of the largest causes of morbidity worldwide. The aetiology of LBP is complex, and many factors contribute to the onset. Bone marrow lesions within the vertebra adjacent to an intervertebral degenerate disc named Modic change (MC) have been suggested as a diagnostic subgroup of LBP. Autoimmune response has been proposed to be one of the causes that promote the development of MC. The aim of the current investigation is to assess prevalence and severity of MC and LBP in participants with an autoimmune disease diagnosis in a well-documented cohort of adult twin volunteers. METHODS: Multivariate generalized mixed linear models (GLMM) were implemented in order to calculate the association between having an autoimmune disorder and MC prevalence, width and severe and disabling LBP. The model was corrected for family structure as well as for covariates such as age, BMI and smoking. RESULTS: No association was found between diagnosis of autoimmune disorder and MC. Interestingly, BMI was independently associated with MC width but not to MC prevalence. These results help to shed light on the relationship between MC and autoimmunity as well as the role of BMI in the development of the lesions. CONCLUSION: This study is the first to examine autoimmune disorders and MC prevalence in a large, population-based female cohort. The study was well powered to detect a small effect. No association was found between having a diagnosis of one or more autoimmune conditions and MC prevalence, width or LBP.

An Effectiveness Evaluation of Nucleo-Annuloplasty for Lumbar Discogenic Lesions Using Disc-FX: A Scoping Review.

Background and Objectives: Degenerative disk disease is a widespread chronic condition that causes diskogenic pain. Diskogenic pain can be treated with various therapy methods. Disc-FX is a revolutionary, minimally invasive, percutaneous nucleo-annuloplasty method that combines manual diskectomy with nuclear and annular remodeling using radiofrequency ablation to relieve diskogenic pain. In this study, the technical features, clinical outcomes, and complications of Disc-FX are summarized. Materials and Methods: A comprehensive literature review was performed. By exploring several databases, we collected studies on Disc-FX for treating diskogenic pain. The outcomes included perioperative data, clinical results, and complications. Results: In the 15 studies included, data from 570 patients were collected. L4-L5 was the most frequently operated level, and most cases underwent single-level procedures. The follow-up period for these patients ranged from 2 months to 24 months. One study reported a procedure time between 35 and 60 min, whereas the remaining studies reported a procedure time of less than 30 min. The mean visual analog scale score decreased from 7.22 preoperatively to 1.81 at the final follow-up. The mean numerical rating scale score decreased from 6.98 preoperatively to 3.9 at the final follow-up. The mean Japanese Orthopaedic Association score improved from 16.26 preoperatively to 25.88 in the final follow-up. The mean Oswestry Disability Index score decreased from 35.37 preoperatively to 14.66 at the final follow-up. The mean satisfaction rate (based on the Macnab criteria) was 87.6% (range, 78.4-95.2%). The total incidence of postoperative transient pain was 8.77% (50/570) after nucleo-annuloplasty using Disc-FX, and recurrence was 1.58% (9/570). Conclusions: According to our comprehensive evaluation, using percutaneous nucleo-annuloplasty for treating lumbar diskogenic diseases provided considerable pain alleviation and improved functional outcomes with fewer complications. Disc-FX is a safe and effective procedure that is a good treatment option for patients with diskogenic pain.

Circ-STC2 promotes the ferroptosis of nucleus pulposus cells via targeting miR-486-3p/TFR2 axis.

BACKGROUND: Low back pain (LBP) has become the second leading cause of disability worldwide, which has brought great economic burden to people. It is generally believed that intervertebral disc degeneration (IDD) is the main cause of LBP. This study aimed to explore the role of circ-STC2 in the pathogenesis of IDD. METHODS: Nucleus pulposus cells (NPCs) were treated with T-Butyl Hydrogen Peroxide (TBHP) to establish IDD model in vitro. RT-qPCR was performed to detect mRNA expressions. The cell viability was detected with CCK-8 assay. The levels of lactate dehydrogenase (LDH), malondialdehyde (MDA), Fe2+ and glutathione (GSH) of NPCs were measured by corresponding kits. The protein expressions were determined by western blot. Dual-luciferase reporter and RNA pull-down assays were conducted to verify the relationship between circ-STC2 or transferrin recepto 2 (TFR2) and miR-486-3p. RESULTS: Circ-STC2 and TFR2 expressions were up-regulated in IDD tissues, and miR-486-3p expression was down-regulated. Knockdown of circ-STC2 promoted the cell viability and inhibited the ferroptosis of the NPCs. The GSH levels, and glutathione peroxidase 4 (GPX4) and solute carrier family 7 member 11 (SLC7A11) protein expressions were increased, the LDH, MDA and Fe2+ levels and achaete-scute complexlike 4 (ASCL4) protein expressions were decreased after circ-STC2 knockdown. Knockdown of miR-486-3p abrogated the si-circ-STC2 effects and overexpression of TFR2 reversed the miR-486-3p mimic effects. CONCLUSIONS: Circ-STC2 inhibits the cell viability, induced the ferroptosis of the TBHP treated NPCs via targeting miR-486-3p/TFR2 axis.

Lumbar Extensor and Flexor Muscle Structural Changes in Young Female Nurses with Chronic Bilateral Non-Specific Low Back Pain: A Case-Control Study.

BACKGROUND: Muscle structural studies on non-specific low back pain in young female nurses are rare. This study aimed to investigate the changes of lumbar extensor and flexor muscle cross-sectional area and fatty infiltration in young female nurses with chronic bilateral non-specific low back pain by lumbar spine magnetic resonance imaging to speculate on the possible pathogenesis. METHODS: The magnetic resonance imaging (MRI) data of 58 female nurses with chronic bilateral non-specific low back pain and 60 healthy female controls were analyzed retrospectively. The lumbar extensor and flexor muscle cross-sectional area/intervertebral disc cross-sectional area ratio, as well as magnetic resonance imaging signal intensity of lumbar extensor (erector spinae; multifidus) and flexor muscles (psoas muscle) were measured, calculated and compared between nurses and healthy controls by independent samples t-test. In addition, each mean MRI signal intensity of lumbar extensor or flexor muscles in nurses at different anatomical segments from lumbar vertebrae 2 (L2)-L3 to L5-sacral vertebrae 1 (S1) was also compared, and one-way Analysis of Variance (ANOVA) analyzed the mean MRI signal intensity between muscles in nurses with multiple comparisons. RESULTS: There was no significant difference in lumbar extensor and flexor muscle cross-sectional area/intervertebral disc cross-sectional area ratio between nurses with chronic bilateral non-specific low back pain and healthy controls, p > 0.01. The magnetic resonance imaging signal intensity in lumbar extensor and flexor muscle was significantly higher in nurses with chronic bilateral non-specific low back pain than in healthy controls, p < 0.01. The MRI signal intensity of lumbar extensor muscle at the lower lumbar segments was higher than at the upper ones. The magnetic resonance imaging signal intensity of the extensor muscle (erector spinae; multifidus) was significantly higher than that of the flexor muscle (psoas muscle), p < 0.01. CONCLUSIONS: This study showed that young nurses with chronic bilateral non-specific low back pain have lumbar extensor and flexor muscle fatty infiltration without muscle atrophy. We hypothesized that muscle fatty infiltration may occur prior to muscle atrophy. Therefore, the high fatty infiltration of the lumbar extensor and flexor muscle may be a cause or a result of chronic bilateral non-specific low back pain in young nurses.

Why Are Some Intervertebral Discs More Prone to Degeneration?: Insights Into Isolated Thoracic "Dysgeneration".

STUDY DESIGN: Prospective observational study. OBJECTIVE: To determine the prevalence of isolated thoracic degeneration on magnetic resonance imaging (MRI), demographic factors and imaging features, as well as the patient-reported quality of life outcomes associated with this condition. SUMMARY OF BACKGROUND DATA: Thoracic intervertebral discs are least susceptible to disc degeneration (DD) and may represent a manifestation of "dysgeneration." These discs may never be hydrated from the beginning and seem hypointense on MRI. PATIENTS AND METHODS: A population-based MRI study of 2007 volunteers was conducted. Each disc from C2/3 to L5/S1 was measured by Pfirrmann and Schneiderman grading. Disc herniation, Schmorl node (SN), high-intensity zones (HIZ), and Modic changes were studied. DD was defined by Pfirrmann 4 or 5. patient-reported quality of life scores, including a 36-item short-form questionnaire and visual analog scale for low back pain, were recorded. Subjects were divided into "isolated thoracic degeneration" (only thoracic segment) and "tandem thoracic degeneration" (thoracic with other segments). The association between imaging findings and isolated thoracic degeneration was determined using multivariate logistic regression. RESULTS: The mean age of the subjects was 50.0 ± 0.5 and 61.4% were females (n = 1232). Isolated thoracic degeneration was identified in 2.3% of the cohort. Factors associated with isolated thoracic degeneration included lower age, C6/7 HIZ, T8/9 HIZ, and T8/9 SN. Factors associated with tandem thoracic degeneration included L4/5 posterior bulging. The thoracic and lumbar tandem degeneration group demonstrated higher bodily pain, despite a lower visual analog scale, and a higher physical component score of the 36-item short form. CONCLUSIONS: Isolated thoracic degeneration demonstrated an earlier age of onset, mostly involving the mid-thoracic region (T5/6-T8/9), and in association with findings such as SN. Subjects with tandem thoracolumbar degeneration had less severe lumbar DD and low back pain as compared with those with isolated lumbar degeneration. This paints the picture of "dysgeneration" occurring in the thoracic and lumbar spine. LEVEL OF EVIDENCE: 1.

Emerging tissue engineering strategies for annulus fibrosus therapy.

Low back pain is a major public health concern experienced by 80% of the world's population during their lifetime, which is closely associated with intervertebral disc (IVD) herniation. IVD herniation manifests as the nucleus pulposus (NP) protruding beyond the boundaries of the intervertebral disc due to disruption of the annulus fibrosus (AF). With a deepening understanding of the importance of the AF structure in the pathogenesis of intervertebral disc degeneration, numerous advanced therapeutic strategies for AF based on tissue engineering, cellular regeneration, and gene therapy have emerged. However, there is still no consensus concerning the optimal approach for AF regeneration. In this review, we summarized strategies in the field of AF repair and highlighted ideal cell types and pro-differentiation targeting approaches for AF repair, and discussed the prospects and difficulties of implant systems combining cells and biomaterials to guide future research directions. STATEMENT OF SIGNIFICANCE: Low back pain is a major public health concern experienced by 80% of the world's population during their lifetime, which is closely associated with intervertebral disc (IVD) herniation. However, there is still no consensus concerning the optimal approach for annulus fibrosus (AF) regeneration. In this review, we summarized strategies in the field of AF repair and highlighted ideal cell types and pro-differentiation targeting approaches for AF repair, and discussed the prospects and difficulties of implant systems combining cells and biomaterials to guide future research directions.

Altered habenular connectivity in chronic low back pain: An fMRI and machine learning study.

The habenula has been implicated in the pathogenesis of pain and analgesia, while evidence concerning its function in chronic low back pain (cLBP) is sparse. This study aims to investigate the resting-state functional connectivity (rsFC) and effective connectivity of the habenula in 52 patients with cLBP and 52 healthy controls (HCs) and assess the feasibility of distinguishing cLBP from HCs based on connectivity by machine learning methods. Our results indicated significantly enhanced rsFC of the habenula-left superior frontal cortex (SFC), habenula-right thalamus, and habenula-bilateral insular pathways as well as decreased rsFC of the habenula-pons pathway in cLBP patients compared to HCs. Dynamic causal modelling revealed significantly enhanced effective connectivity from the right thalamus to right habenula in cLBP patients compared with HCs. RsFC of the habenula-SFC was positively correlated with pain intensities and Hamilton Depression scores in the cLBP group. RsFC of the habenula-right insula was negatively correlated with pain duration in the cLBP group. Additionally, the combination of the rsFC of the habenula-SFC, habenula-thalamus, and habenula-pons pathways could reliably distinguish cLBP patients from HCs with an accuracy of 75.9% by support vector machine, which was validated in an independent cohort (N = 68, accuracy = 68.8%, p = .001). Linear regression and random forest could also distinguish cLBP and HCs in the independent cohort (accuracy = 73.9 and 55.9%, respectively). Overall, these findings provide evidence that cLBP may be associated with abnormal rsFC and effective connectivity of the habenula, and highlight the promise of machine learning in chronic pain discrimination.

Application of critical pathway of integrative medical service for lumbar herniated nucleus pulposus: A protocol for single-centered prospective observational study.

BACKGROUND: Lumbar herniated nucleus pulposus (L-HNP) is a condition in which fibroblasts escape due to degenerative changes or external forces in the intervertebral disc, causing neurological symptoms by compressing the dura mater or nerve root. OBJECTIVES: The purpose of this study is to analyze and compare the effectiveness, economic feasibility, and safety of using an integrated medical service critical pathway (CP) in L-HNP patients. METHODS: This single-center prospective observational study will be performed at Kyung Hee University Medicine Hospital and Kyung Hee University Korean Medicine Hospital. The inclusion criteria are a diagnosis of L-HNP on magnetic resonance imaging or computed tomography scans, age under 80 years, a visual analog scale score of 7 or higher for either lower back pain or lower extremity pain. The included 102 participants will be classified into 6 groups (n = 17 in each group): CP application with conservative treatment; CP application with open discectomy; CP application with intrabody fusion; conservative treatment without CP application; open discectomy without CP application; and interbody fusion without CP application. We will collect data on the visual analog scale, ODI, SF-36, and EQ-5D-3L scores; number of admission days; medical staff satisfaction; patients health service satisfaction; waiting time for consultations; use of pain relievers; and CP application and completion rates. CONCLUSION: In future, this study is expected to serve as a basis for follow-up studies on the development and application of CPs in integrated medical services for various diseases, including lumbar herniated nucleus pulposus.