Management of symptomatic lumbar degenerative disk disease

Orthobiologic Management Options for Degenerative Disc Disease

Degenerative disc disease (DDD) is a pervasive condition that limits quality of life and burdens economies worldwide. Conventional pharmacological treatments primarily aimed at slowing the progression of degeneration have demonstrated limited long-term efficacy and often do not address the underlying causes of the disease. On the other hand, orthobiologics are regenerative agents derived from the patient's own tissue and represent a promising emerging therapy for degenerative disc disease. This review comprehensively outlines the pathophysiology of DDD, highlighting the inadequacies of existing pharmacological therapies and detailing the potential of orthobiologic approaches. It explores advanced tools such as platelet-rich plasma and mesenchymal stem cells, providing a historical overview of their development within regenerative medicine, from foundational in vitro studies to preclinical animal models. Moreover, the manuscript delves into clinical trials that assess the effectiveness of these therapies in managing DDD. While the current clinical evidence is promising, it remains insufficient for routine clinical adoption due to limitations in study designs. The review emphasizes the need for further research to optimize these therapies for consistent and effective clinical outcomes, potentially revolutionizing the management of DDD and offering renewed hope for patients.

A Decreasing National Trend in Lumbar Disc Arthroplasty

STUDY DESIGN

Retrospective National Database Study.

OBJECTIVES

The aim of this study was to investigate the national trend of lumbar disc arthroplasty (LDA) utilization from 2005 to 2017.

METHODS

Patients undergoing primary LDA between 2005 and 2017 were identified in the National Inpatient Sample (NIS) database. Year of the procedure, demographic, socioeconomic, hospital, and cost parameters were analyzed. The data was weighted using provided weights from the NIS database to generate national estimates of LDA procedure incidence. Lastly, we assessed the incidence of cervical disc arthroplasty (CDA) between 2005 and 2017 to serve as a historical comparison.

RESULTS

An estimated 20 460 patients underwent primary LDA in the United States between 2005 and 2017. There was an initial decrease in LDA procedures between 2005 and 2006 and then a plateau between 2006 and 2009. From 2010 to 2013, there was a significant year-over-year decrease in annual LDA procedures performed, followed by a second plateau from 2014 to 2017. Overall, LDA procedures decreased 82% from 2005 to 2017. Over the same time, the annual incidence of CDA utilization increased 795% from approximately 474 procedures in 2005 to 4245 procedures in 2017 (P < .01).

CONCLUSIONS

Lumbar disc arthroplasty utilization decreased 82% from 2005 to 2017, with a significant decrease in the rate of utilization noted after 2010. The utilization of LDA to treat selected degenerative lumbar conditions has not paralleled the increasing popularity of CDA, and, in fact, has demonstrated a nearly opposite utilization trend.

Rates, Predictive Factors, and Adverse Outcomes of Fusion Surgery for Lumbar Degenerative Disorders in Ontario, Canada, Between 2006 and 2015: A Retrospective Cohort Study

BACKGROUND

The addition of fusion surgery to the decompression for lumbar degenerative disorders remains controversial. The purpose of this study is to compare the rate and outcome of decompression and fusion versus decompression alone.

METHODS

This population-based retrospective cohort study used several linked administrative databases to identify patients who underwent spinal decompression surgery in Ontario, Canada, from 2006 to 2015. Patients who had previous spine surgery, concurrent lumbar disc replacement, or a diagnosis other than degenerative disc disease were excluded. Adjusted logistic regression was used to assess our outcomes.

RESULTS

We identified 33,912 patients, of whom 9748 (28.74%) underwent fusion. Overall, fusion rates increased from 27.66% to 31.33% over the study period (P = 0.025). Factors associated with fusion included: older age, female sex, American Society of Anesthesiologists score ≥3, previous total joint replacement, and surgery by an orthopedic surgeon. Fusion surgery was associated with increased odds of 30-day mortality (odds ratio [OR] 1.77, 95% confidence interval [CI] 1.01-3.09; P = 0.046), 30-day (OR 1.94, 95% CI 1.53-2.46; P < 0.0001) and 90-day reoperation (OR 1.66, 95% CI 1.35-2.05; P < 0.0001), and 30-day readmission (OR 1.23, 95% CI 1.02-1.49; P = 0.027) when adjusting for confounding variables. The odds of suffering a complication after fusion and decompression surgery vs. decompression surgery alone were 4.3-fold greater (95% CI 3.78-5.09; P < 0.0001).

CONCLUSIONS

As compared with decompression alone, spinal fusion for degenerative lumbar disorders is associated with increased odds of adverse outcomes. These findings highlight the need for spine surgeons to consider carefully their indications for fusion procedures in the setting of degenerative spinal disorders.

Correlation between motor behavior and age-related intervertebral disc degeneration in cynomolgus monkeys

Background

The motor behavior in patients with lumbar intervertebral disc degeneration (IDD) and animal models should be changed due to pain. However, there does not seem to be a strong correlation between IDD and motor behavior. Therefore, it is necessary to understand the correlation between motor behavior and age-related IDD.

Methods

Twenty-one healthy male cynomolgus monkeys (Macaca fascicularis) distributed across the age range were included in this study. The experimental animals were divided into two groups: caged group (n = 14) and free-range group (n = 7). The data of IDD and motor behavior were obtained through magnetic resonance imaging (MRI) and PrimateScan Automatic Behavior Analysis System. More than 20 basic motor behaviors could be recorded and quantified, and then reclassified into 9 combined categories. We defined the sum of the duration of activity-related combined categories as the total duration of activity in 3 hours. The activity zone of the cynomolgus monkeys in the cage could be divided into top and bottom zones. Analyze the correlation between motor behavior and IDD.

Results

Age was correlated with both Pfirrmann grades (r = .700; P < .001) and T2 values (r = -.369; P < .001). The T2 value in the caged group was 45.97 ± 8.35 ms, which was significantly lower than the 55.90 ± 8.73 ms in the free-range group (P < .001). The mean T2 values were positively correlated with hanging duration (r = .548, P < .05), the total duration of activity (r = .496, P < .05), and top zone duration (r = .541, P < .05).

Conclusions

There is an interactional relationship between IDD and motor behavior. Motor behavior could be used as one of the diagnostic indicators of IDD. It could also be used to infer the presence or extent of IDD in animal models. Avoiding a sedentary lifestyle and engaging in exercise in daily life could alleviate IDD.

Intradiscal vacuum phenomenon and spinal degeneration: a cross-sectional analysis of 219 subjects

INTRODUCTION

Intradiscal vacuum phenomenon (IVP) is the collection of gas within the intervertebral discs. It has been reported with various spinal disorders. The exact role of IVP in spinal degeneration leading to low back pain (LBP) is unclear. We aimed to obtain the prevalence of IVP in patients with LBP. Our second aim was to understand whether IVP was associated with intervertebral disc degeneration (IVDD), Modic changes, and subchondral sclerosis (SS).

METHODS

A total of 12.450 consecutive patients with chronic LBP were evaluated in terms of having abdominal computed tomography (CT) scan concomitant with lumbar spine magnetic resonance imaging (MRI) using radiological database of three spine centers. We excluded the patients with a history of malignancy, metabolic disease, spinal infection, traumatic or osteoporotic spine fracture, and spine surgery. All lumbar levels were evaluated in terms of IVDD and Modic changes on MRI, while they were evaluated in terms of IVP and SS on CT scans.

RESULTS

We included 219 patients. Severe IVDD, Modic changes, IVP, and SS were seen in 53.9% (n: 118), 38.8% (n: 85), 26.5% (n: 58), and 16% (n: 35) of the patients, respectively. Intradiscal vacuum phenomenon was closely associated with severe IVDD (OR: 8.204), Modic changes (OR: 3.547) and SS (OR: 4.231).

DISCUSSION

Intradiscal vacuum phenomenon was closely associated with severe IVDD, Modic changes, and SS. Further prospective clinical and laboratory studies are necessary to better delineate the pathogenesis of IVP.

Increased serum CXCL10 levels are associated with clinical severity and radiographic progression in patients with lumbar disc degeneration

BACKGROUND

Lumbar intervertebral degenerative disc disease (IDD) is a multifaceted progressive condition that commonly occurs in conjunction with lumbar disc herniation (LDH). CXCL10 mRNA appears to be increased in both IDD and LHD.

OBJECTIVE

This study was performed to identify the relationship between serum CXCL10 levels and disease severity in patients with IDD.

METHODS

136 IDD patients with low back pain, 127 asymptomatic volunteers and 120 healthy controls were enrolled. Serum CXCL10 protein concentrations were detected using commercial human CXCL10 ELISA Kits. Serum CXCL10 mRNA were examined using qRT-PCR. Clinical severity was assessed using the visual analog scale (VAS) and Oswestry Disability Index(ODI) scores. Radiographic severity was defined using the MRI-based Pfirrmann classification of disc degeneration. Receiver operating characteristic (ROC) curve analysis was used in estimating the correlation between CXCL10 and Pfirrmann grade. The cross-sectional area (CSA) of the lumbar multifidus muscle (LMM) and psoas major (PM) were calculated, and fat infiltration was evaluated by Ropponen-Kjaer criteria.

RESULTS

Serum CXCL10 concentrations were markedly raised in IDD patients with low back pain in contrast to asymptomatic individuals and healthy controls. Serum CXCL10 levels were positively associated with Pfirrmann grade. ROC curve analysis indicated that serum CXCL10 correlated well with Pfirrmann grade. In addition, serum CXCL10 concentrations were significantly higher in IDD patients with LMM and PM degeneration compared with IDD patients without degeneration. Increased CXCL10 levels positively correlated with VAS and ODI scores, as well as decreased CSA and fat filtration of the LMM and PM.

CONCLUSION

Increased serum CXCL10 levels correspond to clinical severity and radiographic progression in IDD patients.

Quercetin Suppresses Apoptosis and Attenuates Intervertebral Disc Degeneration via the SIRT1-Autophagy Pathway

Intervertebral disc degeneration (IDD) has been generally accepted as the major cause of low back pain (LBP), which causes an enormous socioeconomic burden. Previous studies demonstrated that the apoptosis of nucleus pulposus (NP) cells and the dyshomeostasis of extracellular matrix (ECM) contributed to the pathogenesis of IDD, and effective therapies were still lacking. Quercetin, a natural flavonoid possessing a specific effect of autophagy stimulation and SIRT1 activation, showed some protective effect on a series of degenerative diseases. Based on previous studies, we hypothesized that quercetin might have therapeutic effects on IDD by inhibiting the apoptosis of NP cells and dyshomeostasis of ECM via the SIRT1-autophagy pathway. In this study, we revealed that quercetin treatment inhibited the apoptosis of NP cells and ECM degeneration induced by oxidative stress. We also found that quercetin promoted the expression of SIRT1 and autophagy in NP cells in a dose-dependent manner. Autophagy inhibitor 3-methyladenine (3-MA) reversed the protective effect of quercetin on apoptosis and ECM degeneration. Moreover, SIRT1 enzymatic activity inhibitor EX-527, suppressed quercetin-induced autophagy and the protective effect on NP cells, indicating that quercetin protected NP cells against apoptosis and prevented ECM degeneration via SIRT1-autophagy pathway. In vivo, quercetin was also demonstrated to alleviate the progression of IDD in rats. Taken together, our results suggest that quercetin prevents IDD by promoting SIRT1-dependent autophagy, indicating one novel and effective therapeutic method for IDD.

Lumbar intervertebral disc mRNA sequencing identifies the regulatory pathway in patients with disc herniation and spondylolisthesis

Lumbar degenerative disc disease (DDD) is a multifaceted progressive condition and often accompanied by disc herniation (DH) and/or degenerative spondylolisthesis (DS). Given the high prevalence of the disease (up to 20% according to some estimates) and the high costs associated with its care, there is a need to explore novel therapies such as regenerative medicine. Exploring these novel therapies first warrants investigation of molecular pathways underlying these disorders. Here, we show results from next generation RNA sequencing (RNA-seq) on mRNA isolated from 10 human nucleus pulposus (NP) samples of lumbar degenerated discs (DH and DS; n = 5 for each tissue) and other musculoskeletal tissues (Bone, cartilage, growth plate, and muscle; n = 7 for each tissue). Pathway and network analyses based on gene ontology (GO) terms were used to identify the biological functions of differentially expressed mRNAs. A total of 701 genes were found to be significantly upregulated in lumbar NP tissue compared to other musculoskeletal tissues. These differentially expressed mRNAs were primarily involved in DNA damage, immunity and G1/S transition of mitotic cell cycle. Interestingly, DH-specific signaling genes showed major network in chemotactic (e.g., CXCL10, CXCL11, IL1RL2 and IL6) and matrix-degrading pathway (e.g., MMP16, ADAMTSL1, 5, 8, 12, and 15), while DS-specific signaling genes were found to be those involved in cell adhesion (e.g., CDH1, EPHA1 and EFNA2) and inflammatory cytokines (e.g., CD19, CXCL5, CCL24, 25 and XCL2). Our findings provide new leads for therapeutic drug discovery that would permit optimization of medical or pharmacological intervention for cases of lumbar DDD.

Baicalein Inhibits the IL-1β-Induced Inflammatory Response in Nucleus Pulposus Cells and Attenuates Disc Degeneration In vivo

Intervertebral disc degeneration (IDD) is widely considered one of the main causes of low back pain, which is a chronic progressive disease closely related to inflammation and degeneration of nucleus pulposus (NP) cells. Baicalein is a natural bioactive compound with anti-inflammatory effects in different diseases, including inhibition of the inflammatory response in chondrocytes, whose morphology and avascular supply are similar to those of NP cells. Therefore, we hypothesized that baicalein may have a therapeutic effect on IDD by suppressing the inflammatory response. In vitro, NP cells were pretreated with baicalein for 2 h and then incubated with IL-1β for 24 h. We found that baicalein not only inhibited the overexpression of inflammatory cytokine production, including NO, PGE2, TNF-α, and IL-6, but also suppressed the expression of COX-2 and iNOS. The IL-1β-induced overexpression of MMP13 and ADAMTS5 and degradation of aggrecan and type II collagen were reversed by baicalein in a dose-dependent manner. Mechanistically, we found that baicalein suppressed the IL-1β-induced activation of the NF-κB and MAPK pathways. Moreover, an in vivo study demonstrated that baicalein treatment could ameliorate IDD in a puncture-induced rat model. Thus, baicalein has great value as a potential therapeutic agent for IDD.

Melatonin Protects Intervertebral Disc from Degeneration by Improving Cell Survival and Function via Activation of the ERK1/2 Signaling Pathway

Melatonin, a neuroendocrine hormone secreted by the pineal body, has a positive effect on intervertebral disc degeneration. The present study is aimed at investigating the biological role of melatonin in intervertebral disc degeneration and its underlying mechanism. A human nucleus pulposus cell (NPC) line was exposed to melatonin at different concentrations. Cell proliferation was measured by CCK-8 assay. Cell cycle and apoptosis were analyzed by flow cytometry. Western blot was performed to measure the protein expression of indicated genes. A rabbit model of intervertebral disc degeneration was established to detect the role and mechanism of melatonin on intervertebral disc degeneration. Our study showed that melatonin promoted NPC viability and inhibited cell arrest. Furthermore, melatonin treatment led to the upregulation of collagen II and aggrecan and downregulation of collagen X. Moreover, melatonin significantly elevated the activity of the ERK signaling pathway. Inhibition of the ERK1/2 signals reversed the role of melatonin in the regulation of NPCs both in vitro and in vivo. Melatonin increased NPC viability through inhibition of cell cycle arrest and apoptosis. Moreover, melatonin promoted the secretion of functional factors influencing the nucleus pulposus cell physiology and retarded cell degeneration. Our results suggest that melatonin activated the ERK1/2 signaling pathway, thereby affecting the biological properties of the intervertebral disc degeneration.

SYMPTOMATIC INTRADISCAL VACUUM PHENOMENON

ABSTRACT Objective: Intradiscal vacuum phenomenon (IVP) is a common finding in the study of degenerative disc disease. Discogenic low back pain can be manifested in different ways, including irradiation to the lower limbs. This study aims to acknowledge the complementary studies used to diagnose IVP, determine their sensitivity, and assess the correlation between clinical and imaging findings. Methods: This is a descriptive, observational and prospective study involving clinical and imaging evaluation of 100 patients with IVP, using dynamic and plain radiographs, computed tomography and magnetic resonance imaging. The factors of analysis include sex, age, reason for consultation, visual analogue scale, irradiation and topography of the pain, the existence of sciatica and claudication, smoking status, and body mass index. Results: The overall average age of the patients was 64.6 years, who particularly evidence degenerative pathology. IVP was observed in 99 CT, 85 dynamic radiographs, 80 plain radiographs and 65 nuclear magnetic resonance images (MRI). Conclusion: The most useful studies for diagnosing the vacuum disc phenomenon are plain and dynamic radiographs, tomography, and magnetic resonance. The CT is the most sensitive imaging study for IVP detection, followed by dynamic radiographs obtained during extension. A correlation was observed between older age, overweight, and IVP. Level of evidence IV; Case-series.

Long non-coding RNA HOTAIR modulates intervertebral disc degenerative changes via Wnt/β-catenin pathway

BACKGROUND

Intervertebral disc degeneration (IDD) has a complicated and enigmatic pathogenic process. Accumulating evidence shows that long non-coding RNAs (LncRNAs) play a role in the pathogenesis of IDD. This study aimed to investigate the expression and role of the LncRNA HOTAIR in IDD pathogenesis.

METHODS

Nucleus pulposus (NP) tissue samples from 10 patients with idiopathic scoliosis and 10 patients with lumbar disc herniation were collected. qRT-PCR was used to assess the expression of HOTAIR and ECM-related genes; western blotting was used to detect the expression of senescence biomarkers, apoptosis-related proteins, and Wnt/β-catenin pathway; flow cytometry was used to detect apoptosis; and the MTT assay was used to determine cell proliferation. Moreover, a classic needle-punctured rat tail model was used to investigate the role of HOTAIR in IDD in vivo.

RESULTS

The results showed that the expression of HOTAIR significantly increased during IDD progression. The overexpression of HOTAIR was found to induce nucleus pulposus (NP) cell senescence, apoptosis, and extracellular matrix (ECM) degradation. HOTAIR silencing by RNA interference in NP cells prevented interleukin-1β-induced NP cell senescence, apoptosis, and ECM degradation. Furthermore, we found that the Wnt/β-catenin pathway played a role in regulating HOTAIR to induce these changes in NP cells. Moreover, HOTAIR inhibition in a rat model effectively attenuated IDD symptoms in vivo.

CONCLUSIONS

Our findings confirmed that HOTAIR promoted NP cell senescence, apoptosis, and ECM degradation via the activation of the Wnt/β-catenin pathway, while silencing HOTAIR attenuated this degeneration process, indicating a potential therapeutic target against IDD.

Sex Differences in Rat Intervertebral Disc Structure and Function Following Annular Puncture Injury

STUDY DESIGN

A rat puncture injury intervertebral disc (IVD) degeneration model with structural, biomechanical, and histological analyses.

OBJECTIVE

To determine if males and females have distinct responses in the IVD after injury.

SUMMARY OF BACKGROUND DATA

Low back pain (LBP) and spinal impairments are more common in women than men. However, sex differences in IVD response to injury have been underexplored, particularly in animal models where sex differences can be measured without gender confounds.

METHODS

Forty-eight male and female Sprague Dawley rats underwent sham, single annular puncture with tumor necrosis factor α (TNFα) injection (1×), or triple annular puncture with TNFα injection (3×) surgery. Six weeks after surgery, lumbar IVDs were assessed by radiologic IVD height, spinal motion segment biomechanical testing, histological degeneration grading, second harmonic generation (SHG) imaging, and immunofluorescence for fibronectin and α-smooth muscle actin.

RESULTS

Annular puncture injuries significantly increased degenerative grade and IVD height loss for males and females, but females had increased degeneration grade particularly in the annulus fibrosus (AF). Despite IVD height loss, biomechanical properties were largely unaffected by injury at 6 weeks. However, biomechanical measures sensitive to outer AF differed by sex after 3× injury-male IVDs had greater torsional stiffness, torque range, and viscoelastic creep responses. SHG intensity of outer AF was reduced after injury only in female IVDs, suggesting sex differences in collagen remodeling. Both males and females exhibited decreased cellularity and increased fibronectin expression at injury sites.

CONCLUSION

IVD injury results in distinct degeneration and functional healing responses between males and females. The subtle sex differences identified in this animal model suggest differences in response to IVD injury that might explain some of the variance observed in human LBP, and demonstrate the need to better understand differences in male and female IVD degeneration patterns and pain pathogenesis.

LEVEL OF EVIDENCE

N/A.

360-Degree Complex Primary Reconstruction Using Porous Tantalum Cages for Adult Degenerative Spinal Deformity

STUDY DESIGN

Retrospective cohort study.

OBJECTIVE

To assess both implant performance and the amount of correction that can be achieved using multilevel anterior lumbar interbody fusion (ALIF).

METHODS

Retrospective cohort study (n = 178) performed over a 4-year period. Surgical variables examined included blood loss, operative time, perioperative complications, and secondary/revision procedures. Follow-up radiographic assessment was performed to record implant-related problems. Radiographic parameters were examined pre- and postoperatively. Health-related quality of life (HRQOL) outcome measures were collected preoperatively and at 6 weeks, 6 months, 1 year, and 2 years postoperatively. Descriptive and comparative statistical analysis, using paired-sample t test and repeated-measures analysis of variance (rANOVA), was performed.

RESULTS

Lumbar lordosis increased from 42° ± 17° preoperatively to 55° ± 11° postoperatively (P < .001). The visual analog scale back pain mean score improved from 8.3 ± 1.5 preoperatively to 2.6 ± 2.4 at 2 years (P < .001). The mean Oswestry Disability Index improved from 69.5 ± 21.5 preoperatively to 19.9 ± 15.2 at 2 years (P < .001). The EQ-5D mean score improved from 0.2 ± 0.2 preoperatively to 0.8 ± 0.1 at 2 years (P = .02). There were no neurological, vascular, or visceral approach-related injuries reported. No rod breakages and no symptomatic nonunions occurred. There was one revision procedure performed for fracture.

CONCLUSIONS

The use of porous tantalum cages as part of a 360-degree fusion to treat adult degenerative spinal deformity has been demonstrated to be a safe and effective strategy, leading to good clinical, functional, and radiographic outcomes in the short term.

First results of multicortical screw anchoring compared with conventional bicortical screw placement in the sacrum: A biomechanical investigation of a new screw design

BACKGROUND

Bicortical screw fixation is an established technique to increase screw strength in vertebral bodies, although it is associated with several complications, for example screw-loosening. Cement augmentation can increase stability of screw-fixation but can also cause various complications, such as cement-leakage or cement embolism. In this study, we tested a new, multicortical screw fixation technique in the sacrum.

METHODS

Four fresh-frozen sacrums were used. In group 1, standard screw insertion, with sagittal parallel and axial convergent screw-drive was performed. In group 2, the screw-drive of the first screw was similar to the screw-drive in group 1. In addition, a second screw was inserted descending into the intended hole in the head of the screw and at a stable angle. Therefore, the screws of the multiloc humerus nail-system (Synthes) were used. The specimens were connected to a testing-machine and underwent cyclic axial loading with an increase in the load after each completed stage.

FINDINGS

Multicortical screw fixation leads to a significant increase in the number of completed cycles and a significantly increased load until failure.

INTERPRETATION

Multicortical screw fixation in the sacrum offers a stronger attachment of the screws. In the future, multicortical implants, which fulfil the criteria demanded in spine surgery, can offer higher stability and may decrease the loosening rates of the implanted screws.

Sirtuin 2 expression suppresses oxidative stress and senescence of nucleus pulposus cells through inhibition of the p53/p21 pathway

Intervertebral disc degeneration (IDD) is a kind of disease associated with nucleus pulposus (NP) cell senescence. Previous studies have shown that the sirtuin family plays an extremely important role in the progress of cell aging. However, whether sirtuin2 (Sirt2) protects against IDD remains unknown. The aim of this study was to determine whether Sirt2 protected NP from degradation in IDD. The expression of Sirt2 in different degree of degenerate disc tissues was determined by reverse transcription-polymerase chain reaction. Interleukin 1 beta (IL-1β) was used to stimulate the degeneration of NP cells. Subsequently, lentivirus transfection was performed to increase Sirt2 expression in vitro. Meanwhile, the function of Sirt2 overexpression in the progress of NP cell degeneration was evaluated. Our study showed that the expression of Sirt2 markedly decreased in severe degenerated disc tissues. IL-1β significantly promoted the progress of IDD. Meanwhile, overexpression of Sirt2 could reverse the effects of IL-1β. The data also revealed that Sirt2 overexpression obviously increased the production of antioxidant SOD1/2 and suppressed oxidative stress in the disc. Moreover, p53 and p21 could be significantly suppressed by Sirt2 overexpression. These results suggested that Sirt2 prevented NP degradation via restraining oxidative stress and cell senescence through inhibition of the p53/p21 pathway. Furthermore, Sirt2 might become a novel target for IDD therapy in the future.

Updated imaging does not affect revision rates in adults undergoing spine surgery for lumbar degenerative disease

OBJECTIVEDiagnostic workup for lumbar degenerative disc disease (DDD) includes imaging such as radiography, MRI, and/or CT myelography. If a patient has unsuccessful nonoperative treatment, the surgeon must then decide if obtaining updated images prior to surgery is warranted. The purpose of this study was to investigate whether the timing of preoperative neuroimaging altered clinical outcome, as reflected by the subsequent rate of revision surgery, in patients with degenerative lumbar spinal pathology.METHODSFrom the Health Care Service Corporation administrative claims database, adult patients (minimum age 55 years old) with lumbar DDD who underwent surgery including posterior lumbar decompression with and without fusion (1-2 levels) and at least 5 years of continuous coverage after the index surgery were identified. The chi-square test was used to determine differences in revision rates stratified by timing of each imaging procedure relative to the index procedure (< 6 months, 6-12 months, 12-24 months, or > 24 months).RESULTSOf 28,676 cases identified, 5128 (18%) had revision surgery within 5 years. The timing of preoperative MRI or plain radiography was not associated with revision surgery. Among the entire cohort, there was a lower incidence of revision surgery in patients who had a CT myelogram within 1 year prior to the index surgery (p = 0.017). This observation was strongest in patients undergoing decompression only (p = 0.002), but not significant in patients undergoing fusion (p = 0.845).CONCLUSIONSRoutine reimaging prior to surgery, simply because the existing MRI is 6-12 months old, may not be beneficial, at least as reflected in subsequent revision rates. The study also suggests that there may be a subset of patients for whom preoperative CT myelography reduces revision rates. This topic has important financial implications and deserves further study in a more granular data set.

The Recent Trend in Diagnosis and Treatment of Chronic Low Back Pain

INTRODUCTION

Development of evidence-based medicine has made a big change in diagnosis and treatment of chronic low back pain. The recent trend is assessed through a review of literature.

METHODS

The articles published in these 10 years are reviewed, and important points are examined.

RESULTS

In diagnosis, challenges for history taking and limit of imaging or clinical guidelines are revealed. In treatment, cognitive behavioral treatment and exercises are proved effective. Sleep disturbance has recently attracted attention as a factor associated with low back pain. Cost-effectiveness of diagnosis and treatment modalities has come to be emphasized.

CONCLUSIONS

Diagnosis and treatment of chronic low back pain have been significantly changing. Multidisciplinary and multidimensional approach is essential. Chronic low back pain should be treated as a total pain, not a local pain.

Treatment of lumbar degenerative disc disease-associated radicular pain with culture-expanded autologous mesenchymal stem cells: a pilot study on safety and efficacy

Background

Degenerative disc disease (DDD) is a common cause of lower back pain with radicular symptoms and has a significant socioeconomic impact given the associated disability. Limited effective conservative therapeutic options result in many turning to surgical alternatives for management, which vary in the rate of success and also carry an increased risk of morbidity and mortality associated with the procedures. Several animal based studies and a few human pilot studies have demonstrated safety and suggest efficacy in the treatment of DDD with mesenchymal stem cells (MSCs). The use of bone marrow-derived MSCs for the treatment of DDD is promising and in the present study we report on the safety and efficacy findings from a registry based proof of concept study using a percutaneous intradiscal injection of cultured MSCs for the management of DDD with associated radicular symptoms.

Methods

Thirty-three patients with lower back pain and disc degeneration with a posterior disc bulge diagnosed on magnetic resonance imaging (MRI) met the inclusion criteria and were treated with culture-expanded, autologous, bone marrow-derived MSCs. Prospective registry data was obtained at multiple time intervals up to 6 years post-treatment. Collected outcomes included numeric pain score (NPS), a modified single assessment numeric evaluation (SANE) rating, functional rating index (FRI), measurement of the intervertebral disc posterior dimension, and adverse events.

Results

Three patients reported pain related to procedure that resolved. There were no serious adverse events (i.e. death, infection, or tumor) associated with the procedure. NPS change scores relative to baseline were significant at 3, 36, 48, 60, and 72 months post-treatment. The average modified SANE ratings showed a mean improvement of 60% at 3 years post-treatment. FRI post-treatment change score averages exceeded the minimal clinically important difference at all time points except 12 months. Twenty of the patients treated underwent post-treatment MRI and 85% had a reduction in disc bulge size, with an average reduction size of 23% post-treatment.

Conclusions

Patients treated with autologous cultured MSCs for lower back pain with radicular symptoms in the setting of DDD reported minor adverse events and significant improvements in pain, function, and overall subjective improvement through 6 years of follow-up.

NCT03011398. A Clinical Registry of Orthobiologics Procedures. https://clinicaltrials.gov/ct2/show/NCT03011398?term=orthobiologics&rank=1

NSAID use in intervertebral disc degeneration: what are the effects on matrix homeostasis in vivo?

BACKGROUND CONTEXT

Non-steroidal anti-inflammatory drugs (NSAIDs) are a widely used treatment for low back pain (LBP). Literature on NSAID use in articular cartilage has shown detrimental effects; however, minimal data exist to detail the effects of NSAIDs in intervertebral disc degeneration (IDD). As IDD is a major cause of LBP, we explored the effects of indomethacin, a commonly used NSAID, on disc matrix homeostasis in an animal model of IDD.

PURPOSE

This study aimed to determine the effects of oral indomethacin administration on IDD in an in vivo rabbit model. This study hypothesized that indomethacin use would accelerate the progression of IDD based upon serial imaging and tissue outcomes.

STUDY DESIGN/SETTING

This was a laboratory-based, controlled, in vivo evaluation of the effects of oral indomethacin administration on rabbit intervertebral discs.

METHODS

Six skeletally mature New Zealand white rabbits were divided into two groups: disc puncture alone to induce IDD (Puncture group) and disc puncture plus indomethacin (Punc+Ind group). The Punc+Ind group received daily administration of 6mg/kg oral indomethacin. Serial magnetic resonance imaging (MRI) was obtained at 0, 4, 8, and 12 weeks. The MRI index and the nucleus pulposus (NP) area were calculated. Discs were harvested at 12 weeks for determination of disc glycosaminoglycan (GAG) content, relative gene expression measured by real-time polymerase chain reaction, and histologic analyses.

RESULTS

The MRI index and the NP area of punctured discs in the Punc+Ind group demonstrated no worsening of degeneration compared with the Puncture group. Histologic analysis was consistent with less severe disc degeneration in the Punc+Ind group. Minimal differences in gene expression of matrix genes were observed between Puncture and Punc+Ind groups. The GAG content was higher in animals receiving indomethacin in both annulus fibrosus and NP at adjacent uninjured discs.

CONCLUSIONS

Oral indomethacin administration did not result in acceleration of IDD in an in vivo rabbit model. Future research is needed to ascertain long-term effects of indomethacin and other NSAIDs on disc matrix homeostasis.

Evidence Gaps in the Use of Spinal Cord Stimulation for Treating Chronic Spine Conditions

STUDY DESIGN

A review of literature.

OBJECTIVE

The aim of this study was to define and explore the current evidence gaps in the use of spinal cord stimulation (SCS) for treating chronic spine conditions.

SUMMARY OF BACKGROUND DATA

Although over the last 40 years SCS therapy has undergone significant technological advancements, evidence gaps still exist.

METHODS

A literature review was conducted to define current evidence gaps for the use of SCS. Areas of focus included 1) treatment of cervical spine conditions, 2) treatment of lumbar spine conditions, 3) technological advancement and device selection, 4) appropriate patient selection, 5) the ability to curb pharmacological treatment, and 6) methods to prolong efficacy over time. New SCS strategies using advanced waveforms are explored.

RESULTS

The efficacy, safety, and cost-effectiveness of traditional SCS for chronic pain conditions are well-established. Evidence gaps do exist. Recently, advancement in waveforms and programming parameters have allowed for paresthesia-reduced/free stimulation that in specific clinical areas may improve clinical outcomes. New waveforms such as 10-kHz high-frequency have resulted in an improvement in back coverage. To date, clinical efficacy data are more prevalent for the treatment of painful conditions originating from the lumbar spine in comparison to the cervical spine.

CONCLUSION

Evidence gaps still exist that require appropriate study designs with long-term follow-up to better define and improve the use of this therapy for the treatment of chronic spine pain in both the cervical and lumbar regions.

LEVEL OF EVIDENCE

N/A.

Sirtuin 6 prevents matrix degradation through inhibition of the NF-κB pathway in intervertebral disc degeneration

Intervertebral disc degeneration (IDD) is marked by imbalanced metabolism of the extracellular matrix (ECM) in the nucleus pulposus (NP) of intervertebral discs. This study aimed to determine whether sirtuin 6 (SIRT6), a member of the sirtuin family of nicotinamide adenine dinucleotide-dependent deacetylases, protects the NP from ECM degradation in IDD. Our study showed that expression of SIRT6 markedly decreased during IDD progression. Overexpression of wild-type SIRT6, but not a catalytically inactive mutant, prevented IL-1β-induced NP ECM degradation. SIRT6 depletion by RNA interference in NP cells caused ECM degradation. Moreover, SIRT6 physically interacted with nuclear factor-κB (NF-κB) catalytic subunit p65, transcriptional activity of which was significantly suppressed by SIRT6 overexpression. These results suggest that SIRT6 prevented NP ECM degradation in vitro via inhibiting NF-κB-dependent transcriptional activity and that this effect depended on its deacetylase activity.

Evaluation of the Etoricoxib-Mediated Pain-Relieving Effect in Patients Undergoing Lumbar Fusion Procedures for Degenerative Lumbar Scoliosis: A Prospective Randomized, Double-Blind Controlled Study

This randomized, double-blind study was carried out to evaluate the effectiveness of etoricoxib in controlling the pain during lumbar fusion surgery of the degenerative lumbar scoliosis patients. We found that perioperative use of etoricoxib produced a significant reduction in the degree of pain compared to the patients treated with placebo. Etoricoxib eased the pain and helped to manage the discomfort of lumbar fusion surgery. In addition, etoricoxib was well tolerated as it caused no serious adverse reaction, suggesting a safe profile. Etoricoxib also appeared to ensure and promote the positive effect of surgery, however, insignificantly. Thus, the results suggest that etoricoxib was effective in safely managing the pain during the lumbar fusion surgery and recovery thereafter.

Evaluation of Aesculap Implant Systems activl Artificial Disc for the treatment of degenerative disc disease

INTRODUCTION

A primary cause of chronic low back pain and disability is lumbar degenerative disc disease (DDD). Surgical treatments are available for DDD including fusion or lumbar total disc replacement (TDR). Lumbar TDR is performed as a motion-preserving alternative to lumbar fusion. There are several marketed lumbar TDR devices including the Aesculap Implant Systems activL Artificial Disc, Charité Artificial Disc and the ProDisc-L Total Disc Replacement. Areas covered: Considering the various surgical options by which lumbar DDD can be managed, here we evaluate the biologic and biomechanical benefits and concerns of the Aesculap activL Artificial Disc. We review the use of the activL Artificial Disc compared to other lumbar TDRs and an alternative to fusion for skeletally mature patients diagnosed with isolated, symptomatic DDD. Expert commentary: Short-term follow-up studies suggest that under the right circumstances and precise patient selection, lumbar TDR with the Aesculap activL Artificial Disc is a safe and effective alternative to lumbar fusion. Long-term clinical data will provide information about the potential for adjacent level disease, effects of implant wear, and indications for revision surgery. Future clinical and biomechanical studies, as well as device-specific long-term outcome and comparison studies, will assist surgical decision making.

Operative Management of Lumbar Degenerative Disc Disease

Lumbar degenerative disc disease is extremely common. Current evidence supports surgery in carefully selected patients who have failed non-operative treatment and do not exhibit any substantial psychosocial overlay. Fusion surgery employing the correct grafting and stabilization techniques has long-term results demonstrating successful clinical outcomes. However, the best approach for fusion remains debatable. There is some evidence supporting the more complex, technically demanding and higher risk interbody fusion techniques for the younger, active patients or patients with a higher risk of non-union. Lumbar disc arthroplasty and hybrid techniques are still relatively novel procedures despite promising short-term and mid-term outcomes. Long-term studies demonstrating superiority over fusion are required before these techniques may be recommended to replace fusion as the gold standard. Novel stem cell approaches combined with tissue engineering therapies continue to be developed in expectation of improving clinical outcomes. Results with appropriate follow-up are not yet available to indicate if such techniques are safe, cost-effective and reliable in the long-term.

TGF-βl Suppresses Inflammation in Cell Therapy for Intervertebral Disc Degeneration

Recent studies suggest that cell therapy may be an effective way to repair intervertebral disc degeneration. As a strong immune suppressor, TGF-β1 has been shown to inhibit inflammation respond effectively. The objective of this study was to explore the effects of TGF-β1 during bone marrow mesenchymal stem cells-based therapy for disc degeneration. In vitro assays demonstrated that co-culturing of nucleus pulposus cells with bone marrow mesenchymal stem cells resulted in significantly higher levels of TGF-βl secretion. This increase inhibited IκB phosphorylation and NF-κB activation, detected by western blot analysis. Meanwhile, in a rabbit model, MRI analysis revealed significant recovery of signal intensity in the degenerative discs of rabbits receiving cells transplantation, than receiving cells treated with a TGF-β1 inhibitor or saline. These findings indicated that enhanced TGF-β1 production recovered the degeneration of intervertebral disc. And also immunohistochemical staining detected enhanced collagen II expression in the rabbits treated with cell transplantation. However, the NF-κB positive cells were significantly less than other two control groups. Thus, cell therapy promoted TGF-β1 expression in nucleus pulposus, leading to anti-inflammatory effects via the inhibition of NF-κB, and the amelioration of disc degradation due to increased expression of collagen II and aggrecan in degenerative intervertebral disc.

Molecular basis of intervertebral disc degeneration and herniations: what are the important translational questions?

BACKGROUND

Intervertebral disc degeneration is a common condition with few inexpensive and effective modes of treatment, but current investigations seek to clarify the underlying process and offer new treatment options. It will be important for physicians to understand the molecular basis for the pathology and how it translates to developing clinical treatments for disc degeneration. In this review, we sought to summarize for clinicians what is known about the molecular processes that causes disc degeneration.

RESULTS

A healthy disc requires maintenance of a homeostatic environment, and when disrupted, a catabolic cascade of events occurs on a molecular level resulting in upregulation of proinflammatory cytokines, increased degradative enzymes, and a loss of matrix proteins. This promotes degenerative changes and occasional neurovascular ingrowth potentially contributing to the development of pain. Research demonstrates the molecular changes underlying the harmful effects of aging, smoking, and obesity seen clinically while demonstrating the variable influence of exercise. Finally, oral medications, supplements, biologic treatments, gene therapy, and stem cells hold great promise but require cautious application until their safety profiles are better outlined.

CONCLUSIONS

Intervertebral disc degeneration occurs where there is a loss of homeostatic balance with a predominantly catabolic metabolic profile. A basic understanding of the molecular changes occurring in the degenerating disc is important for practicing clinicians because it may help them to inform patients to alter lifestyle choices, identify beneficial or harmful supplements, or offer new biologic, genetic, or stem cell therapies.

Retrospective lumbar fusion outcomes measured by ODI sub-functions of 100 consecutive procedures

INTRODUCTION

Low back pain has been quite prevalent in the general population. Chronic low back pain can be defined as back pain lasting for more than 12 weeks. For chronic symptoms, fusion surgeries are the most common surgeries to alleviate the pain. Visual Analog Scale (VAS) is a measurement for subjective characteristics or attitudes that can be difficult to be directly measured. Respondents specify their level of agreement to a statement by indicating a position along a continuous line between two end points.

AIM

The purpose of this study is to investigate patient-reported pain using our own modified ODI with sub-functions. This allowed the study to show how patient outcomes differ with and without co-morbidity as well as functional outcomes after spinal fusion for degenerative disk disease (DDD) with the consistency of using one device and all procedures performed by the same surgeon.

MATERIALS AND METHODS

One hundred patients with DDD were treated with spinal fusion using one device. All procedures were performed by the same surgeon over a 3-year period. Patients were evaluated with discography and MRI preoperatively. Diagnosis of DDD was made when imaging showed bony segment erosion with decreased disc space >50%. Fifty-six patients participated in the initial questionnaire and their data were tabulated and statistically analyzed. Twenty male patients aged 49-85 (median: 67, mean: 66), and thirty-six female patients aged 30-84 (median: 67, mean 64) responded to the questionnaire. There were no differences in pain total by gender, fusion level, single/multiple fusions, degenerative versus deformity condition, type of graft, and lumber area (all p values ≥ 0.15).

RESULTS

Five-year pain measurements used by the VAS questionnaire as well as pain and functional outcomes measured by the ODI after lumbar fusion were superior to the results at 2 years (p = 0.025). Improvement was seen in all of the ODI sub-scores after 5 years, however, only physical function and social function reached statistical significance (p = 0.016 and 0.061, respectively).

CONCLUSION

Successful outcomes were demonstrated for each of the categories assessed and no statistical differences were seen in the ODI % for any comparison after 5 years on 19% of data reported which may have limited forecast reliability. Our data suggest that post-operative outcome is independent of preoperative condition, procedure to be preformed, age, and BMI. Our data support the continual practice of spinal fusion for the treatment of degenerative disk disease.

Adjacent segment disease in degenerative pathologies with posterior instrumentation

OBJECTIVE: To establish the real incidence of adjacent segment disease after fusion, and to identify the levels and predisposing factors for the pathology, as well as the functional results. METHODS: a retrospective case series study with level of evidence IIB, in a sample of 179 patients diagnosed with stenosis of the lumbar spine, spondylolisthesis and degenerative scoliosis, submitted to surgery in the period 2005 to December 2013, with posterior instrumentation and posterolateral fusion, with follow-up from 2007 until May 2014, in which the symptomology and radiographic findings were evaluated, to establish the diagnosis and treatment. RESULTS: the study included 179 patients diagnosed with stenosis of the lumbar spine (n=116), isthmic and degenerative spondylolisthesis (n=50) and degenerative scoliosis (n=13); during the study, 20 cases of adjacent level segment were identified, 80% of which were treated surgically with extension of the instrumentation, while 20% were treated conservatively with NSAIDs and therapeutic blocks. CONCLUSION: An incidence of 11% was found, with an average of 3.25 years in diagnosis and treatment, a prevalence of females and diagnosis of stenosis of the lumbar canal on posterior instrumentation, a predominance of levels L4-L5; 80% were treated with extension of the instrumentation. The complications were persistent radiculopathy, infection of the surgical wound, and one death due to causes not related to the lumbar pathology.

National trends in the surgical treatment for lumbar degenerative disc disease: United States, 2000 to 2009

BACKGROUND CONTEXT

Surgical treatment for lumbar degenerative disc disease (DDD) remains controversial. Options include anterior lumbar interbody fusion, posterior approach fusion procedures such as posterior lumbar interbody fusion (PLIF) and posterolateral lumbar fusion (PLF), anterior and posterior lumbar fusion (APLF), and total disc replacement (TDR). However, the trends during the last decade are uncertain.

PURPOSE

To examine the trends in the surgical treatment for lumbar DDD on a national level.

STUDY DESIGN

A retrospective analysis of population-based national hospital discharge data collected for the Nationwide Inpatient Sample (NIS).

PATIENT SAMPLE

In the NIS from 2000 to 2009, patients aged 18 years or older with primary diagnosis of lumbar/lumbosacral DDD who underwent surgical treatment were included.

OUTCOME MEASURES

Trends in the surgical treatment for lumbar DDD.

METHODS

Clinical data were derived from the NIS between 2000 and 2009. Patients aged 18 years or older with a primary diagnosis of lumbar/lumbosacral DDD who underwent spinal fusion or TDR were identified. Data regarding patient- and health care system-related characteristics were retrieved and analyzed.

RESULTS

A total of 380,305 patients underwent surgical treatment for lumbar DDD between 2000 and 2009. Population adjusted incidence increased 2.4-fold from 2000 to 2009. Among the procedures, APLF increased 3.0-fold and PLIF/PLF increased 2.8-fold. Total disc replacement did not increase significantly. Anterior lumbar interbody fusion was performed in 16.8% of patients, PLIF/PLF in 67.9%, APLF in 13.6%, and TDR in 1.8%. Surgical treatment for lumbar DDD was 1.8 times more common in the Midwest region and 1.7 times more common in the South region than in the Northeast region. Total disc replacement was more common in younger patients and in the Northeast region. Poterior lumbar interbody fusion/PLF was more common in older patients and in the South region.

CONCLUSIONS

During the last decade, surgical treatment for lumbar DDD has increased 2.4-fold in the United States. Although all fusion procedures significantly increased, TDR did not increase. Surgical treatment for lumbar DDD was more common in the Midwest and South regions. Trends in the procedures were different depending on the age group and hospital region.

Nonoperative management of discogenic back pain: a systematic review

STUDY DESIGN

Systematic review of the literature.

OBJECTIVE

A systematic evaluation of the literature was performed to investigate current nonoperative management of the treatment of discogenic low back pain.

SUMMARY OF BACKGROUND DATA

Back pain is a major health care concern with up to 39% being discogenic in origin according to one study. Nonoperative therapy is likely to be the initial treatment strategy for discogenic low back pain.

METHODS

PubMed, EMBASE, and Cochrane Central Register of Controlled Trials were searched for clinical studies evaluating nonoperative methods of treating discogenic back pain that were published between 2000 and 2012. Only prospective randomized controlled studies that compared a nonsurgical intervention with sham or placebo therapy were included. After removal of duplicate citations, a total of 226 articles were initially identified from the search terms. From these, we identified 11 randomized controlled trials (RCTs) from which data analysis was performed.

RESULTS

The 11 RCTs investigated traction therapy, injections, and ablative techniques. Results from 5 RCTs investigating methylene blue injection, steroid injection, ramus communicans ablation, intradiscal electrothermal therapy, and biacuplasty favored intervention over sham therapy. However, results from the study on methylene blue injections have not been replicated in other RCTs. Evaluation of the selection criteria used in the studies on ramus communicans ablation and intradiscal biacuplasty and a stratified analysis of results from the RCTs on intradiscal electrothermal therapy casts doubt on whether the conclusions from these RCTs can be applied to the general patient population with discogenic pain.

CONCLUSION

There are few high-quality studies evaluating nonoperative treatments for reducing discogenic low back pain. Although conclusions from several studies favor intervention over sham, it is unclear whether these interventions confer stable long-term benefit. There is some promise in newer modalities such as biacuplasty; however, more inclusive studies need to be performed.

Stand-alone anterior lumbar interbody fusion for degenerative disc disease of the lumbar spine: results with a 2-year follow-up

STUDY DESIGN

Retrospective chart review.

OBJECTIVE

To report outcomes of a consecutive series of patients diagnosed with degenerative disc disease (DDD) between L4 and S1, treated with stand-alone anterior lumbar interbody fusion (ALIF, either 1 or 2 levels) and use of recombinant human bone morphogenetic protein 2 for bony fusion with instrumented fixation.

SUMMARY OF BACKGROUND DATA

Degeneration of the lumbar spine is described as lumbar spondylosis, or DDD. To treat DDD, surgical interventions include: ALIF, circumferential fusion (360° fusion), posterior spinal fusion, and total disc replacement. Currently, there has been paucity in the literature on the evaluation of ALIFs.

METHODS

Researchers reviewed a consecutive series of patients with DDD who had undergone a 1-level or 2-level ALIF between 2005 and 2010, with the use of recombinant human bone morphogenetic protein 2. Patients' clinical and functional outcomes were documented. Radiographs were analyzed for disc height, mean optical density, and integrated optical density. Operative time, length of hospital stay, and estimated blood loss were also reported.

RESULTS

Patients' 2-year Oswestry Disability Index and visual analogue scale presurgery scores significantly improved (P ≤ 0.0001). Patients' 2-year postoperative disc height was significantly greater than the preoperative disc height at the fused level (P ≤ 0.0001); there was no significant difference at the level adjacent to fusion. Majority of patients (107 of 115, 93.0%) satisfied fusion criteria based on mean optical density. Intraoperative time, estimated blood loss, and hospital stay was significantly fewer with 1-level and 2-level ALIFs than 360° fusions and total disc replacement.

CONCLUSION

Stand-alone ALIF used to treat DDD can produce comparative clinical and functional outcomes. ALIFs showed significant decreases in blood loss, operative time, and hospital stay. Furthermore, at 2 years' time, mean optical density suggests high rate of bony fusion, and no significant loss of disc height was noted at the adjacent level.

LEVEL OF EVIDENCE

4.

Primary care-based facial pain unit in Vantaa: the first experiences 2003–2009

As an attempt to tackle the challenge in serving facial pain patients, the first primary care-based facial pain unit was founded in 2003 as part of public dental primary care of Vantaa, Finland. Data were collected, consisting of sex, age, sources of referrals, reasons for seeking care, diagnoses made, therapeutic procedures, and numbers of visits to dentists and phone consultations. To describe the development of the present pain management system, we divided the observation periods into two parts: 2003-2006 and 2007-2009 and compared frequencies of the studied parameters between the two follow-up periods. During 2003-2006, 370 patients were examined and the number of visits was 659, corresponding patients' number was 437 and visits' number 960 during 2007-2009. Referrals to the primary care facial pain unit came from primary care dentists (80%), respective primary care pain unit GPs (6%), oral hygienists (3%) and ordinary GPs (2%). Four percentage of the patients' referrals came from secondary and tertiary care clinics of various types and 5% from private sector dentists and specialists. The average number of telephone consultations per year increased from 51 to 300 between study periods. During the follow-up period, the main reason for seeking care from our unit was temporomandibular disorders. Education in self-care, oral appliance therapy and physiotherapy were mostly used as management for these pain problems. The facial pain management unit in primary health care could be a useful model to serve increasing numbers of chronic facial pain patients.

Distribution pattern of surgically treated symptomatic prolapsed lumbar and sacral intervertebral discs in males

Background:

The pattern of distribution of surgically treated symptomatic prolapsed lumbar and sacral intervertebral discs has been published, though scantily, especially in males. We decided to look at our own series, compare and contrast ours with some of those published.

Materials and Methods:

We treated 88 locations of this lesion in 68 males. The clinical features were those of lower back pains, with or without radiation into the lower extremities, sensory loss and paresis of the limbs. There was a case of loss of urinary bladder and ano-rectal control. All lesions were confirmed through cauda-equinograms and treated under general anaesthesia in knee-chest position (MECCA position). The patients were followed up for 3-6 months post-operatively.

Results:

There were 88 locations in 68 males of 21-70 years of age, with 29 prolapses occurring during the age range 31-40 years, while 54 locations were on the left and 48 at L4/5. The procedures were well tolerated by all patients and there were no post-operative complications.

Conclusion:

This lesion in our series occurred mostly on the left, at the L4/5 level and peaked at 31-40 years age range. The predictability of occurrence of this disease, using side, level and age is still not feasible in males from our series.

Dystrophin and utrophin "double knockout" dystrophic mice exhibit a spectrum of degenerative musculoskeletal abnormalities

Duchenne muscular dystrophy (DMD) is a degenerative muscle disorder characterized by the lack of dystrophin expression at the sarcolemma of muscle fibers. In addition, DMD patients acquire osteopenia, fragility fractures, and scoliosis indicating that a deficiency in skeletal homeostasis coexists but little is known about the effects of DMD on bone and other connective tissues within the musculoskeletal system. Recent evidence has emerged implicating adult stem cell dysfunction in DMD myopathogenesis. Given the common mesenchymal origin of muscle and bone, we sought to investigate bone and other musculoskeletal tissues in a DMD mouse model. Here, we report that dystrophin-utrophin double knockout (dko) mice exhibit a spectrum of degenerative changes, outside skeletal muscle, in bone, articular cartilage, and intervertebral discs, in addition to reduced lifespan, muscle degeneration, spinal deformity, and cardiomyopathy previously reported. We also report these mice to have a reduced capacity for bone healing and exhibit spontaneous heterotopic ossification in the hind limb muscles. Therefore, we propose the dko mouse as a model for premature musculoskeletal aging and posit that a similar phenomenon may occur in patients with DMD.

Lumbar spine intervertebral disc gene delivery: a pilot study in lewis rats

BACKGROUND

Basic research toward understanding and treating disc pathology in the spine has utilized numerous animal models, with delivery of small molecules, purified factors, and genes of interest. To date, gene delivery to the rat lumbar spine has only been described utilizing genetically programmed cells in a matrix which has required partial disc excision, and expected limitation of treatment diffusion into the disc.

PURPOSE

This study was designed to develop and describe a surgical technique for lumbar spine exposure and disc space preparation, and use of a matrix-free method for gene delivery.

METHODS

Naïve or genetically programmed isogeneic bone marrow stromal cells were surgically delivered to adolescent male Lewis rat lumbar discs, and utilizing quantitative biochemical and qualitative immunohistological assessments, the implanted cells were detected 3 days post-procedure.

RESULTS

Statistically significant differences were noted for recovery of the β-galactosidase marker gene comparing delivery of naïve or labeled cells (10(5) cells per disc) from the site of implantation, and between delivery of 10(5) or 10(6) labeled cells per disc at the site of implantation and the adjacent vertebral body. Immunohistology confirmed that the β-galactosidase marker was detected in the adjacent vertebra bone in the zone of surgical implantation.

CONCLUSIONS

The model requires further testing in larger cohorts and with biologically active genes of interest, but the observations from the pilot experiments are very encouraging that this will be a useful comparative model for basic spine research involving gene or cell delivery, or other locally delivered therapies to the intervertebral disc or adjacent vertebral bodies in rats.

Surgically treated symptomatic prolapsed lumbar and sacral intervertebral discs in females: a comparative study of incidence and causative factors and treatment

Background and Objective:

There are various postulated possible causes of surgically symptomatic prolapsed intervertebral discs in the lumbar and sacral regions. They may be acting singularly or collectively. Yet, these factors, which could vary in different environments, have not been satisfactorily confirmed. The intention of this study is to share the experience of the author in the occurrence, possible causative factors, and treatment of surgically symptomatic prolapsed lumbar and sacral intervertebral discs in females, and to compare this experience in Switzerland, Nigeria, and Jamaica using surgery records for a period of over 39 years.

Materials and Methods:

Records of these cases were examined and analyzed with the intent of comparing the frequency of occurrence and possible causative factors of this lesion in some countries.

Results:

There were 60 locations in 51 patients in Basel (Caucasian population only), 4 locations in 1 patient in Imo and Ebonyi States (African population only), and none in Jamaica (mixed population). The patients’ ages ranged from 19 to 71 years in Switzerland, and the only patient in Nigeria was 49 years old.

Conclusion:

The study revealed that surgically treated symptomatic prolapsed lumbar and sacral intervertebral discs in females occurred more in Basel, Switzerland, than in Imo and Ebonyi States of Nigeria and none occurred in Jamaica, West Indies. Racial differences, certain sporting/recreational activities, smoking, and type of profession could have contributed to the development of this disease.

OARSI-FDA initiative: defining the disease state of osteoarthritis

OBJECTIVE

To respond to a pre-specified set of questions posed by the United States Food and Drug Administration (FDA) on defining the disease state to inform the clinical development of drugs, biological products, and medical devices for the prevention and treatment of osteoarthritis (OA).

METHODS

An Osteoarthritis Research Society International (OARSI) Disease State working group was established, comprised of representatives from academia and industry. The Working Group met in person and by teleconference on several occasions from the Spring of 2008 through the Autumn of 2009 to develop consensus-based, evidence-informed responses to these questions. A report was presented at a public forum in December 2009 and accepted by the OARSI Board of Directors in the Summer of 2010.

RESULTS

An operational definition of OA was developed incorporating current understanding of the condition. The structural changes that characterize OA at the joint level were distinguished from the patients' experience of OA as the 'disease' and 'illness', respectively. Recommendations were made regarding the evaluation of both in future OA clinical trials. The current poor understanding of the phenotypes that characterize OA was identified as an important area for future research.

CONCLUSIONS

The design and conduct of clinical trials for new OA treatments should address the heterogeneity of the disease, treatment-associated structural changes in target joints and patient-reported outcomes.

Enhancement of matrix production and cell proliferation in human annulus cells under bioreactor culture

Tissue engineering is a promising approach for treatment of disc degeneration. Herein, we evaluated effects of rotating bioreactor culture on the extracellular matrix production and proliferation of human annulus fibrosus (AF) cells. AF cells were embedded into alginate beads, and then cultured up to 3 weeks in a rotating wall vessel bioreactor or a static vessel. By real-time reverse transcription-polymerase chain reaction, expression of aggrecan, collagen type I and type II, and collagen prolyl 4-hydroxylase II was remarkably elevated, whereas expression of matrix metalloproteinase 3 and a disintegrin and metalloproteinase with thrombospondin motifs 5 was significantly decreased under bioreactor. Biochemical analysis revealed that the levels of the whole cell-associated proteoglycan and collagen were approximately five- and twofolds in rotating bioreactor, respectively, compared to those in static culture. Moreover, AF cell proliferation was augmented in rotating bioreactor. DNA contents were threefolds higher in rotating bioreactor than that in static culture. Expression of the proliferating cell nuclear antigen was robustly enhanced in rotating bioreactor as early as 1 week. Our findings suggested that rotating bioreactor culture would be an effective technique for expansion of human annulus cells for tissue engineering driven treatment of disc degeneration.

Endplate degeneration may be the origination of the vacuum phenomenon in intervertebral discs

The intravertebral vacuum phenomenon (VP) is usually associated with degenerative disc disease, which could be related to the low back pain. Various theories related to the pathogenesis of VP have been proposed, but these theories have not been critically examined and remain hypothetical. In this article, we review the possible role of endplate degeneration in the pathogenesis of VP, and discuss several pathways possibly linked to them. Due to the endplate calcification and activated cytokines, the transport pathway of the nutrition for the intervertebral disc was blocked, resulting in the metabolic unbalance and decrease of the synthesis of matrix structural proteins. It could promote the matrix decomposition, causing the decrease of the quantity of matrix and the changes of stress distribution in intervertebral disc. As a result, the structure of intervertebral discs became increasingly unstable. While compression happened, the intravertebral cleft could occur and be gradually filled with gas, which may cause low back pain and aggravate the intervertebral discs degeneration. As outlined above, we hypothesize that endplate degeneration might be the origination of the vacuum phenomenon.

Effect of Nell-1 delivery on chondrocyte proliferation and cartilaginous extracellular matrix deposition

Cartilage tissue engineering using chondrogenic growth factors is an attractive strategy to promote cartilage repair. Bone morphogenetic proteins have been widely studied for their application in cartilage repair. However, functional heterogeneity of bone morphogenetic proteins and unpredictable effects such as cyst formation may limit their therapeutic use. Thus, the use of alternative growth factors with greater osteochondral specificity may be advantageous for cartilage regeneration. Nel-like molecule-1 (Nell-1; Nel is a protein strongly expressed in neural tissue encoding epidermal growth factor-like domain) is a novel growth factor believed to specifically target cells committed to the osteochondral lineage. Mutation of the Nell-1 gene has been shown to disrupt normal cartilage growth and development in rodents. This study investigates the chondrogenic potential of recombinant human Nell-1 protein in a three-dimensional alginate hydrogel microenvironment containing rabbit chondrocytes. To provide controlled delivery and maximize biological efficiency, Nell-1 was incorporated in chitosan microparticles. Over 42 days of culture, chondrocyte proliferation and cluster formation was significantly enhanced by Nell-1 in a dose-dependent manner. Further, the clusters formed in the presence of Nell-1 contained more type II collagen and glycosaminoglycans than clusters formed within Nell-free control gels. These findings demonstrate the ability of Nell-1 to promote chondrocyte proliferation and deposition of cartilage-specific extracellular matrix materials.

p38 MAPK inhibition selectively mitigates inflammatory mediators and VEGF production in AF cells co-cultured with activated macrophage-like THP-1 cells

OBJECTIVES

Recent data have suggested that macrophages are involved in the pathogenesis of discogenic back pain and enhance the secretion of inflammatory mediators in co-cultured annulus fibrosus (AF) cells. The purpose of these studies is to determine the role of p38 mitogen-activated protein kinase (p38 MAPK) signaling in the interactions between macrophage and AF cells.

METHODS

Human AF cells were co-cultured with phorbol myristate acetate-stimulated macrophage-like THP-1 cells with and without p38 MAPK inhibition. Conditioned media from co-cultured cells were assayed for interleukin (IL)-6, IL-8, prostaglandin E2 (PGE2), PGF2alpha, and vascular endothelial growth factor (VEGF). Naïve and macrophage-exposed AF cell responses to 10ng/ml tumor necrosis factor-alpha (TNF-alpha) were compared using the same outcome measures.

RESULTS

IL-6, IL-8, PGE2, PGF2alpha, and VEGF were secreted in greater quantities by cells maintained in co-culture compared to macrophages or AF cells cultured alone. SB202190 blunted IL-6, PGE2, and PGF2alpha production in a dose-dependent manner in co-culture. However, it did not suppress IL-8 and VEGF production. TNF-alpha-stimulated AF cell inflammatory mediators were up-regulated by macrophage exposure. SB202190 successfully suppressed IL-6, IL-8, PGE2, and PGF2alpha secretion in macrophage-exposed AF cells in response to TNF-alpha.

CONCLUSIONS

Annular injury can result in macrophage infiltration, and this can cause enhanced inflammatory mediator and VEGF production by AF cells. The p38 MAPK pathway signals are responsible for much of IL-6 and PG secretion from AF cells with macrophage-like cells, suggesting that blockade of this signal may serve as a therapeutic approach to discogenic pain.