Neuropathic pain post spinal cord injury part 1: systematic review of physical and behavioral treatment

The effect of neuropathic pain treatments on pain interference following spinal cord injury: A systematic review

CONTEXT

Neuropathic pain is a common and debilitating condition following SCI. While treatments for neuropathic pain intensity have been reviewed, the impact on pain interference has not been summarized.

OBJECTIVE

To systematically review the effect of neuropathic pain interventions on pain interference in individuals with spinal cord injury.

METHODS

This systematic review included randomized controlled trials and quasi-experimental (non-randomized) studies which assessed the impact of an intervention on pain interference in individuals with spinal cord injury and neuropathic pain. Articles were identified by searching MEDLINE (1996 to April 11, 2022), EMBASE (1996 to April 11, 2022), PsycInfo (1987 to April, week 2, 2022). Studies were assessed for methodologic quality using a modified GRADE approach and were given quality of evidence (QOE) scores on a 4-point scale ranging from very low to high.

RESULTS

Twenty studies met the inclusion criteria. These studies fell into the following categories: anticonvulsants (n = 2), antidepressants (n = 1), analgesics (n = 1), antispasmodics (n = 1), acupuncture (n = 2), transcranial direct current stimulation (n = 1), active cranial electrotherapy stimulation (n = 2), transcutaneous electrical nerve stimulation (n = 2), repetitive transcranial magnetic stimulation (n = 1), functional electrical stimulation (n = 1), meditation and imagery (n = 1), self-hypnosis and biofeedback (n = 1), and interdisciplinary pain programs (n = 4).

CONCLUSION

When considering studies of moderate to high quality, pregabalin, gabapentin, intrathecal baclofen, transcranial direct current stimulation, and transcutaneous electrical nerve stimulation (in 1 of 2 studies) were shown to have beneficial effects on pain interference. However, due to the low number of high-quality studies further research is required to confirm the efficacy of these interventions prior to recommending their use to reduce pain interference.

Effect of virtual running with exercise on functionality in pre-frail and frail elderly people: randomized clinical trial

BACKGROUND

Virtual mirror therapies could increase the results of exercise, since the mirror neuron system produces an activation of motor execution cortical areas by observing actions performed by others. In this way, pre-frail and frail people could use this system to reach an exercise capacity threshold and obtain health benefits.

AIM

The aim of this study is to evaluate the effects of a virtual running (VR) treatment combined with specific physical gait exercise (PE) compared to placebo VR treatment combined with PE on functionality, pain, and muscular tone in pre-frail and frail older persons.

METHODS

A single blinded, two-arm, randomised controlled trial design was employed. Thirty-eight participants were divided into two intervention arms: Experimental Intervention (EI) group, in which VR and gait-specific physical exercises were administered and Control Intervention (CI) group, in which a placebo virtual gait and the same exercise programme was administered. Functionality, pain, and tone were assessed.

RESULTS

EI group improved in aerobic capacity, functional lower-limb strength, reaction time, and pain, while CI group remained the same. Regarding static balance and muscle tone, no differences were found for either group. Further analysis is needed to asses VR effectiveness for improving gait, stand-up and sit-down performance and velocity.

CONCLUSIONS

Virtual running therapy appears to enhance capacities related with voluntary movements (i.e., aerobic capacity, functional lower-limb strength, and reaction time) and reduce pain.

Potential mechanisms of acupuncture for neuropathic pain based on somatosensory system

Neuropathic pain, caused by a lesion or disease of the somatosensory system, is common and distressing. In view of the high human and economic burden, more effective treatment strategies were urgently needed. Acupuncture has been increasingly used as an adjuvant or complementary therapy for neuropathic pain. Although the therapeutic effects of acupuncture have been demonstrated in various high-quality randomized controlled trials, there is significant heterogeneity in the underlying mechanisms. This review aimed to summarize the potential mechanisms of acupuncture on neuropathic pain based on the somatosensory system, and guided for future both foundational and clinical studies. Here, we argued that acupuncture may have the potential to inhibit neuronal activity caused by neuropathic pain, through reducing the activation of pain-related ion channels and suppressing glial cells (including microglia and astrocytes) to release inflammatory cytokines, chemokines, amongst others. Meanwhile, acupuncture as a non-pharmacologic treatment, may have potential to activate descending pain control system via increasing the level of spinal or brain 5-hydroxytryptamine (5-HT), norepinephrine (NE), and opioid peptides. And the types of endogenously opioid peptides was influenced by electroacupuncture-frequency. The cumulative evidence demonstrated that acupuncture provided an alternative or adjunctive therapy for neuropathic pain.

Should Non-Pharmacological and Non-Surgical Interventions be Used to Manage Neuropathic Pain in Adults With Spinal Cord Injury? - A Systematic Review

Spinal Cord Injury (SCI) results in a permanent or temporary alteration of the motor, sensory and/or autonomic functions, frequently leading to neuropathic pain. To deal with this comorbidity, several non-pharmacological and non-surgical (NP-NS) interventions have been developed. However, their efficacy is still uncertain. The aim of this study was to systematically synthetize the available evidence assessing the efficacy of NP-NS interventions for treating neuropathic pain in people with SCI. Thus, an electronic search was conducted in five databases (Pubmed, Scopus, Cochrane Central, Web of Science and EBSCO) and trials registry databases, in addition to a manual search strategy to retrieve additional records. The review included randomized controlled trials with adults with SCI, in any stage of the condition. Data on the efficacy of the interventions was narratively synthetized. Once the research was completed, of 4853 identified references, 24 were included with a total of 653 participants with SCI and neuropathic pain, mostly male and with paraplegia. These studies investigated the effect of 13 types of NP-NS interventions with different protocols and methodological limitations. Seven different assessment scales were analyzed, with neuropathic pain being the primary outcome in 21 studies. Such high heterogeneity impaired the conduction of meta-analysis for any of the interventions. Although promising results were found regarding analgesic effect of NP-NS on neuropathic pain in people with SCI, it is not yet possible to safely state that these interventions are in fact effective. Further studies with homogeneous protocols and methodological quality are still needed. PERSPECTIVE: This article presents a review of existing studies on the effectiveness of NP-NS interventions in neuropathic pain in SCI. This synthesis could potentially alert and motivate clinicians to develop studies on this topic, so that interventions can be objectively evaluated and recommendations for an evidence-based practice be created.

Pilot clinical trial of a clinical meditation and imagery intervention for chronic pain after spinal cord injury

OBJECTIVE

To assess the feasibility and potential benefits of clinical meditation and imagery (CMI) for people with chronic spinal cord injury (SCI) and chronic pain.

DESIGN

Pilot randomized, controlled trial.

SETTING

Outpatients with SCI in the United States.

PARTICIPANTS

24 adults with chronic SCI (>1 year) and a >3 month history of pain rated ≥4/10 on average over the last week.

INTERVENTIONS

4-week program of once-weekly 2-hour group classes, offered in-person and online. CMI group participants were taught mindfulness, mantra meditation, and guided imagery practices. Control group participants received education on topics related to health and function after SCI.

OUTCOME MEASURES

Pain interference (primary outcome), pain cognitions, pain intensity/unpleasantness, depressive symptomology, perceived stress.

RESULTS

Pain interference decreased to a greater extent in the control group at both Day 42 and Day 70, with a large effect size (d > 1.0). Several secondary outcome measures showed changes consistent with more favorable outcomes in the CMI group at both Day 42 and Day 70, with a large effect size d > 0.80, including worst pain intensity over the last week, depressive symptomology, belief in pain as a sign of harm and perceived control over pain. Perceived stress improved to a greater extent in the control group (d = 1.16 at Day 42, d = .20 at Day 70).

CONCLUSION

CMI is feasible and acceptable to implement with people with SCI and chronic pain. Further study is warranted to assess potential benefits for pain-related outcomes.

Effects of repeated transcranial magnetic stimulation in the dorsolateral prefrontal cortex versus motor cortex in patients with neuropathic pain after spinal cord injury: a study protocol

INTRODUCTION

Neuropathic pain is one of the common complications of spinal cord injuries (SCI), which will slow down the recovery process and result in lower quality of life. Previous studies have shown that repeated transcranial magnetic stimulation (rTMS) of the motor cortex (M1) can reduce the average pain and the most severe pain of neuropathic pain after SCI. The dorsolateral prefrontal cortex (DLPFC) area is a common target of rTMS. Recently, a few studies found that rTMS of DLPFC may relieve the neuropathic pain of SCI. Compared with the M1 area, the efficacy of rTMS treatment in the DLPFC area in improving neuropathic pain and pain-related symptoms in patients with SCI is still unclear. Therefore, our study aims to evaluate the non-inferiority of rTMS in the DLPFC vs M1 in patients with neuropathic pain after SCI, in order to provide more options for rTMS in treating neuropathic pain after SCI.

METHODS AND ANALYSIS

We will recruit 50 subjects with neuropathic pain after SCI. They will be randomly assigned to the DLPFC- rTMS and M1-rTMS groups and be treated with rTMS for 4 weeks. Except for the different stimulation sites, the rTMS treatment programmes of the two groups are the same: 10 Hz, 1250 pulses, 115% intensity threshold, once a day, five times a week for 4 weeks. VAS, simplified McGill Pain Questionnaire, Spinal Cord Injury Pain Date Set, Pittsburgh Sleep Quality Index and Hamilton Anxiety Scale will be evaluated at baseline, second week of treatment, fourth week of treatment and 4 weeks after the end of treatment. And VAS change will be calculated.

ETHICS AND DISSEMINATION

The Ethics Committee of the Affiliated Hospital of Southwest Medical University has approved this trial, which is numbered KY2020041. Written informed consent will be provided to all participants after verification of the eligibility criteria. The results of the study will be published in peer-reviewed publications.

TRIAL REGISTRATION NUMBER

ChiCTR2000032362.

Evidence Mapping Based on Systematic Reviews of Repetitive Transcranial Magnetic Stimulation on the Motor Cortex for Neuropathic Pain

BACKGROUND AND OBJECTIVE

There is vast published literature proposing repetitive transcranial magnetic stimulation (rTMS) technology on the motor cortex (M1) for the treatment of neuropathic pain (NP). Systematic reviews (SRs) focus on a specific problem and do not provide a comprehensive overview of a research area. This study aimed to summarize and analyze the evidence of rTMS on the M1 for NP treatment through a new synthesis method called evidence mapping.

METHODS

Searches were conducted in PubMed, EMBASE, Epistemonikos, and The Cochrane Library to identify the studies that summarized the effectiveness of rTMS for NP. The study type was restricted to SRs with or without meta-analysis. All literature published before January 23, 2021, was included. Two reviewers independently screened the literature, assessed the methodological quality, and extracted the data. The methodological quality of the included SRs was assessed by using the A Measurement Tool to Assess Systematic Reviews (AMSTAR-2). Data were extracted following a defined population, intervention, comparison, and outcome (PICO) framework from primary studies that included SRs. The same PICO was categorized into PICOs according to interventions [frequency, number of sessions (short: 1-5 sessions, medium: 5-10 sessions, and long: >10 sessions)] and compared. The evidence map was presented in tables and a bubble plot.

RESULTS

A total of 38 SRs met the eligibility criteria. After duplicate primary studies were removed, these reviews included 70 primary studies that met the scope of evidence mapping. According to the AMSTAR-2 assessment, the quality of the included SRs was critically low. Of these studies, 34 SRs scored "critically low" in terms of methodological quality, 2 SR scored "low," 1 SR scored "moderate," and 1 SR scored "high."

CONCLUSION

Evidence mapping is a useful methodology to provide a comprehensive and reliable overview of studies on rTMS for NP. Evidence mapping also shows that further investigations are necessary to highlight the optimal stimulation protocols and standardize all parameters to fill the evidence gaps of rTMS. Given that the methodological quality of most included SRs was "critically low," further investigations are advised to improve the methodological quality and the reporting process of SRs.

Developing Peri-Operative Rehabilitation in Degenerative Cervical Myelopathy [AO Spine RECODE-DCM Research Priority Number 6]: An Unexplored Opportunity?

STUDY DESIGN

Narrative review.

OBJECTIVE

Degenerative cervical myelopathy is one of the most frequent impairments of the spinal cord encountered internationally in adults. Currently, surgical decompression is the recommended treatment for people with DCM (PwCM) presenting with moderate to severe symptoms or neurological deficits. However, despite surgical intervention, not all patients make a complete recovery due to the irreversible tissue damage within the spinal cord. The objective of this review is to describe the state and gaps in the current literature on rehabilitation for PwCM and possible innovative rehabilitation strategies.

METHODS

Literature search.

RESULTS

In other neurological disorders such as stroke and acute traumatic spinal cord injury (SCI), timely and strategic rehabilitation has been shown to be indispensable for maximizing functional outcomes, and it is imperative that appropriate perioperative rehabilitative interventions accompany surgical approaches in order to enable the best outcomes. In this review, the current state of knowledge regarding rehabilitation for PwCM is described. Additionally, various therapies that have shown to improve outcomes in comparable neurological conditions such as stroke and SCI which may be translated to DCM will be reviewed.

CONCLUSIONS

We conclude that locomotor training and arm/hand therapy may benefit PwCM. Further, we conclude that body weight support, robotic assistance, and virtual/augmented reality therapies may be beneficial therapeutic analogs to locomotor and hand therapies.

Does TENS Reduce the Intensity of Acute and Chronic Pain? A Comprehensive Appraisal of the Characteristics and Outcomes of 169 Reviews and 49 Meta-Analyses

Background and Objectives: Uncertainty about the clinical efficacy of transcutaneous electric nerve stimulation (TENS) to alleviate pain spans half a century. There has been no attempt to synthesise the entire body of systematic review evidence. The aim of this comprehensive review was to critically appraise the characteristics and outcomes of systematic reviews evaluating the clinical efficacy of TENS for any type of acute and chronic pain in adults. Materials and Methods: We searched electronic databases for full reports of systematic reviews of studies, overviews of systematic reviews, and hybrid reviews that evaluated the efficacy of TENS for any type of clinical pain in adults. We screened reports against eligibility criteria and extracted data related to the characteristics and outcomes of the review, including effect size estimates. We conducted a descriptive analysis of extracted data. Results: We included 169 reviews consisting of eight overviews, seven hybrid reviews and 154 systematic reviews with 49 meta-analyses. A tally of authors' conclusions found a tendency toward benefits from TENS in 69/169 reviews, no benefits in 13/169 reviews, and inconclusive evidence in 87/169 reviews. Only three meta-analyses pooled sufficient data to have confidence in the effect size estimate (i.e., pooled analysis of >500 events). Lower pain intensity was found during TENS compared with control for chronic musculoskeletal pain and labour pain, and lower analgesic consumption was found post-surgery during TENS. The appraisal revealed repeated shortcomings in RCTs that have hindered confident judgements about efficacy, resulting in stagnation of evidence. Conclusions: Our appraisal reveals examples of meta-analyses with 'sufficient data' demonstrating benefit. There were no examples of meta-analyses with 'sufficient data' demonstrating no benefit. Therefore, we recommend that TENS should be considered as a treatment option. The considerable quantity of reviews with 'insufficient data' and meaningless findings have clouded the issue of efficacy. We offer solutions to these issues going forward.

Tissue bridges predict neuropathic pain emergence after spinal cord injury

OBJECTIVE

To assess associations between preserved spinal cord tissue quantified by the width of ventral and dorsal tissue bridges and neuropathic pain development after spinal cord injury.

METHODS

This retrospective longitudinal study includes 44 patients (35 men; mean (SD) age, 50.05 (18.88) years) with subacute (ie, 1 month) spinal cord injury (25 patients with neuropathic pain, 19 pain-free patients) and neuroimaging data who had a follow-up clinical assessment at 12 months. Widths of tissue bridges were calculated from midsagittal T2-weighted images and compared across groups. Regression analyses were used to identify relationships between these neuroimaging measures and previously assessed pain intensity and pin-prick score.

RESULTS

Pin-prick score of the 25 patients with neuropathic pain increased from 1 to 12 months (Δmean=10.08, 95% CI 2.66 to 17.50, p=0.010), while it stayed similar in pain-free patients (Δmean=2.74, 95% CI -7.36 to 12.84, p=0.576). They also had larger ventral tissue bridges (Δmedian=0.80, 95% CI 0.20 to 1.71, p=0.008) at 1 month when compared with pain-free patients. Conditional inference tree analysis revealed that ventral tissue bridges' width (≤2.1 or >2.1 mm) at 1 month is the strongest predictor for 12 months neuropathic pain intensity (1.90±2.26 and 3.83±1.19, p=0.042) and 12 months pin-prick score (63.84±28.26 and 92.67±19.43, p=0.025).

INTERPRETATION

Larger width of ventral tissue bridges-a proxy for spinothalamic tract function-at 1 month post-spinal cord injury is associated with the emergence and maintenance of neuropathic pain and increased pin-prick sensation. Spared ventral tissue bridges could serve as neuroimaging biomarkers of neuropathic pain and might be used for prediction and monitoring of pain outcomes and stratification of patients in interventional trials.

Management of pain in individuals with spinal cord injury: Guideline of the German-Speaking Medical Society for Spinal Cord Injury

Introduction: Pain is a prominent complication in spinal cord injury (SCI). It can either occur as a direct or as an indirect consequence of SCI and it often heavily influences the quality of life of affected individuals. In SCI, nociceptive and neuropathic pain can equally emerge at the same time above or below the level of injury. Thus, classification and grading of pain is frequently difficult. Effective treatment of SCI-related pain in general and of neuropathic pain in particular is challenging. Current treatment options are sparse and their evidence is considered to be limited. Considering these aspects, a clinical practice guideline was developed as basis for an optimized, comprehensive and standardized pain management in SCI-related pain.

Methods: The German-Speaking Medical Society for Spinal Cord Injury (Deutschsprachige Medizinische Gesellschaft für Paraplegiologie – DMGP) developed a clinical practice guideline that received consensus from seven further German-speaking medical societies and one patient organization. The evidence base from clinical trials and meta-analyses was summarized and subjected to a structured consensus-process in accordance with the regulations of the Association of Scientific Medical Societies in Germany (AWMF) and the methodological requirements of the “German instrument for methodological guideline appraisal”.

Results: This consensus-based guideline (S2k classification according to the AWMF guidance manual and rules) resulted in seven on-topic statements and 17 specific recommendations relevant to the classification, assessment and therapy of pain directly or indirectly caused by SCI. Recommended therapeutic approaches comprise pharmacological (e.g. nonsteroidal anti-inflammatory drugs or anticonvulsants) and non-pharmacological (e.g. physical activity or psychotherapeutic techniques) strategies for both nociceptive and neuropathic pain.

Discussion: Assessment of SCI-related pain is standardized and respective methods in terms of examination, classification and grading of pain are already in use and validated in German language. In contrast, valid, evidence-based and efficient therapeutic options are limited and ask for further clinical studies, ideally randomized controlled trials and meta-analyses.

Pain profiles in a community dwelling population following spinal cord injury: a national survey

CONTEXT

While as many as 60% of patients with spinal cord injury (SCI) develop chronic pain, limited data currently exists on the prevalence and profile of pain post-SCI in community dwelling populations.

STUDY DESIGN

A cross-sectional population survey.

SETTING

Primary care.

PARTICIPANTS

Community dwelling adults with SCI.

METHODS

Following ethical approval members registered to a national SCI database (n=1,574) were surveyed. The survey included demographic and SCI characteristics items, the International Spinal Cord Injury Pain Basic Data Set (version 1) the Douleur Neuropathique 4 questionnaire (interview) and questions relating to health care utilisation. Data were entered into the Statistical Package for the Social Sciences (version 20) Significance was set P < 0.05 for between group comparisons.

RESULTS

In total 643 (41%) surveys were returned with 458 (71%) respondents experiencing pain in the previous week. Neuropathic pain (NP) was indicated in 236 (37%) of responses and nociceptive pain in 206 (32%) Common treatments for pain included medications n=347 (76%) massage n=133 (29%) and heat n=115 (25%). Respondents with NP reported higher pain intensities and increased healthcare service utilisation (P= < 0.001) when compared to those with nociceptive pain presentations. A higher proportion of females than males reported pain (P = 0.003) and NP (P = 0.001) and those unemployed presented with greater NP profiles compared with those in education or employment (P = 0.006).

CONCLUSION

Pain, in particular NP post SCI interferes with daily life, increases health service utilisation and remains refractory to current management strategies. Increased availability of multi-disciplinary pain management and further research into management strategies is warranted.

Spinal Cord Injury: How Could Acupuncture Help?

Spinal cord injury (SCI) is one of the most common causes of death and disability worldwide, and it can result in both permanent disability and serial complications in patients. Research shows that patients with SCI complications are often interested in acupuncture for symptomatic relief. Therefore, the issue of physicians advising their patients regarding the use of acupuncture to alleviate SCI complications becomes pertinent. We review and summarize two types of relevant publications: (1) literature concerning acupuncture for SCI and its complications and (2) underlying mechanisms of acupuncture therapy for SCI. Clinical trials and reviews have suggested that acupuncture effectively manages a range of post-SCI complications, including motor and sensory dysfunction, pain, neurogenic bowel and bladder, pressure ulcers, spasticity, and osteoporosis. The effect of acupuncture on post-SCI orthostatic hypotension and sexual dysfunction remains unclear. Decreased oxidative stress, inhibition of inflammation and neuronal apoptosis, regulation of the expression and activity of endogenous biological mediators, and increased regenerative stem cell production are the possible mechanisms of acupuncture therapy for SCI. Although many limitations have been reported in previous studies, given the evidence for the efficacy of acupuncture, we recommend that physicians should support the use of acupuncture therapy for SCI complications.

Altered transcription of glutamatergic and glycinergic receptors in spinal cord dorsal horn following spinal cord transection is minimally affected by passive exercise of the hindlimbs

Gene expression is altered following a spinal transection (STx) in both motor and sensory systems. Exercise has been shown to influence gene expression in both systems post-STx. Gene expression alterations have also been shown in the dorsal root ganglia and nociceptive laminae of the spinal cord following either an incomplete spinal cord injury (SCI) or a contusive SCI. However, the effect of STx and exercise on gene expression in spinal cord laminae I-III has not fully been examined. Therefore, the purpose of this study was to determine whether gene expression in laminae I-III is altered following STx and determine whether superimposed passive exercise of the hindlimbs would influence gene expression post-STx in laminae I-III. Laser capture microdissection was used to selectively harvest laminae I-III of lumbar spinal cord sections, and quantitative RT-PCR was used to examine relative expression of 23 selected genes in samples collected from control, STx and STx plus exercise rats. We demonstrate that post-STx, gene expression for metabotropic glutamate receptors 1, 5 and 8 were up-regulated, whereas ionotropic glutamatergic receptor (Glur2) and glycinergic subunit GLRA1 expression was down-regulated. Daily exercise attenuated the down-regulation of Glur2 gene expression in laminae I-III. Our results demonstrate that in a STx model, gene expression is altered in laminae I-III and that although passive exercise influences gene expression in both the motor and sensory systems, it had a minimal effect on gene expression in laminae I-III post-STx.

Effect of Patient Education on Reducing Medication in Spinal Cord Injury Patients With Neuropathic Pain

Objective

To determine whether providing education about the disease pathophysiology and drug mechanisms and side effects, would be effective for reducing the use of pain medication while appropriately managing neurogenic pain in spinal cord injury (SCI) patients.

Methods

In this prospective study, 109 patients with an SCI and neuropathic pain, participated in an educational pain management program. This comprehensive program was specifically created, for patients with an SCI and neuropathic pain. It consisted of 6 sessions, including educational training, over a 6-week period.

Results

Of 109 patients, 79 (72.5%) initially took more than two types of pain medication, and this decreased to 36 (33.0%) after the educational pain management program was completed. The mean pain scale score and the number of pain medications decreased, compared to the baseline values. Compared to the non-response group, the response group had a shorter duration of pain onset (p=0.004), and a higher initial number of different medications (p<0.001) and certain types of medications.

Conclusion

This study results imply that an educational pain management program, can be a valuable complement to the treatment of spinal cord injured patients with neuropathic pain. Early intervention is important, to prevent patients from developing chronic SCI-related pain.

Gene expression profiles reveal key pathways and genes associated with neuropathic pain in patients with spinal cord injury

Previous gene expression profiling studies of neuropathic pain (NP) following spinal cord injury (SCI) have predominantly been performed in animal models. The present study aimed to investigate gene alterations in patients with spinal cord injury and to further examine the mechanisms underlying NP following SCI. The GSE69901 gene expression profile was downloaded from the public Gene Expression Omnibus database. Samples of peripheral blood mononuclear cells (PBMCs) derived from 12 patients with intractable NP and 13 control patients without pain were analyzed to identify the differentially expressed genes (DEGs), followed by functional enrichment analysis and protein‑protein interaction (PPI) network construction. In addition, a transcriptional regulation network was constructed and functional gene clustering was performed. A total of 70 upregulated and 61 downregulated DEGs were identified in the PBMC samples from patients with NP. The upregulated and downregulated genes were significantly involved in different Gene Ontology terms and pathways, including focal adhesion, T cell receptor signaling pathway and mitochondrial function. Glycogen synthase kinase 3 β (GSK3B) was identified as a hub protein in the PPI network. In addition, ornithine decarboxylase 1 (ODC1) and ornithine aminotransferase (OAT) were regulated by additional transcription factors in the regulation network. GSK3B, OAT and ODC1 were significantly enriched in two functional gene clusters, the function of mitochondrial membrane and DNA binding. Focal adhesion and the T cell receptor signaling pathway may be significantly linked with NP, and GSK3B, OAT and ODC1 may be potential targets for the treatment of NP.

The use of intraoperative triggered electromyography to detect misplaced pedicle screws: a systematic review and meta-analysis

OBJECT

Insertion of instruments or implants into the spine carries a risk for injury to neural tissue. Triggered electromyography (tEMG) is an intraoperative neuromonitoring technique that involves electrical stimulation of a tool or screw and subsequent measurement of muscle action potentials from myotomes innervated by nerve roots near the stimulated instrument. The authors of this study sought to determine the ability of tEMG to detect misplaced pedicle screws (PSs).

METHODS

The authors searched the US National Library of Medicine, the Web of Science Core Collection database, and the Cochrane Central Register of Controlled Trials for PS studies. A meta-analysis of these studies was performed on a per-screw basis to determine the ability of tEMG to detect misplaced PSs. Sensitivity, specificity, and receiver operating characteristic (ROC) area under the curve (AUC) were calculated overall and in subgroups.

RESULTS

Twenty-six studies were included in the systematic review. The authors analyzed 18 studies in which tEMG was used during PS placement in the meta-analysis, representing data from 2932 patients and 15,065 screws. The overall sensitivity of tEMG for detecting misplaced PSs was 0.78, and the specificity was 0.94. The overall ROC AUC was 0.96. A tEMG current threshold of 10–12 mA (ROC AUC 0.99) and a pulse duration of 300 µsec (ROC AUC 0.97) provided the most accurate testing parameters for detecting misplaced screws. Screws most accurately conducted EMG signals (ROC AUC 0.98).

CONCLUSIONS

Triggered electromyography has very high specificity but only fair sensitivity for detecting malpositioned PSs.