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Medicina (Kaunas, Lithuania) Jul 2023Chronic non-specific low back pain (CNSLBP) is defined as back pain that lasts longer than 12 weeks. Capacitive and resistive electric transfer (TECAR) therapy utilizes... (Randomized Controlled Trial)
Randomized Controlled Trial
Short-Term Effects of Manual Therapy plus Capacitive and Resistive Electric Transfer Therapy in Individuals with Chronic Non-Specific Low Back Pain: A Randomized Clinical Trial Study.
Chronic non-specific low back pain (CNSLBP) is defined as back pain that lasts longer than 12 weeks. Capacitive and resistive electric transfer (TECAR) therapy utilizes radiant energy to generate endogenous heat and is widely used for the treatment of chronic musculoskeletal pain. The aim of this study was to investigate the efficacy of manual therapy (MT) program combined with TECAR therapy in individuals with CNSLBP. Sixty adults with CNSLBP were randomly divided equally into three groups. The first group followed an MT protocol in the lumbar region (MT group), the second group followed the same MT protocol combined with TECAR therapy (MT + TECAR group) using a conventional capacitive electrode as well as a special resistive electrode bracelet, and the third group (control group) received no treatment. Both intervention programs included six treatments over two weeks. Pain in the last 24 h with the Numeric Pain Rating Scale (NPRS), functional ability with the Roland-Morris Disability Questionnaire (RMDQ), pressure pain threshold (PPT) in the lumbar region with pressure algometry, and mobility of the lumbo-pelvic region through fingertip-to-floor distance (FFD) test were evaluated before and after the intervention period with a one-month follow-up. Analysis of variance with repeated measures was applied. In the NPRS score, both intervention groups showed statistically significant differences compared to the control group both during the second week and the one-month follow-up ( < 0.001). Between-group differences were also noticed between the two intervention groups in the second week ( < 0.05). Differences in the RMDQ score were detected between the intervention groups and the control group in the second week and at the one-month follow-up ( < 0.001), while differences between the two intervention groups were only detected at the one-month follow-up ( < 0.001). Regarding the PPT values, differences were found mainly between the MT + TECAR group and the control group and between the MT + TECAR group and the MT group ( < 0.05), with the MT + TECAR group in most cases showing the greatest improvement compared to the other two groups, which remained statistically significant at the one-month follow-up ( < 0.05). Finally, both intervention groups improved the mobility of the lumbo-pelvic region at both time points compared to the control group without, however, statistically significant differences between them ( > 0.05). The application of an MT protocol with TECAR therapy appeared more effective than conventional MT as well as compared to the control group in reducing pain and disability and improving PPT in individuals with CNSLBP. No further improvement was noted in the mobility of the lumbo-pelvic region by adding TECAR to the MT intervention.
Topics: Adult; Humans; Low Back Pain; Musculoskeletal Manipulations; Chronic Pain; Lumbosacral Region; Activities of Daily Living; Treatment Outcome
PubMed: 37512085
DOI: 10.3390/medicina59071275 -
The Journal of Headache and Pain Aug 2023There is increasing evidence from human and animal studies that cortical spreading depression (CSD) is the neurophysiological correlate of migraine aura and a trigger of...
BACKGROUND
There is increasing evidence from human and animal studies that cortical spreading depression (CSD) is the neurophysiological correlate of migraine aura and a trigger of migraine pain mechanisms. The mechanisms of initiation of CSD in the brain of migraineurs remain unknown, and the mechanisms of initiation of experimentally induced CSD in normally metabolizing brain tissue remain incompletely understood and controversial. Here, we investigated the mechanisms of CSD initiation by focal application of KCl in mouse cerebral cortex slices.
METHODS
High KCl puffs of increasing duration up to the threshold duration eliciting a CSD were applied on layer 2/3 whilst the membrane potential of a pyramidal neuron located very close to the site of KCl application and the intrinsic optic signal were simultaneously recorded. This was done before and after the application of a specific blocker of either NMDA or AMPA glutamate receptors (NMDARs, AMPARs) or voltage-gated Ca (Ca) channels. If the drug blocked CSD, stimuli up to 12-15 times the threshold were applied.
RESULTS
Blocking either NMDARs with MK-801 or Ca channels with Ni completely inhibited CSD initiation by both CSD threshold and largely suprathreshold KCl stimuli. Inhibiting AMPARs with NBQX was without effect on the CSD threshold and velocity. Analysis of the CSD subthreshold and threshold neuronal depolarizations in control conditions and in the presence of MK-801 or Ni revealed that the mechanism underlying ignition of CSD by a threshold stimulus (and not by a just subthreshold stimulus) is the Ca-dependent activation of a threshold level of NMDARs (and/or of channels whose opening depends on the latter). The delay of several seconds with which this occurs underlies the delay of CSD initiation relative to the rapid neuronal depolarization produced by KCl.
CONCLUSIONS
Both NMDARs and Ca channels are necessary for CSD initiation, which is not determined by the extracellular K or neuronal depolarization levels per se, but requires the Ca-dependent activation of a threshold level of NMDARs. This occurs with a delay of several seconds relative to the rapid depolarization produced by the KCl stimulus. Our data give insights into potential mechanisms of CSD initiation in migraine.
Topics: Mice; Animals; Humans; Cortical Spreading Depression; Dizocilpine Maleate; Migraine Disorders; Receptors, N-Methyl-D-Aspartate; Migraine with Aura
PubMed: 37553625
DOI: 10.1186/s10194-023-01643-9 -
BioRxiv : the Preprint Server For... Aug 2023Women develop chronic pain during their reproductive years more often than men, and estrogen and progesterone regulate this susceptibility. We tested whether brain...
Women develop chronic pain during their reproductive years more often than men, and estrogen and progesterone regulate this susceptibility. We tested whether brain progesterone receptor (PR) signaling regulates pain susceptibility. During the estrous cycle, animals were more sensitive to pain during the estrus stage than in the diestrus stage, suggesting a role for reproductive hormones, estrogen, and progesterone. We measured the pain threshold daily for four days in ovariectomized, estrogen-primed animals treated with progesterone. The pain threshold was lower 2 days later and stayed that way for the duration of the testing. A specific progesterone-receptor (PR) agonist, segesterone, promoted pain, and mice lacking PR in the brain (PRKO) did not experience lowered pain threshold when treated with progesterone or segesterone. PR activation increased the cold sensitivity but did not affect the heat sensitivity and had a small effect on light sensitivity. Finally, we evaluated whether PR activation altered experimental migraine. Segesterone and nitroglycerin (NTG) when administered sequentially, reduced pain threshold but not separately. These studies have uncovered a pain-regulating function of PRs. Targeting PRs may provide a novel therapeutic avenue to treat chronic pain in women.
PubMed: 37609239
DOI: 10.1101/2023.08.04.552037 -
International Immunopharmacology Oct 2023As a common clinical disease, neuropathic pain is difficult to be cured with drugs. The occurrence and progression of pain is closely related to the response of spinal...
As a common clinical disease, neuropathic pain is difficult to be cured with drugs. The occurrence and progression of pain is closely related to the response of spinal microglia. Aspartof the regulation of microglialactivity,PD-L1 playsacriticalrole. Loss of PD-L1 promoted the polarization of M1-like microglia. Increased expression of PD-L1 promoted M2-like polarization. Electroacupuncture has a significant analgesic effect in clinical practice, but its specific mechanism remains to be further explored. In this study, we verified the role of PD-L1 in EA analgesia and the underlying molecular mechanism through spinal nerve ligation (SNL) in rats and lipopolysaccharide (LPS)-treated BV2 microglial cells. Forbehavioralstudiesofrats,mechanical withdrawal threshold (MWT) and thermal withdrawal latency (TWL) were measured, and spinal cord neuros were examined under transmission electron microscopyto determine changes to their myelin structure. The expression levels of PD-L1 and M1/M2-specific markers in rat spinal cord and BV2 microglial cells were measured by enzyme-linked immunosorbent assay, flow cytometry, immunofluorescence staining and Western blot analysis. Our study showed that EA increased the pain threshold, reduced the destruction of myelin structure, promoted the expression of PD-L1 and PD-1, inhibited the MAPK signaling pathway, and promoted the conversion of microglial polarization from the M1 phenotype to the M2 phenotype in SNL rats. PD-L1 knockdown reversed these effects of EA. In addition, PD-L1 knockdown activated the MAPK signaling pathway, promoted microglial polarization to the M1 phenotype, decreased the expression of anti-inflammatory mediators and increased the expression of proinflammatory factors in LPS-stimulated BV2 microglial cells. Our results showed that EA may regulate the excitability of primary afferent neurons through PD-L1 and then inhibit the MAPK signaling pathway to promote the transformation of activated M1 microglia into M2 microglia, reduce inflammatory reactions, and finally achieve analgesic effects. A therapy targeting PD-L1 may be an effective strategy for treating neuropathic pain.
Topics: Rats; Animals; Microglia; Electroacupuncture; Lipopolysaccharides; B7-H1 Antigen; Spinal Nerves; Neuralgia; Analgesics
PubMed: 37573685
DOI: 10.1016/j.intimp.2023.110764 -
Brazilian Dental Journal 2023In this study, we aimed to evaluate the halitosis and pain threshold of the peri-implant soft tissues in individuals rehabilitated with implant-supported prostheses.... (Observational Study)
Observational Study
In this study, we aimed to evaluate the halitosis and pain threshold of the peri-implant soft tissues in individuals rehabilitated with implant-supported prostheses. Forty-eight subjects were divided into four groups (n = 12) according to their prosthetic rehabilitation: single-tooth fixed prosthesis, multi-tooth fixed prosthesis, overdentures, and the Brånemark protocol. Halitosis was measured using a halimeter, whereas the pain threshold was measured using Von Frey monofilaments. Measurements were taken before (t0) and 30 days after (t1) placement of healing caps, and at the time of (t2) and 30 days after (t3) prosthetic placement. Halitosis data were analyzed using the chi-square test and Bonferroni correction (p < 0.05). Two-way ANOVA and Tukey's test (p < 0.05) were used to analyze pain threshold data. We noted an association between halitosis and time for the Brånemark protocol [X2(6) = 18.471; p = 0.005] and overdenture groups [X2(6) = 17.732; p = 0.007], and between halitosis and type of prosthesis only at t0 [X2(6) = 12.894; p = 0.045]. The interaction between time and the type of prosthesis significantly interfered with the mean pain threshold values (p = 0.001). At most time points, the majority of participants in each group had clinically unacceptable halitosis. After 30 days of using the prostheses, the overdenture group had a lower pain threshold compared to the Brånemark protocol group.
Topics: Humans; Dental Implants; Halitosis; Pain Threshold; Cohort Studies; Tooth; Dental Prosthesis, Implant-Supported
PubMed: 38133082
DOI: 10.1590/0103-6440202305527 -
Neurologia 2023Fibromyalgia syndrome (FM) is a chronic pathology characterised by widespread pain commonly associated with psychological distress affecting quality of life. In recent... (Review)
Review
BACKGROUND
Fibromyalgia syndrome (FM) is a chronic pathology characterised by widespread pain commonly associated with psychological distress affecting quality of life. In recent years, transcranial direct current stimulation (tDCS) and transcranial magnetic stimulation (TMS) have been investigated to treat chronic pain. The aim of the current review is to determine the effects of tDCS and TMS on the main symptoms of patients with FM.
DEVELOPMENT
A systematic review based on PRISMA guidelines was carried out. The search strategy was performed in MEDLINE, SCOPUS, PEDro and Cochrane Library. Randomised controlled trials based on the effects of tDCS and TMS on pain, pressure pain threshold (PPT), fatigue, anxiety and depression, catastrophising and quality of life in patients with FM were analysed. Fourteen studies were included.
CONCLUSIONS
The application of tDCS to the motor cortex is the only intervention shown to decrease pain in the short and medium-term in patients with FM. The application of both interventions showed improvements in PPT, catastrophising and quality of life when applied to the motor cortex, and in fatigue when applied to the dorsolateral prefrontal cortex. The effects of these interventions on anxiety and depression are unclear.
Topics: Humans; Transcranial Direct Current Stimulation; Transcranial Magnetic Stimulation; Fibromyalgia; Quality of Life; Chronic Pain; Fatigue
PubMed: 37031798
DOI: 10.1016/j.nrleng.2020.07.025 -
BMC Medical Education Oct 2023Threshold concepts describe learning experiences that transform our understanding of a concept. Threshold concepts are variously: troublesome, transformative,... (Review)
Review
BACKGROUND
Threshold concepts describe learning experiences that transform our understanding of a concept. Threshold concepts are variously: troublesome, transformative, irreversible, integrative and bounded.
PURPOSE
The aim of this narrative review is to consider the case for characterising pain science and practice as a threshold concept within undergraduate and pre-registration physiotherapy education. This article considers the underlying tenets of threshold concepts as they relate to teaching and learning and the relative merits and limitations of characterising pain science and practice as a threshold concept within undergraduate and pre-registration physiotherapy education from both pedagogical and epidemiological perspectives. By evaluating pain, as it relates to physiotherapy education and practice, according to the five defining characteristics of a threshold concept then presenting data related to the epidemiology and impact of pain, the worthiness of characterising pain science and practice as a threshold concept will be discussed and further debate invited.
Topics: Humans; Learning; Curriculum; Pain; Students; Physical Therapy Modalities
PubMed: 37803373
DOI: 10.1186/s12909-023-04733-z -
The Journal of Pain Jun 2024The evidence that athletes respond to and report indices of experimental pain differently to non-athlete populations was analysed. Databases screened were SPORTDiscus,... (Meta-Analysis)
Meta-Analysis Review
The evidence that athletes respond to and report indices of experimental pain differently to non-athlete populations was analysed. Databases screened were SPORTDiscus, PubMED, PsycArticles, the Cochrane Library (Cochrane Database of Systematic Reviews), Web of Science, Scopus, and CINAHL. Studies that compared experimentally induced pain responses (threshold, tolerance, intensity, unpleasantness, bothersomeness, and effect on performance) in athletes and controls were included. Meta-analyses were performed where appropriate and effects were described as standardised mean differences, pooled using random effects models. Thirty-six studies (2,492 participants) met the inclusion criteria comprising 19 pain tolerance, 17 pain threshold, 21 pain intensity, 5 pain unpleasantness, 2 performance in pain and 1 bothersomeness study. Athletes demonstrated greater pain tolerance (g = .88 [95% confidence interval [CI] .65, .13]) and reported less pain intensity (g = -.80, [95% CI -1.13, -.47]) compared to controls; they also had higher pain threshold but with smaller effects (g = .41, [95% CI .08, .75]). Differences for unpleasantness did not reach statistical significance but the effects were large (g = -1.23 [95% CI -2.29, .18]). Two studies reported that performance in pain was better in contact athletes than non-athletes, and one concluded that athletes find pain less bothersome than controls. There were considerable inconsistencies in the methods employed that were reflected in the meta-analyses' findings. Sub-group analyses of tolerance and intensity were conducted between endurance, contact, and other athlete groups, but were not significant. The data suggest that athletic participation is associated with altered pain responses, but mechanisms remain unclear and more transparent methods are recommended.This study was registered on the PROSPERO site in January 2019 (ref ID: CRD42019119611). PERSPECTIVE: This review examined differences in pain outcomes (threshold, tolerance, intensity, unpleasantness, bothersomeness) and the effect of pain on performance, in athletes versus controls. Meta-analyses revealed athletes had higher threshold and tolerance and found pain less intense than controls; there was some evidence of differences in bothersomeness and performance.
Topics: Humans; Athletes; Pain Threshold; Pain
PubMed: 38154623
DOI: 10.1016/j.jpain.2023.12.007