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Brazilian Journal of Physical Therapy 2023Dry needling is frequently used for the treatment of neck pain but knowledge about its neurophysiological central effects is scarce. (Randomized Controlled Trial)
Randomized Controlled Trial
BACKGROUND
Dry needling is frequently used for the treatment of neck pain but knowledge about its neurophysiological central effects is scarce.
OBJECTIVES
To compare the immediate effects of a single session of dry needling (DN) and sham needling (SN) on local and distant pressure pain thresholds and conditioned pain modulation in patients with chronic idiopathic neck pain.
METHOD
Participants with chronic idiopathic neck pain were randomly allocated to a DN or SN group. The primary outcome measure was the pressure pain threshold (PPT) at one peripheral location: quadriceps muscle (Q). Secondary outcome measures were local PPTs at the treated (most painful) (tUT) and non-treated upper trapezius muscle (ntUT), absolute and relative conditioned pain modulation (CPM) effects and pain during hot water immersion. Patients were assessed at baseline and immediately post intervention. Linear mixed models were used to examine interaction effects as well as between- and within-group differences.
RESULTS
Fifty-four participants were included for statistical analysis. Linear mixed model analyses showed no significant "group X time" interaction effects for any of the outcome measures. The relative CPM effect at the Q was significantly higher post-intervention, compared to baseline within the DN group (mean difference= 13.52%; 95% CI: 0.46, 26.59).
CONCLUSION
The present study shows no superior effect of DN, compared to SN, in the immediate effect on local and distant PPTs and CPM in patients with chronic idiopathic neck pain.
Topics: Humans; Pain Threshold; Neck Pain; Dry Needling; Trigger Points; Chronic Pain
PubMed: 36709694
DOI: 10.1016/j.bjpt.2023.100481 -
European Journal of Pain (London,... Nov 2022Quantitative sensory testing (QST) assesses the functional integrity of small and large nerve fibre afferents and central somatosensory pathways; QST was assumed to...
BACKGROUND
Quantitative sensory testing (QST) assesses the functional integrity of small and large nerve fibre afferents and central somatosensory pathways; QST was assumed to provide insight into the mechanisms of neuropathy. We analysed QST profiles and phenotypes in patients with diabetes mellitus to study whether these could differentiate patients with and without pain and neuropathy.
METHODS
A standardized QST protocol was performed and 'loss and gain of function' abnormalities were analysed in four groups of subjects: diabetic patients with painful (pDSPN; n = 220) and non-painful distal symmetric polyneuropathy (nDSPN; n = 219), diabetic patients without neuropathy (DM; n = 23) and healthy non-diabetic subjects (n = 37). Based on the QST findings, diabetic subjects were further stratified into four predefined prototypic phenotypes: sensory loss (SL), thermal hyperalgesia (TH), mechanical hyperalgesia (MH) and healthy individuals.
RESULTS
Patients in the pDSPN group showed the greatest hyposensitivity ('loss of function'), and DM patients showed the lowest, with statistically significant increases in thermal, thermal pain, mechanical and mechanical pain sensory thresholds. Accordingly, the frequency of the SL phenotype was significantly higher in the pDSPN subgroup (41.8%), than expected (p < 0.0042). The proportion of 'gain of function' abnormalities was low in both pDSPN and nDSPN patients without significant differences.
CONCLUSIONS
There is a continuum in the sensory profiles of diabetic patients, with a more pronounced sensory loss in pDSPN group probably reflecting somatosensory nerve fibre degeneration. An analysis of 'gain of function' abnormalities (allodynia, hyperalgesia) did not offer a key to understanding the pathophysiology of spontaneous diabetic peripheral neuropathic pain.
SIGNIFICANCE
This article, using quantitative sensory testing profiles in large cohorts of diabetic patients with and without polyneuropathy and pain, presents a continuum in the sensory profiles of diabetic patients, with more pronounced 'loss of function' abnormalities in painful polyneuropathy patients. Painful diabetic polyneuropathy probably represents a 'more progressed' type of neuropathy with more pronounced somatosensory nerve fibre degeneration. The proportion of 'gain of function' sensory abnormalities was low, and these offer limited understanding of pathophysiological mechanisms of spontaneous neuropathic pain.
Topics: Diabetes Mellitus; Diabetic Neuropathies; Humans; Hyperalgesia; Neuralgia; Pain Measurement; Pain Threshold; Polyneuropathies
PubMed: 36069121
DOI: 10.1002/ejp.2034 -
Sleep Medicine May 2018Although night-shift work (NSW) is associated with a higher risk for several physical and mental disorders, the impact of NSW on pain perception is still unclear. This...
BACKGROUND
Although night-shift work (NSW) is associated with a higher risk for several physical and mental disorders, the impact of NSW on pain perception is still unclear. This study investigates the impact of NSW on cold pain perception considering the impact of mood and sleepiness.
METHOD
Quantitative sensory testing (QST) was performed in healthy night-shift workers. Cold pain threshold as well as tonic cold pain was assessed after one habitual night (T1), after a 12-hour NSW (T2) and after one recovery night (T3). Sleep quality was measured with the Pittsburgh Sleep Quality Index (PSQI) before T1, sleepiness with the Stanford Sleepiness Scale (SSS) and mood with a German short-version of the Profile of Mood States (ASTS) at T1, T2 and T3. Depending on the distribution of the data, ANOVAs or Friedman tests as well as t- or Wilcoxon tests were performed.
RESULTS
Nineteen healthy shift-workers (13 females; 29.7 ± 7.5 years old; 8.1 ± 6.6 years in shift work, PSQI: 4.7 ± 2.2) were included. Tonic cold pain showed a significant difference between T1 (48.2 ± 27.5 mm), T2 (61.7 ± 26.6 mm; effect size: Cohen's d=.49; percent change 28%), and T3 (52.1 ± 28.7 mm) on a 0-100 mm Visual Analog Scale (p = 0.007). Cold pain threshold changed from 11.0 ± 7.9 °C (T1) to 14.5 ± 8.8 °C (T2) (p = 0.04), however, an ANOVA comparing T1, T2, and T3 was not significant (p = 0.095). Sleepiness (SSS) and mood (ASTS) changed significantly between T1, T2 and T3 (p-values < 0.01). The change of mood but not of sleepiness correlated with the difference in tonic cold pain from T1 to T2 (R: 0.53; R: 0.29; p = 0.022).
DISCUSSION
NSW increases cold pain perception. The same tonic cold pain stimulus is rated 28% more painful after NSW and normalizes after a recovery night. Increases in cold pain perception due to NSW appear to be more strongly related to changes in mood as compared to changes in sleepiness.
Topics: Adult; Affect; Cold Temperature; Female; Humans; Male; Pain Perception; Pain Threshold; Shift Work Schedule; Sleepiness
PubMed: 29680433
DOI: 10.1016/j.sleep.2017.12.014 -
Journal of Medical Internet Research Jul 2022Virtual reality hypnosis (VRH) is a promising tool to reduce pain. However, the benefits of VRH on pain perception and on the physiological expression of pain require... (Randomized Controlled Trial)
Randomized Controlled Trial
BACKGROUND
Virtual reality hypnosis (VRH) is a promising tool to reduce pain. However, the benefits of VRH on pain perception and on the physiological expression of pain require further investigation.
OBJECTIVE
In this study, we characterized the effects of VRH on the heat pain threshold among adult healthy volunteers while monitoring several physiological and autonomic functions.
METHODS
Sixty healthy volunteers were prospectively included to receive nociceptive stimulations. The first set of thermal stimuli consisted of 20 stimulations at 60°C (duration 500 milliseconds) to trigger contact heat evoked potentials (CHEPs). The second set of thermal stimuli consisted of ramps (1°C/second) to determine the heat pain threshold of the participants. Electrocardiogram, skin conductance responses, respiration rate, as well as the analgesia nociception index were also recorded throughout the experiment.
RESULTS
Data from 58 participants were analyzed. There was a small but significant increase in pain threshold in VRH (50.19°C, SD 1.98°C) compared to that in the control condition (mean 49.45°C, SD 1.87; P<.001, Wilcoxon matched-pairs signed-rank test; Cohen d=0.38). No significant effect of VRH on CHEPs and heart rate variability parameters was observed (all P>0.5; n=22 and n=52, respectively). During VRH, participants exhibited a clear reduction in their autonomic sympathetic tone, as shown by the lower number of nonspecific skin conductance peak responses (P<.001, two-way analysis of variance; n=39) and by an increase in the analgesia nociception index (P<.001, paired t-test; n=40).
CONCLUSIONS
The results obtained in this study support the idea that VRH administration is effective at increasing heat pain thresholds and impacts autonomic functions among healthy volunteers. As a nonpharmacological intervention, VRH has beneficial action on acute experimental heat pain. This beneficial action will need to be evaluated for the treatment of other types of pain, including chronic pain.
Topics: Adult; Biomarkers; Cross-Over Studies; Humans; Hypnosis; Pain; Pain Threshold; Prospective Studies; Virtual Reality
PubMed: 35904872
DOI: 10.2196/33255 -
Pain Mar 2023Persistent pain despite satisfactory disease treatment is frequent in rheumatoid arthritis (RA) and spondyloarthritis (Spa) and may result from specific changes in...
Persistent pain despite satisfactory disease treatment is frequent in rheumatoid arthritis (RA) and spondyloarthritis (Spa) and may result from specific changes in central pain processing. We assessed these mechanisms further by systematically comparing thermal pain thresholds and conditioned pain modulation (CPM) between patients with active RA or Spa and healthy controls. We included 50 patients with RA and 50 patients with Spa and 100 age-matched and sex-matched controls. Heat and cold pain thresholds (HPT-CPT) were measured on the dominant forearm, and CPM was assessed by applying conditioning stimuli (immersion in a cold-water bath) to one foot and the nondominant hand in 2 successive randomized sequences. Descending pain modulation was assessed as the difference in HPTs (in °C) before and after conditioning. Larger HPT differences (ie, a larger CPM effect) reflected more efficient descending inhibition. Potential associations between changes in CPM and clinical data, including disease activity, pain intensity, and psychological and functional variables, were systematically assessed. Heat pain threshold and cold pain threshold were similar in patients and controls. The mean CPM effect was significantly weaker in patients than that in controls for conditioning applied to either the foot (0.25°C ±2.57 vs 2.79°C ±2.31; P < 0.001) or the nondominant hand (0.57°C ±2.74 vs 2.68°C ±2.12; P < 0.001). The smaller CPM effect in patients was correlated with average pain intensity, but not with disease activity or other clinical characteristics, suggesting a significant pathophysiological role for changes in endogenous pain modulation in the mechanisms of chronic pain associated with inflammatory rheumatism.
Topics: Humans; Chronic Pain; Rheumatic Fever; Conditioning, Psychological; Pain Threshold; Pain Measurement; Arthritis, Rheumatoid
PubMed: 35984362
DOI: 10.1097/j.pain.0000000000002745 -
Early Human Development Jul 2017Data on long-term consequences of neonatal pain is limited. (Observational Study)
Observational Study
BACKGROUND
Data on long-term consequences of neonatal pain is limited.
AIM
To assess whether perinatal factors, later pain experience and pain coping strategies are associated with altered pain threshold, pain tolerance and pain intensity in adolescents born preterm.
STUDY DESIGN
Observational, longitudinal study (Project on Preterm and SGA-infants, POPS-19).
SUBJECTS
We analyzed data of 412 adolescents at the age of 19years, who were born at a gestational age<32weeks or with a birth weight<1500g.
OUTCOME MEASURES
Participants performed a standardized cold pressor test to assess pain threshold, tolerance and intensity. Furthermore, they completed a pain coping questionnaire (PCQ).
RESULTS
In univariate analysis, female gender and necrotizing enterocolitis (NEC) were associated with lower pain tolerance, indicated by reaching the ceiling time of 180s in ice water (females 19% vs males 29%, NEC 7% vs no NEC 25%). Female gender was associated with higher pain intensity (mean difference 0.58; 95%CI 0.21; 0.95) and lower pain threshold (log rank test p 0.007). In a multivariate Cox regression analyses, emotion focused avoidance pain coping style was significantly associated with lower pain threshold (hazard ratio HR 1.38; 95%CI 1.02; 1.87) and pain tolerance (HR 1.72; 95%CI 1.21; 2.42). NEC was significantly associated with lower pain threshold (HR 1.47; 95%CI 1.01; 2.14) and pain tolerance (HR 1.63; 95%CI 1.09; 2.41).
CONCLUSION
In adolescence, maladaptive pain coping strategy was associated with lower pain threshold, pain tolerance and higher pain intensity. NEC was associated with altered pain response in adolescents born preterm.
Topics: Enterocolitis, Necrotizing; Female; Humans; Infant, Extremely Premature; Infant, Low Birth Weight; Infant, Newborn; Longitudinal Studies; Male; Pain Threshold; Young Adult
PubMed: 28499135
DOI: 10.1016/j.earlhumdev.2017.05.001 -
Current Pharmaceutical Design 2017Background Experimental studies have shown that neonatal exposure to stress, pain, opioids and anaesthetics may cause histologic and morphologic changes in the central... (Review)
Review
Background Experimental studies have shown that neonatal exposure to stress, pain, opioids and anaesthetics may cause histologic and morphologic changes in the central nervous system with associated functional and behavioural changes in the long term. An important question is whether this holds true for humans also - and in particular for sick neonates who often are exposed to pain and receive anaesthetics and sedatives. Methods In this narrative review, we evaluate the effects of neonatal exposure to stress, pain, opioids and anaesthetics in infancy and childhood in animals and in preterm born and term born humans on pain sensitivity, brain morphology, cognition and behaviour later in life. Results In animals, neonatal exposure to stress, pain, opioids and early exposure to anaesthetics are associated with neurodegeneration and cognitive problems later in life. Human studies mainly focus on pain sensitivity, cognition and behaviour and find contradictory outcomes. Dramatic long-term effects found in animal studies could not be confirmed in human. Conclusion While studies in animals suggest neurotoxic effects of early exposure to stress, pain, opioids and anaesthetics, these effects seem clinically less relevant in humans. A possible reason is that the latter often receive opioids in the presence of pain and opioids and anaesthetics in balanced therapeutic dosages and with adequate monitoring of physiological parameters, in contrast to animal studies.
Topics: Analgesics, Opioid; Anesthetics; Animals; Brain; Cognition; Humans; Infant, Newborn; Mental Status and Dementia Tests; Pain; Pain Threshold; Stress, Psychological; Time Factors; Treatment Outcome
PubMed: 28950826
DOI: 10.2174/1381612823666170926150259 -
European Journal of Pain (London,... Jul 2017Literature suggests that pain perception diminishes in old age. The most recent review used search strategies conducted over a decade ago and concluded that study... (Meta-Analysis)
Meta-Analysis Review
UNLABELLED
Literature suggests that pain perception diminishes in old age. The most recent review used search strategies conducted over a decade ago and concluded that study findings were equivocal. The aim of this systematic review, with meta-analysis, was to determine age-related changes in pain sensitivity in healthy pain-free adults, children and adolescents. A search of PubMed, Science Direct, and PsycINFO identified studies that compared pain sensitivity response to noxious stimuli at different time points in the lifespan of healthy individuals. Selected studies were assessed for methodological quality and data pooled and meta-analysed. Publication bias was tested using Funnel plots. Twelve studies were included in the review (study sample sizes 30-244 participants). Seven of nine studies found statistically significant differences in pain sensitivity response between old (mean ± SD 62.2 ± 3.4 to 79 ± 4 years) and younger adults (22 ± 1.5 to 39.1 ± 8.8 years), but the direction of change was inconsistent. Meta-analysis found that pressure pain threshold was lower in old adults compared with younger adults (p = 0.018, I = 60.970%). There were no differences in contact heat pain thresholds between old and younger adults (p = 0.0001, I = 90.23%). Three studies found that younger children (6-8.12 years) were more sensitive to noxious stimuli than older children (9-14 years). Methodological quality of studies was high, with a low risk of publication bias. There was substantial statistical and methodological heterogeneity. There is tentative evidence that pressure pain threshold was lower in old adults compared with younger adults, with no differences in heat pain thresholds. Further studies are needed.
SIGNIFICANCE
There is tentative evidence that old adults may be more sensitive to mechanically-evoked pain but not heat-evoked pain than young adults. There is a need for further studies on age-related changes in pain perception.
Topics: Adolescent; Adult; Age Factors; Aged; Aged, 80 and over; Aging; Child; Humans; Middle Aged; Pain; Pain Perception; Pain Threshold; Young Adult
PubMed: 28230292
DOI: 10.1002/ejp.1011 -
Journal of Occupational Health 2023This study aimed to quantitatively confirm the effects of dental specialists' work and stretching on musculoskeletal pain.
OBJECTIVE
This study aimed to quantitatively confirm the effects of dental specialists' work and stretching on musculoskeletal pain.
METHODS
The pain pressure threshold was divided into five parts (neck, shoulder, trunk, lower back, and hand/arm) of the upper body and measured at 15 muscle trigger points. The pain pressure threshold before and after work was measured, and 30 min of stretching and rest were stipulated as an intervention.
RESULTS
The pain pressure thresholds reduced significantly in all muscles after work (P < .05). In the stretching group, the pain pressure thresholds increased significantly in all muscles (P < .05). In particular, the iliocostalis lumborum (lower back), rhomboid (trunk), transverse carpal ligament (hand/arm), levator scapulae-superior angle (neck), and upper trapezius (shoulder) muscles showed the greatest decrease in pain pressure threshold after work and the greatest increase after stretching.
CONCLUSIONS
Stretching helps immediately relieve musculoskeletal pain in dental professionals and can prevent and manage work-related musculoskeletal disorders.
Topics: Humans; Musculoskeletal Pain; Muscle, Skeletal; Pain Threshold; Neck Pain; Dentists
PubMed: 37347801
DOI: 10.1002/1348-9585.12413 -
Pain Sep 2019Hypersensitivity due to central pain mechanisms can influence recovery and lead to worse clinical outcomes, but the ability of quantitative sensory testing (QST), an... (Meta-Analysis)
Meta-Analysis Review
Hypersensitivity due to central pain mechanisms can influence recovery and lead to worse clinical outcomes, but the ability of quantitative sensory testing (QST), an index of sensitisation, to predict outcomes in chronic musculoskeletal disorders remains unclear. We systematically reviewed the evidence for ability of QST to predict pain, disability, and negative affect using searches of CENTRAL, MEDLINE, EMBASE, AMED, CINAHL, and PubMed databases up to April 2018. Title screening, data extraction, and methodological quality assessments were performed independently by 2 reviewers. Associations were reported between baseline QST and outcomes using adjusted (β) and unadjusted (r) correlations. Of the 37 eligible studies (n = 3860 participants), 32 were prospective cohort studies and 5 randomised controlled trials. Pain was an outcome in 30 studies, disability in 11, and negative affect in 3. Meta-analysis revealed that baseline QST predicted musculoskeletal pain (mean r = 0.31, 95% confidence interval [CI]: 0.23-0.38, n = 1057 participants) and disability (mean r = 0.30, 95% CI: 0.19-0.40, n = 290 participants). Baseline modalities quantifying central mechanisms such as temporal summation and conditioned pain modulation were associated with follow-up pain (temporal summation: mean r = 0.37, 95% CI: 0.17-0.54; conditioned pain modulation: mean r = 0.36, 95% CI: 0.20-0.50), whereas baseline mechanical threshold modalities were predictive of follow-up disability (mean r = 0.25, 95% CI: 0.03-0.45). Quantitative sensory testing indices of pain hypersensitivity might help develop targeted interventions aiming to improve outcomes across a range of musculoskeletal conditions.
Topics: Affect; Disabled Persons; Humans; Musculoskeletal Pain; Pain Measurement; Pain Threshold; Prognosis; Prospective Studies; Randomized Controlled Trials as Topic
PubMed: 31045746
DOI: 10.1097/j.pain.0000000000001590