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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 -
Chiropractic & Manual Therapies Feb 2021Pain hypersensitivity can be assessed using Quantitative Sensory Testing (QST) and is associated with persistent low back pain. Spinal manipulation appears to modify... (Randomized Controlled Trial)
Randomized Controlled Trial
BACKGROUND
Pain hypersensitivity can be assessed using Quantitative Sensory Testing (QST) and is associated with persistent low back pain. Spinal manipulation appears to modify pain hypersensitivity, and this could function as one mechanism leading to clinical improvements. In the current study, we applied a comprehensive QST battery to assess pain sensitivity in a cohort of low back pain patients before and after spinal manipulation to improve our understanding of the association between QST and clinical improvements. This study addresses two questions: Are clinical improvements following spinal manipulation in low back pain patients contingent on pain hypersensitivity, and does pain sensitivity change following spinal manipulation?
METHODS
We performed a secondary analysis of data from a randomized clinical trial. One hundred and thirty-two participants with persistent LBP were treated with spinal manipulation four times over two weeks. Patient-reported outcomes and QST were assessed at baseline, after the fourth spinal manipulation session, and 14-days later. The clinical outcomes were changes in low back pain intensity and disability. Using latent profile analysis, we categorized the participants into clusters depending on their baseline QST scores. We used linear mixed models to examine the association between clusters and changes in patient-reported outcomes and QST.
RESULTS
Two clusters emerged: a Sensitized and a Not sensitized. The former had significantly lower regional pressure and thermal pain thresholds, remote pressure pain tolerance, and lower inhibitory conditioned pain modulation than the Not sensitized group. However, we only found between-cluster differences for regional pressure pain threshold following spinal manipulation. Thus, the clusters were not associated with patient-reported pain and disability changes or the remaining QST outcomes.
CONCLUSIONS
We report that the baseline QST profile was not associated with clinical improvements following spinal manipulation. We did observe a substantial change for regional pressure pain threshold, which suggests that any effect of spinal manipulation on pain sensitivity is most likely to be observed as changes in regional, mechanical pain threshold. However, the mechanism that invokes clinical improvement and pain sensitivity changes appear distinct. Due to methodological caveats, we advise caution when interpreting the results.
TRIAL REGISTRATION
Clinical.Trial.gov identifier: NCT04086667 , registered 11 September 2019 - Retrospectively registered, https://clinicaltrials.gov/ct2/show/NCT04086667.
Topics: Adult; Cluster Analysis; Disability Evaluation; Female; Humans; Low Back Pain; Male; Manipulation, Spinal; Middle Aged; Pain Measurement; Pain Threshold; Patient Reported Outcome Measures
PubMed: 33627163
DOI: 10.1186/s12998-021-00367-4 -
Pain Apr 2015
Topics: Back Pain; Chronic Pain; Female; Humans; Male; Pain Threshold; Psychological Trauma
PubMed: 25790449
DOI: 10.1097/j.pain.0000000000000098 -
Scandinavian Journal of Pain Jan 2023Paradoxical sensations, known as thermal pain illusions, can be evoked by painful cold-heat pulse stimulation. They may provide diagnostic value; however, the possible...
OBJECTIVES
Paradoxical sensations, known as thermal pain illusions, can be evoked by painful cold-heat pulse stimulation. They may provide diagnostic value; however, the possible interaction between conditioned pain modulation and thermal pain illusions has not been explored. The present study examined: (1) whether conditioned pain modulation could be induced by alternating tonic painful cold-heat pulse stimulation; and (2) whether the presence of thermal pain illusions during the conditioning stimulus influences the degree of conditioned pain modulation.
METHODS
This study was approved by the Ethics Committee of Meikai University (A1507). Conditioned pain modulation was provoked using alternating painful cold-heat pulses delivered at 20-s intervals applied to the forearm. Thermal pain illusions were qualitatively evaluated, and conditioned pain modulation was assessed quantitatively using the pressure pain threshold as a test stimulus. Differences in the conditioned pain modulation effect between the participants who experienced thermal pain illusions and those who did not were analysed using Student's -test.
RESULTS
A significant positive conditioned pain modulation effect (51.0 ± 4.7%, overall effect) was detected. There was no significant difference in conditioned pain modulation between the participants who experienced thermal pain illusions and those who did not (44.3 ± 6.0% and 55.5 ± 6.8%, respectively; p = 0.255).
CONCLUSIONS
Conditioned pain modulation induced by alternating painful conditioning cold-heat pulse stimulation was identical during the conditioning stimulation in volunteers with and without thermal pain illusions. Conditioning cold-heat pulse stimulation is useful to evaluate conditioned pain modulation. Moreover, conditioned pain modulation is not influenced by the presence of thermal pain illusions, indicating partially different underlying supraspinal, neuronal networks.
Topics: Humans; Illusions; Pain Measurement; Pain; Pain Threshold; Hot Temperature
PubMed: 35607757
DOI: 10.1515/sjpain-2022-0037 -
The Clinical Journal of Pain Jul 2022The aim of this study was to investigate if somatosensory profiles can differentiate pain and psychophysiological symptoms among young adults with irritable bowel... (Randomized Controlled Trial)
Randomized Controlled Trial
OBJECTIVE
The aim of this study was to investigate if somatosensory profiles can differentiate pain and psychophysiological symptoms among young adults with irritable bowel syndrome (IBS).
METHODS
We performed a cluster analysis of data collected from a randomized clinical trial of 80 IBS patients and 21 age-matched healthy controls (HCs) to stratify pain and symptoms among young adults with IBS by their peripheral sensory profiles. Data of quantitative sensory testing and IBS-related pain and symptoms were collected at baseline and 6-week and 12-week follow-ups.
RESULTS
Using the K-means method, IBS patients were classified into 2 clusters, the "IBS normal threshold" (IBS-NT) and the "IBS increased threshold" (IBS-IT). The IBS-NT cluster had a similar pain threshold as the HCs, and the IBS-IT cluster had an increased threshold of somatic pain perception (lower cold pain threshold, higher heat pain threshold, and higher pressure pain threshold, all P<0.001) than HCs. Compared with the IBS-NT cluster, the IBS-IT cluster reported higher levels of IBS-related pain intensity, anxiety, fatigue, and sleep disturbance over the 3 visits (all P<0.05).
DISCUSSION
Young adults with IBS fell into 2 clusters, one with a similar sensory threshold as the HCs and another with an increased pain threshold, who reported higher pain intensity and more severe symptoms. Somatic sensory profiles should be integrated into further personalized self-management intervention among patients with IBS.
Topics: Cluster Analysis; Humans; Irritable Bowel Syndrome; Nociceptive Pain; Pain Measurement; Pain Threshold; Young Adult
PubMed: 35686579
DOI: 10.1097/AJP.0000000000001046 -
Clinical Oral Investigations Mar 2022Pain on palpation of jaw muscles is a commonly used diagnostic criterion when examining patients with orofacial pain. It is not known, however, if pain reports are...
OBJECTIVES
Pain on palpation of jaw muscles is a commonly used diagnostic criterion when examining patients with orofacial pain. It is not known, however, if pain reports are affected by the gender of the examiner. Our aim was to investigate if pressure pain threshold (PPT), pressure pain tolerance (PTol), and pain intensity assessed over the masseter muscles in healthy individuals are affected by the gender of the examiner.
MATERIALS AND METHODS
Healthy, pain-free individuals were recruited on a voluntary basis. PPT and PTol were assessed using pressure algometry. At the PTol level, participants also rated pain intensity on a 0-10 numeric rating scale. Assessments of PPT and PTol were conducted with six repeated measurements performed twice, separately by one female and one male examiner, on each participant.
RESULTS
In total, 84 participants (43 women; median age 24, IQR 6) were included. With a female examiner, women reported higher pain intensity than men (Mann Whitney U, p = 0.005). In the multivariable analysis, significantly higher PTol was predicted by male examiner. Also, a higher ratio between PTol and reported pain intensity was predicted by male examiner.
CONCLUSIONS
The gender of the examiner influences pain reporting and perception in an experimental setting. This effect on pain perception related to gender of the examiner is probably related to normative gender behaviors rather than to biological alterations within the examined individual.
CLINICAL RELEVANCE
In clinical and experimental settings, gender of the examiner may affect not only pain perception but also pain reporting, with potential implications for diagnostics in patients with pain.
Topics: Adult; Facial Pain; Female; Healthy Volunteers; Humans; Male; Pain Measurement; Pain Perception; Pain Threshold; Young Adult
PubMed: 34902057
DOI: 10.1007/s00784-021-04286-9 -
Scandinavian Journal of Pain Jul 2017
Topics: Humans; Low Back Pain; Movement; Pain Threshold
PubMed: 28850399
DOI: 10.1016/j.sjpain.2017.03.008 -
Conditioned Pain Modulation in Children: The Effects of Painful and Nonpainful Conditioning Stimuli.The Journal of Pain Jul 2022Conditioned pain modulation (CPM), a psychophysical measure in which 1 pain stimulus (conditioning stimulus) is used to inhibit another pain stimulus (test stimulus), is...
Conditioned pain modulation (CPM), a psychophysical measure in which 1 pain stimulus (conditioning stimulus) is used to inhibit another pain stimulus (test stimulus), is an important indicator of endogenous pain inhibition in adults, but is understudied in children. Preliminary evidence suggests that CPM effects are present in healthy children and are more robust in adolescents. However, developmental differences in younger children are not well documented and few studies control for potential distraction effects of the conditioning stimulus (CS). Participants were 54 healthy children aged 6 to 12 years. After a baseline pressure pain threshold (PPT) test, participants underwent 2 conditioning trials in which PPT was assessed while they placed their left hand in a water bath maintained at either 12 °C (painful CS) or 22 °C (nonpainful sham CS) in counterbalanced order. Results revealed a significant CPM effect. PPT values were significantly higher relative to baseline during the painful CS trial; PPT during the nonpainful CS trial did not differ from baseline. There were no significant age differences in magnitude of CPM effect. The results indicate that children as young as 6 years of age demonstrate CPM, suggesting that descending inhibitory pathways may be better developed in young children than previously thought. PERSPECTIVE: This study was successful in producing inhibitory CPM effects in physically healthy children while controlling for sensory distraction. The findings provide strong evidence that the obtained CPM responses cannot be attributed to sensory distraction or other nonspecific effects. Future studies could utilize CPM paradigms to study various aspects of pediatric endogenous pain inhibition, in order to better predict pain responses and improve interventions.
Topics: Adolescent; Adult; Child; Child, Preschool; Conditioning, Classical; Conditioning, Psychological; Humans; Pain; Pain Measurement; Pain Threshold
PubMed: 35189351
DOI: 10.1016/j.jpain.2022.02.004 -
Journal of Anatomy Jul 2005Functional imaging techniques have allowed researchers to look within the brain, and revealed the cortical representation of pain. Initial experiments, performed in the... (Review)
Review
Functional imaging techniques have allowed researchers to look within the brain, and revealed the cortical representation of pain. Initial experiments, performed in the early 1990s, revolutionized pain research, as they demonstrated that pain was not processed in a single cortical area, but in several distributed brain regions. Over the last decade, the roles of these pain centres have been investigated and a clearer picture has emerged of the medial and lateral pain system. In this brief article, we review the imaging literature to date that has allowed these advances to be made, and examine the new frontiers for pain imaging research: imaging the brainstem and other structures involved in the descending control of pain; functional and anatomical connectivity studies of pain processing brain regions; imaging models of neuropathic pain-like states; and going beyond the brain to image spinal function. The ultimate goal of such research is to take these new techniques into the clinic, to investigate and provide new remedies for chronic pain sufferers.
Topics: Brain; Humans; Magnetic Resonance Imaging; Neural Pathways; Nociceptors; Pain; Pain Threshold; Perception; Positron-Emission Tomography; Spine
PubMed: 16011543
DOI: 10.1111/j.1469-7580.2005.00428.x -
Rheumatic Diseases Clinics of North... May 2009Many chronic pain syndromes are associated with hypersensitivity to painful stimuli and with reduced endogenous pain inhibition. These findings suggest that modulation... (Review)
Review
Many chronic pain syndromes are associated with hypersensitivity to painful stimuli and with reduced endogenous pain inhibition. These findings suggest that modulation of pain-related information may be linked to the onset or maintenance of chronic pain. The combination of heightened pain sensitivity and reduced pain inhibition seems to predispose individuals to greater risk for increased acute clinical pain. It is unknown whether such pain processing abnormalities may also place individuals at increased risk for chronic pain. Psychophysical methods can be used for the evaluation of pain sensitivity and pain inhibition. Long-term prospective studies that could yield insight into the role of heightened pain sensitivity and pain disinhibition for the development of chronic pain disorders like fibromyalgia in the general population are lacking, however.
Topics: Animals; Chronic Disease; Fibromyalgia; Humans; Pain; Pain Threshold
PubMed: 19647141
DOI: 10.1016/j.rdc.2009.05.006