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Roger B Fillingim - One of the best experts on this subject based on the ideXlab platform.

  • bayesian analysis of the effect of transcranial direct current stimulation on experimental Pain sensitivity in older adults with knee osteoarthritis randomized sham controlled pilot Clinical study
    Journal of Pain Research, 2018
    Co-Authors: Hyochol Ahn, Adam J Woods, Eunyoung Choi, Robert Suchting, Hongyu Miao, Charles E Green, Raymond Y Cho, Roger B Fillingim
    Abstract:

    Purpose Previous studies have indicated that transcranial direct current stimulation (tDCS) with the anode over the motor cortex and the cathode over the contralateral supraorbital region is effective in reducing Clinical Pain in patients with chronic Pain, but these studies have not focused on experimental Pain sensitivity. Therefore, the aim of this study was to examine the effect of tDCS on experimental Pain sensitivity in older adults with knee osteoarthritis (OA). Patients and methods Forty community-dwelling participants aged 50-70 years with knee OA Pain were randomly assigned to receive five daily sessions of 2 mA tDCS for 20 minutes (n = 20) or sham tDCS (n = 20) using a parallel group design. A multimodal quantitative sensory testing battery was completed, including heat Pain, pressure Pain threshold (PPT), punctate mechanical Pain, and conditioned Pain modulation (CPM). Results The active tDCS group showed greater increases in heat Pain thresholds and tolerances, PPTs, and CPM, and reductions in punctate Pain. In addition, beneficial changes in experimental Pain measures were associated with reductions in Clinical Pain. Future studies are needed to extend these findings to better understand the underlying mechanisms of tDCS as well as to optimize treatment parameters including number and duration of stimulation sessions. Conclusion Our findings demonstrate that tDCS reduces experimental Pain sensitivity, and these beneficial changes in experimental Pain measures were associated with reductions in Clinical Pain.

  • efficacy of transcranial direct current stimulation over primary motor cortex anode and contralateral supraorbital area cathode on Clinical Pain severity and mobility performance in persons with knee osteoarthritis an experimenter and participant bli
    Brain Stimulation, 2017
    Co-Authors: Adam J Woods, Mark E Kunik, Abhishek Bhattacharjee, Zhiguo Chen, Eunyoung Choi, Roger B Fillingim
    Abstract:

    Abstract Background Previous studies indicate that transcranial direct current stimulation (tDCS) with anode over motor cortex (M1) and cathode over contralateral supraorbital region (SO) may be effective in reducing Pain, but these studies are limited in number and have not focused on older adults with osteoarthritis (OA). Objective To evaluate the preliminary efficacy and safety of M1-SO applied tDCS on Clinical Pain severity and mobility performance in adults with knee OA Pain. Methods Forty 50- to 70-year-old community-dwelling participants with knee OA were randomly assigned to receive five daily sessions of 2 mA tDCS for 20 min (n = 20) or sham tDCS (n = 20). We measured Clinical Pain severity via Numeric Rating Scale, Western Ontario and McMaster Universities Osteoarthritis Index, and Short-Form McGill Pain Questionnaire. In addition, we measured mobility performance using the 6-Minute Walk Test and the Short Physical Performance Battery. Moreover, we obtained a sensation/safety questionnaire and measured cognition changes using the PROMIS-Applied Cognition-Abilities-Short Form 8a. Results Active tDCS over M1-SO significantly reduced Numeric Rating Scale of Pain compared to sham tDCS after completion of the five daily sessions, and remained up to three weeks. No other measures were significantly different from sham. Participants tolerated tDCS over M1-SO well without serious adverse effects or cognition changes. Conclusion Although not consistent in all Pain measurements, our findings demonstrate promising Clinical efficacy for reduction in Pain perception for older adults with knee OA. Trial registration ClinicalTrials.gov Identifier NCT02512393 .

  • testing assumptions in human Pain models psychophysical differences between first and second Pain
    The Journal of Pain, 2017
    Co-Authors: Nathanial R Eckert, Roger B Fillingim, Yenisel Cruzalmeida, Charles J Vierck, Corey B Simon, Joseph L Riley
    Abstract:

    Abstract Acute Pain arises from activation of myelinated (A delta) and unmyelinated (C) nociceptive afferents, leading to first (A-fiber) or second (C-fiber) Pain sensations. The current study sought to investigate first and second Pain within glabrous and hairy skin sites in human upper limbs. Fifty healthy adults (25 male/25 female, 18–30 years old, mean = 20.5 ± 1.4 years) participated in a psychophysical study investigating electronically rated, thermal first and second Pain sensations within the glabrous skin at the palm and hairy skin of the forearm. Repeated measures analysis of variance indicated that the threshold for first Pain was lower (more sensitive) than for second Pain ( P  = .004), for glabrous as well as hairy skin, and thresholds at glabrous skin were higher than for hairy skin ( P  = .001). Hairy skin presented a steeper slope for testing, whereas there were no differences in slope between first and second Pain. The study findings support assumptions associated with mechanistic differences between first and second Pain sensations, while offering a novel method for producing first and second Pain with the same thermal stimulus. Efforts to understand abnormalities among people with Clinical Pain and development of new therapeutic agents will benefit from specific psychophysical methods. Perspective This article presents a novel method for directly comparing first and second Pain within the same thermal stimulus. The ability to directly compare first and second Pain sensations can aid in understanding Pain abnormalities in Clinical Pain and development of therapeutic aids.

  • slow temporal summation of Pain for assessment of central Pain sensitivity and Clinical Pain of fibromyalgia patients
    PLOS ONE, 2014
    Co-Authors: Roland Staud, Elizabeth E Weyl, Joseph L Riley, Roger B Fillingim
    Abstract:

    Background In healthy individuals slow temporal summation of Pain or wind-up (WU) can be evoked by repetitive heat-pulses at frequencies of ≥.33 Hz. Previous WU studies have used various stimulus frequencies and intensities to characterize central sensitization of human subjects including fibromyalgia (FM) patients. However, many trials demonstrated considerable WU-variability including zero WU or even wind-down (WD) at stimulus intensities sufficient for activating C-nociceptors. Additionally, few WU-protocols have controlled for contributions of individual Pain sensitivity to WU-magnitude, which is critical for WU-comparisons. We hypothesized that integration of 3 different WU-trains into a single WU-response function (WU-RF) would not only control for individuals’ Pain sensitivity but also better characterize their central Pain responding including WU and WD. Methods 33 normal controls (NC) and 38 FM patients participated in a study of heat-WU. We systematically varied stimulus intensities of.4 Hz heat-pulse trains applied to the hands. Pain summation was calculated as difference scores of 1st and 5th heat-pulse ratings. WU-difference (WU-Δ) scores related to 3 heat-pulse trains (44°C, 46°C, 48°C) were integrated into WU-response functions whose slopes were used to assess group differences in central Pain sensitivity. WU-aftersensations (WU-AS) at 15 s and 30 s were used to predict Clinical FM Pain intensity. Results WU-Δ scores linearly accelerated with increasing stimulus intensity (p NC) from WD to WU. Slope of WU-RF, which is representative of central Pain sensitivity, was significantly steeper in FM patients than NC (p<.003). WU-AS predicted Clinical FM Pain intensity (Pearson’s r = .4; p<.04). Conclusions Compared to single WU series, WU-RFs integrate individuals’ Pain sensitivity as well as WU and WD. Slope of WU-RFs was significantly different between FM patients and NC. Therefore WU-RF may be useful for assessing central sensitization of chronic Pain patients in research and Clinical practice.

  • BDI � Beck Depression Inventory; IPTO � ischemic
    2013
    Co-Authors: Robert R Edwards, Roger B Fillingim, Daniel M. Doleys, Daniel Lowery
    Abstract:

    Objective: Although numerous studies have independently examined ethnic differences in Clinical and experimental Pain, few have investigated differences in both sensitivity to controlled noxious stimuli and Clinical Pain reports in the same sample. The present experiment examined the effects of ethnicity (African American vs. white) on experimental Pain tolerance and adjustment to chronic Pain. Methods: Three hundred thirty-seven (68 African American and 269 white) patients with chronic Pain referred to a multidisciplinary treatment center participated in the study. In addition to completing a number of standardized questionnaires assessing adjustment to chronic Pain, participants underwent a submaximal effort tourniquet procedure. This experimental Pain procedure yields a measure of tolerance for a controlled noxious stimulus (ie, arm ischemia). Results: African American subjects reported higher levels of Clinical Pain as well as greater Pain-related disability than white participants. In addition, substantial group differences were observed for ischemic Pain tolerance, with African Americans demonstrating less tolerance than whites. Correlational analyses revealed a small but significant inverse relationship between ischemic Pain tolerance and the reported severity of chronic Pain. Conclusions: Collectively these findings support previous research revealing ethnic differences in responses to both Clinical and experimental Pain. Moreover, the present results suggest that enhanced sensitivity to noxious stimuli on the part of African Americans may be associated with ethnic differences in reported Clinical Pain, although the magnitude of ethnic differences was muc

Steven Z George - One of the best experts on this subject based on the ideXlab platform.

  • suprathreshold heat Pain response is associated with Clinical Pain intensity for patients with shoulder Pain
    The Journal of Pain, 2011
    Co-Authors: Carolina Valencia, Roger B Fillingim, Steven Z George
    Abstract:

    Abstract Quantitative sensory testing (QST) has become commonly used for the assessment of Pain in subjects with Clinical conditions. However, there is no consensus about which type of QST is the best predictor of Clinical Pain responses. The purposes of this study were to determine: a) the QST measure with the strongest association with Clinical Pain intensity; and b) if the QST measure continued to predict Clinical Pain intensity in a model including relevant psychological factors. Fifty-nine patients seeking treatment for shoulder Pain underwent experimental Pain assessment involving heat and pressure stimuli. The patients also completed validated questionnaires for Pain intensity, Pain catastrophizing, anxiety, and depression. The 5th Pain rating in a series of suprathreshold heat Pain stimuli accounted for a significant amount of variance in Clinical Pain intensity, with no other QST measure contributing to the model. The 5th Pain rating remained a significant contributor to Clinical Pain intensity when psychological factors were included in the model. Furthermore, subjects with elevated 5th Pain rating, Pain catastrophizing, and depression scores had higher Clinical Pain intensity ratings in pre- and postoperative assessments. These data suggest that assessment of Pain should include suprathreshold heat stimuli and psychological factors separately, and a combination of these factors may be predictive of Pain intensity outcomes. Perspective The current study provides evidence for a suprathreshold heat Pain response as a Clinically relevant QST measure for patients with shoulder Pain, even after psychological factors were considered. The present findings suggest that the 5th Pain rating from a series of suprathreshold stimuli, Pain catastrophizing, and depression might play a role in predicting Pain intensity outcomes.

  • evidence for a biopsychosocial influence on shoulder Pain Pain catastrophizing and catechol o methyltransferase comt diplotype predict Clinical Pain ratings
    Pain, 2008
    Co-Authors: Steven Z George, Margaret R Wallace, Thomas W Wright, Michael W Moser, Warren H Greenfield, Brandon K Sack, Deborah M Herbstman, Roger B Fillingim
    Abstract:

    The experience of Pain is believed to be influenced by social, cultural, environmental, psychological, and genetic factors. Despite this assertion, few studies have included Clinically relevant Pain phenotypes when investigating interactions among these variables. This study investigated whether psychological variables specific to fear-avoidance models and catechol-O-methyltransferase (COMT) genotype influenced Pain ratings for a cohort of patients receiving operative treatment of shoulder Pain. Patients (n=58) completed questionnaires and had COMT genotype determined pre-operatively. Then, shoulder Pain ratings were collected 3-5 months post-operatively. This cohort consisted of 24 females and 34 males, with mean age of 50.3 (SD=15.0) and pre-operative Pain rating of 4.5/10 (SD=1.8). The frequency of COMT diplotypes was 34 with "high COMT activity" (LPS group) and 24 with "low COMT activity" (APS/HPS group). Preliminary analysis indicated that of all the fear-avoidance variables considered (fear of Pain, kinesiophobia, Pain catastrophizing, and anxiety), only Pain catastrophizing was a unique contributor to Clinical Pain ratings. A hierarchical regression model indicated that an interaction between Pain catastrophizing and COMT diplotype contributed additional variance in pre-operative Pain ratings. The Pain catastrophizingxCOMT diplotype interaction demonstrated predictive validity as patients with high Pain catastrophizing and low COMT activity (APS/HPS group) were more likely (RR=6.8, 95% CI=2.8-16.7) to have post-operative Pain ratings of 4.0/10 or higher. Our findings suggest that an interaction between Pain catastrophizing and COMT diplotype has the potential to influence Pain ratings in patients seeking operative treatment of their shoulder Pain.

  • fear of Pain influences outcomes after exercise induced delayed onset muscle soreness at the shoulder
    The Clinical Journal of Pain, 2007
    Co-Authors: Steven Z George, Geoffrey C Dover, Roger B Fillingim
    Abstract:

    Objectives: This study investigated whether anxiety, fear of Pain, or Pain catastrophizing were predictive of Pain-related outcomes after induced delayed onset muscle soreness (DOMS) at the shoulder. Methods: Healthy participants (19 males and 23 females) were eligible for participation if they had (a) no history of neck or shoulder Pain, (b) no sensory or motor impairments of the upper-extremity, (c) not regularly participating in upper-extremity weight training, (d) not currently or regularly taking Pain medication, and (e) no history of upper-extremity surgery. Participants completed self-report measures for fear of Pain, Pain catastrophizing, and anxiety. Then, participants underwent a standard fatigue protocol to induce DOMS in the shoulder external rotator muscles. Participants were reassessed 24 hours after DOMS induction on Clinical and evoked pressure Pain reports, muscle force production, self-report of upper-extremity disability, and kinesiophobia. Stepwise regression models considered sex, anxiety, Pain intensity, fear of Pain, and Pain catastrophizing as outcome predictors. Results: Fear of Pain alone explained 16% (P = 0.008) of the variance in Clinical Pain and 10% (P = 0.047) evoked pressure Pain intensity. Clinical Pain intensity alone explained 11% (P < 0.031) of the variance in muscle force production. Clinical Pain intensity and fear of Pain explained 50% (P < 0.001) of the variance in upper-extremity disability, whereas fear of Pain and sex accounted for 26% (P= 0.005) of the variance in kinesiophobia. Conclusions: With the exception of muscle force production, fear of Pain had a consistent influence on shoulder DOMS outcomes, even after controlling for Pain intensity. This study suggests fear of Pain may be a relevant psychologic factor to consider in Clinical studies investigating the development and treatment of chronic shoulder Pain.

  • fear of Pain influences outcomes after exercise induced delayed onset muscle soreness at the shoulder
    The Clinical Journal of Pain, 2007
    Co-Authors: Steven Z George, Geoffrey C Dover, Roger B Fillingim
    Abstract:

    Objectives This study investigated whether anxiety, fear of Pain, or Pain catastrophizing were predictive of Pain-related outcomes after induced delayed onset muscle soreness (DOMS) at the shoulder. Methods Healthy participants (19 males and 23 females) were eligible for participation if they had (a) no history of neck or shoulder Pain, (b) no sensory or motor impairments of the upper-extremity, (c) not regularly participating in upper-extremity weight training, (d) not currently or regularly taking Pain medication, and (e) no history of upper-extremity surgery. Participants completed self-report measures for fear of Pain, Pain catastrophizing, and anxiety. Then, participants underwent a standard fatigue protocol to induce DOMS in the shoulder external rotator muscles. Participants were reassessed 24 hours after DOMS induction on Clinical and evoked pressure Pain reports, muscle force production, self-report of upper-extremity disability, and kinesiophobia. Stepwise regression models considered sex, anxiety, Pain intensity, fear of Pain, and Pain catastrophizing as outcome predictors. Results Fear of Pain alone explained 16% (P=0.008) of the variance in Clinical Pain and 10% (P=0.047) evoked pressure Pain intensity. Clinical Pain intensity alone explained 11% (P Conclusions With the exception of muscle force production, fear of Pain had a consistent influence on shoulder DOMS outcomes, even after controlling for Pain intensity. This study suggests fear of Pain may be a relevant psychologic factor to consider in Clinical studies investigating the development and treatment of chronic shoulder Pain.

  • fear avoidance beliefs and temporal summation of evoked thermal Pain influence self report of disability in patients with chronic low back Pain
    Journal of Occupational Rehabilitation, 2006
    Co-Authors: Steven Z George, Roger B Fillingim, Virgil T Wittmer, Michael E Robinson
    Abstract:

    Introduction: Quantitative sensory testing has demonstrated a promising link between experimentally determined Pain sensitivity and Clinical Pain. However, previous studies of quantitative sensory testing have not routinely considered the important influence of psychological factors on Clinical Pain. This study investigated whether measures of thermal Pain sensitivity (temporal summation, first pulse response, and tolerance) contributed to Clinical Pain reports for patients with chronic low back Pain, after controlling for depression or fear-avoidance beliefs about work. Method: Consecutive patients (n=27) with chronic low back Pain were recruited from an interdisciplinary Pain rehabilitation program in Jacksonville, FL. Patients completed validated self-report questionnaires for depression, fear-avoidance beliefs, Clinical Pain intensity, and Clinical Pain related disability. Patients also underwent quantitative sensory testing from previously described protocols to determine thermal Pain sensitivity (temporal summation, first pulse response, and tolerance). Hierarchical regression models investigated the contribution of depression and thermal Pain sensitivity to Clinical Pain intensity, and fear-avoidance beliefs and thermal Pain sensitivity to Clinical Pain related disability. Results: None of the measures of thermal Pain sensitivity contributed to Clinical Pain intensity after controlling for depression. Temporal summation of evoked thermal Pain significantly contributed to Clinical Pain disability after controlling for fear-avoidance beliefs about work. Conclusion: Measures of thermal Pain sensitivity did not contribute to Pain intensity, after controlling for depression. Fear-avoidance beliefs about work and temporal summation of evoked thermal Pain significantly influenced Pain related disability. These factors should be considered as potential outcome predictors for patients with work-related low back Pain. Signifance: This study supported the neuromatrix theory of Pain for patients with CLBP, as cognitive-evaluative factor contributed to Pain perception, and cognitive-evaluative and sensory-discriminative factors uniquely contributed to an action program in response to chronic Pain. Future research will determine if a predictive model consisting of fear-avoidance beliefs and temporal summation of evoked thermal Pain has predictive validity for determining Clinical outcome in rehabilitation or vocational settings.

Roland Staud - One of the best experts on this subject based on the ideXlab platform.

  • resilience Pain and the brain relationships differ by sociodemographics
    Journal of Neuroscience Research, 2021
    Co-Authors: Jared J Tanner, Roland Staud, Alisa J Johnson, Ellen L Terry, Josue S Cardoso, Cynthia Garvan, Georg Deutsch, Hrishikesh Deshpande, Song Lai, Adriana S Addison
    Abstract:

    Chronic musculoskeletal (MSK) Pain is disabling to individuals and burdensome to society. A relationship between telomere length and resilience was reported in individuals with consideration for chronic Pain intensity. While chronic Pain associates with brain changes, little is known regarding the neurobiological interface of resilience. In a group of individuals with chronic MSK Pain, we examined the relationships between a previously investigated resilience index, Clinical Pain and functioning measures, and Pain-related brain structures, with consideration for sex and ethnicity/race. A cross-sectional analysis of 166 non-Hispanic Black and non-Hispanic White adults, 45-85 years of age with Pain ≥ 1 body site (s) over the past 3 months was completed. Measures of Clinical Pain and functioning, biobehavioral and psychosocial resilience, and structural MRI were completed. Our findings indicate higher levels of resilience associate with lower levels of Clinical Pain and functional limitations. Significant associations between resilience, ethnicity/race, and/or sex, and Pain-related brain gray matter structure were demonstrated in the right amygdaloid complex, bilateral thalamus, and postcentral gyrus. Our findings provide compelling evidence that in order to decipher the neurobiological code of chronic Pain and related protective factors, it will be important to improve how chronic Pain is phenotyped; to include an equal representation of females in studies including analyses stratifying by sex, and to consider other sociodemographic factors.

  • effects of milnacipran on Clinical Pain and hyperalgesia of patients with fibromyalgia results of a 6 week randomized controlled trial
    The Journal of Pain, 2015
    Co-Authors: Roland Staud, Donald D. Price, Yesenia E Lucas, Michael E Robinson
    Abstract:

    Abstract Milnacipran is a serotonin-norepinephrine reuptake inhibitor that was approved by the U.S. Food and Drug Administration as effective therapy for fibromyalgia (FM) symptoms. However, its analgesic mechanism of action is not well understood. We hypothesized that improvement of mechanical and heat hyperalgesia would be a critical component of overall milnacipran efficacy in FM. We used a novel quantitative sensory testing protocol for assessment of mechanical and heat Pain sensitivity that can be used for testing of peripheral and central Pain mechanisms and their impact on Clinical Pain over time. We applied tonic mechanical and heat Pain stimuli to 46 patients with FM during a randomized controlled trial with either 50 mg milnacipran (n = 23) or placebo (n = 23) twice daily over 6 weeks. During this trial, mean Clinical Pain (standard deviation) was evaluated daily, and mechanical and heat Pain sensitivity every 2 weeks. At study entry, Clinical Pain was 5.0 (1.8) and 5.5 (1.8) visual analog scale units for patients with FM randomized to placebo and milnacipran, respectively ( P  > .05). Over 6 weeks, Clinical Pain of patients with FM significantly declined by 15%, but this improvement was not statistically different between milnacipran and placebo. However, repeated measures of mechanical and heat Pain sensitivity reliably predicted up to 80% of the variance in Clinical FM Pain at every time point. Clinical Pain and mechanical/heat Pain sensitivity of patients with FM steadily declined during this trial, but the effects of milnacipran were not found to be superior to placebo. Repeated measures of mechanical/heat hyperalgesia reliably predicted large amounts of the variance in Clinical Pain across all participants, indicating their relevance for FM Pain. Perspective Although Clinical Pain and hyperalgesia decreased during this 6-week trial, the efficacy of milnacipran was not superior to placebo. The high correlations between Clinical Pain and hyperalgesia ratings at every time point seem to emphasize the relevant contributions of mechanical and heat hyperalgesia to Clinical FM Pain.

  • analgesic and anti hyperalgesic effects of muscle injections with lidocaine or saline in patients with fibromyalgia syndrome
    European Journal of Pain, 2014
    Co-Authors: Roland Staud, Donald D. Price, Elizabeth E Weyl, Emily J Bartley, Michael E Robinson
    Abstract:

    Background Patients with musculoskeletal Pain syndrome including fibromyalgia (FM) complain of chronic Pain from deep tissues including muscles. Previous research suggests the relevance of impulse input from deep tissues for Clinical FM Pain. We hypothesized that blocking abnormal impulse input with intramuscular lidocaine would decrease primary and secondary hyperalgesia and FM patients’ Clinical Pain.

  • temporal summation of Pain as a prospective predictor of Clinical Pain severity in adults aged 45 years and older with knee osteoarthritis ethnic differences
    Psychosomatic Medicine, 2014
    Co-Authors: Burel R Goodin, Yenisel Cruzalmeida, Hailey W Bulls, Matthew S Herbert, J Schmidt, Christopher D King, Toni L Glover, Adriana Sotolongo, Kimberly T Sibille, Roland Staud
    Abstract:

    Objective Enhanced Pain facilitation is reportedly an important contributor to the Clinical Pain experiences of individuals with knee osteoarthritis (OA). Ethnic differences in the prevalence and severity of knee OA in addition to associated Pain are also well documented. Temporal summation (TS) of Pain is a widely applicable quantitative sensory testing method that invokes neural mechanisms related to Pain facilitatory processes. This study tested whether TS of Pain, an index of Pain facilitation, differentially predicts the Clinical Pain experiences of African Americans and non-Hispanic Whites with symptomatic knee OA.

  • slow temporal summation of Pain for assessment of central Pain sensitivity and Clinical Pain of fibromyalgia patients
    PLOS ONE, 2014
    Co-Authors: Roland Staud, Elizabeth E Weyl, Joseph L Riley, Roger B Fillingim
    Abstract:

    Background In healthy individuals slow temporal summation of Pain or wind-up (WU) can be evoked by repetitive heat-pulses at frequencies of ≥.33 Hz. Previous WU studies have used various stimulus frequencies and intensities to characterize central sensitization of human subjects including fibromyalgia (FM) patients. However, many trials demonstrated considerable WU-variability including zero WU or even wind-down (WD) at stimulus intensities sufficient for activating C-nociceptors. Additionally, few WU-protocols have controlled for contributions of individual Pain sensitivity to WU-magnitude, which is critical for WU-comparisons. We hypothesized that integration of 3 different WU-trains into a single WU-response function (WU-RF) would not only control for individuals’ Pain sensitivity but also better characterize their central Pain responding including WU and WD. Methods 33 normal controls (NC) and 38 FM patients participated in a study of heat-WU. We systematically varied stimulus intensities of.4 Hz heat-pulse trains applied to the hands. Pain summation was calculated as difference scores of 1st and 5th heat-pulse ratings. WU-difference (WU-Δ) scores related to 3 heat-pulse trains (44°C, 46°C, 48°C) were integrated into WU-response functions whose slopes were used to assess group differences in central Pain sensitivity. WU-aftersensations (WU-AS) at 15 s and 30 s were used to predict Clinical FM Pain intensity. Results WU-Δ scores linearly accelerated with increasing stimulus intensity (p NC) from WD to WU. Slope of WU-RF, which is representative of central Pain sensitivity, was significantly steeper in FM patients than NC (p<.003). WU-AS predicted Clinical FM Pain intensity (Pearson’s r = .4; p<.04). Conclusions Compared to single WU series, WU-RFs integrate individuals’ Pain sensitivity as well as WU and WD. Slope of WU-RFs was significantly different between FM patients and NC. Therefore WU-RF may be useful for assessing central sensitization of chronic Pain patients in research and Clinical practice.

Michael E Robinson - One of the best experts on this subject based on the ideXlab platform.

  • effects of milnacipran on Clinical Pain and hyperalgesia of patients with fibromyalgia results of a 6 week randomized controlled trial
    The Journal of Pain, 2015
    Co-Authors: Roland Staud, Donald D. Price, Yesenia E Lucas, Michael E Robinson
    Abstract:

    Abstract Milnacipran is a serotonin-norepinephrine reuptake inhibitor that was approved by the U.S. Food and Drug Administration as effective therapy for fibromyalgia (FM) symptoms. However, its analgesic mechanism of action is not well understood. We hypothesized that improvement of mechanical and heat hyperalgesia would be a critical component of overall milnacipran efficacy in FM. We used a novel quantitative sensory testing protocol for assessment of mechanical and heat Pain sensitivity that can be used for testing of peripheral and central Pain mechanisms and their impact on Clinical Pain over time. We applied tonic mechanical and heat Pain stimuli to 46 patients with FM during a randomized controlled trial with either 50 mg milnacipran (n = 23) or placebo (n = 23) twice daily over 6 weeks. During this trial, mean Clinical Pain (standard deviation) was evaluated daily, and mechanical and heat Pain sensitivity every 2 weeks. At study entry, Clinical Pain was 5.0 (1.8) and 5.5 (1.8) visual analog scale units for patients with FM randomized to placebo and milnacipran, respectively ( P  > .05). Over 6 weeks, Clinical Pain of patients with FM significantly declined by 15%, but this improvement was not statistically different between milnacipran and placebo. However, repeated measures of mechanical and heat Pain sensitivity reliably predicted up to 80% of the variance in Clinical FM Pain at every time point. Clinical Pain and mechanical/heat Pain sensitivity of patients with FM steadily declined during this trial, but the effects of milnacipran were not found to be superior to placebo. Repeated measures of mechanical/heat hyperalgesia reliably predicted large amounts of the variance in Clinical Pain across all participants, indicating their relevance for FM Pain. Perspective Although Clinical Pain and hyperalgesia decreased during this 6-week trial, the efficacy of milnacipran was not superior to placebo. The high correlations between Clinical Pain and hyperalgesia ratings at every time point seem to emphasize the relevant contributions of mechanical and heat hyperalgesia to Clinical FM Pain.

  • analgesic and anti hyperalgesic effects of muscle injections with lidocaine or saline in patients with fibromyalgia syndrome
    European Journal of Pain, 2014
    Co-Authors: Roland Staud, Donald D. Price, Elizabeth E Weyl, Emily J Bartley, Michael E Robinson
    Abstract:

    Background Patients with musculoskeletal Pain syndrome including fibromyalgia (FM) complain of chronic Pain from deep tissues including muscles. Previous research suggests the relevance of impulse input from deep tissues for Clinical FM Pain. We hypothesized that blocking abnormal impulse input with intramuscular lidocaine would decrease primary and secondary hyperalgesia and FM patients’ Clinical Pain.

  • mechanical and heat hyperalgesia highly predict Clinical Pain intensity in patients with chronic musculoskeletal Pain syndromes
    The Journal of Pain, 2012
    Co-Authors: Roland Staud, Donald D. Price, Elizabeth E Weyl, Michael E Robinson
    Abstract:

    Abstract Multiple abnormalities in Pain processing have been reported in patients with chronic musculoskeletal Pain syndromes. These changes include mechanical and thermal hyperalgesia, decreased thresholds to mechanical and thermal stimuli (allodynia), and central sensitization, all of which are fundamental to the generation of Clinical Pain. Therefore, we hypothesized that quantitative sensory tests may provide useful predictors of Clinical Pain intensity of such patients. Our previous studies of fibromyalgia (FM) patients have shown statistically significant correlations of quantitative sensory test results with Clinical Pain intensity, including mechanical spatial summation, number of Pain areas, wind-up, and wind-up aftersensations. Although these tests predicted up to 59% of the variance in FM Clinical Pain intensity, their expense and technical complexities limited widespread use in Clinical practice and trials. Thus, we developed practical tests of primary (mechanical) and secondary (heat) hyperalgesia that also strongly predict Clinical Pain intensity in patients with chronic musculoskeletal Pain disorders. Thirty-six individuals with FM, 24 with local musculoskeletal Pain, and 23 normal controls underwent testing of mechanical and heat hyperalgesia at the shoulders and hands. All subjects rated experimental Pains using an electronic visual analog scale. Using either heat or pressure Pain ratings as well as tender point counts and negative affect as predictors, up to 49.4% of the patients' variance of Clinical Pain intensity could be estimated. Results of this study emphasize the important contributions of peripheral and central factors to both local and widespread chronic Pain. Overall, measures of mechanical and heat hyperalgesia in combination with tender point and negative affect provided powerful predictors of Clinical Pain intensity in chronic musculoskeletal Pain patients that can be readily used in Clinical practice and trials. Perspective Simple tests of mechanical and heat hyperalgesia can predict large proportions of the variance in Clinical Pain intensity of chronic musculoskeletal Pain patients and thus are feasible to be included in Clinical practice and Clinical trials.

  • Pain variability in fibromyalgia is related to activity and rest role of peripheral tissue impulse input
    The Journal of Pain, 2010
    Co-Authors: Roland Staud, Michael E Robinson, Elizabeth E Weyl, Donald D. Price
    Abstract:

    Abstract Because fibromyalgia (FM) patients frequently report activity-dependent deep tissue Pains, impulse input from Painful body regions may be relevant for their musculoskeletal complaints. In addition, peripheral impulse input may induce and maintain thermal and mechanical hyperalgesia of FM patients. If so, activity and rest may alternately enhance and diminish intensity of FM Pain. However, the effects of exercise on Pain are ambiguous in studies of FM. Whereas exercise-only studies demonstrated increased Pain and hyperalgesia during and after physical activity, some exercise studies that included rest periods resulted in decreased FM Pain and increased function. To further clarify these effects, we examined the effects of alternating exercise with rest on Clinical Pain and thermal/mechanical hyperalgesia of 34 FM patients and 36 age-matched healthy controls (NC). Using an ergometer, all subjects performed arm exercise to exhaustion twice alternating with 15-minute rest periods. Although strenuous muscle activity was reported as Painful by most FM subjects, overall Clinical Pain consistently decreased during the rest periods. Additionally, FM subjects' Pain sensitivity to mechanical pressure decreased after each exercise and rest session. Conclusion: Alternating strenuous exercise with brief rest periods not only decreased overall Clinical Pain of FM subjects but also their mechanical hyperalgesia. No prolonged worsening of overall FM Pain and hyperalgesia occurred despite vigorous muscle activity. Our findings contribute further evidence that FM Pain and hyperalgesia are at least partially maintained by muscle impulse input, and that some types of exercises may be beneficial for FM. Perspective FM is a Pain-amplification syndrome that depends at least in part on peripheral tissue impulse input. Whereas muscle activity increased overall Pain, short rest periods produced analgesic effects.

  • fear avoidance beliefs and temporal summation of evoked thermal Pain influence self report of disability in patients with chronic low back Pain
    Journal of Occupational Rehabilitation, 2006
    Co-Authors: Steven Z George, Roger B Fillingim, Virgil T Wittmer, Michael E Robinson
    Abstract:

    Introduction: Quantitative sensory testing has demonstrated a promising link between experimentally determined Pain sensitivity and Clinical Pain. However, previous studies of quantitative sensory testing have not routinely considered the important influence of psychological factors on Clinical Pain. This study investigated whether measures of thermal Pain sensitivity (temporal summation, first pulse response, and tolerance) contributed to Clinical Pain reports for patients with chronic low back Pain, after controlling for depression or fear-avoidance beliefs about work. Method: Consecutive patients (n=27) with chronic low back Pain were recruited from an interdisciplinary Pain rehabilitation program in Jacksonville, FL. Patients completed validated self-report questionnaires for depression, fear-avoidance beliefs, Clinical Pain intensity, and Clinical Pain related disability. Patients also underwent quantitative sensory testing from previously described protocols to determine thermal Pain sensitivity (temporal summation, first pulse response, and tolerance). Hierarchical regression models investigated the contribution of depression and thermal Pain sensitivity to Clinical Pain intensity, and fear-avoidance beliefs and thermal Pain sensitivity to Clinical Pain related disability. Results: None of the measures of thermal Pain sensitivity contributed to Clinical Pain intensity after controlling for depression. Temporal summation of evoked thermal Pain significantly contributed to Clinical Pain disability after controlling for fear-avoidance beliefs about work. Conclusion: Measures of thermal Pain sensitivity did not contribute to Pain intensity, after controlling for depression. Fear-avoidance beliefs about work and temporal summation of evoked thermal Pain significantly influenced Pain related disability. These factors should be considered as potential outcome predictors for patients with work-related low back Pain. Signifance: This study supported the neuromatrix theory of Pain for patients with CLBP, as cognitive-evaluative factor contributed to Pain perception, and cognitive-evaluative and sensory-discriminative factors uniquely contributed to an action program in response to chronic Pain. Future research will determine if a predictive model consisting of fear-avoidance beliefs and temporal summation of evoked thermal Pain has predictive validity for determining Clinical outcome in rehabilitation or vocational settings.

Donald D. Price - One of the best experts on this subject based on the ideXlab platform.

  • effects of milnacipran on Clinical Pain and hyperalgesia of patients with fibromyalgia results of a 6 week randomized controlled trial
    The Journal of Pain, 2015
    Co-Authors: Roland Staud, Donald D. Price, Yesenia E Lucas, Michael E Robinson
    Abstract:

    Abstract Milnacipran is a serotonin-norepinephrine reuptake inhibitor that was approved by the U.S. Food and Drug Administration as effective therapy for fibromyalgia (FM) symptoms. However, its analgesic mechanism of action is not well understood. We hypothesized that improvement of mechanical and heat hyperalgesia would be a critical component of overall milnacipran efficacy in FM. We used a novel quantitative sensory testing protocol for assessment of mechanical and heat Pain sensitivity that can be used for testing of peripheral and central Pain mechanisms and their impact on Clinical Pain over time. We applied tonic mechanical and heat Pain stimuli to 46 patients with FM during a randomized controlled trial with either 50 mg milnacipran (n = 23) or placebo (n = 23) twice daily over 6 weeks. During this trial, mean Clinical Pain (standard deviation) was evaluated daily, and mechanical and heat Pain sensitivity every 2 weeks. At study entry, Clinical Pain was 5.0 (1.8) and 5.5 (1.8) visual analog scale units for patients with FM randomized to placebo and milnacipran, respectively ( P  > .05). Over 6 weeks, Clinical Pain of patients with FM significantly declined by 15%, but this improvement was not statistically different between milnacipran and placebo. However, repeated measures of mechanical and heat Pain sensitivity reliably predicted up to 80% of the variance in Clinical FM Pain at every time point. Clinical Pain and mechanical/heat Pain sensitivity of patients with FM steadily declined during this trial, but the effects of milnacipran were not found to be superior to placebo. Repeated measures of mechanical/heat hyperalgesia reliably predicted large amounts of the variance in Clinical Pain across all participants, indicating their relevance for FM Pain. Perspective Although Clinical Pain and hyperalgesia decreased during this 6-week trial, the efficacy of milnacipran was not superior to placebo. The high correlations between Clinical Pain and hyperalgesia ratings at every time point seem to emphasize the relevant contributions of mechanical and heat hyperalgesia to Clinical FM Pain.

  • analgesic and anti hyperalgesic effects of muscle injections with lidocaine or saline in patients with fibromyalgia syndrome
    European Journal of Pain, 2014
    Co-Authors: Roland Staud, Donald D. Price, Elizabeth E Weyl, Emily J Bartley, Michael E Robinson
    Abstract:

    Background Patients with musculoskeletal Pain syndrome including fibromyalgia (FM) complain of chronic Pain from deep tissues including muscles. Previous research suggests the relevance of impulse input from deep tissues for Clinical FM Pain. We hypothesized that blocking abnormal impulse input with intramuscular lidocaine would decrease primary and secondary hyperalgesia and FM patients’ Clinical Pain.

  • mechanical and heat hyperalgesia highly predict Clinical Pain intensity in patients with chronic musculoskeletal Pain syndromes
    The Journal of Pain, 2012
    Co-Authors: Roland Staud, Donald D. Price, Elizabeth E Weyl, Michael E Robinson
    Abstract:

    Abstract Multiple abnormalities in Pain processing have been reported in patients with chronic musculoskeletal Pain syndromes. These changes include mechanical and thermal hyperalgesia, decreased thresholds to mechanical and thermal stimuli (allodynia), and central sensitization, all of which are fundamental to the generation of Clinical Pain. Therefore, we hypothesized that quantitative sensory tests may provide useful predictors of Clinical Pain intensity of such patients. Our previous studies of fibromyalgia (FM) patients have shown statistically significant correlations of quantitative sensory test results with Clinical Pain intensity, including mechanical spatial summation, number of Pain areas, wind-up, and wind-up aftersensations. Although these tests predicted up to 59% of the variance in FM Clinical Pain intensity, their expense and technical complexities limited widespread use in Clinical practice and trials. Thus, we developed practical tests of primary (mechanical) and secondary (heat) hyperalgesia that also strongly predict Clinical Pain intensity in patients with chronic musculoskeletal Pain disorders. Thirty-six individuals with FM, 24 with local musculoskeletal Pain, and 23 normal controls underwent testing of mechanical and heat hyperalgesia at the shoulders and hands. All subjects rated experimental Pains using an electronic visual analog scale. Using either heat or pressure Pain ratings as well as tender point counts and negative affect as predictors, up to 49.4% of the patients' variance of Clinical Pain intensity could be estimated. Results of this study emphasize the important contributions of peripheral and central factors to both local and widespread chronic Pain. Overall, measures of mechanical and heat hyperalgesia in combination with tender point and negative affect provided powerful predictors of Clinical Pain intensity in chronic musculoskeletal Pain patients that can be readily used in Clinical practice and trials. Perspective Simple tests of mechanical and heat hyperalgesia can predict large proportions of the variance in Clinical Pain intensity of chronic musculoskeletal Pain patients and thus are feasible to be included in Clinical practice and Clinical trials.

  • Pain variability in fibromyalgia is related to activity and rest role of peripheral tissue impulse input
    The Journal of Pain, 2010
    Co-Authors: Roland Staud, Michael E Robinson, Elizabeth E Weyl, Donald D. Price
    Abstract:

    Abstract Because fibromyalgia (FM) patients frequently report activity-dependent deep tissue Pains, impulse input from Painful body regions may be relevant for their musculoskeletal complaints. In addition, peripheral impulse input may induce and maintain thermal and mechanical hyperalgesia of FM patients. If so, activity and rest may alternately enhance and diminish intensity of FM Pain. However, the effects of exercise on Pain are ambiguous in studies of FM. Whereas exercise-only studies demonstrated increased Pain and hyperalgesia during and after physical activity, some exercise studies that included rest periods resulted in decreased FM Pain and increased function. To further clarify these effects, we examined the effects of alternating exercise with rest on Clinical Pain and thermal/mechanical hyperalgesia of 34 FM patients and 36 age-matched healthy controls (NC). Using an ergometer, all subjects performed arm exercise to exhaustion twice alternating with 15-minute rest periods. Although strenuous muscle activity was reported as Painful by most FM subjects, overall Clinical Pain consistently decreased during the rest periods. Additionally, FM subjects' Pain sensitivity to mechanical pressure decreased after each exercise and rest session. Conclusion: Alternating strenuous exercise with brief rest periods not only decreased overall Clinical Pain of FM subjects but also their mechanical hyperalgesia. No prolonged worsening of overall FM Pain and hyperalgesia occurred despite vigorous muscle activity. Our findings contribute further evidence that FM Pain and hyperalgesia are at least partially maintained by muscle impulse input, and that some types of exercises may be beneficial for FM. Perspective FM is a Pain-amplification syndrome that depends at least in part on peripheral tissue impulse input. Whereas muscle activity increased overall Pain, short rest periods produced analgesic effects.

  • ratings of experimental Pain and Pain related negative affect predict Clinical Pain in patients with fibromyalgia syndrome
    Pain, 2003
    Co-Authors: Roland Staud, Michael E Robinson, Charles J Vierck, Richard C Cannon, Andre P Mauderli, Donald D. Price
    Abstract:

    Abstract Patients with fibromyalgia syndrome (FMS) report chronic Pain related to abnormal sensitivity of muscles that is reflected by so-called tender points (TP). TP represent areas of abnormal mechanical Pain thresholds that have only shown a minor correlation with Clinical Pain of FMS patients and seem to be better suited for predicting distress. Pain-related negative affect (PRNA), abnormal temporal summation of second Pain (termed wind-up or WU), and abnormal WU decay are frequently present in FMS patients. WU and WU decay can provide measures of central sensitization, which may contribute to Clinical FMS Pain. We therefore investigated the role of WU, WU decay, TP count, and PRNA as predictors of Clinical Pain in FMS subjects. Fifty-five FMS subjects rated their Clinical Pain at entry into the study using a visual analogue scale (VAS). After a TP evaluation, all subjects received two trials of thermal WU and WU decay testing. Hierarchical regression analysis demonstrated that the combination of PRNA ratings, TP count, and WU decay ratings predicted 49.7% of the variance of Clinical Pain in FMS. This model demonstrates independent relationships of biological and psychological factors to Clinical Pain and underscores the important role of abnormal peripheral and central Pain mechanisms for FMS. Therefore, the combination of PRNA, TP count, and WU decay may provide an excellent measure for future Clinical studies of FMS patients.