Heritability of Pain Catastrophizing and Associations with Experimental Pain Outcomes: A Twin Study
Trost, Zina; Strachan, Eric; Sullivan, Michael; Vervoort, Tine; Avery, Ally R.; Afari, Niloofar
2014-01-01
The current study employed a twin paradigm to examine the genetic and environmental contributions to pain catastrophizing as well as the observed association between pain catastrophizing and cold pressor task (CPT) outcomes. Male and female monozygotic (n=206) and dizygotic twins (n=194) from the University of Washington Twin Registry completed a measure of pain catastrophizing and performed a CPT challenge. As expected, pain catastrophizing emerged as a significant predictor of several CPT outcomes, including cold pressor immersion tolerance, pain tolerance, and delayed pain rating. The heritability estimate for pain catastrophizing was found to be 37% with the remaining 63% of variance attributable to unique environmental influence. Additionally, the observed associations between pain catastrophizing and CPT outcomes were not found attributable to shared genetics or environmental exposure, suggesting a direct relationship between catastrophizing and experimental pain outcomes. This study is the first to examine the heritability of pain catastrophizing and potential processes by which pain catastrophizing is related to experimental pain response. PMID:25599234
Alabas, O A; Tashani, O A; Johnson, M I
2013-05-01
Gender role expectations of pain (GREP) have been shown to mediate sex differences in experimental pain. Few studies have investigated the role of ethnicity in shaping GREP. The aim of this study was to examine interactions between ethnicity and GREP on experimentally induced pressure and ischaemic pain in Libyan and white British students in their respective countries. Libyan (n = 124) and white British (n = 51) students completed a GREP questionnaire and their response to experimental pain was measured. Blunt pressure pain threshold (PPT) was measured over the 1st interosseous muscle using algometry. Pain intensity and pain unpleasantness (100 mm visual analogue scale) were measured at 1-min intervals during a submaximal effort tourniquet test on the forearm. Multivariate analysis of variance detected significant effects for Sex and Ethnicity on pain measurements. Men had higher PPTs than women (p < 0.001). Libyans had higher PPTs than white British participants (p < 0.001). There were significant effects for Sex and Ethnicity for pain intensity ratings (p < 0.01) but no significant differences between the sexes in pain unpleasantness (p > 0.05). Libyan participants had higher pain intensity (p < 0.01) and pain unpleasantness (p < 0.05) ratings compared with white British participants. There were effects for Sex and Ethnicity for all GREP dimensions. Libyan participants exhibited stronger stereotypical views in GREP than white British participants (p < 0.001). GREP was the mediator of sex but not ethnic differences in pain report, suggesting that gender stereotypical attitudes to pain account for differences in pain expression between men and women. © 2012 European Federation of International Association for the Study of Pain Chapters.
The role of pain catastrophizing in experimental pain perception.
Kristiansen, Frederik L; Olesen, Anne E; Brock, Christina; Gazerani, Parisa; Petrini, Laura; Mogil, Jeffrey S; Drewes, Asbjørn M
2014-03-01
Pain is a subjective experience influenced by multiple factors, and tremendous variety within individuals is present. To evaluate emotional state of pain, catastrophizing score can be used. This study investigated pain catastrophizing ratings in association with experimental pain perception. Experimental pain was induced using thermal heat and cold stimulation of skin, mechanical stimulation of muscle and bone, and thermal, mechanical, and electrical stimulation of the gastrointestinal tract in healthy participants (N = 41). Prior to experimental sessions, a pain catastrophizing questionnaire was filled out by each participant. Based on the median catastophizing score, participants were divided into two groups: noncatastrophizers and low-catastrophizers. No significant difference was found between low-catastrophizers and noncatastrophizers in thermal heat stimulation of skin, mechanical stimulation of muscle and bone, and rectal electrical stimulation (All P > 0.05). Low-catastrophizers were more sensitive to visceral thermal stimulation (4.7%, P = 0.02) and visceral mechanical stimulation (29.7%, P = 0.03). For participants that completed the 120 seconds ice water stimulation, noncatastrophizers reported 13.8% less pain than low-catastrophizers (P = 0.02). A positive correlation between PCS score and pain perception on cold pressor test was found (r = 0.4, P = 0.02). By extrapolating data, further analysis of the total group was performed and no differences (both P > 0.05) were observed. Even small increments in pain catastrophizing score can influence pain perception to deep and tonic stimulations. Catatrophizing may partly explain the variability found in experimental pain studies. © 2013 World Institute of Pain.
Gender role expectations of pain: relationship to experimental pain perception
Wise, Emily A.; Price, Donald D.; Myers, Cynthia D.; Heft, Marc W.; Robinson, Michael E.
2008-01-01
The primary purpose of this study was to investigate the influence of an individual’s Gender Role Expectations of Pain (GREP) on experimental pain report. One hundred and forty-eight subjects (87 females and 61 males) subjects underwent thermal testing and were asked to report pain threshold, pain tolerance, VAS ratings of pain intensity and unpleasantness, and a computerized visual analogue scales (VAS) rating of pain intensity during the procedure. Subjects completed the GREP questionnaire to assess sex-related stereotypic attributions of pain sensitivity, pain endurance, and willingness to report pain. Consistent with previous research, significant sex differences emerged for measures of pain threshold, pain tolerance, and pain unpleasantness. After statistically controlling for age, GREP scores were significant predictors of threshold, tolerance, and pain unpleasantness, accounting for an additional 7, 11, and 21% of the variance, respectively. Sex remained a significant predictor of pain tolerance in hierarchical regression analyses after controlling for GREP scores. Results provide support for two competing but not mutually exclusive hypotheses related to the sex differences in experimental pain. Both psychosocial factors and first-order, biological sex differences remain as viable explanations for differences in experimental pain report between the sexes. It appears that GREP do play a part in determining an individual’s pain report and may be contributing to the sex differences in the laboratory setting. PMID:11973007
Johansen, Aslak; Schirmer, Henrik; Stubhaug, Audun; Nielsen, Christopher S
2014-02-01
In a large survey incorporating medical examination (N=12,981), information on chronic pain and surgery was collected, and sensitivity to different pain modalities was tested. Tolerance to the cold pressor test was analysed with survival statistics for 10,486 individuals, perceived cold pressor pain intensity was calculated for 10,367 individuals, heat pain threshold was assessed for 4,054 individuals, and pressure pain sensitivity for 4,689 individuals. Persistent post-surgical pain, defined by self-report, was associated with lower cold pressor tolerance (sex-adjusted hazard ratio=1.34, 95% confidence interval=1.08-1.66), but not when adjusting for other chronic pain. Other experimental pain modalities did not differentiate between individuals with or without post-surgical pain. Of the individuals with chronic pain (N=3352), 6.2% indicated surgery as a cause, although only 0.5% indicated surgery as the only cause. The associations found between persistent post-surgical pain and cold pressor tolerance is largely explained by the co-existence of chronic pain from other causes. We conclude that most cases of persistent post-surgical pain are coexistent with other chronic pain, and that, in an unselected post-surgical population, persistent post-surgical pain is not significantly associated with pain sensitivity when controlling for comorbid pain from other causes. A low prevalence of self-reported persistent pain from surgery attenuates statistically significant associations. We hypothesize that general chronic pain is associated with central changes in pain processing as expressed by reduced tolerance for the cold pressor test. Copyright © 2013 International Association for the Study of Pain. Published by Elsevier B.V. All rights reserved.
Sex Differences in Experimental and Clinical Pain Sensitivity for Patients with Shoulder Pain
Kindler, Lindsay L.; Valencia, Carolina; Fillingim, Roger B.; George, Steven Z.
2010-01-01
Previous research demonstrates that men and women differ in the way that they perceive and process pain. Much of this work has been done in healthy adults with a lack of consensus in clinical pain populations. The purpose of this study was to investigate how men and women with shoulder pain differ in their experience of experimental and clinical pain and whether psychological processes differentially affect these responses. Fifty nine consecutive subjects (24 women, 35 men) seeking operative treatment for shoulder pain were enrolled in this study. Subjects completed self report questionnaires to assess clinical pain, catastrophizing, anxiety and depression and underwent a series of experimental pain tests consisting of pressure pain, thermal pain (threshold and tolerance), and thermal temporal summation. Results indicated that women experienced greater clinical pain and enhanced sensitivity to pressure pain. Age did not affect the observed sex differences. There were no sex differences in psychological association with experimental and clinical pain in this cohort. The relationship between clinical and experimental pressure pain was stronger in women as compared to men. These findings offer insight into the interactions between biological and psychosocial influences of pain and how these interactions vary by sex. PMID:20598598
Bilateral experimental neck pain reorganize axioscapular muscle coordination and pain sensitivity.
Christensen, S W; Hirata, R P; Graven-Nielsen, T
2017-04-01
Neck pain is a large clinical problem where reorganized trunk and axioscapular muscle activities have been hypothesised contributing to pain persistence and pain hypersensitivity. This study investigated the effects of bilateral experimental neck pain on trunk and axioscapular muscle function and pain sensitivity. In 25 healthy volunteers, bilateral experimental neck pain was induced in the splenius capitis muscles by hypertonic saline injections. Isotonic saline was used as control. In sitting, subjects performed slow, fast and slow-resisted unilateral arm movements before, during and after injections. Electromyography (EMG) was recorded from eight shoulder and trunk muscles bilaterally. Pressure pain thresholds (PPTs) were assessed bilaterally at the neck, head and arm. Data were normalized to the before-measures. Compared with control and post measurements, experimental neck pain caused (1) decreased EMG activity of the ipsilateral upper trapezius muscles during all but slow-resisted down movements (p < 0.001), and (2) increased EMG activity in the ipsilateral erector spinae muscle during slow and fast movements (p < 0.02), and in the contralateral erector spinae muscle during all but fast up and slow-resisted down movements (p < 0.007). The PPTs in the painful condition increased at the head and arm compared with post measurements and the control condition (p < 0.001). In the post-pain condition, the neck PPT was decreased compared with the control condition (p < 0.001). Acute bilateral neck pain reorganized axioscapular and trunk muscle activity together with local hyperalgesia and widespread hypoalgesia indicating that acute neck pain immediately affects trunk and axioscapular function which may affect both assessment and treatment. Bilateral clinical neck pain alters axioscapular muscle coordination but only effects of unilateral experimental neck pain has been investigated. Bilateral experimental neck pain causes task-dependent reorganized
Mechanisms of Osteoarthritic Pain. Studies in Humans and Experimental Models
Eitner, Annett; Hofmann, Gunther O.; Schaible, Hans-Georg
2017-01-01
Pain due to osteoarthritis (OA) is one of the most frequent causes of chronic pain. However, the mechanisms of OA pain are poorly understood. This review addresses the mechanisms which are thought to be involved in OA pain, derived from studies on pain mechanisms in humans and in experimental models of OA. Three areas will be considered, namely local processes in the joint associated with OA pain, neuronal mechanisms involved in OA pain, and general factors which influence OA pain. Except the cartilage all structures of the joints are innervated by nociceptors. Although the hallmark of OA is the degradation of the cartilage, OA joints show multiple structural alterations of cartilage, bone and synovial tissue. In particular synovitis and bone marrow lesions have been proposed to determine OA pain whereas the contribution of the other pathologies to pain generation has been studied less. Concerning the peripheral neuronal mechanisms of OA pain, peripheral nociceptive sensitization was shown, and neuropathic mechanisms may be involved at some stages. Structural changes of joint innervation such as local loss and/or sprouting of nerve fibers were shown. In addition, central sensitization, reduction of descending inhibition, descending excitation and cortical atrophies were observed in OA. The combination of different neuronal mechanisms may define the particular pain phenotype in an OA patient. Among mediators involved in OA pain, nerve growth factor (NGF) is in the focus because antibodies against NGF significantly reduce OA pain. Several studies show that neutralization of interleukin-1β and TNF may reduce OA pain. Many patients with OA exhibit comorbidities such as obesity, low grade systemic inflammation and diabetes mellitus. These comorbidities can significantly influence the course of OA, and pain research just began to study the significance of such factors in pain generation. In addition, psychologic and socioeconomic factors may aggravate OA pain, and in
Reiner, Keren; Granot, Michal; Soffer, Eliran; Lipsitz, Joshua Dan
2016-04-01
Research shows that mindfulness meditation (MM) affects pain perception; however, studies have yet to measure patterns of change over time. We examined effects of MM on perception of experimental heat pain using multiple psychophysical indices, including pattern of change in response to tonic painful stimuli. We also tested the potential moderating role of baseline mindfulness. Forty participants were randomly assigned to a brief MM training or control group. We assessed: a) heat pain threshold (HPT), b) temperature which induces pain at a fixed, target intensity level, and c) response pattern over time to tonic heat pain. Compared to control group, the MM group showed increased HPT and more rapid attenuation of pain intensity for tonic pain stimuli. Moderation analyses indicated that baseline mindfulness moderated effects of MM on HPT. A brief MM intervention appears to affect perception of experimental pain both by increasing pain threshold and accelerating modulation of response. Findings may help elucidate mechanisms of MM for chronic pain. © 2015 American Academy of Pain Medicine. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.
Jørgensen, Tanja Schjødt; Henriksen, Marius; Rosager, Sara; Klokker, Louise; Ellegaard, Karen; Danneskiold-Samsøe, Bente; Bliddal, Henning; Graven-Nielsen, Thomas
2017-12-29
Background and aims Despite the high prevalence of knee osteoarthritis (OA) it remains one of the most frequent knee disorders without a cure. Pain and disability are prominent clinical features of knee OA. Knee OA pain is typically localized but can also be referred to the thigh or lower leg. Widespread hyperalgesia has been found in knee OA patients. In addition, patients with hyperalgesia in the OA knee joint show increased pain summation scores upon repetitive stimulation of the OA knee suggesting the involvement of facilitated central mechanisms in knee OA. The dynamics of the pain system (i.e., the adaptive responses to pain) has been widely studied, but mainly from experiments on healthy subjects, whereas less is known about the dynamics of the pain system in chronic pain patients, where the pain system has been activated for a long time. The aim of this study was to assess the dynamics of the nociceptive system quantitatively in knee osteoarthritis (OA) patients before and after induction of experimental knee pain. Methods Ten knee osteoarthritis (OA) patients participated in this randomized crossover trial. Each subject was tested on two days separated by 1 week. The most affected knee was exposed to experimental pain or control, in a randomized sequence, by injection of hypertonic saline into the infrapatellar fat pad and a control injection of isotonic saline. Pain areas were assessed by drawings on anatomical maps. Pressure pain thresholds (PPT) at the knee, thigh, lower leg, and arm were assessed before, during, and after the experimental pain and control conditions. Likewise, temporal summation of pressure pain on the knee, thigh and lower leg muscles was assessed. Results Experimental knee pain decreased the PPTs at the knee (P <0.01) and facilitated the temporal summation on the knee and adjacent muscles (P < 0.05). No significant difference was found at the control site (the contralateral arm) (P =0.77). Further, the experimental knee pain revealed
Ahn, Hyochol; Weaver, Michael; Lyon, Debra E; Kim, Junglyun; Choi, Eunyoung; Staud, Roland; Fillingim, Roger B
2017-02-01
Ethnicity has been associated with clinical and experimental pain responses. Whereas ethnic disparities in pain in other minority groups compared with whites are well described, pain in Asian Americans remains poorly understood. The purpose of this study was to characterize differences in clinical pain intensity and experimental pain sensitivity among older Asian American and non-Hispanic white (NHW) participants with knee osteoarthritis (OA). Data were collected from 50 Asian Americans ages 45 to 85 (28 Korean, 9 Chinese, 7 Japanese, 5 Filipino, and 1 Indian) and compared with 50 age-matched and sex-matched NHW individuals with symptomatic knee OA pain. The Western Ontario and McMaster Universities Osteoarthritis Index and Graded Chronic Pain Scale were used to assess the intensity of clinical knee pain. In addition, quantitative sensory testing was used to measure experimental sensitivity to heat-induced and mechanically induced pain. Asian American participants had significantly higher levels of clinical pain intensity than NHW participants with knee OA. In addition, Asian American participants had significantly higher experimental pain sensitivity than NHW participants with knee OA. These findings add to the growing literature regarding ethnic and racial differences in clinical pain intensity and experimental pain sensitivity. Asian Americans in particular may be at risk for clinical pain and heightened experimental pain sensitivity. Further investigation is needed to identify the mechanisms underlying ethnic group differences in pain between Asian Americans and NHWs, and to ensure that ethnic group disparities in pain are ameliorated.
Ahn, Hyochol; Weaver, Michael; Lyon, Debra; Kim, Junglyun; Choi, Eunyoung; Staud, Roland; Fillingim, Roger B.
2016-01-01
Objective Ethnicity has been associated with clinical and experimental pain responses. While ethnic disparities in pain in other minority groups compared to whites are well described, pain in Asian Americans remains poorly understood. The purpose of this study was to characterize differences in clinical pain intensity and experimental pain sensitivity among older Asian American and non-Hispanic White (NHW) participants with knee osteoarthritis (OA). Methods Data were collected from 50 Asian Americans ages 45-85 (28 Korean, 9 Chinese, 7 Japanese, 5 Filipino, and 1 Indian) and compared to 50 age- and gender-matched NHW individuals with symptomatic knee OA pain. The Western Ontario and McMaster Universities Osteoarthritis Index (WOMAC) and Graded Chronic Pain Scale (GCPS) were used to assess the intensity of clinical knee pain. In addition, quantitative sensory testing was used to measure experimental sensitivity to heat- and mechanically-induced pain. Results Asian American participants had significantly higher levels of clinical pain intensity than NHW participants with knee OA. In addition, Asian American participants had significantly higher experimental pain sensitivity than NHW participants with knee OA. Discussion These findings add to the growing literature regarding ethnic and racial differences in clinical pain intensity and experimental pain sensitivity. Asian Americans in particular may be at risk for clinical pain and heightened experimental pain sensitivity. Further investigation is needed to identify the mechanisms underlying ethnic group differences in pain between Asian Americans and non-Hispanic Whites, and to ensure that ethnic group disparities in pain are ameliorated. PMID:28060784
Herbert, Matthew S.; Goodin, Burel R.; Pero, Samuel T.; Schmidt, Jessica K.; Sotolongo, Adriana; Bulls, Hailey W.; Glover, Toni L.; King, Christopher D.; Sibille, Kimberly T.; Cruz-Almeida, Yenisel; Staud, Roland; Fessler, Barri J.; Bradley, Laurence A.; Fillingim, Roger B.
2014-01-01
Background Pain hypervigilance is an important aspect of the fear-avoidance model of pain that may help explain individual differences in pain sensitivity among persons with knee osteoarthritis (OA). Purpose The purpose of this study was to examine the contribution of pain hypervigilance to clinical pain severity and experimental pain sensitivity in persons with symptomatic knee OA. Methods We analyzed cross-sectional data from 168 adults with symptomatic knee OA. Quantitative sensory testing was used to measure sensitivity to heat pain, pressure pain, and cold pain, as well as temporal summation of heat pain, a marker of central sensitization. Results Pain hypervigilance was associated with greater clinical pain severity, as well as greater pressure pain. Pain hypervigilance was also a significant predictor of temporal summation of heat pain. Conclusions Pain hypervigilance may be an important contributor to pain reports and experimental pain sensitivity among persons with knee OA. PMID:24352850
Geber, Christian; Magerl, Walter; Fondel, Ricarda; Fechir, Marcel; Rolke, Roman; Vogt, Thomas; Treede, Rolf-Detlef; Birklein, Frank
2008-09-30
Pain patients often report distinct numbness of the painful skin although no structural peripheral or central nerve lesion is obvious. In this cross-sectional study we assessed the reduction of tactile function and studied underlying mechanisms in patients with chronic pain and in healthy participants exposed to phasic and tonic experimental nociceptive stimulation. Mechanical detection (MDT) and pain thresholds (MPT) were assessed in the painful area and the non-painful contralateral side in 10 patients with unilateral musculoskeletal pain. Additionally, 10 healthy participants were exposed to nociceptive stimulation applied to the volar forearms (capsaicin; electrical stimulation, twice each). Areas of tactile hypaesthesia and mechanical hyperalgesia were assessed. MDT and MPT were quantified adjacent to the stimulation site. Tactile hypaesthesia in pain patients and in experimental pain (MDT-z-scores: -0.66+/-0.30 and -0.42+/-0.15, respectively, both p<0.01) was paralleled by mechanical hyperalgesia (MPT-z-scores: +0.51+/-0.27, p<0.05; and +0.48+/-0.10, p<0.001). However, hypaesthesia and hyperalgesia were not correlated. Although 9 patients reported numbness, only 3 of them were able to delineate circumscript areas of tactile hypaesthesia. In experimental pain, the area of tactile hypaesthesia could be mapped in 31/40 experiments (78%). Irrespective of the mode of nociceptive stimulation (phasic vs. tonic) tactile hypaesthesia and hyperalgesia developed with a similar time course and disappeared within approximately 1 day. Hypaesthesia (numbness) often encountered in clinical pain can be reproduced by experimental nociceptive stimulation. The time course of effects suggests a mechanism involving central plasticity.
Hung, Ching-Hsia; Wang, Jeffrey Chi-Fei; Strichartz, Gary R
2015-09-01
Chronic pain after surgery limits social activity, interferes with work, and causes emotional suffering. A major component of such pain is reported as resting or spontaneous pain with no apparent external stimulus. Although experimental animal models can simulate the stimulus-evoked chronic pain that occurs after surgery, there have been no studies of spontaneous chronic pain in such models. Here the conditioned place preference (CPP) paradigm was used to reveal resting pain after experimental thoracotomy. Male Sprague Dawley rats received a thoracotomy with 1-hour rib retraction, resulting in evoked tactile hypersensitivity, previously shown to last for at least 9 weeks. Intraperitoneal injections of morphine (2.5 mg/kg) or gabapentin (40 mg/kg) gave equivalent 2- to 3-hour-long relief of tactile hypersensitivity when tested 12 to 14 days postoperatively. In separate experiments, single trial CPP was conducted 1 week before thoracotomy and then 12 days (gabapentin) or 14 days (morphine) after surgery, followed the next day by 1 conditioning session with morphine or gabapentin, both versus saline. The gabapentin-conditioned but not the morphine-conditioned rats showed a significant preference for the analgesia-paired chamber, despite the equivalent effect of the 2 agents in relieving tactile allodynia. These results show that experimental thoracotomy in rats causes spontaneous pain and that some analgesics, such as morphine, that reduce evoked pain do not also relieve resting pain, suggesting that pathophysiological mechanisms differ between these 2 aspects of long-term postoperative pain. Perspective: Spontaneous pain, a hallmark of chronic postoperative pain, is demonstrated here in a rat model of experimental postthoracotomy pain, further validating the use of this model for the development of analgesics to treat such symptoms. Although stimulus-evoked pain was sensitive to systemic morphine, spontaneous pain was not, suggesting different mechanistic
An experimental study of pain upon stimulation of the nasal and sinus cavities.
Clerico, Dean M
2014-01-01
To map different areas of pain sensitivity and to determine the existence and/or pattern of referred pain from upon stimulating the sinonasal cavity. Experimental human study. Mechanical and electrical stimulations to various anatomical structures and areas of the nasal and sinus cavities were conducted on nine volunteers. Intensity, location and character of pain were recorded in all subjects. The postero-superior (cephalic) aspect of the nasal cavity, primarily the anterior face of the sphenoid sinus and the superior turbinate, were the most sensitive sites, and the antero-inferior (caudal) region was the least sensitive. Referred pain to the head and face was reported by several subjects. Topographical differences in pain sensitivity exist in the sinonasal cavity. The phenomenon of referred pain from the nasal cavity was demonstrated. Copyright © 2014 Elsevier Inc. All rights reserved.
Nurses' response to pain communication from patients: a post-test experimental study.
McDonald, Deborah Dillon; Laporta, Matthew; Meadows-Oliver, Mikki
2007-01-01
Inadequate communication about pain can result in increased pain for patients. The purpose of the current pilot study was to test how nurses respond when patients use their own words, a pain intensity scale, or both to communicate pain. A post-test only experimental design was used with three pain description conditions, personal and numeric; personal only; numeric only. The setting included six hospitals and one school of nursing located in the northeastern United States. PARTICIPANTS included 122 registered medical surgical nurses. Nurses were randomly assigned to condition, and read a vignette about a trauma patient with moderately severe pain. The vignettes were identical except for the patient's pain description and age. The nurses then wrote how they would respond to the patient's pain. Two blind raters content analyzed the responses, giving nurses one point for including each of six a priori criteria derived from the Acute Pain Management Panel [1992. Acute Pain Management: operative or medical procedures and trauma. Clinical practice guideline (AHCPR Publication No. 92-0032)., Rockville, MD, USA] and the American Pain Society [2003. Principles of analgesic use in the treatment of acute pain and cancer pain, Glenville, IL, USA]. Nurses planned similar numbers of pain management strategies across the three conditions, with a mean of 2.1 (SD=1.14) strategies out of the recommended six. Nurses did not respond with more pain management strategies when patients describe pain in their own words, or in their own words and a pain intensity scale. The relatively small number of pain management strategies planned by the nurses suggests that nurses use few strategies to respond to moderately severe pain problems.
Pain referral and regional deep tissue hyperalgesia in experimental human hip pain models.
Izumi, Masashi; Petersen, Kristian Kjær; Arendt-Nielsen, Lars; Graven-Nielsen, Thomas
2014-04-01
Hip disorder patients typically present with extensive pain referral and hyperalgesia. To better understand underlying mechanisms, an experimental hip pain model was established in which pain referrals and hyperalgesia could be studied under standardized conditions. In 16 healthy subjects, pain was induced by hypertonic saline injection into the gluteus medius tendon (GMT), adductor longus tendon (ALT), or gluteus medius muscle (GMM). Isotonic saline was injected contralaterally as control. Pain intensity was assessed on a visual analogue scale (VAS), and subjects mapped the pain distribution. Before, during, and after injections, passive hip joint pain provocation tests were completed, together with quantitative sensory testing as follows: pressure pain thresholds (PPTs), cuff algometry pain thresholds (cuff PPTs), cutaneous pin-prick sensitivity, and thermal pain thresholds. Hypertonic saline injected into the GMT resulted in higher VAS scores than hypertonic injections into the ALT and GMM (P<.05). Referred pain areas spread to larger parts of the leg after GMT and GMM injections compared with more regionalized pain pattern after ALT injections (P<.05). PPTs at the injection site were decreased after hypertonic saline injections into GMT and GMM compared with baseline, ALT injections, and isotonic saline. Cuff PPTs from the thigh were decreased after hypertonic saline injections into the ALT compared with baseline, GMT injections, and isotonic saline (P<.05). More subjects had positive joint pain provocation tests after hypertonic compared with isotonic saline injections (P<.05), indicating that this provocation test also assessed hyperalgesia in extra-articular soft tissues. The experimental models may open for better understanding of pain mechanisms associated with painful hip disorders. Copyright © 2014 International Association for the Study of Pain. Published by Elsevier B.V. All rights reserved.
Experimental Sleep Restriction Facilitates Pain and Electrically Induced Cortical Responses
Matre, Dagfinn; Hu, Li; Viken, Leif A.; Hjelle, Ingri B.; Wigemyr, Monica; Knardahl, Stein; Sand, Trond; Nilsen, Kristian Bernhard
2015-01-01
Study Objectives: Sleep restriction (SR) has been hypothesized to sensitize the pain system. The current study determined whether experimental sleep restriction had an effect on experimentally induced pain and pain-elicited electroencephalographic (EEG) responses. Design: A paired crossover study. Intervention: Pain testing was performed after 2 nights of 50% SR and after 2 nights with habitual sleep (HS). Setting: Laboratory experiment at research center. Participants: Self-reported healthy volunteers (n = 21, age range: 18–31 y). Measurements and Results: Brief high-density electrical stimuli to the forearm skin produced pinprick-like pain. Subjective pain ratings increased after SR, but only in response to the highest stimulus intensity (P = 0.018). SR increased the magnitude of the pain-elicited EEG response analyzed in the time-frequency domain (P = 0.021). Habituation across blocks did not differ between HS and SR. Event-related desynchronization (ERD) was reduced after SR (P = 0.039). Pressure pain threshold of the trapezius muscle region also decreased after SR (P = 0.017). Conclusion: Sleep restriction (SR) increased the sensitivity to pressure pain and to electrically induced pain of moderate, but not low, intensity. The increased electrical pain could not be explained by a difference in habituation. Increased response magnitude is possibly related to reduced processing within the somatosensory cortex after partial SR. Citation: Matre D, Hu L, Viken LA, Hjelle IB, Wigemyr M, Knardahl S, Sand T, Nilsen KB. Experimental sleep restriction facilitates pain and electrically induced cortical responses. SLEEP 2015;38(10):1607–1617. PMID:26194577
The role of motivation in distracting attention away from pain: an experimental study.
Verhoeven, Katrien; Crombez, Geert; Eccleston, Christopher; Van Ryckeghem, Dimitri M L; Morley, Stephen; Van Damme, Stefaan
2010-05-01
Research on the effectiveness of distraction as a method of pain control is inconclusive. One mechanism pertains to the motivational relevance of distraction tasks. In this study the motivation to engage in a distraction task during pain was experimentally manipulated. Undergraduate students (N=73) participated in a cold pressor test (CPT) and were randomly assigned to three groups: a distraction-only group performed a tone-detection task during the CPT, a motivated-distraction group performed the same task and received a monetary reward for good task performance, and a control group did not perform the tone-detection task. Results indicated that engagement in the distraction task was better in the motivated-distraction group in comparison with the distraction-only group. Participants in both distraction groups experienced less pain compared to the control group. There were no overall differences in pain intensity between the two distraction groups. The effect of distraction was influenced by the level of catastrophic thinking about pain. For low catastrophizers, both distraction groups reported less pain as compared to the non-distracted control group. This was not the case for high catastrophizers. For high catastrophizers it mattered whether the distraction task was motivationally relevant: high catastrophizers reported less intense pain in the motivated-distraction group, as compared to the non-distracted control group. We conclude that increasing the motivational relevance of the distraction task may increase the effects of distraction, especially for those who catastrophize about pain. Copyright 2010 International Association for the Study of Pain. Published by Elsevier B.V. All rights reserved.
Racial and ethnic differences in experimental pain sensitivity: systematic review and meta-analysis.
Kim, Hee Jun; Yang, Gee Su; Greenspan, Joel D; Downton, Katherine D; Griffith, Kathleen A; Renn, Cynthia L; Johantgen, Meg; Dorsey, Susan G
2017-02-01
Our objective was to describe the racial and ethnic differences in experimental pain sensitivity. Four databases (PubMed, EMBASE, the Cochrane Central Register of Controlled Trials, and PsycINFO) were searched for studies examining racial/ethnic differences in experimental pain sensitivity. Thermal-heat, cold-pressor, pressure, ischemic, mechanical cutaneous, electrical, and chemical experimental pain modalities were assessed. Risk of bias was assessed using the Agency for Healthcare Research and Quality guideline. Meta-analysis was used to calculate standardized mean differences (SMDs) by pain sensitivity measures. Studies comparing African Americans (AAs) and non-Hispanic whites (NHWs) were included for meta-analyses because of high heterogeneity in other racial/ethnic group comparisons. Statistical heterogeneity was assessed by subgroup analyses by sex, sample size, sample characteristics, and pain modalities. A total of 41 studies met the review criteria. Overall, AAs, Asians, and Hispanics had higher pain sensitivity compared with NHWs, particularly lower pain tolerance, higher pain ratings, and greater temporal summation of pain. Meta-analyses revealed that AAs had lower pain tolerance (SMD: -0.90, 95% confidence intervals [CIs]: -1.10 to -0.70) and higher pain ratings (SMD: 0.50, 95% CI: 0.30-0.69) but no significant differences in pain threshold (SMD: -0.06, 95% CI: -0.23 to 0.10) compared with NHWs. Estimates did not vary by pain modalities, nor by other demographic factors; however, SMDs were significantly different based on the sample size. Racial/ethnic differences in experimental pain sensitivity were more pronounced with suprathreshold than with threshold stimuli, which is important in clinical pain treatment. Additional studies examining mechanisms to explain such differences in pain tolerance and pain ratings are needed.
Experimental Sleep Restriction Facilitates Pain and Electrically Induced Cortical Responses.
Matre, Dagfinn; Hu, Li; Viken, Leif A; Hjelle, Ingri B; Wigemyr, Monica; Knardahl, Stein; Sand, Trond; Nilsen, Kristian Bernhard
2015-10-01
Sleep restriction (SR) has been hypothesized to sensitize the pain system. The current study determined whether experimental sleep restriction had an effect on experimentally induced pain and pain-elicited electroencephalographic (EEG) responses. A paired crossover study. Pain testing was performed after 2 nights of 50% SR and after 2 nights with habitual sleep (HS). Laboratory experiment at research center. Self-reported healthy volunteers (n = 21, age range: 18-31 y). Brief high-density electrical stimuli to the forearm skin produced pinprick-like pain. Subjective pain ratings increased after SR, but only in response to the highest stimulus intensity (P = 0.018). SR increased the magnitude of the pain-elicited EEG response analyzed in the time-frequency domain (P = 0.021). Habituation across blocks did not differ between HS and SR. Event-related desynchronization (ERD) was reduced after SR (P = 0.039). Pressure pain threshold of the trapezius muscle region also decreased after SR (P = 0.017). Sleep restriction (SR) increased the sensitivity to pressure pain and to electrically induced pain of moderate, but not low, intensity. The increased electrical pain could not be explained by a difference in habituation. Increased response magnitude is possibly related to reduced processing within the somatosensory cortex after partial SR. © 2015 Associated Professional Sleep Societies, LLC.
Riddle, Daniel L.; Keefe, Francis J.; Nay, William T.; McKee, Daphne; Attarian, David E.; Jensen, Mark P.
2011-01-01
Objectives To (1) describe a behavioral intervention designed for patients with elevated pain catastrophizing who are scheduled for knee arthroplasty, and (2) use a quasi-experimental design to evaluate the potential efficacy of the intervention on pain severity, catastrophizing cognitions, and disability. Design Quasi-experimental non-equivalent control group design with a 2 month follow-up. Setting Two university-based Orthopedic Surgery departments. Participants Adults scheduled for knee replacement surgery who reported elevated levels of pain catastrophizing. Patients were recruited from two clinics and were assessed prior to surgery and 2 months following surgery. Intervention A group of 18 patients received a psychologist directed pain coping skills training intervention comprising 8 sessions and the other group, a historical cohort of 45 patients, received usual care. Main Outcome Measures WOMAC Pain and Disability scores as well as scores on the Pain Catastrophizing Scale. Results Two months following surgery, the patients who received pain coping skills training reported significantly greater reductions in pain severity and catastrophizing, and greater improvements in function as compared to the usual care cohort. Conclusion Pain catastrophizing is known to increase risk of poor outcome following knee arthroplasty. The findings provide preliminary evidence that the treatment may be highly efficacious for reducing pain, catastrophizing, and disability, in patients reporting elevated catastrophizing prior to knee arthroplasty. A randomized clinical trial is warranted to confirm these effects. PMID:21530943
Periodontal CGRP contributes to orofacial pain following experimental tooth movement in rats.
Long, Hu; Liao, Lina; Gao, Meiya; Ma, Wenqiang; Zhou, Yang; Jian, Fan; Wang, Yan; Lai, Wenli
2015-08-01
Calcitonin-related gene peptide (CGRP) plays an important role in orofacial inflammatory pain. The aim of this study was to determine whether periodontal CGRP contributes to orofacial pain induced by experimental tooth movement in rats. Male Sprague-Dawley rats were used in this study. Closed coil springs were used to deliver forces. Rats were euthanized on 0d, 1d, 3d, 5d, 7d, and 14d following experimental tooth movement. Then, alveolar bones were obtained for immunostaining of periodontal tissues against CGRP. Two hours prior to euthanasia on each day, orofacial pain levels were assessed through rat grimace scale. CGRP and olcegepant (CGRP receptor antagonist) were injected into periodontal tissues to verify the roles of periodontal CGRP in orofacial pain induced by experimental tooth movement. Periodontal CGRP expression levels and orofacial pain levels were elevated on 1d, 3d, 5d, and 7d following experimental tooth movement. The two indices were significantly correlated with each other and fitted into a dose-response model. Periodontal administration of CGRP could elevate periodontal CGRP expressions and exacerbate orofacial pain. Moreover, olcegepant administration could decrease periodontal CGRP expressions and alleviate orofacial pain. Therefore, periodontal CGRP plays an important role in pain transmission and modulation following experimental tooth movement. We suggest that it may participate in a positive feedback aiming to amplify orofacial pain signals. Copyright © 2015 Elsevier B.V. All rights reserved.
Beaulieu, Karen; Beland, Patricia; Pinard, Marilee; Handfield, Guilène; Handfield, Nicole; Goffaux, Philippe; Corriveau, Hélène; Léonard, Guillaume
2016-01-01
Previous studies suggested that pulsed electromagnetic field (PEMF) therapy can decrease pain. To date, however, it remains difficult to determine whether the analgesic effect observed in patients are attributable to a direct effect of PEMF on pain or to an indirect effect of PEMF on inflammation and healing. In the present study, we used an experimental pain paradigm to evaluate the direct effect of PEMF on pain intensity, pain unpleasantness, and temporal summation of pain. Twenty-four healthy subjects (mean age 22 ± 2 years; 9 males) participated in the experiment. Both real and sham PEMF were administered to every participant using a randomized, double-blind, cross-over design. For each visit, PEMF was applied for 10 minutes on the right forearm using a portable device. Experimental pain was evoked before (baseline) and after PEMF with a 9 cm(2) Pelletier-type thermode, applied on the right forearm (120 s stimulation; temperature individually adjusted to produce moderate baseline pain). Pain intensity and unpleasantness were evaluated using a 0-100 numerical pain rating scale. Temporal summation was evaluated by comparing pain intensity ratings obtained at the end of tonic nociceptive stimulation (120 s) with pain intensity ratings obtained after 60 s of stimulation. When compared to baseline, there was no change in pain intensity and unpleasantness following the application of real or sham PEMF. PEMF did not affect temporal summation. The present observations suggest that PEMF does not directly influence heat pain perception in healthy individuals.
Meints, Samantha M; Stout, Madison; Abplanalp, Samuel; Hirsh, Adam T
2017-03-01
Compared with white individuals and men, black individuals and women show a lower tolerance for experimental pain stimuli. Previous studies suggest that pain catastrophizing is important in this context, but little is known about which components of catastrophizing contribute to these race and sex differences. The purpose of the current study was to examine the individual components of catastrophizing (rumination, magnification, and helplessness) as candidate mediators of race and sex differences in experimental pain tolerance. Healthy undergraduates (N = 172, 74% female, 43.2% black) participated in a cold pressor task and completed a situation-specific version of the Pain Catastrophizing Scale. Black and female participants showed a lower pain tolerance than white (P < .01, d = .70) and male (P < .01, d = .55) participants, respectively. Multiple mediation analyses indicated that these race and sex differences were mediated by the rumination component of catastrophizing (indirect effect = -7.13, 95% confidence interval (CI), -16.20 to -1.96, and 5.75, 95% CI, .81-15.57, respectively) but not by the magnification (95% CI, -2.91 to 3.65 and -1.54 to 1.85, respectively) or helplessness (95% CI, -5.53 to 3.31 and -.72 to 5.38, respectively) components. This study provides new information about race and sex differences in pain and suggests that treatments targeting the rumination component of catastrophizing may help mitigate pain-related disparities. This study suggests that differences in pain-related rumination, but not magnification or helplessness, are important contributors to race and sex differences in the pain experience. Interventions that target this maladaptive cognitive style may help reduce disparities in pain. Copyright © 2016 American Pain Society. Published by Elsevier Inc. All rights reserved.
Wong, Arnold Y L; Parent, Eric C; Prasad, Narasimha; Huang, Christopher; Chan, K Ming; Kawchuk, Gregory N
2016-05-01
While some patients with low back pain demonstrate increased spinal stiffness that decreases as pain subsides, this observation is inconsistent. Currently, the relation between spinal stiffness and low back pain remains unclear. This study aimed to investigate the effects of experimental low back pain on temporal changes in posteroanterior spinal stiffness and concurrent trunk muscle activity. In separate sessions five days apart, nine asymptomatic participants received equal volume injections of hypertonic or isotonic saline in random order into the L3-L5 interspinous ligaments. Pain intensity, spinal stiffness (global and terminal stiffness) at the L3 level, and the surface electromyographic activity of six trunk muscles were measured before, immediately after, and 25-minute after injections. These outcome measures under different saline conditions were compared by generalized estimating equations. Compared to isotonic saline injections, hypertonic saline injections evoked significantly higher pain intensity (mean difference: 5.7/10), higher global (mean difference: 0.73N/mm) and terminal stiffness (mean difference: 0.58N/mm), and increased activity of four trunk muscles during indentation (P<0.05). Both spinal stiffness and trunk muscle activity returned to baseline levels as pain subsided. While previous clinical research reported inconsistent findings regarding the association between spinal stiffness and low back pain, our study revealed that experimental pain caused temporary increases in spinal stiffness and concurrent trunk muscle co-contraction during indentation, which helps explain the temporal relation between spinal stiffness and low back pain observed in some clinical studies. Our results substantiate the role of spinal stiffness assessments in monitoring back pain progression. Copyright © 2016 Elsevier Ltd. All rights reserved.
Controlled dilatation of the uterine cervix--an experimental visceral pain model.
Bajaj, Priti; Drewes, Asbjørn M; Gregersen, Hans; Petersen, Poul; Madsen, Hans; Arendt-Nielsen, Lars
2002-10-01
Pain originating from the female reproductive organs is a substantial clinical problem to treat. Experimental models may be a tool for the study of visceral pain mechanisms and hence provide information to aid in formulating new treatment strategies. The aim was to develop and evaluate the performance and safety of a model for nociceptive stimulation of the uterine cervix by balloon dilatation using impedance planimetry. Three consecutive (repeated) dilatations at 1 ml/min, an isovolumetric and a fast dilatation at 2 ml/min were performed. Pilot studies were conducted in vitro on hysterectomy specimens, followed by application of the model in 14 healthy females. Subjects indicated the quality of perception and pain during dilatations by verbal reports and the McGill Pain Questionnaire (MPQ), and the intensity by a continuous electronic visual analog scale. The pain location was marked on an anatomical map. The balloon cross-sectional area (CSA) was measured simultaneously. The experimental procedure was atraumatic. Pain was evoked in all subjects, with referral to the hypogastric and low back regions. The word descriptors on the MPQ and the areas of referred sensations were similar to that seen clinically in abortion, labor and menstrual pain. The pain intensity correlated with balloon CSA (r=0.9, P<0.001). No significant differences were found for the balloon volumes (4.2, 3.8 and 3.9 ml) or CSA (163, 122 and 123 mm(2)) to pain threshold (PT) for repeated dilatations, suggesting the reliability of the model. There was significant correlation between the balloon volume and CSA to reach the PT for single and repeated cervical dilatations. During isovolumetric distension, greater overall pain intensity was demonstrated for the prolonged as compared to the shorter duration cervical stimulation. In conclusion, this is the first human experimental pain model for dilatation of the uterine cervix, providing a safe, controlled, quantifiable stimulus that evoked reliable
Experimental neck muscle pain impairs standing balance in humans.
Vuillerme, Nicolas; Pinsault, Nicolas
2009-02-01
Impaired postural control has been reported in patients with chronic neck pain of both traumatic and non-traumatic etiologies, but whether painful stimulation of neck muscle per se can affect balance control during quiet standing in humans remains unclear. The purpose of the present experiment was thus to investigate the effect of experimental neck muscle pain on standing balance in young healthy adults. To achieve this goal, 16 male university students were asked to stand upright as still as possible on a force platform with their eyes closed in two conditions of No pain and Pain of the neck muscles elicited by experimental painful electrical stimulation. Postural control and postural performance were assessed by the displacements of the center of foot pressure (CoP) and of the center of mass (CoM), respectively. The results showed increased CoP and CoM displacements variance, range, mean velocity, and mean and median frequencies in the Pain relative to the No pain condition. The present findings emphasize the destabilizing effect of experimental neck muscle pain per se, and more largely stress the importance of intact neck neuromuscular function on standing balance.
Schinkel, Meghan G; Chambers, Christine T; Corkum, Penny; Jacques, Sophie
2018-04-16
Research on family factors in paediatric pain has primarily focused on parents; the role of siblings has been largely ignored. This study examined whether sibling relationship quality was related to siblings' behaviours during experimental pain, and whether the behaviours of an observing sibling were related to children's pain outcomes. Ninety-two sibling dyads between 8-12 years old completed both observational and questionnaire measures of sibling relationship quality. Children took turns completing the cold pressor task (CPT) in a counterbalanced order with their sibling present. Pain outcomes (intensity, fear, tolerance) were recorded for each sibling, and the behaviour of the observing and participating siblings during the CPT were coded as attending, non-attending, and coping/encouragement. Structural equation modelling, using the actor-partner interdependence model, was conducted to analyse the dyadic data. While participating in the CPT with their sibling present, greater levels of warmth and positivity in the sibling relationship were related to children engaging in more non-attending behaviours and less attending behaviours. Greater levels of attending behaviours by the observing child was related to the sibling having a lower pain tolerance, and greater levels of coping/encouragement behaviours by the observing child was related to the sibling reporting greater pain intensity and fear during the CPT. Children with warmer/positive sibling relationships were more likely to respond to acute pain by shifting the focus away from their pain experience (e.g., through distraction) when a sibling was present. Pain-focused behaviours by an observing sibling are related to greater child pain and fear during experimental pain.
Nonpainful wide-area compression inhibits experimental pain
Honigman, Liat; Bar-Bachar, Ofrit; Yarnitsky, David; Sprecher, Elliot; Granovsky, Yelena
2016-01-01
Abstract Compression therapy, a well-recognized treatment for lymphoedema and venous disorders, pressurizes limbs and generates massive non-noxious afferent sensory barrages. The aim of this study was to study whether such afferent activity has an analgesic effect when applied on the lower limbs, hypothesizing that larger compression areas will induce stronger analgesic effects, and whether this effect correlates with conditioned pain modulation (CPM). Thirty young healthy subjects received painful heat and pressure stimuli (47°C for 30 seconds, forearm; 300 kPa for 15 seconds, wrist) before and during 3 compression protocols of either SMALL (up to ankles), MEDIUM (up to knees), or LARGE (up to hips) compression areas. Conditioned pain modulation (heat pain conditioned by noxious cold water) was tested before and after each compression protocol. The LARGE protocol induced more analgesia for heat than the SMALL protocol (P < 0.001). The analgesic effect interacted with gender (P = 0.015). The LARGE protocol was more efficient for females, whereas the MEDIUM protocol was more efficient for males. Pressure pain was reduced by all protocols (P < 0.001) with no differences between protocols and no gender effect. Conditioned pain modulation was more efficient than the compression-induced analgesia. For the LARGE protocol, precompression CPM efficiency positively correlated with compression-induced analgesia. Large body area compression exerts an area-dependent analgesic effect on experimental pain stimuli. The observed correlation with pain inhibition in response to robust non-noxious sensory stimulation may suggest that compression therapy shares similar mechanisms with inhibitory pain modulation assessed through CPM. PMID:27152691
Nonpainful wide-area compression inhibits experimental pain.
Honigman, Liat; Bar-Bachar, Ofrit; Yarnitsky, David; Sprecher, Elliot; Granovsky, Yelena
2016-09-01
Compression therapy, a well-recognized treatment for lymphoedema and venous disorders, pressurizes limbs and generates massive non-noxious afferent sensory barrages. The aim of this study was to study whether such afferent activity has an analgesic effect when applied on the lower limbs, hypothesizing that larger compression areas will induce stronger analgesic effects, and whether this effect correlates with conditioned pain modulation (CPM). Thirty young healthy subjects received painful heat and pressure stimuli (47°C for 30 seconds, forearm; 300 kPa for 15 seconds, wrist) before and during 3 compression protocols of either SMALL (up to ankles), MEDIUM (up to knees), or LARGE (up to hips) compression areas. Conditioned pain modulation (heat pain conditioned by noxious cold water) was tested before and after each compression protocol. The LARGE protocol induced more analgesia for heat than the SMALL protocol (P < 0.001). The analgesic effect interacted with gender (P = 0.015). The LARGE protocol was more efficient for females, whereas the MEDIUM protocol was more efficient for males. Pressure pain was reduced by all protocols (P < 0.001) with no differences between protocols and no gender effect. Conditioned pain modulation was more efficient than the compression-induced analgesia. For the LARGE protocol, precompression CPM efficiency positively correlated with compression-induced analgesia. Large body area compression exerts an area-dependent analgesic effect on experimental pain stimuli. The observed correlation with pain inhibition in response to robust non-noxious sensory stimulation may suggest that compression therapy shares similar mechanisms with inhibitory pain modulation assessed through CPM.
Role of gender norms and group identification on hypothetical and experimental pain tolerance.
Pool, Gregory J; Schwegler, Andria F; Theodore, Brian R; Fuchs, Perry N
2007-05-01
Previous research indicates that men typically tolerate more pain in experimental settings than women. One likely explanation for these group differences in pain tolerance is conformity to traditional, gender group social norms (i.e., the ideal man is masculine and tolerates more pain; the ideal woman is feminine and tolerates less pain). According to self-categorization theory, norms guide behavior to the degree that group members adopt the group identity. Therefore, high-identifying men are expected to conform to gender norms and tolerate more pain than high-identifying women who conform to different gender norms as a guide for their behavior. We conducted two studies to investigate whether gender group identification moderates individuals' conformity to pain tolerance and reporting norms. In the first study, participants indicated their gender identification and expected tolerance of a hypothetical painful stimulus. As anticipated, high-identifying men reported significantly greater pain tolerance than high-identifying women. No differences existed between low-identifying men and women. To determine if self-reported pain tolerance in a role-playing scenario corresponds to actual pain tolerance in an experimental setting, the second study examined pain tolerance to a noxious stimulus induced by electrical stimulation of the index finger. The experimental outcome revealed that high-identifying men tolerated more painful stimulation than high-identifying women. Further, high-identifying men tolerated more pain than low-identifying men. These results highlight the influence of social norms on behavior and suggest the need to further explore the role of norms in pain reporting behaviors.
Drew, M K; Palsson, T S; Hirata, R P; Izumi, M; Lovell, G; Welvaert, M; Chiarelli, P; Osmotherly, P G; Graven-Nielsen, T
2017-10-01
To investigate the effects of experimental adductor pain on the pain referral pattern, mechanical sensitivity and muscle activity during common clinical tests. Repeated-measures design. In two separate sessions, 15 healthy males received a hypertonic (painful) and isotonic (control) saline injection to either the adductor longus (AL) tendon to produce experimental groin pain or into the rectus femoris (RF) tendon as a painful control. Pain intensity was recorded on a visual analogue scale (VAS) with pain distribution indicated on body maps. Pressure pain thresholds (PPT) were assessed bilaterally in the groin area. Electromyography (EMG) of relevant muscles was recorded during six provocation tests. PPT and EMG assessment were measured before, during and after experimental pain. Hypertonic saline induced higher VAS scores than isotonic saline (p<0.001), and a local pain distribution in 80% of participants. A proximal pain referral to the lower abdominal region in 33% (AL) and 7% (RF) of participants. Experimental pain (AL and RF) did not significantly alter PPT values or the EMG amplitude in groin or trunk muscles during provocation tests when forces were matched with baseline. This study demonstrates that AL tendon pain was distributed locally in the majority of participants but may refer to the lower abdomen. Experimental adductor pain did not significantly alter the mechanical sensitivity or muscle activity patterns. Copyright © 2017 Sports Medicine Australia. Published by Elsevier Ltd. All rights reserved.
İşlekdemir, Burcu; Kaya, Nurten
2016-01-01
Patients generally prefer to have their family present during medical or nursing interventions. Family presence is assumed to reduce anxiety, especially during painful interventions. This study employed a randomized controlled experimental design to determine the effects of family presence on pain and anxiety during invasive nursing procedures. The study population consisted of patients hospitalized in the observation unit of the internal medicine section in the emergency department of a university hospital. The sample comprised 138 patients assigned into the experimental and control groups by drawing lots. The invasive nursing procedure was carried out in the presence of family members, for members of the experimental group, and without family members, for members of the control group. Thus, the effects of family presence on pain and anxiety during the administration of an invasive nursing procedure to patients were analyzed. The results showed that members of the experimental and control groups did not differ with respect to the pain and state anxiety scores during the intervention. Family presence does not influence the participants' pain and anxiety during an invasive nursing procedure. Thus, the decision regarding family presence during such procedures should be based on patient preference. Copyright © 2015 Elsevier Ltd. All rights reserved.
Gender role affects experimental pain responses: a systematic review with meta-analysis.
Alabas, O A; Tashani, O A; Tabasam, G; Johnson, M I
2012-10-01
Gender role refers to the culturally and socially constructed meanings that describe how women and men should behave in certain situations according to feminine and masculine roles learned throughout life. The aim of this meta-analysis was to evaluate the relationship between gender role and experimental pain responses in healthy human participants. We searched computerized databases for studies published between January 1950 and May 2011 that had measured gender role in healthy human adults and pain response to noxious stimuli. Studies were entered into a meta-analysis if they calculated a correlation coefficient (r) for gender role and experimental pain. Searches yielded 4465 'hits' and 13 studies were eligible for review. Sample sizes were 67-235 participants and the proportion of female participants was 45-67%. Eight types of gender role instrument were used. Meta-analysis of six studies (406 men and 539 women) found a significant positive correlation between masculine and feminine personality traits and pain threshold and tolerance, with a small effect size (r = 0.17, p = 0.01). Meta-analysis of four studies (263 men and 297 women) found a significant negative correlation between gender stereotypes specific to pain and pain threshold and tolerance, with a moderate effect size (r = -0.41, p < 0.001). In conclusion, individuals who considered themselves more masculine and less sensitive to pain than the typical man showed higher pain thresholds and tolerances. Gender stereotypes specific to pain scales showed stronger associations with sex differences in pain sensitivity response than masculine and feminine personality trait scales. © 2012 European Federation of International Association for the Study of Pain Chapters.
Effects of intrathecal ketorolac on human experimental pain
Eisenach, James C.; Curry, Regina; Tong, Chuanyao; Houle, Timothy T.; Yaksh, Tony L.
2010-01-01
Background Nonsteroidal antiinflammatory drugs, the most commonly used analgesics, reduce pain by inhibiting cyclooxygenase at peripheral sites of inflammation, but potentially also by inhibiting cyclooxygenase in the central nervous system, especially the spinal cord. Animal studies suggest that products of cyclooxygenase in the spinal cord do not alter pain responses to acute noxious stimuli, but reduce pain and sensitization following peripheral inflammation. We used spinal injection of small doses of the cyclooxygenase inhibitor, ketorolac, to survey the role of spinal cyclooxygenase in human experimental pain and hypersensitivity states. Methods Following regulatory agency approval and informed consent, we examined the effect of 2.0 mg intrathecal ketorolac in 41 healthy volunteers to acute noxious thermal stimuli in normal skin and to mechanical stimuli in skin sensitized by topical capsaicin or ultraviolet burn. We also examined the effect of intravenous ketorolac, Results Intrathecal ketorolac reduced hypersensitivity when it was induced by a combination of ultraviolet burn plus intermittent heat and, according to one of two analytical strategies, when it was induced by ultraviolet burn alone. Conclusions These data suggest a more limited role for spinal cord cyclooxygenase in human pain states than predicted by studies in animals. PMID:20395821
Sex, Gender, and Pain: A Review of Recent Clinical and Experimental Findings
Fillingim, Roger B.; King, Christopher D.; Ribeiro-Dasilva, Margarete C.; Rahim-Williams, Bridgett; Riley, Joseph L.
2009-01-01
Sex-related influences on pain and analgesia have become a topic of tremendous scientific and clinical interest, especially in the last 10 to 15 years. Members of our research group published reviews of this literature more than a decade ago, and the intervening time period has witnessed robust growth in research regarding sex, gender, and pain. Therefore, it seems timely to revisit this literature. Abundant evidence from recent epidemiologic studies clearly demonstrates that women are at substantially greater risk for many clinical pain conditions, and there is some suggestion that postoperative and procedural pain may be more severe among women than men. Consistent with our previous reviews, current human findings regarding sex differences in experimental pain indicate greater pain sensitivity among females compared with males for most pain modalities, including more recently implemented clinically relevant pain models such as temporal summation of pain and intramuscular injection of algesic substances. The evidence regarding sex differences in laboratory measures of endogenous pain modulation is mixed, as are findings from studies using functional brain imaging to ascertain sex differences in pain-related cerebral activation. Also inconsistent are findings regarding sex differences in responses to pharmacologic and non-pharmacologic pain treatments. The article concludes with a discussion of potential biopsychosocial mechanisms that may underlie sex differences in pain, and considerations for future research are discussed. Perspective This article reviews the recent literature regarding sex, gender, and pain. The growing body of evidence that has accumulated in the past 10 to 15 years continues to indicate substantial sex differences in clinical and experimental pain responses, and some evidence suggests that pain treatment responses may differ for women versus men. PMID:19411059
Vuilleumier, Pascal H; Besson, Marie; Desmeules, Jules; Arendt-Nielsen, Lars; Curatolo, Michele
2013-01-01
Compounds that act on GABA-receptors produce anti-hyperalgesia in animal models, but little is known on their effects in humans. The aim of this study was to explore the potential usefulness of GABA-agonism for the control of pain in humans. Two agonists at the benzodiazepine-binding site of GABAA-receptors (clobazam and clonazepam) were studied using multiple experimental pain tests. Positive results would support further investigation of GABA agonism for the control of clinical pain. In a randomized double-blind crossover design, 16 healthy male volunteers received clobazam 20 mg, clonazepam 1 mg and tolterodine 1 mg (active placebo). The area of static hyperalgesia after intradermal capsaicin injection was the primary endpoint. Secondary endpoints were: area of dynamic hyperalgesia, response to von Frey hair stimulation, pressure pain thresholds, conditioned pain modulation, cutaneous and intramuscular electrical pain thresholds (1, 5 and 20 repeated stimulation), and pain during cuff algometry. For the primary endpoint, an increase in the area of static hyperalgesia was observed after administration of placebo (p<0.001), but not after clobazam and clonazepam. Results suggestive for an anti-hyperalgesic effect of the benzodiazepines were obtained with all three intramuscular pain models and with cuff algometry. No effect could be detected with the other pain models employed. Collectively, the results are suggestive for a possible anti-hyperalgesic effect of drugs acting at the GABAA-receptors in humans, particularly in models of secondary hyperalgesia and deep pain. The findings are not conclusive, but support further clinical research on pain modulation by GABAergic drugs. Because of the partial results, future research should focus on compounds acting selectively on subunits of the GABA complex, which may allow the achievement of higher receptor occupancy than unselective drugs. Our data also provide information on the most suitable experimental models for
Length of perineal pain relief after ice pack application: A quasi-experimental study.
de Souza Bosco Paiva, Caroline; Junqueira Vasconcellos de Oliveira, Sonia Maria; Amorim Francisco, Adriana; da Silva, Renata Luana; de Paula Batista Mendes, Edilaine; Steen, Mary
2016-04-01
Ice pack is effective for alleviating postpartum perineal pain in primiparous women while multiparous women's levels of perineal pain appear to be poorly explored. Ice pack is a low-cost non-invasive localised treatment that can be used with no impact on breastfeeding. However, how long perineal analgesia persists after applying an ice pack is still unknown. To evaluate if perineal analgesia is maintained up to 2h after applying an ice pack to the perineum for 20min. A quasi-experimental study, using a pre and post-test design, was undertaken with a sample size of 50 multiparous women in Brazil. Data was collected by structured interview. The intervention involved a single application of an ice pack applied for 20min to the perineal area of women who reported perineal pain ≥3 by use of a numeric rating scale (0-10), with intact perineum, 1st or 2nd degree lacerations or episiotomy, between 6 and 24h after spontaneous vaginal birth. Perineal pain was evaluated at three points of time: before, immediately after and 2h after applying an ice pack. Immediately after applying an ice pack to the perineal area, there was a significant reduction in the severity of perineal pain reported (5.4 vs. 1.0, p<0.0005), which continued for 1h 35min up to 2h after the local application. Ice pack application for 20min is effective for alleviating postpartum perineal pain and continues to be effective between 1h 35min for up to 2h. Copyright © 2015 Australian College of Midwives. Published by Elsevier Ltd. All rights reserved.
Pain perception in people with Down syndrome: a synthesis of clinical and experimental research
McGuire, Brian E.; Defrin, Ruth
2015-01-01
People with an intellectual disability experience both acute and chronic pain with at least the same frequency as the general population. However, considerably less is known about the pain perception of people with Down syndrome. In this review paper, we evaluated the available clinical and experimental evidence. Some experimental studies of acute pain have indicated that pain threshold was higher than normal but only when using a reaction time method to measure pain sensitivity. However, when reaction time is not part of the calculation of the pain threshold, pain sensitivity in people with Down syndrome is in fact lower than normal (more sensitive to pain). Clinical studies of chronic pain have shown that people with an intellectual disability experience chronic pain and within that population, people with Down syndrome also experience chronic pain, but the precise prevalence of chronic pain in Down syndrome has yet to be established. Taken together, the literature suggests that people with Down syndrome experience pain, both acute and chronic, with at least the same frequency as the rest of the population. Furthermore, the evidence suggests that although acute pain expression appears to be delayed, once pain is registered, there appears to be a magnified pain response. We conclude by proposing an agenda for future research in this area. PMID:26283936
Rahim-Williams, Bridgett; Riley, Joseph L; Williams, Ameenah K K; Fillingim, Roger B
2012-04-01
Pain is a subjectively complex and universal experience. We examine research investigating ethnic group differences in experimental pain response and factors contributing to group differences. We conducted a systematic literature review and analysis of studies using experimental pain stimuli to assess pain sensitivity across multiple ethnic groups. Our search covered the period from 1944 to 2011, and used the PubMed bibliographic database; a reference source containing over 17 million citations. We calculated effect sizes; identified ethnic/racial group categories, pain stimuli, and measures; and examined findings regarding biopsychosociocultural factors contributing to ethnic/racial group differences. We found 472 studies investigating ethnic group differences and pain. Twenty-six of these met our review inclusion criteria of investigating ethnic group differences in experimental pain. The majority of studies included comparisons between African Americans (AA) and non-Hispanic Whites (NHW). There were consistently moderate to large effect sizes for pain tolerance across multiple stimulus modalities; AA demonstrated lower pain tolerance. For pain threshold, findings were generally in the same direction, but effect sizes were small to moderate across ethnic groups. Limited data were available for suprathreshold pain ratings. A subset of studies comparing NHW and other ethnic groups showed a variable range of effect sizes for pain threshold and tolerance. There are potentially important ethnic/racial group differences in experimental pain perception. Elucidating ethnic group differences has translational merit for culturally competent clinical care and for addressing and reducing pain treatment disparities among ethnically/racially diverse groups. Wiley Periodicals, Inc.
Riley, Joseph L.; Williams, Ameenah K.K.; Fillingim, Roger B.
2012-01-01
Objective Pain is a subjectively complex and universal experience. We examine research investigating ethnic group differences in experimental pain response, and factors contributing to group differences. Method We conducted a systematic literature review and analysis of studies using experimental pain stimuli to assess pain sensitivity across multiple ethnic groups. Our search covered the period from 1944-2011, and utilized the PUBMED bibliographic database; a reference source containing over 17 million citations. We calculated effect sizes, identified ethnic/racial group categories, pain stimuli and measures, and examined findings regarding biopsychosociocultural factors contributing to ethnic/racial group differences. Results We found 472 studies investigating ethnic group differences and pain. Twenty-six of these met our review inclusion criteria of investigating ethnic group differences in experimental pain. The majority of studies included comparisons between African Americans (AA) and non-Hispanic Whites (NHW). There were consistently moderate to large effect sizes for pain tolerance across multiple stimulus modalities; African Americans demonstrated lower pain tolerance. For pain threshold, findings were generally in the same direction, but effect sizes were small to moderate across ethnic groups. Limited data were available for suprathreshold pain ratings. A subset of studies comparing NHW and other ethnic groups showed a variable range of effect sizes for pain threshold and tolerance. Conclusion There are potentially important ethnic/racial group differences in experimental pain perception. Elucidating ethnic group differences, has translational merit for culturally-competent clinical care and for addressing and reducing pain treatment disparities among ethnically/racially diverse groups. PMID:22390201
Vitamin D, Race, and Experimental Pain Sensitivity in Older Adults with Knee Osteoarthritis
Glover, T.L.; Goodin, B.R.; Horgas, A.L.; Kindler, L.L.; King, C.D.; Sibille, K.T.; Peloquin, C.A.; Riley, J.L.; Staud, R.; Bradley, L.A.; Fillingim, R.B.
2012-01-01
Objective Low levels of serum circulating 25-hydroxyvitamin D have been correlated with many health conditions, including chronic pain. Recent clinical practice guidelines define vitamin D levels < 20 ng/mL as deficient and values of 21–29 ng/mL as insufficient. Vitamin D insufficiency, including the most severe levels of deficiency, is more prevalent in black Americans. Ethnic and race group differences have been reported in both clinical and experimental pain, with black Americans reporting increased pain. The purpose of this study was to examine whether variation in vitamin D levels contribute to race differences in knee osteoarthritic pain. Methods The sample consisted of 94 participants (75% female), including 45 blacks and 49 whites with symptomatic knee osteoarthritis. Average age was 55.8 years (range 45–71 years). Participants completed a questionnaire on knee osteoarthritic symptoms and underwent quantitative sensory testing, including measures of heat and mechanical pain sensitivity. Results Blacks had significantly lower levels of vitamin D compared to whites, demonstrated greater clinical pain, and showed greater sensitivity to mechanical and heat pain. Low levels of vitamin D predicted increased experimental pain sensitivity, but did not predict self-reported clinical pain. Group differences in vitamin D significantly predicted group differences in heat pain and pressure pain thresholds on the index knee and ipsilateral forearm. Conclusion These data demonstrate race differences in experimental pain are mediated by differences in vitamin D level. Vitamin D deficiency may be a risk factor for increased knee osteoarthritic pain in black Americans. PMID:23135697
2011-01-01
Background Neck-shoulder pain conditions, e.g., chronic trapezius myalgia, have been associated with sensory disturbances such as increased sensitivity to experimentally induced pain. This study investigated pain sensitivity in terms of bilateral pressure pain thresholds over the trapezius and tibialis anterior muscles and pain responses after a unilateral hypertonic saline infusion into the right legs tibialis anterior muscle and related those parameters to intensity and area size of the clinical pain and to psychological factors (sleeping problems, depression, anxiety, catastrophizing and fear-avoidance). Methods Nineteen women with chronic non-traumatic neck-shoulder pain but without simultaneous anatomically widespread clinical pain (NSP) and 30 age-matched pain-free female control subjects (CON) participated in the study. Results NSP had lower pressure pain thresholds over the trapezius and over the tibialis anterior muscles and experienced hypertonic saline-evoked pain in the tibialis anterior muscle to be significantly more intense and locally more widespread than CON. More intense symptoms of anxiety and depression together with a higher disability level were associated with increased pain responses to experimental pain induction and a larger area size of the clinical neck-shoulder pain at its worst. Conclusion These results indicate that central mechanisms e.g., central sensitization and altered descending control, are involved in chronic neck-shoulder pain since sensory hypersensitivity was found in areas distant to the site of clinical pain. Psychological status was found to interact with the perception, intensity, duration and distribution of induced pain (hypertonic saline) together with the spreading of clinical pain. The duration and intensity of pain correlated negatively with pressure pain thresholds. PMID:21992460
Experimental human pain models in gastro-esophageal reflux disease and unexplained chest pain
Drewes, Asbjørn Mohr; Arendt-Nielsen, Lars; Funch-Jensen, Peter; Gregersen, Hans
2006-01-01
Methods related to experimental human pain research aim at activating different nociceptors, evoke pain from different organs and activate specific pathways and mechanisms. The different possibilities for using mechanical, electrical, thermal and chemical methods in visceral pain research are discussed with emphasis of combinations (e.g., the multimodal approach). The methods have been used widely in assessment of pain mechanisms in the esophagus and have contributed to our understanding of the symptoms reported in these patients. Hence abnormal activation and plastic changes of central pain pathways seem to play a major role in the symptoms in some patients with gastro-esophageal reflux disease and in patients with functional chest pain of esophageal origin. These findings may lead to an alternative approach for treatment in patients that does not respond to conventional medical or surgical therapy. PMID:16718803
Rice, David A; McNair, Peter J; Lewis, Gwyn N; Mannion, Jamie
2015-09-12
Populations with knee joint damage, including arthritis, have noted impairments in the regulation of submaximal muscle force. It is difficult to determine the exact cause of such impairments given the joint pathology and associated neuromuscular adaptations. Experimental pain models that have been used to isolate the effects of pain on muscle force regulation have shown impaired force steadiness during acute pain. However, few studies have examined force regulation during dynamic contractions, and these findings have been inconsistent. The goal of the current study was to examine the effect of experimental knee joint pain on submaximal quadriceps force regulation during isometric and dynamic contractions. The study involved fifteen healthy participants. Participants were seated in an isokinetic dynamometer. Knee extensor force matching tasks were completed in isometric, eccentric, and concentric muscle contraction conditions. The target force was set to 10 % of maximum for each contraction type. Hypertonic saline was then injected into the infrapatella fat pad to generate acute joint pain. The force matching tasks were repeated during pain and once more 5 min after pain had subsided. Hypertonic saline resulted in knee pain with an average peak pain rating of 5.5 ± 2.1 (0-10 scale) that lasted for 18 ± 4 mins. Force steadiness significantly reduced during pain across all three muscle contraction conditions. There was a trend to increased force matching error during pain but this was not significant. Experimental knee pain leads to impaired quadriceps force steadiness during isometric, eccentric, and concentric contractions, providing further evidence that joint pain directly affects motor performance. Given the established relationship between submaximal muscle force steadiness and function, such an effect may be detrimental to the performance of tasks in daily life. In order to restore motor performance in people with painful arthritic conditions of the
Vuilleumier, Pascal H.; Besson, Marie; Desmeules, Jules; Arendt-Nielsen, Lars; Curatolo, Michele
2013-01-01
Background and Aims Compounds that act on GABA-receptors produce anti-hyperalgesia in animal models, but little is known on their effects in humans. The aim of this study was to explore the potential usefulness of GABA-agonism for the control of pain in humans. Two agonists at the benzodiazepine-binding site of GABAA-receptors (clobazam and clonazepam) were studied using multiple experimental pain tests. Positive results would support further investigation of GABA agonism for the control of clinical pain. Methods In a randomized double-blind crossover design, 16 healthy male volunteers received clobazam 20 mg, clonazepam 1 mg and tolterodine 1 mg (active placebo). The area of static hyperalgesia after intradermal capsaicin injection was the primary endpoint. Secondary endpoints were: area of dynamic hyperalgesia, response to von Frey hair stimulation, pressure pain thresholds, conditioned pain modulation, cutaneous and intramuscular electrical pain thresholds (1, 5 and 20 repeated stimulation), and pain during cuff algometry. Results For the primary endpoint, an increase in the area of static hyperalgesia was observed after administration of placebo (p<0.001), but not after clobazam and clonazepam. Results suggestive for an anti-hyperalgesic effect of the benzodiazepines were obtained with all three intramuscular pain models and with cuff algometry. No effect could be detected with the other pain models employed. Conclusions Collectively, the results are suggestive for a possible anti-hyperalgesic effect of drugs acting at the GABAA-receptors in humans, particularly in models of secondary hyperalgesia and deep pain. The findings are not conclusive, but support further clinical research on pain modulation by GABAergic drugs. Because of the partial results, future research should focus on compounds acting selectively on subunits of the GABA complex, which may allow the achievement of higher receptor occupancy than unselective drugs. Our data also provide information
Masseter motor unit recruitment is altered in experimental jaw muscle pain.
Minami, I; Akhter, R; Albersen, I; Burger, C; Whittle, T; Lobbezoo, F; Peck, C C; Murray, G M
2013-02-01
Some management strategies for chronic orofacial pain are influenced by models (e.g., Vicious Cycle Theory, Pain Adaptation Model) proposing either excitation or inhibition within a painful muscle. The aim of this study was to determine if experimental painful stimulation of the masseter muscle resulted in only increases or only decreases in masseter activity. Recordings of single-motor-unit (SMU, basic functional unit of muscle) activity were made from the right masseters of 10 asymptomatic participants during biting trials at the same force level and direction under infusion into the masseter of isotonic saline (no-pain condition), and in another block of biting trials on the same day, with 5% hypertonic saline (pain condition). Of the 36 SMUs studied, 2 SMUs exhibited a significant (p < 0.05) increase, 5 a significant decrease, and 14 no significant change in firing rate during pain. Five units were present only during the no-pain block and 10 units during the pain block only. The findings suggest that, rather than only excitation or only inhibition within a painful muscle, a re-organization of activity occurs, with increases and decreases occurring within the painful muscle. This suggests the need to re-assess management strategies based on models that propose uniform effects of pain on motor activity.
Influence of intramuscular granisetron on experimentally induced muscle pain by acidic saline.
Louca, S; Ernberg, M; Christidis, N
2013-06-01
The aim of this study was to investigate whether intramuscular administration of the 5-HT(3) receptor antagonist granisetron reduces experimental muscle pain induced by repeated intramuscular injections of acidic saline into the masseter muscles. Twenty-eight healthy and pain-free volunteers, fourteen women and fourteen men participated in this randomized, double-blind and placebo-controlled study. After a screening examination and registration of the baseline pressure-pain threshold (PPT), the first simultaneous bilateral injections of 0·5 mL acidic saline (9 mg mL(-1) , pH 3·3) into the masseter muscles were performed. Two days later, PPT and pain (VAS) were re-assessed. The masseter muscle was then pre-treated with 0·5 mL granisetron (Kytril(®) 1 mg mL(-1) pH 5·3) on one side and control substance (isotonic saline, 9 mg mL(-1) pH 6) on the contralateral side. Two minutes thereafter a bilateral simultaneous injection of 0·5 mL acidic saline followed. The evoked pain intensity, pain duration, pain area and PPT were assessed. The volunteers returned 1 week later to re-assess VAS and PPT. On the side pre-treated with granisetron, the induced pain had significantly lower intensity and shorter duration (P < 0·05) compared with the side pre-treated with control. A subgroup analysis showed that the effect of granisetron on pain duration was significant only in women (P < 0·001), while the effect on peak pain and pain area were significant in both sexes. The results showed no significant change in PPT. In conclusion, these results indicate that granisetron has a pain-reducing effect on experimentally induced muscle pain by repeated acidic saline injection. © 2013 John Wiley & Sons Ltd.
Jess, Gunnar; Pogatzki-Zahn, Esther M; Zahn, Peter K; Meyer-Frießem, Christine H
2016-02-01
Pain assessment using a numerical rating scale (NRS) is considered good clinical practice, but objective assessment in noncommunicating patients is still a challenge. A potential solution is to monitor changes in heart rate variability transformed into the analgesia nociception index (ANI), that offers a noninvasive means of pain quantification. The aim was to measure magnitudes, descending slopes and time courses of ANI following expected and unexpected painful, nonpainful and sham experimental stimuli and compare these with pain intensity as assessed by NRS in conscious human volunteers. We expected a negative correlation between ANI and NRS after painful stimuli. Randomised stimuli and placebo-controlled, single-blinded study. Experimental pain simulation laboratory, Bochum, Germany. Twenty healthy male students, (mean ± standard deviation; 24.2 ± 1.9 years) recruited via local advertising, were consecutively included. ANI values were continuously recorded. After resting, four stimuli were applied in a random order on the right forearm (unexpected and expected electrical pain, expected nonpainful and sham stimuli). Blinded volunteers were asked to rate all four stimuli on NRS. ANI means (0-100), amplitudes, maxima, minima and slopes with NRS pain intensity scores (0-10). Resting alert volunteers showed ANI values of 82.05 ± 10.71. ANI decreased after a random stimulus (maximal decrease of 25.0 ± 7.3%), but different kinds of stimuli evoked similar results. NRS scores (median; interquartiles) were significantly (P = 0.008) higher after expected (5.25; 3.5-6.75) compared with unexpected (4.50; 3.0-5.0) pain stimuli. No correlation was found between ANI and NRS. ANI did not allow a differentiation of painful, nonpainful or sham stimuli in alert volunteers. Therefore, ANI does not exclusively detect nociception, but may be modified by stress and emotion. Thus, we conclude that ANI is not a specific, robust measure for assessment of pain
Tanasescu, Radu; Cottam, William J; Condon, Laura; Tench, Christopher R; Auer, Dorothee P
2016-09-01
Maladaptive mechanisms of pain processing in chronic pain conditions (CP) are poorly understood. We used coordinate based meta-analysis of 266 fMRI pain studies to study functional brain reorganisation in CP and experimental models of hyperalgesia. The pattern of nociceptive brain activation was similar in CP, hyperalgesia and normalgesia in controls. However, elevated likelihood of activation was detected in the left putamen, left frontal gyrus and right insula in CP comparing stimuli of the most painful vs. other site. Meta-analysis of contrast maps showed no difference between CP, controls, mood conditions. In contrast, experimental hyperalgesia induced stronger activation in the bilateral insula, left cingulate and right frontal gyrus. Activation likelihood maps support a shared neural pain signature of cutaneous nociception in CP and controls. We also present a double dissociation between neural correlates of transient and persistent pain sensitisation with general increased activation intensity but unchanged pattern in experimental hyperalgesia and, by contrast, focally increased activation likelihood, but unchanged intensity, in CP when stimulated at the most painful body part. Copyright © 2016. Published by Elsevier Ltd.
Experimental masseter muscle pain alters jaw-neck motor strategy.
Wiesinger, B; Häggman-Henrikson, B; Hellström, F; Wänman, A
2013-08-01
A functional integration between the jaw and neck regions has been demonstrated during normal jaw function. The effect of masseter muscle pain on this integrated motor behaviour in man is unknown. The aim of this study was to investigate the effect of induced masseter muscle pain on jaw-neck movements during a continuous jaw opening-closing task. Sixteen healthy men performed continuous jaw opening-closing movements to a target position, defined as 75% of the maximum jaw opening. Each subject performed two trials without pain (controls) and two trials with masseter muscle pain, induced with hypertonic saline as a single injection. Simultaneous movements of the mandible and the head were registered with a wireless optoelectronic three-dimensional recording system. Differences in movement amplitudes between trials were analysed with Friedman's test and corrected Wilcoxon matched pairs test. The head movement amplitudes were significantly larger during masseter muscle pain trials compared with control. Jaw movement amplitudes did not differ significantly between any of the trials after corrected Wilcoxon tests. The ratio between head and jaw movement amplitudes was significantly larger during the first pain trial compared with control. Experimental masseter muscle pain in humans affected integrated jaw-neck movements by increasing the neck component during continuous jaw opening-closing tasks. The findings indicate that pain can alter the strategy for jaw-neck motor control, which further underlines the functional integration between the jaw and neck regions. This altered strategy may have consequences for development of musculoskeletal pain in the jaw and neck regions. © 2012 European Federation of International Association for the Study of Pain Chapters.
Sturgeon, John A.; Johnson, Kevin A.
2017-01-01
Pain catastrophizing, a pattern of negative cognitive-emotional responses to actual or anticipated pain, maintains chronic pain and undermines response to treatments. Currently, precisely how pain catastrophizing influences pain processing is not well understood. In experimental settings, pain catastrophizing has been associated with amplified pain processing. This study sought to clarify pain processing mechanisms via experimental induction of pain catastrophizing. Forty women with chronic low back pain were assigned in blocks to an experimental condition, either a psychologist-led 10-minute pain catastrophizing induction or a control (10-minute rest period). All participants underwent a baseline round of several quantitative sensory testing (QST) tasks, followed by the pain catastrophizing induction or the rest period, and then a second round of the same QST tasks. The catastrophizing induction appeared to increase state pain catastrophizing levels. Changes in QST pain were detected for two of the QST tasks administered, weighted pin pain and mechanical allodynia. Although there is a need to replicate our preliminary results with a larger sample, study findings suggest a potential relationship between induced pain catastrophizing and central sensitization of pain. Clarification of the mechanisms through which catastrophizing affects pain modulatory systems may yield useful clinical insights into the treatment of chronic pain. PMID:28348505
Taub, Chloe J; Sturgeon, John A; Johnson, Kevin A; Mackey, Sean C; Darnall, Beth D
2017-01-01
Pain catastrophizing, a pattern of negative cognitive-emotional responses to actual or anticipated pain, maintains chronic pain and undermines response to treatments. Currently, precisely how pain catastrophizing influences pain processing is not well understood. In experimental settings, pain catastrophizing has been associated with amplified pain processing. This study sought to clarify pain processing mechanisms via experimental induction of pain catastrophizing. Forty women with chronic low back pain were assigned in blocks to an experimental condition, either a psychologist-led 10-minute pain catastrophizing induction or a control (10-minute rest period). All participants underwent a baseline round of several quantitative sensory testing (QST) tasks, followed by the pain catastrophizing induction or the rest period, and then a second round of the same QST tasks. The catastrophizing induction appeared to increase state pain catastrophizing levels. Changes in QST pain were detected for two of the QST tasks administered, weighted pin pain and mechanical allodynia. Although there is a need to replicate our preliminary results with a larger sample, study findings suggest a potential relationship between induced pain catastrophizing and central sensitization of pain. Clarification of the mechanisms through which catastrophizing affects pain modulatory systems may yield useful clinical insights into the treatment of chronic pain.
Endogenous Opioid Antagonism in Physiological Experimental Pain Models: A Systematic Review
Werner, Mads U.; Pereira, Manuel P.; Andersen, Lars Peter H.; Dahl, Jørgen B.
2015-01-01
Opioid antagonists are pharmacological tools applied as an indirect measure to detect activation of the endogenous opioid system (EOS) in experimental pain models. The objective of this systematic review was to examine the effect of mu-opioid-receptor (MOR) antagonists in placebo-controlled, double-blind studies using ʻinhibitoryʼ or ʻsensitizingʼ, physiological test paradigms in healthy human subjects. The databases PubMed and Embase were searched according to predefined criteria. Out of a total of 2,142 records, 63 studies (1,477 subjects [male/female ratio = 1.5]) were considered relevant. Twenty-five studies utilized ʻinhibitoryʼ test paradigms (ITP) and 38 studies utilized ʻsensitizingʼ test paradigms (STP). The ITP-studies were characterized as conditioning modulation models (22 studies) and repetitive transcranial magnetic stimulation models (rTMS; 3 studies), and, the STP-studies as secondary hyperalgesia models (6 studies), ʻpainʼ models (25 studies), summation models (2 studies), nociceptive reflex models (3 studies) and miscellaneous models (2 studies). A consistent reversal of analgesia by a MOR-antagonist was demonstrated in 10 of the 25 ITP-studies, including stress-induced analgesia and rTMS. In the remaining 14 conditioning modulation studies either absence of effects or ambiguous effects by MOR-antagonists, were observed. In the STP-studies, no effect of the opioid-blockade could be demonstrated in 5 out of 6 secondary hyperalgesia studies. The direction of MOR-antagonist dependent effects upon pain ratings, threshold assessments and somatosensory evoked potentials (SSEP), did not appear consistent in 28 out of 32 ʻpainʼ model studies. In conclusion, only in 2 experimental human pain models, i.e., stress-induced analgesia and rTMS, administration of MOR-antagonist demonstrated a consistent effect, presumably mediated by an EOS-dependent mechanisms of analgesia and hyperalgesia. PMID:26029906
Ethnicity Interacts with the OPRM1 Gene in Experimental Pain Sensitivity
Hastie, Barbara A.; Riley, Joseph L.; Kaplan, Lee; Herrera, Dyanne G.; Campbell, Claudia M.; Virtusio, Kathrina; Mogil, Jeffrey S.; Wallace, Margaret R.; Fillingim, Roger B.
2013-01-01
Robust inter-individual variation in pain sensitivity has been observed and recent evidence suggests that some of the variability may be genetically-mediated. Our previous data revealed significantly higher pressure pain thresholds among individuals possessing the minor G allele of the A118G SNP of the mu-opioid receptor gene (OPRM1) compared to those with two consensus alleles. Moreover, ethnic differences in pain sensitivity have been widely reported. Yet, little is known about the potential interactive associations of ethnicity and genotype with pain perception. This study aimed to identify ethnic differences in OPRM1 allelic associations with experimental pain responses. Two-hundred and forty-seven healthy young adults from three ethnic groups (81 African Americans; 79 non-white Hispanics; and 87 non-Hispanic whites) underwent multiple experimental pain modalities (thermal, pressure, ischemic, cold pressor). Few African Americans (7.4%) expressed the rare allele of OPRM1 compared to non-Hispanic-whites and Hispanics (28.7% vs. 27.8%, respectively). Across the entire sample, OPRM1 genotype did not significantly affect pain sensitivity. However, analysis in each ethnic group separately revealed significant genotype effects for most pain modalities among non-Hispanic-whites (ps<0.05) but not Hispanics or African Americans. The G allele was associated with decreased pain sensitivity among whites only; a trend in the opposite direction emerged in Hispanics. The reasons for this dichotomy are unclear but may involve ethnic differences in haplotypic structure or A118G may be a tag-SNP linked to other functional polymorphisms. These findings demonstrate an ethnic-dependent association of OPRM1 genotype with pain sensitivity. Additional research is warranted to uncover the mechanisms influencing these relationships. PMID:22717102
Does catastrophic thinking enhance oesophageal pain sensitivity? An experimental investigation.
Martel, M O; Olesen, A E; Jørgensen, D; Nielsen, L M; Brock, C; Edwards, R R; Drewes, A M
2016-09-01
Gastro-oesophageal reflux disease (GORD) is a major health problem that is frequently accompanied by debilitating oesophageal pain symptoms. The first objective of the study was to examine the association between catastrophizing and oesophageal pain sensitivity. The second objective was to examine whether catastrophizing was associated with the magnitude of acid-induced oesophageal sensitization. Twenty-five healthy volunteers (median age: 24.0 years; range: 22-31) were recruited and were asked to complete the Pain Catastrophizing Scale (PCS). During two subsequent study visits, mechanical, thermal, and electrical pain sensitivity in the oesophagus was assessed before and after inducing oesophageal sensitization using a 30-min intraluminal oesophageal acid perfusion procedure. Analyses were conducted based on data averaged across the two study visits. At baseline, catastrophizing was significantly associated with mechanical (r = -0.42, p < 0.05) and electrical (r = -0.60, p < 0.01) pain thresholds. After acid perfusion, catastrophizing was also significantly associated with mechanical (r = -0.58, p < 0.01) and electrical (r = -0.50, p < 0.05) pain thresholds. Catastrophizing was not significantly associated with thermal pain thresholds. Subsequent analyses revealed that catastrophizing was not significantly associated with the magnitude of acid-induced oesophageal sensitization. Taken together, findings from the present study suggest that catastrophic thinking exerts an influence on oesophageal pain sensitivity, but not necessarily on the magnitude of acid-induced oesophageal sensitization. WHAT DOES THIS STUDY ADD?: Catastrophizing is associated with heightened pain sensitivity in the oesophagus. This was substantiated by assessing responses to noxious stimulation of the oesophagus using an experimental paradigm mimicking features and symptoms experienced by patients with gastro-oesophageal reflux disease (GORD). © 2016 European Pain Federation
The role of periodontal ASIC3 in orofacial pain induced by experimental tooth movement in rats.
Gao, Meiya; Long, Hu; Ma, Wenqiang; Liao, Lina; Yang, Xin; Zhou, Yang; Shan, Di; Huang, Renhuan; Jian, Fan; Wang, Yan; Lai, Wenli
2016-12-01
This study aimed to clarify the roles of Acid-sensing ion channel 3 (ASIC3) in orofacial pain following experimental tooth movement. Sixty male Sprague-Dawley rats were divided into the experimental group (40g, n = 30) and the sham group (0g, n = 30). Closed coil springs were ligated between maxillary incisor and molars to achieve experimental tooth movement. Rat grimace scale (RGS) scores were assessed at 0, 1, 3, 5, 7, and 14 days after the placement of the springs. ASIC3 immunostaining was performed and the expression levels of ASIC3 were measured through integrated optical density/area in Image-Pro Plus 6.0. Moreover, 18 rats were divided into APETx2 group (n = 6), amiloride group (n = 6), and vehicle group (n = 6), and RGS scores were obtained compared among them to verify the roles of ASIC3 in orofacial pain following tooth movement. ASIC3 expression levels became significantly higher in the experimental group than in sham group on 1, 3, and 5 days and became similar on 7 and 14 days. Pain levels (RGS scores) increased in both groups and were significantly higher in the experimental group on 1, 3, 5, and 7 days and were similar on 14 days. Periodontal ASIC3 expression levels were correlated with orofacial pain levels following experimental tooth movement. Periodontal administrations of ASIC3 antagonists (APETx2 and amiloride) could alleviate pain. This study needs to be better evidenced by RNA interference of ASIC3 in periodontal tissues in rats following experimental tooth movement. Moreover, we hope further studies would concentrate on the pain perception of ASIC3 knockout (ASIC3 -/- ) mice. Our results suggest that periodontal ASIC3 plays an important role in orofacial pain induced by experimental tooth movement. © The Author 2015. Published by Oxford University Press on behalf of the European Orthodontic Society. All rights reserved. For permissions, please email: journals.permissions@oup.com.
Phillips, Jane L; Heneka, Nicole; Hickman, Louise; Lam, Lawrence; Shaw, Tim
2014-06-01
Pain is a complex multidimensional phenomenon moderated by consumer, provider and health system factors. Effective pain management cuts across professional boundaries, with failure to screen and assess contributing to the burden of unrelieved pain. To test the impact of an online pain assessment learning module on specialist palliative care nurses' pain assessment competencies, and to determine whether this education impacted positively on palliative care patients' reported pain ratings. A quasi-experimental pain assessment education pilot study utilising 'Qstream © ', an online methodology to deliver 11 case-based pain assessment learning scenarios, developed by an interdisciplinary expert panel and delivered to participants' work emails over a 28-day period in mid-2012. The 'Self-Perceived Pain Assessment Competencies' survey and chart audit data, including patient-reported pain intensity ratings, were collected pre-intervention (T1) and post-intervention (T2) and analysed using inferential statistics to determine key outcomes. Nurses working at two Australian inpatient specialist palliative care services in 2012. The results reported conform to the Strengthening the Reporting of Observational Studies in Epidemiology (STROBE) Guidelines. Participants who completed the education intervention ( n = 34) increased their pain assessment knowledge, assessment tool knowledge and confidence to undertake a pain assessment ( p < 0.001). Participants were more likely to document pain intensity scores in patients' medical records than non-participants (95% confidence interval = 7.3%-22.7%, p = 0.021). There was also a significant reduction in the mean patient-reported pain ratings between the admission and audit date at post-test of 1.5 (95% confidence interval = 0.7-2.3) units in pain score. This pilot confers confidence of the education interventions capacity to improve specialist palliative care nurses' pain assessment practices and to reduce patient-rated pain intensity
Oertel, Bruno Georg; Lötsch, Jörn
2013-01-01
The medical impact of pain is such that much effort is being applied to develop novel analgesic drugs directed towards new targets and to investigate the analgesic efficacy of known drugs. Ongoing research requires cost-saving tools to translate basic science knowledge into clinically effective analgesic compounds. In this review we have re-examined the prediction of clinical analgesia by human experimental pain models as a basis for model selection in phase I studies. The overall prediction of analgesic efficacy or failure of a drug correlated well between experimental and clinical settings. However, correct model selection requires more detailed information about which model predicts a particular clinical pain condition. We hypothesized that if an analgesic drug was effective in an experimental pain model and also a specific clinical pain condition, then that model might be predictive for that particular condition and should be selected for development as an analgesic for that condition. The validity of the prediction increases with an increase in the numbers of analgesic drug classes for which this agreement was shown. From available evidence, only five clinical pain conditions were correctly predicted by seven different pain models for at least three different drugs. Most of these models combine a sensitization method. The analysis also identified several models with low impact with respect to their clinical translation. Thus, the presently identified agreements and non-agreements between analgesic effects on experimental and on clinical pain may serve as a solid basis to identify complex sets of human pain models that bridge basic science with clinical pain research. PMID:23082949
Iacovides, S; Avidon, I; Baker, F C
2015-07-01
Monthly primary dysmenorrhoeic pain is associated with increased sensitivity to painful stimuli, particularly in deep tissue. We investigated whether women with dysmenorrhoea, compared with controls, have increased sensitivity to experimentally induced deep-tissue muscle ischaemia in a body area distant from that of referred menstrual pain. The sub-maximal effort tourniquet test was used to induce forearm ischaemia in 11 women with severe dysmenorrhoea and in nine control women both during menstruation and in the follicular phase of the menstrual cycle. Von Frey hair assessments confirmed the presence of experimental ischaemia. Women rated the intensity of menstrual and ischaemic pain on a 100-mm visual analogue scale. Women with dysmenorrhoea [mean (SD): 68 (20) mm] reported significantly greater menstrual pain compared with controls [mean (SD): 2 (6) mm; p = 0.0001] during the menstruation phase. They also rated their forearm ischaemic pain as significantly greater than the controls during the menstruation [dysmenorrhoeics vs. controls mean (SD): 58 (19) mm vs. 31 (21) mm, p < 0.01] and follicular [dysmenorrhoeics vs. controls mean (SD): 60 (18) mm vs. 40 (14) mm, p < 0.01] phases of the menstrual cycle. These data show that compared with controls, women who experience severe recurrent dysmenorrhoea have deep-tissue hyperalgesia to ischaemic pain in muscles outside of the referred area of menstrual pain both during the painful menstruation phase and pain-free follicular phase. These findings suggest the presence of long-lasting changes in muscle pain sensitivity in women with dysmenorrhoea. Our findings that dysmenorrhoeic women are hyperalgesic to a clinically relevant, deep-muscle ischaemic pain in areas outside of referred menstrual pain confirm other studies showing long-lasting changes in pain sensitivity outside of the painful period during menstruation. © 2014 European Pain Federation - EFIC®
Lai, Weng-Hang; Shih, Yi-Fen; Lin, Pei-Ling; Chen, Wen-Yin; Ma, Hsiao-Li
2012-12-01
To assess the specificity of the femoral slump test (FST) when assessing experimentally induced anterior knee pain. Cross-sectional, exploratory study. Research laboratory. Asymptomatic subjects (N=12; 6 men; 6 women) for the study. An experimental pain model was used to simulate anterior knee pain by injecting .25 mL of hypertonic saline solution (5% NaCl) into the medial infrapatellar fat pad. Not applicable. The changes in pain intensity and diameter after applying the structure differential maneuver (neck flexion/extension) during the FST were recorded and analyzed. Results revealed that the structure differential maneuver of the FST did not alter the pain intensity or diameter in 9 (neck extension) and 10 (neck flexion) out of 12 subjects, which meant that the FST provided appropriate testing responses in 75% to 83% cases when the anterior knee pain did not originate in neural tissues. The FST had a specificity of more than .75 when detecting nerve mechanosensitivity problems of anterior knee pain. Copyright © 2012 American Congress of Rehabilitation Medicine. Published by Elsevier Inc. All rights reserved.
The effects of experimental pain and induced optimism on working memory task performance.
Boselie, Jantine J L M; Vancleef, Linda M G; Peters, Madelon L
2016-07-01
Pain can interrupt and deteriorate executive task performance. We have previously shown that experimentally induced optimism can diminish the deteriorating effect of cold pressor pain on a subsequent working memory task (i.e., operation span task). In two successive experiments we sought further evidence for the protective role of optimism on pain-induced working memory impairments. We used another working memory task (i.e., 2-back task) that was performed either after or during pain induction. Study 1 employed a 2 (optimism vs. no-optimism)×2 (pain vs. no-pain)×2 (pre-score vs. post-score) mixed factorial design. In half of the participants optimism was induced by the Best Possible Self (BPS) manipulation, which required them to write and visualize about a life in the future where everything turned out for the best. In the control condition, participants wrote and visualized a typical day in their life (TD). Next, participants completed either the cold pressor task (CPT) or a warm water control task (WWCT). Before (baseline) and after the CPT or WWCT participants working memory performance was measured with the 2-back task. The 2-back task measures the ability to monitor and update working memory representation by asking participants to indicate whether the current stimulus corresponds to the stimulus that was presented 2 stimuli ago. Study 2 had a 2 (optimism vs. no-optimism)×2 (pain vs. no-pain) mixed factorial design. After receiving the BPS or control manipulation, participants completed the 2-back task twice: once with painful heat stimulation, and once without any stimulation (counter-balanced order). Continuous heat stimulation was used with temperatures oscillating around 1°C above and 1°C below the individual pain threshold. In study 1, the results did not show an effect of cold pressor pain on subsequent 2-back task performance. Results of study 2 indicated that heat pain impaired concurrent 2-back task performance. However, no evidence was found
2012-01-01
Background Although there is evidence that spinal manipulative therapy (SMT) can reduce pain, the mechanisms involved are not well established. There is a need to review the scientific literature to establish the evidence-base for the reduction of pain following SMT. Objectives To determine if SMT can reduce experimentally induced pain, and if so, if the effect is i) only at the level of the treated spinal segment, ii) broader but in the same general region as SMT is performed, or iii) systemic. Design A systematic critical literature review. Methods A systematic search was performed for experimental studies on healthy volunteers and people without chronic syndromes, in which the immediate effect of SMT was tested. Articles selected were reviewed blindly by two authors. A summary quality score was calculated to indicate level of manuscript quality. Outcome was considered positive if the pain-reducing effect was statistically significant. Separate evidence tables were constructed with information relevant to each research question. Results were interpreted taking into account their manuscript quality. Results Twenty-two articles were included, describing 43 experiments, primarily on pain produced by pressure (n = 27) or temperature (n = 9). Their quality was generally moderate. A hypoalgesic effect was shown in 19/27 experiments on pressure pain, produced by pressure in 3/9 on pain produced by temperature and in 6/7 tests on pain induced by other measures. Second pain provoked by temperature seems to respond to SMT but not first pain. Most studies revealed a local or regional hypoalgesic effect whereas a systematic effect was unclear. Manipulation of a “restricted motion segment” (“manipulable lesion”) seemed not to be essential to analgesia. In relation to outcome, there was no discernible difference between studies with higher vs. lower quality scores. Conclusions These results indicate that SMT has a direct local/regional hypoalgesic effect on
The influence of working memory capacity on experimental heat pain.
Nakae, Aya; Endo, Kaori; Adachi, Tomonori; Ikeda, Takashi; Hagihira, Satoshi; Mashimo, Takashi; Osaka, Mariko
2013-10-01
Pain processing and attention have a bidirectional interaction that depends upon one's relative ability to use limited-capacity resources. However, correlations between the size of limited-capacity resources and pain have not been evaluated. Working memory capacity, which is a cognitive resource, can be measured using the reading span task (RST). In this study, we hypothesized that an individual's potential working memory capacity and subjective pain intensity are related. To test this hypothesis, we evaluated 31 healthy participants' potential working memory capacity using the RST, and then applied continuous experimental heat stimulation using the listening span test (LST), which is a modified version of the RST. Subjective pain intensities were significantly lower during the challenging parts of the RST. The pain intensity under conditions where memorizing tasks were performed was compared with that under the control condition, and it showed a correlation with potential working memory capacity. These results indicate that working memory capacity reflects the ability to process information, including precise evaluations of changes in pain perception. In this work, we present data suggesting that changes in subjective pain intensity are related, depending upon individual potential working memory capacities. Individual working memory capacity may be a phenotype that reflects sensitivity to changes in pain perception. Copyright © 2013 American Pain Society. Published by Elsevier Inc. All rights reserved.
Hains, Guy; Boucher, Pierre B; Lamy, Anne-Marie
2015-03-01
The aim of this study was to evaluate the efficacy of myofascial therapy involving ischemic compression on trigger points in combination with mobilization therapy on patients with chronic nonspecific foot pain. Two quasi-experimental before-and-after studies involving two different baseline states. Foot pain patients at a private clinic were divided into two separate cohorts: A, custom orthotic users; and B, non-users. In Study A, 31 users received 15 experimental treatments consisting of ischemic compressions on trigger points and mobilization of articulations through the foot immediately after study enrollment. In study B, ten non-users were prescribed a soft prefabricated insole and were monitored for five weeks before subsequently receiving 15 experimental treatments after the initial five-week delay. The Foot Function Index (FFI) and patients' perceived improvement score (PIS) on a scale from 0% to 100%. The Study A group (n=31) maintained a significant reduction in the FFI at all three follow-up evaluations. Mean improvement from baseline in FFI was 47%, 49% and 56% at 0, 1 and 6 months, respectively, post-treatment. Mean PIS was 58%, 57%, and 58%, again at 0, 1 and 6 months post-treatment. For the Study B group, mean improvement in FFI was only 19% after the monitoring period, and 64% after the experimental treatment period. Mean PIS was 31% after monitoring, and 78% after experimental treatment. In repeated measures analyses, experimental treatment was associated with a significant main effect in both of these before-and after studies (all P values<0.01). Combined treatment involving ischemic compression and joint mobilization for chronic foot pain is associated with significant improvements in functional and self-perceived improvement immediately and at up to six-months post-treatment. Further validation of this treatment approach within a randomized controlled trial is needed.
Vigil, Jacob M; Rowell, Lauren N; Chouteau, Simone; Chavez, Alexandre; Jaramillo, Elisa; Neal, Michael; Waid, David
2013-01-01
This is the first study to examine how both structural and functional components of individuals' social networks may moderate the association between biological sex and experimental pain sensitivity. One hundred and fifty-two healthy adults (mean age = 22yrs., 53% males) were measured for cold pressor task (CPT) pain sensitivity (i.e., intensity ratings) and core aspects of social networks (e.g., proportion of friends vs. family, affection, affirmation, and aid). Results showed consistent sex differences in how social network structures and intimate relationship functioning modulated pain sensitivity. Females showed higher pain sensitivity when their social networks consisted of a higher proportion of intimate types of relationship partners (e.g., kin vs. non kin), when they had known their network partners for a longer period of time, and when they reported higher levels of logistical support from their significant other (e.g., romantic partner). Conversely, males showed distinct patterns in the opposite direction, including an association between higher levels of logistical support from one's significant other and lower CPT pain intensity. These findings show for the first time that the direction of sex differences in exogenous pain sensitivity is likely dependent on fundamental components of the individual's social environment. The utility of a social-signaling perspective of pain behaviors for examining, comparing, and interpreting individual and group differences in experimental and clinical pain reports is discussed.
Vigil, Jacob M.; Rowell, Lauren N.; Chouteau, Simone; Chavez, Alexandre; Jaramillo, Elisa; Neal, Michael; Waid, David
2013-01-01
This is the first study to examine how both structural and functional components of individuals’ social networks may moderate the association between biological sex and experimental pain sensitivity. One hundred and fifty-two healthy adults (mean age = 22yrs., 53% males) were measured for cold pressor task (CPT) pain sensitivity (i.e., intensity ratings) and core aspects of social networks (e.g., proportion of friends vs. family, affection, affirmation, and aid). Results showed consistent sex differences in how social network structures and intimate relationship functioning modulated pain sensitivity. Females showed higher pain sensitivity when their social networks consisted of a higher proportion of intimate types of relationship partners (e.g., kin vs. non kin), when they had known their network partners for a longer period of time, and when they reported higher levels of logistical support from their significant other (e.g., romantic partner). Conversely, males showed distinct patterns in the opposite direction, including an association between higher levels of logistical support from one’s significant other and lower CPT pain intensity. These findings show for the first time that the direction of sex differences in exogenous pain sensitivity is likely dependent on fundamental components of the individual’s social environment. The utility of a social-signaling perspective of pain behaviors for examining, comparing, and interpreting individual and group differences in experimental and clinical pain reports is discussed. PMID:24223836
Erfanian, Parham; Tenzif, Siamak; Guerriero, Rocco C
2004-01-01
Objective To determine the effects of a semi-customized experimental cervical pillow on symptomatic adults with chronic neck pain (with and without headache) during a four week study. Design A randomized controlled trial. Sample size Thirty-six adults were recruited for the trial, and randomly assigned to experimental or non-experimental groups of 17 and 19 participants respectively. Subjects Adults with chronic biomechanical neck pain who were recruited from the Canadian Memorial Chiropractic College (CMCC) Walk-in Clinic. Outcome measures Subjective findings were assessed using a mail-in self-report daily pain diary, and the CMCC Neck Disability Index (NDI). Statistical analysis Using repeated measure analysis of variance weekly NDI scores, average weekly AM and PM pain scores between the experimental and non-experimental groups were compared throughout the study. Results The experimental group had statistically significant lower NDI scores (p < 0.05) than the non-experimental group. The average weekly AM scores were lower and statistically significant (p < 0.05) in the experimental group. The PM scores in the experimental group were lower but not statistically significant than the other group. Conclusions The study results show that compared to conventional pillows, this experimental semi-customized cervical pillow was effective in reducing low-level neck pain intensity, especially in the morning following its use in a 4 week long study. PMID:17549216
Central Pain Processing in Early-Stage Parkinson's Disease: A Laser Pain fMRI Study
Petschow, Christine; Scheef, Lukas; Paus, Sebastian; Zimmermann, Nadine; Schild, Hans H.; Klockgether, Thomas; Boecker, Henning
2016-01-01
Background & Objective Pain is a common non-motor symptom in Parkinson’s disease. As dopaminergic dysfunction is suggested to affect intrinsic nociceptive processing, this study was designed to characterize laser-induced pain processing in early-stage Parkinson’s disease patients in the dopaminergic OFF state, using a multimodal experimental approach at behavioral, autonomic, imaging levels. Methods 13 right-handed early-stage Parkinson’s disease patients without cognitive or sensory impairment were investigated OFF medication, along with 13 age-matched healthy control subjects. Measurements included warmth perception thresholds, heat pain thresholds, and central pain processing with event-related functional magnetic resonance imaging (erfMRI) during laser-induced pain stimulation at lower (E = 440 mJ) and higher (E = 640 mJ) target energies. Additionally, electrodermal activity was characterized during delivery of 60 randomized pain stimuli ranging from 440 mJ to 640 mJ, along with evaluation of subjective pain ratings on a visual analogue scale. Results No significant differences in warmth perception thresholds, heat pain thresholds, electrodermal activity and subjective pain ratings were found between Parkinson’s disease patients and controls, and erfMRI revealed a generally comparable activation pattern induced by laser-pain stimuli in brain areas belonging to the central pain matrix. However, relatively reduced deactivation was found in Parkinson’s disease patients in posterior regions of the default mode network, notably the precuneus and the posterior cingulate cortex. Conclusion Our data during pain processing extend previous findings suggesting default mode network dysfunction in Parkinson’s disease. On the other hand, they argue against a genuine pain-specific processing abnormality in early-stage Parkinson’s disease. Future studies are now required using similar multimodal experimental designs to examine pain processing in more advanced
Korat, Prashant S; Kapupara, Pankaj P
2017-12-01
The body areas from where sutures are removed later, where wound healing is delayed. Epidural analgesia is the most effective method but could not be used for postoperative pain. Peripheral nerve blockers also provided excellent analgesia but are not effective in postoperative pain. Infiltration of the surgical wound with local anesthetics is decreased postoperative pain by inhibiting transmission of noxious impulses at the site. The objective of the study was to explore the effect of the local infiltration of the surgical wounds with low-dose of levobupivacaine, ibuprofen, and epinephrine over the sutured muscle wound in postoperative pain. Laparotomy was performed in adult rats under isoflurane anesthesia. During surgery, the surgical wounds were infiltrated with 50μL solution containing 0.3% w/v levobupivacaine, 2mg/mL ibuprofen, and 8mg/mL epinephrine (treatment group) and compared to infiltration of that of water for injection (vehicle group) over the sutured muscle wound before skin closing. Postoperative pain was assessed by rodent grimace scales scoring. The study also carried out for measurement for histopathological examinations and the tensile strength of wound. The one-way ANOVA following the Dunnett Multiple comparisons test was used to show significant differences between parameters at 95% level of confidence. The fall in pain started with three-hour post-surgery in the treatment group. At 24h after the end of the successful infiltration, the treatment group had significant reduction of a pain than vehicle group (p=0.048; q=3.527). After three weeks of the wound were closed, a significant improvement of angiogenesis process (p=0.021) and the tensile strength (p=0.019) for the treatment group as compared to baseline. The experimental study was reported that local infiltration of the surgical wound with levobupivacaine, ibuprofen, and epinephrine combination was effective in the postoperative pain and healing of the surgical wounds. Copyright © 2017
Cánovas Martínez, L; Orduña Valls, J; Paramés Mosquera, E; Lamelas Rodríguez, L; Rojas Gil, S; Domínguez García, M
2016-05-01
To compare the analgesic effects between the blockade and bipolar thermal radiofrequency in the treatment of sacroiliac joint pain. Prospective, randomised and experimental study conducted on 60 patients selected in the two hospitals over a period of nine months, who had intense sacroiliac joint pain (Visual Analogue Scale [VAS]>6) that lasted more than 3 months. Patients were randomised into three groups (n=20): Group A (two intra-articular sacroiliac injections of local anaesthetic/corticosteroid guided by ultrasound in 7 days). Group B: conventional bipolar radiofrequency "palisade". Target points were the lateral branch nerves of S1, S2, and S3, distance needles 1cm. Group C: modified bipolar radiofrequency "palisade" (needle distance >1cm). Patients were evaluated at one month, three months, and one year. Demographic data, VAS reduction, and side effects of the techniques were assessed. One month after the treatment, pain reduction was >50% in the three groups P<.001. Three and 12 months after the technique, the patients of the group A did not have a significant reduction in pain. At 3 months, almost 50% patients of the group B referred to improvement of the pain (P=.03), and <25% at 12 months, and those results were statistically significant (P=.01) compared to the baseline. Group C showed an improvement of 50% at 3 and 12 months (P<.001). All patients completed the study. Bipolar radiofrequency "palisade", especially when the distance between the needles was increased, was more effective and lasted longer, compared to join block and steroids, in relieving pain sacroiliac joint. Copyright © 2015 Sociedad Española de Anestesiología, Reanimación y Terapéutica del Dolor. Publicado por Elsevier España, S.L.U. All rights reserved.
Molina, Juliana; Amaro, Edson; da Rocha, Liana Guerra Sanches; Jorge, Liliana; Santos, Flavia Heloisa; Len, Claudio A
2017-11-14
Studies on functional magnetic resonance imaging (fMRI) have shown that adults with musculoskeletal pain syndromes tolerate smaller amount of pressure (pain) as well as differences in brain activation patterns in areas related to pain.The objective of this study was to evaluate, through fMRI, the brain activation in adolescents with idiopathic musculoskeletal pain (IMP) while performing an experimental paradigm of pain. The study included 10 consecutive adolescents with idiopathic musculoskeletal pain (average age 16.3±1.0) and 10 healthy adolescents age-matched. fMRI exams were performed in a 3 T scanner (Magnetom Trio, Siemens) using an event-related design paradigm. Pressure stimuli were performed in the nondominant hand thumb, divided into two stages, fixed pain and variable pain. The two local Research Ethics Committees (Ethics Committee from Universidade Federal de São Paulo- Brazil, process number 0688/11, on July 1st, 2011 and Ethics Committee from Hospital Israelita Albert Einsten - Brazil, process number 1673, on October 19th, 2011) approved the study. The idiopathic musculoskeletal pain (IMP) group showed a reduced threshold for pain (3.7 kg/cm 2 versus 4.45 kg/cm 2 , p = 0.005). Control group presented increased bain activation when compared to IMP group in the following areas: thalamus (p = 0.00001), precentral gyrus (p = 0.0004) and middle frontal gyrus (p = 0.03). In intragroup analysis, IMP group showed greater brain activation during the unpredictable stimuli of the variable pain stage, especially in the lingual gyrus (p = 0.0001), frontal lobe (p = 0.0001), temporal gyrus (p = 0.0001) and precentral gyrus (p = 0.03), when compared to predictable stimulus of fixed pain. The same intragroup analysis with the control group showed greater activation during the unpredictable stimuli in regions of the precentral gyrus (p = 0.0001), subcallosal area (p = 0.0001), right and left occipital fusiform gyrus (p
Wolf, Thomas Gerhard; Wolf, Dominik; Callaway, Angelika; Below, Dagna; d'Hoedt, Bernd; Willershausen, Brita; Daubländer, Monika
2016-01-01
This prospective randomized clinical crossover trial was designed to compare hypnosis and local anesthesia for experimental dental pain relief. Pain thresholds of the dental pulp were determined. A targeted standardized pain stimulus was applied and rated on the Visual Analogue Scale (0-10). The pain threshold was lower under hypnosis (58.3 ± 17.3, p < .001), maximal (80.0) under local anesthesia. The pain stimulus was scored higher under hypnosis (3.9 ± 3.8) than with local anesthesia (0.0, p < .001). Local anesthesia was superior to hypnosis and is a safe and effective method for pain relief in dentistry. Hypnosis seems to produce similar effects observed under sedation. It can be used in addition to local anesthesia and in individual cases as an alternative for pain control in dentistry.
The Role of Coping and Race in Healthy Children’s Experimental Pain Responses
Evans, Subhadra; Lu, Qian; Tsao, Jennie C. I.; Zelter, Lonnie K.
2009-01-01
This study examined the relationship between race, laboratory-based coping strategies and anticipatory anxiety and pain intensity for cold, thermal (heat) and pressure experimental pain tasks. Participants were 123 healthy children and adolescents, including 33 African Americans (51% female; mean age =13.9 years) and 90 Caucasians (50% female; mean age = 12.6 years). Coping in response to the cold task was assessed with the Lab Coping Style interview; based on their interview responses, participants were categorized as ‘attenders’ (i.e., those who focused on the task) vs. ‘distractors’ (i.e., those who distracted themselves during the task). Analysis of covariance (ANCOVA) revealed significant interactions between race (African-American vs. Caucasian) and lab-based coping style after controlling for sex, age and socioeconomic status. African-American children classified as attenders reported less anticipatory anxiety for the cold task and lower pain intensity for the cold, heat and pressure tasks compared to those categorized as distractors. For these pain outcomes, Caucasian children classified as distractors reported less anticipatory anxiety and lower pain intensity relative to those categorized as attenders. The findings point to the moderating effect of coping in the relationship between race and experimental pain sensitivity. PMID:20352035
Knopp, K L; Stenfors, C; Baastrup, C; Bannon, A W; Calvo, M; Caspani, O; Currie, G; Finnerup, N B; Huang, W; Kennedy, J D; Lefevre, I; Machin, I; Macleod, M; Rees, H; Rice, A S C; Rutten, K; Segerdahl, M; Serra, J; Wodarski, R; Berge, O-G; Treedef, R-D
2017-12-29
Background and aims Pain is a subjective experience, and as such, pre-clinical models of human pain are highly simplified representations of clinical features. These models are nevertheless critical for the delivery of novel analgesics for human pain, providing pharmacodynamic measurements of activity and, where possible, on-target confirmation of that activity. It has, however, been suggested that at least 50% of all pre-clinical data, independent of discipline, cannot be replicated. Additionally, the paucity of "negative" data in the public domain indicates a publication bias, and significantly impacts the interpretation of failed attempts to replicate published findings. Evidence suggests that systematic biases in experimental design and conduct and insufficiencies in reporting play significant roles in poor reproducibility across pre-clinical studies. It then follows that recommendations on how to improve these factors are warranted. Methods Members of Europain, a pain research consortium funded by the European Innovative Medicines Initiative (IMI), developed internal recommendations on how to improve the reliability of pre-clinical studies between laboratories. This guidance is focused on two aspects: experimental design and conduct, and study reporting. Results Minimum requirements for experimental design and conduct were agreed upon across the dimensions of animal characteristics, sample size calculations, inclusion and exclusion criteria, random allocation to groups, allocation concealment, and blinded assessment of outcome. Building upon the Animals in Research: Reportingin vivo Experiments (ARRIVE) guidelines, reporting standards were developed for pre-clinical studies of pain. These include specific recommendations for reporting on ethical issues, experimental design and conduct, and data analysis and interpretation. Key principles such as sample size calculation, a priori definition of a primary efficacy measure, randomization, allocation concealments
Borglin, Gunilla; Gustafsson, Markus; Krona, Hans
2011-09-23
Pain is one of the most frequent problems among patients diagnosed with cancer. Despite the availability of effective pharmacological treatments, this group of patients often receives less than optimal treatment. Research into nurses' pain management highlights certain factors, such as lack of knowledge and attitudes and inadequate procedures for systematic pain assessment, as common barriers to effective pain management. However, educational interventions targeting nurses' pain management have shown promise. As cancer-related pain is also known to have a negative effect on vital aspects of the patient's life, as well as being commonly associated with problems such as sleep, fatigue, depression and anxiety, further development of knowledge within this area is warranted. A quasi-experimental study design will be used to investigate whether the implementation of guidelines for systematic daily pain assessments following a theory-based educational intervention will result in an improvement in knowledge and attitude among nurses. A further aim is to investigate whether the intervention that targets nurses' behaviour will improve hospital patients' perception of pain. Data regarding nurses' knowledge and attitudes to pain (primary outcome), patient perception regarding pain (secondary outcome), together with socio-demographic variables, will be collected at baseline and at four weeks and 12 weeks following the intervention. Nursing care is nowadays acknowledged as an increasingly complicated activity and "nursing complexity is such that it can be seen as the quintessential complex intervention." To be able to change and improve clinical practice thus requires multiple points of attack appropriate to meet complex challenges. Consequently, we expect the theory-based intervention used in our quasi-experimental study to improve care as well as quality of life for this group of patients and we also envisage that evidence-based guidelines targeting this patient group's pain
Birnie, Kathryn A; Caes, Line; Wilson, Anna C; Williams, Sara E; Chambers, Christine T
2014-01-01
SUMMARY Use of experimental pain is vital for addressing research questions that would otherwise be impossible to examine in the real world. Experimental induction of pain in children is highly scrutinized given the potential for harm and lack of direct benefit to a vulnerable population. However, its use has critically advanced our understanding of the mechanisms, assessment and treatment of pain in both healthy and chronically ill children. This article introduces various experimental pain modalities, including the cold pressor task, the water load symptom provocation test, thermal pain, pressure pain and conditioned pain modulation, and discusses their application for use with children and adolescents. It addresses practical implementation and ethical issues, as well as the advantages and disadvantages offered by each task. The incredible potential for future research is discussed given the array of experimental pain modalities now available to pediatric researchers. PMID:24641434
Pain empathy in schizophrenia: an fMRI study
Jimenez, Amy M.; Lee, Junghee; Wynn, Jonathan K.; Eisenberger, Naomi I.; Green, Michael F.
2016-01-01
Abstract Although it has been proposed that schizophrenia is characterized by impaired empathy, several recent studies found intact neural responses on tasks measuring the affective subdomain of empathy. This study further examined affective empathy in 21 schizophrenia outpatients and 21 healthy controls using a validated pain empathy paradigm with two components: (i) observing videos of people described as medical patients who were receiving a painful sound stimulation treatment; (ii) listening to the painful sounds (to create regions of interest). The observing videos component incorporated experimental manipulations of perspective taking (instructions to imagine ‘Self’ vs ‘Other’ experiencing pain) and cognitive appraisal (information about whether treatment was ‘Effective’ vs ‘Not Effective’). When considering activation across experimental conditions, both groups showed similar dorsal anterior cingulate cortex (dACC) and anterior insula (AI) activation while merely observing others in pain. However, there were group differences associated with perspective taking: controls showed relatively greater dACC and AI activation for the Self vs Other contrast whereas patients showed relatively greater activation in these and additional regions for the Other vs Self contrast. Although patients demonstrated grossly intact neural activity while observing others in pain, they showed more subtle abnormalities when required to toggle between imagining themselves vs others experiencing pain. PMID:26746181
Sharpe, L; Johnson, A; Dear, B F
2015-10-01
The aim of this study was to compare the effectiveness of training participants' attention towards or away from painful faces versus pain-related words on pain outcomes on an acute experimental pain paradigm. Participants were randomized to receive either training towards or away from painful faces or words. Following training, participants completed the cold pressor task. The results confirm that attention bias modification produced the predicted changes in attentional biases. Clear training effects were observed for words and faces, such that attentional biases changed in the predicted direction on the stimuli presented during the training. However, for those trained on words, training effects also generalized to face stimuli. As predicted, those who received training away from painful stimuli took longer to report pain (higher pain threshold) during the cold pressor task, and this effect was more pronounced for those trained on words. Contrary to expectations, those trained on faces (regardless of training direction) reported less pain than those trained on words. There were no differences between the groups for pain tolerance (length of time participants were able to keep their arms in the cold pressor). These findings confirm that attentional biases are modifiable, and impact (in the expected manner) how quickly participants perceive pain. Further, exposure to painful faces resulted in additional benefits to the level of pain reported. However, we were unable to confirm that change in attentional biases was the mechanism of change. © 2014 European Pain Federation - EFIC®
Acute experimental hip muscle pain alters single-leg squat balance in healthy young adults.
Hatton, Anna L; Crossley, Kay M; Hug, François; Bouma, James; Ha, Bonnie; Spaulding, Kara L; Tucker, Kylie
2015-05-01
Clinical musculoskeletal pain commonly accompanies hip pathology and can impact balance performance. Due to the cross-sectional designs of previous studies, and the multifactorial nature of musculoskeletal pain conditions, it is difficult to determine whether pain is a driver of balance impairments in this population. This study explored the effects of experimentally induced hip muscle pain on static and dynamic balance. Twelve healthy adults (4 women, mean[SD]: 27.1[3] years) performed three balance tasks on each leg, separately: single-leg standing (eyes closed), single-leg squat (eyes open), forward step (eyes open); before and after hypertonic saline injection (1ml, 5% NaCl) into the right gluteus medius. Range, standard deviation (SD), and velocity of the centre of pressure (CoP) in medio-lateral (ML) and anterior-posterior (AP) directions were considered. During the single-leg squat task, experimental hip pain was associated with significantly reduced ML range (-4[13]%, P=0.028), AP range (-14[21]%, P=0.005), APSD (-15[28]%, P=0.009), and AP velocity (-6[13]%, P=0.032), relative to the control condition, in both legs. No effect of pain was observed during single-leg standing and forward stepping. Significant between-leg differences in ML velocity were observed during the forward stepping task (P=0.034). Pain is a potentially modifiable patient-reported outcome in individuals with hip problems. This study demonstrates that acute hip muscle pain alone, without interference of musculoskeletal pathology, does not lead to the same impairments in balance as exhibited in clinical populations with hip pathologies. This is the first step in understanding how and why balance is altered in painful hip pathologies. Copyright © 2015 Elsevier B.V. All rights reserved.
Van Oosterwijck, Jessica; Nijs, Jo; Meeus, Mira; Van Loo, Michel; Paul, Lorna
2012-03-01
A controlled experimental study was performed to examine the efficacy of the endogenous pain inhibitory systems and whether this (mal)functioning is associated with symptom increases following exercise in patients with chronic whiplash-associated disorders (WAD). In addition, 2 types of exercise were compared. Twenty-two women with chronic WAD and 22 healthy controls performed a submaximal and a self-paced, physiologically limited exercise test on a cycle ergometer with cardiorespiratory monitoring on 2 separate occasions. Pain pressure thresholds (PPT), health status, and activity levels were assessed in response to the 2 exercise bouts. In chronic WAD, PPT decreased following submaximal exercise, whereas they increased in healthy subjects. The same effect was established in response to the self-paced, physiologically limited exercise, with exception of the PPT at the calf which increased. A worsening of the chronic WAD symptom complex was reported post-exercise. Fewer symptoms were reported in response to the self-paced, physiologically limited exercise. These observations suggest abnormal central pain processing during exercise in patients with chronic WAD. Submaximal exercise triggers post-exertional malaise, while a self-paced and physiologically limited exercise will trigger less severe symptoms, and therefore seems more appropriate for chronic WAD patients. The results from this exercise study suggest impaired endogenous pain inhibition during exercise in people with chronic WAD. This finding highlights the fact that one should be cautious when evaluating and recommending exercise in people with chronic WAD, and that the use of more individual, targeted exercise therapies is recommended. Copyright © 2012 American Pain Society. Published by Elsevier Inc. All rights reserved.
Wegner, Alexander; Elsenbruch, Sigrid; Rebernik, Laura; Roderigo, Till; Engelbrecht, Elisa; Jäger, Marcus; Engler, Harald; Schedlowski, Manfred; Benson, Sven
2015-01-01
Abstract A role of the innate immune system is increasingly recognized as a mechanism contributing to pain sensitization. Experimental administration of the bacterial endotoxin lipopolysaccharide (LPS) constitutes a model to study inflammation-induced pain sensitization, but all existing human evidence comes from male participants. We assessed visceral and musculoskeletal pain sensitivity after low-dose LPS administration in healthy men and women to test the hypothesis that women show greater LPS-induced hyperalgesia compared with men. In this randomized, double-blind, placebo-controlled crossover study, healthy men (n = 20) and healthy women using oral contraceptives (n = 20) received an intravenous injection of 0.4 ng/kg body weight LPS or placebo. Pain sensitivity was assessed with established visceral and musculoskeletal pain models (ie, rectal pain thresholds; pressure pain thresholds for different muscle groups), together with a heartbeat perception (interoceptive accuracy) task. Plasma cytokines (tumor necrosis factor-α and interleukin-6) were measured along with state anxiety at baseline and up to 6-hour postinjection. Lipopolysaccharide application led to significant increases in plasma cytokines and state anxiety and decreased interoceptive awareness in men and women (P < 0.001, condition effects), with more pronounced LPS-induced cytokine increases in women (P < 0.05, interaction effects). Although both rectal and pressure pain thresholds were significantly decreased in the LPS condition (all P < 0.05, condition effect), no sex differences in endotoxin-induced sensitization were observed. In summary, LPS-induced systemic immune activation leads to visceral and musculoskeletal hyperalgesia, irrespective of biological sex. These findings support the broad applicability of experimental endotoxin administration as a translational preclinical model of inflammation-induced pain sensitization in both sexes. PMID:26058036
Filippopulos, Filipp M; Grafenstein, Jessica; Straube, Andreas; Eggert, Thomas
2015-11-01
In natural life pain automatically draws attention towards the painful body part suggesting that it interacts with different attentional mechanisms such as visual attention. Complex regional pain syndrome (CRPS) patients who typically report on chronic distally located pain of one extremity may suffer from so-called neglect-like symptoms, which have also been linked to attentional mechanisms. The purpose of the study was to further evaluate how continuous pain conditions influence visual attention. Saccade latencies were recorded in two experiments using a common visual attention paradigm whereby orientating saccades to cued or uncued lateral visual targets had to be performed. In the first experiment saccade latencies of healthy subjects were measured under two conditions: one in which continuous experimental pain stimulation was applied to the index finger to imitate a continuous pain situation, and one without pain stimulation. In the second experiment saccade latencies of patients suffering from CRPS were compared to controls. The results showed that neither the continuous experimental pain stimulation during the experiment nor the chronic pain in CRPS led to an unilateral increase of saccade latencies or to a unilateral increase of the cue effect on latency. The results show that unilateral, continuously applied pain stimuli or chronic pain have no or only very limited influence on visual attention. Differently from patients with visual neglect, patients with CRPS did not show strong side asymmetries of saccade latencies or of cue effects on saccade latencies. Thus, neglect-like clinical symptoms of CRPS patients do not involve the allocation of visual attention.
Hirsh, Adam T; George, Steven Z; Bialosky, Joel E; Robinson, Michael E
2008-09-01
Pain-related fear and catastrophizing are important variables of consideration in an individual's pain experience. Methodological limitations of previous studies limit strong conclusions regarding these relationships. In this follow-up study, we examined the relationships between fear of pain, pain catastrophizing, and experimental pain perception. One hundred healthy volunteers completed the Fear of Pain Questionnaire (FPQ-III), Pain Catastrophizing Scale (PCS), and Coping Strategies Questionnaire-Catastrophizing scale (CSQ-CAT) before undergoing the cold pressor test (CPT). The CSQ-CAT and PCS were completed again after the CPT, with participants instructed to complete these measures based on their experience during the procedure. Measures of pain threshold, tolerance, and intensity were collected and served as dependent variables in separate regression models. Sex, pain catastrophizing, and pain-related fear were included as predictor variables. Results of regression analyses indicated that after controlling for sex, pain-related fear was a consistently stronger predictor of pain in comparison to catastrophizing. These results were consistent when separate measures (CSQ-CAT vs PCS) and time points (pretask vs "in vivo") of catastrophizing were used. These findings largely corroborate those from our previous study and are suggestive of the absolute and relative importance of pain-related fear in the experimental pain experience. Although pain-related fear has received less attention in the experimental literature than pain catastrophizing, results of the current study are consistent with clinical reports highlighting this variable as an important aspect of the experience of pain.
Pain empathy in schizophrenia: an fMRI study.
Horan, William P; Jimenez, Amy M; Lee, Junghee; Wynn, Jonathan K; Eisenberger, Naomi I; Green, Michael F
2016-05-01
Although it has been proposed that schizophrenia is characterized by impaired empathy, several recent studies found intact neural responses on tasks measuring the affective subdomain of empathy. This study further examined affective empathy in 21 schizophrenia outpatients and 21 healthy controls using a validated pain empathy paradigm with two components: (i) observing videos of people described as medical patients who were receiving a painful sound stimulation treatment; (ii) listening to the painful sounds (to create regions of interest). The observing videos component incorporated experimental manipulations of perspective taking (instructions to imagine 'Self' vs 'Other' experiencing pain) and cognitive appraisal (information about whether treatment was 'Effective' vs 'Not Effective'). When considering activation across experimental conditions, both groups showed similar dorsal anterior cingulate cortex (dACC) and anterior insula (AI) activation while merely observing others in pain. However, there were group differences associated with perspective taking: controls showed relatively greater dACC and AI activation for the Self vs Other contrast whereas patients showed relatively greater activation in these and additional regions for the Other vs Self contrast. Although patients demonstrated grossly intact neural activity while observing others in pain, they showed more subtle abnormalities when required to toggle between imagining themselves vs others experiencing pain. © The Author (2016). Published by Oxford University Press. For Permissions, please email: journals.permissions@oup.com.
Koppenhaver, Shane L; Walker, Michael J; Rettig, Charles; Davis, Joel; Nelson, Chenae; Su, Jonathan; Fernández-de-Las-Peñas, Cesar; Hebert, Jeffrey J
2017-06-01
To investigate the relationship between dry needling-induced twitch response and change in pain, disability, nociceptive sensitivity, and lumbar multifidus muscle function, in patients with low back pain (LBP). Quasi-experimental study. Department of Defense Academic Institution. Sixty-six patients with mechanical LBP (38 men, 28 women, age: 41.3 [9.2] years). Dry needling treatment to the lumbar multifidus muscles between L3 and L5 bilaterally. Examination procedures included numeric pain rating, the Modified Oswestry Disability Index, pressure algometry, and real-time ultrasound imaging assessment of lumbar multifidus muscle function before and after dry needling treatment. Pain pressure threshold (PPT) was used to measure nocioceptive sensitivity. The percent change in muscle thickness from rest to contraction was calculated to represent muscle function. Participants were dichotomized and compared based on whether or not they experienced at least one twitch response on the most painful side and spinal level during dry needling. Participants experiencing local twitch response during dry needling exhibited greater immediate improvement in lumbar multifidus muscle function than participants who did not experience a twitch (thickness change with twitch: 12.4 [6]%, thickness change without twitch: 5.7 [11]%, mean difference adjusted for baseline value, 95%CI: 4.4 [1 to 8]%). However, this difference was not present after 1-week, and there were no between-groups differences in disability, pain intensity, or nociceptive sensitivity. The twitch response during dry needling might be clinically relevant, but should not be considered necessary for successful treatment. Published by Elsevier Ltd.
Cheing, G L; Hui-Chan, C W
1999-03-01
To investigate to what extent a single 60-minute session of transcutaneous electrical nerve stimulation (TENS) would modify chronic clinical pain, acute experimental pain, and the flexion reflex evoked in chronic low back pain patients. Thirty young subjects with chronic low back pain were randomly allocated to two groups, receiving either TENS or placebo stimulation to the lumbosacral region for 60 minutes. The flexion reflex was elicited by an electrical stimulation applied to the subject's right sole and recorded electromyographically from the biceps femoris and the tibialis anterior muscles. Subjective sensation of low back pain and the electrically induced pain were measured by two separate visual analog scales, termed VAS(LBP) and VAS(FR), respectively. Data obtained before, during, and 60 minutes after TENS and placebo stimulations were analyzed using repeated measures ANOVA. The VAS(LBP) score was significantly reduced to 63.1% of the prestimulation value after TENS (p<.001), but the reduction was negligible after placebo stimulation (to 96.7%, p = .786). In contrast, no significant change was found in the VASFR score (p = .666) and the flexion reflex area (p = .062) during and after stimulation within each group and between the two groups (p = .133 for VASFR and p = .215 for flexion reflex area). The same TENS protocol had different degrees of antinociceptive influence on chronic and acute pain in chronic low back pain patients.
Vaegter, Henrik B; Graven-Nielsen, Thomas
2016-07-01
Pain biomarkers are warranted for individualized pain management. Based on different pain modulatory phenotypes, the objectives of this study were to explore the existence of subgroups within patients with nonmalignant chronic pain and to investigate differences in clinical pain and pain hypersensitivity between subgroups. Cuff algometry was performed on lower legs in 400 patients with chronic pain to assess pressure pain threshold, pressure pain tolerance, temporal summation of pain (TSP: increase in pain scores to 10 repeated stimulations), and conditioned pain modulation (CPM: increase in cuff pressure pain threshold during cuff pain conditioning on the contralateral leg). Heat detection and heat pain thresholds at clinical painful and nonpainful body areas were assessed. Based on TSP and CPM, 4 distinct groups were formed: group 1 (n = 85) had impaired CPM and facilitated TSP; group 2 (n = 148) had impaired CPM and normal TSP; group 3 (n = 45) had normal CPM and facilitated TSP; and group 4 (n = 122) had normal CPM and normal TSP. Group 1 showed more pain regions than the other 3 groups (P < 0.001), indicating that impaired CPM and facilitated TSP play an important role in widespread pain. Groups 1 and 2 compared with group 4 had lower heat pain threshold at nonpainful areas and lower cuff pressure pain tolerance (P < 0.02), indicating that CPM plays a role for widespread hyperalgesia. Moreover, group 1 demonstrated higher clinical pain scores than group 4 (P < 0.05). Although not different between subgroups, patients were profiled on demographics, disability, pain catastrophizing, and fear of movement. Future research should investigate interventions tailored towards these subgroups.
Emotional modulation of experimental pain: a source imaging study of laser evoked potentials
Stancak, Andrej; Fallon, Nicholas
2013-01-01
Negative emotions have been shown to augment experimental pain. As induced emotions alter brain activity, it is not clear whether pain augmentation during noxious stimulation would be related to neural activation existing prior to onset of a noxious stimulus or alternatively, whether emotional stimuli would only alter neural activity during the period of nociceptive processing. We analyzed the spatio-temporal patterns of laser evoked potentials (LEPs) occurring prior to and during the period of cortical processing of noxious laser stimuli during passive viewing of negative, positive, or neutral emotional pictures. Independent component analysis (ICA) was applied to series of source activation volumes, reconstructed using local autoregressive average model (LAURA). Pain was the strongest when laser stimuli were associated with negative emotional pictures. Prior to laser stimulus and during the first 100 ms after onset of laser stimulus, activations were seen in the left and right medial temporal cortex, cerebellum, posterior cingulate, and rostral cingulate/prefrontal cortex. In all these regions, positive or neutral pictures showed stronger activations than negative pictures. During laser stimulation, activations in the right and left anterior insula, temporal cortex and right anterior and posterior parietal cortex were stronger during negative than neutral or positive emotional pictures. Results suggest that negative emotional stimuli increase activation in the left and right anterior insula and temporal cortex, and right posterior and anterior parietal cortex only during the period of nociceptive processing. The role of background brain activation in emotional modulation of pain appears to be only permissive, and consisting in attenuation of activation in structures maintaining the resting state of the brain. PMID:24062659
Kinesthetic illusions attenuate experimental muscle pain, as do muscle and cutaneous stimulation.
Gay, André; Aimonetti, Jean-Marc; Roll, Jean-Pierre; Ribot-Ciscar, Edith
2015-07-30
In the present study, muscle pain was induced experimentally in healthy subjects by administrating hypertonic saline injections into the tibialis anterior (TA) muscle. We first aimed at comparing the analgesic effects of mechanical vibration applied to either cutaneous or muscle receptors of the TA or to both types simultaneously. Secondly, pain alleviation was compared in subjects in whom muscle tendon vibration evoked kinesthetic illusions of the ankle joint. Muscle tendon vibration, which primarily activated muscle receptors, reduced pain intensity by 30% (p<0.01). In addition, tangential skin vibration reduced pain intensity by 33% (p<0.01), primarily by activating cutaneous receptors. Concurrently stimulating both sensory channels induced stronger analgesic effects (-51%, p<0.01), as shown by the lower levels of electrodermal activity. The strongest analgesic effects of the vibration-induced muscle inputs occurred when illusory movements were perceived (-38%, p=0.01). The results suggest that both cutaneous and muscle sensory feedback reduce muscle pain, most likely via segmental and supraspinal processes. Further clinical trials are needed to investigate these new methods of muscle pain relief. Copyright © 2015 Elsevier B.V. All rights reserved.
Torta, D M; Legrain, V; Mouraux, A; Valentini, E
2017-04-01
Several studies have used neuroimaging techniques to investigate brain correlates of the attentional modulation of pain. Although these studies have advanced the knowledge in the field, important confounding factors such as imprecise theoretical definitions of attention, incomplete operationalization of the construct under exam, and limitations of techniques relying on measuring regional changes in cerebral blood flow have hampered the potential relevance of the conclusions. Here, we first provide an overview of the major theories of attention and of attention in the study of pain to bridge theory and experimental results. We conclude that load and motivational/affective theories are particularly relevant to study the attentional modulation of pain and should be carefully integrated in functional neuroimaging studies. Then, we summarize previous findings and discuss the possible neural correlates of the attentional modulation of pain. We discuss whether classical functional neuroimaging techniques are suitable to measure the effect of a fluctuating process like attention, and in which circumstances functional neuroimaging can be reliably used to measure the attentional modulation of pain. Finally, we argue that the analysis of brain networks and spontaneous oscillations may be a crucial future development in the study of attentional modulation of pain, and why the interplay between attention and pain, as examined so far, may rely on neural mechanisms shared with other sensory modalities. Copyright © 2017 Elsevier Ltd. All rights reserved.
de Bruijn, Saskia T; van Wijck, Albert J M; Geenen, Rinie; Snijders, Tom J; van der Meulen, Wout J T M; Jacobs, Johannes W G; Veldhuijzen, Dieuwke Swaantje
2011-09-01
It has been suggested that low physical fitness is a contributor to pain in fibromyalgia and that exercise-related beliefs play a role in the persistence of this association. Yet the association between physical fitness and pain is hardly explored in detail. The aim of this exploratory study in patients with fibromyalgia was to investigate the association of physical fitness levels with self-reported and experimental pain as well as with pain catastrophizing and activity-avoidance beliefs. Physical fitness of 18 patients with fibromyalgia was examined using maximal ergocycling and the 6-minute walking test (6MWT). Pain intensity was assessed using self-report scales and quantitative sensory testing. A reduced walking distance on the 6MWT was correlated with more severe self-reported pain on the Fibromyalgia Impact Questionnaire (r = -0.52, P < 0.05). Recovery of heart rate after ergocycling was correlated with cold pain thresholds (r = 0.70, P < 0.01), pressure pain thresholds (r = -0.70, P < 0.01), and heat wind-up (r = 0.66, P < 0.05). Activity-avoidance beliefs correlated with a lower peak VO2 on the cycle test (r = -0.52, P < 0.05), a shorter distance on the 6MWT (r = -0.56, P < 0.05), and more severe self-reported pain (r = 0.61, P < 0.05), reflecting that patients with activity-avoidance beliefs were less physically fit and experienced more severe pain. The results demonstrate some associations between physical fitness and pain in fibromyalgia and point to the importance of activity avoidance. Although the causal directionality of the associations needs substantiation in clinical research, the findings support the notion that low fitness and activity-avoidance beliefs should be targeted while treating pain in fibromyalgia.
Park, Jihong; Denning, W Matt; Pitt, Jordan D; Francom, Devin; Hopkins, J Ty; Seeley, Matthew K
2017-01-01
Although knee pain is common, some facets of this pain are unclear. The independent effects (ie, independent from other knee injury or pathology) of knee pain on neural activation of lower-extremity muscles during landing and jumping have not been observed. To investigate the independent effects of knee pain on lower-extremity muscle (gastrocnemius, vastus medialis, medial hamstrings, gluteus medius, and gluteus maximus) activation amplitude during landing and jumping, performed at 2 different intensities. Laboratory-based, pretest, posttest, repeated-measures design, where all subjects performed both data-collection sessions. Thirteen able-bodied subjects performed 2 different land and jump tasks (forward and lateral) under 2 different conditions (control and pain), at 2 different intensities (high and low). For the pain condition, experimental knee pain was induced via a hypertonic saline injection into the right infrapatellar fat pad. Functional linear models were used to evaluate the influence of experimental knee pain on muscle-activation amplitude throughout the 2 land and jump tasks. Experimental knee pain independently altered activation for all of the observed muscles during various parts of the 2 different land and jump tasks. These activation alterations were not consistently influenced by task intensity. Experimental knee pain alters activation amplitude of various lower-extremity muscles during landing and jumping. The nature of the alteration varies between muscles, intensities, and phases of the movement (ie, landing and jumping). Generally, experimental knee pain inhibits the gastrocnemius, medial hamstring, and gluteus medius during landing while independently increasing activation of the same muscles during jumping.
Analgesics as Reinforcers with Chronic Pain: Evidence from Operant Studies
Ewan, Eric E.; Martin, Thomas J.
2013-01-01
Previously preclinical pain research has focused on simple behavioral endpoints to assess the efficacy of analgesics in acute and chronic pain models, primarily reflexive withdrawal from an applied mechanical or thermal stimulus. However recent research has been aimed at investigating other behavioral states in the presence of pain, including spontaneous, non-elicited pain. One approach is to investigate the reinforcing effects of analgesics in animals with experimental pain, which should serve as reinforcers by virtue of their ability to alleviate the relevant subjective states induced by pain. The gold standard for assessing drug reinforcement is generally accepted to be drug self-administration, and this review highlights the ability of drugs to serve as reinforcers in animals with experimental neuropathic pain, and the extent to which this behavior is altered in chronic pain states. Additionally, intracranial self-stimulation is an operant procedure that has been used extensively to study drug reinforcement mechanisms and the manner in which neuropathic pain alters the ability of drugs to serve as reinforcers in this paradigm will also be discussed. Drug self-administration and intracranial self-stimulation have promise as tools to investigate behavioral effects of analgesics in animals with chronic pain, particularly regarding the mechanisms through which these drugs motivate consumption in a chronic pain state. PMID:23973302
Immediate effects of spinal manipulation on thermal pain sensitivity: an experimental study
George, Steven Z; Bishop, Mark D; Bialosky, Joel E; Zeppieri, Giorgio; Robinson, Michael E
2006-01-01
Background The underlying causes of spinal manipulation hypoalgesia are largely unknown. The beneficial clinical effects were originally theorized to be due to biomechanical changes, but recent research has suggested spinal manipulation may have a direct neurophysiological effect on pain perception through dorsal horn inhibition. This study added to this literature by investigating whether spinal manipulation hypoalgesia was: a) local to anatomical areas innervated by the lumbar spine; b) correlated with psychological variables; c) greater than hypoalgesia from physical activity; and d) different for A-delta and C-fiber mediated pain perception. Methods Asymptomatic subjects (n = 60) completed baseline psychological questionnaires and underwent thermal quantitative sensory testing for A-delta and C-fiber mediated pain perception. Subjects were then randomized to ride a stationary bicycle, perform lumbar extension exercise, or receive spinal manipulation. Quantitative sensory testing was repeated 5 minutes after the intervention period. Data were analyzed with repeated measures ANOVA and post-hoc testing was performed with Bonferroni correction, as appropriate. Results Subjects in the three intervention groups did not differ on baseline characteristics. Hypoalgesia from spinal manipulation was observed in lumbar innervated areas, but not control (cervical innervated) areas. Hypoalgesic response was not strongly correlated with psychological variables. Spinal manipulation hypoalgesia for A-delta fiber mediated pain perception did not differ from stationary bicycle and lumbar extension (p > 0.05). Spinal manipulation hypoalgesia for C-fiber mediated pain perception was greater than stationary bicycle riding (p = 0.040), but not for lumbar extension (p = 0.105). Conclusion Local dorsal horn mediated inhibition of C-fiber input is a potential hypoalgesic mechanism of spinal manipulation for asymptomatic subjects, but further study is required to replicate this finding
Madeleine, Pascal; Mathiassen, Svend Erik; Arendt-Nielsen, Lars
2008-03-01
The aim of the present study was to investigate the effect of experimental and chronic neck-shoulder pain on the magnitude of cycle-to-cycle variability of task timing, kinematics and muscle activation during repetitive arm movement performed for 3 or 5 min. In an experimental part, acute muscle pain was induced in healthy subjects by intramuscular injection of hypertonic saline in trapezius (n = 10) and infraspinatus (n = 10) muscles. In a clinical part, workers with (n = 12) and without (n = 6) chronic neck-shoulder pain were compared. Cycle-to-cycle standard deviations of task duration, arm and trunk movement in 3D and surface electromyographic (EMG) root mean square activity were computed to assess the degree of variability. The variability in task timing increased in presence of both experimental and chronic pain (P < 0.05) compared with non-painful conditions. Experimental pain increased the variability of the starting position of the arm (P < 0.05), the arm range of motion (P < 0.01), the arm and trunk movement area (P < 0.01) and the acceleration of the arm (P < 0.01). In the chronic pain condition, the variability of arm and trunk acceleration (P < 0.01) and EMG activity (P < 0.05) was decreased compared with healthy controls. These results indicate that pain alters the magnitude of motor variability, and that the transition from acute to chronic pain is accompanied by changes in motor patterns. Experimental pain likely resulted in a quest for a motor solution reducing nociceptive influx, while chronic pain was characterised by a diminished motor flexibility.
Sørensen, T J; Langberg, H; Hodges, P W; Bliddal, H; Henriksen, M
2012-01-01
Knee joint pain and reduced quadriceps strength are cardinal symptoms in many knee pathologies. In people with painful knee pathologies, quadriceps exercise reduces pain, improves physical function, and increases muscle strength. A general assumption is that pain compromises muscle function and thus may prevent effective rehabilitation. This study evaluated the effects of experimental knee joint pain during quadriceps strength training on muscle strength gain in healthy individuals. Twenty-seven healthy untrained volunteers participated in a randomized controlled trial of quadriceps strengthening (3 times per week for 8 weeks). Participants were randomized to perform resistance training either during pain induced by injections of painful hypertonic saline (pain group, n = 13) or during a nonpainful control condition with injection of isotonic saline (control group, n = 14) into the infrapatellar fat pad. The primary outcome measure was change in maximal isokinetic muscle strength in knee extension/flexion (60, 120, and 180 degrees/second). The group who exercised with pain had a significantly larger improvement in isokinetic muscle strength at all angular velocities of knee extension compared to the control group. In knee flexion there were improvements in isokinetic muscle strength in both groups with no between-group differences. Experimental knee joint pain improved the training-induced gain in muscle strength following 8 weeks of quadriceps training. It remains to be studied whether knee joint pain has a positive effect on strength gain in patients with knee pathology. Copyright © 2012 by the American College of Rheumatology.
Duration of Analgesia Induced by Acupuncture-Like TENS on Experimental Heat Pain.
Tousignant-Laflamme, Yannick; Brochu, Marilyne; Dupuis-Michaud, Cynthia; Pagé, Catherine; Popovic, Draga; Simard, Marie-Eve
2013-01-01
Background. Acupuncture-like TENS (AL-TENS) is a treatment modality that can be used to temporarily reduce pain. However, there is no clear data in the literature regarding the specific duration of analgesia induced by AL-TENS. Objectives. To describe and quantify the duration and magnitude of AL-TENS analgesia on experimental heat pain in healthy subjects and verify if the duration or magnitude of analgesia induced by the AL-TENS was influenced by the duration of the application of the AL-TENS (15 versus 30 minutes). Methods. A repeated-measures, intrasubject randomized experimental design was used, where each participant was his/her own control. 22 healthy volunteers underwent heat pain stimulations with a contact thermode before (pretest) and after (posttest) AL-TENS application (15 and 30 minutes). Outcome measures included subjective pain during AL-TENS, duration, and magnitude of AL-TENS-induced analgesia. Results. Survival analysis showed that the median duration of AL-TENS analgesia was 10 minutes following the application of either 15 or 30 minutes of AL-TENS. The magnitude of analgesia following either application was comparable at all points in time (P values > 0.05) and ranged between -20% and -36% pain reduction. Conclusion. Only half of the participants still had heat-pain analgesia induced by the AL-TENS at 15 minutes postapplication.
Freimann, Tiina; Merisalu, Eda; Pääsuke, Mati
2015-01-01
Cervical and lumbar range of motion limitations are usually associated with musculoskeletal pain in the neck and lower back, and are a major health problem among nurses. Physical exercise has been evaluated as an effective intervention method for improving cervical and lumbar range of motion, and for preventing and reducing musculoskeletal pain. The purpose of this study was to investigate the effects of a home-exercise therapy programme on cervical and lumbar range of motion among intensive care unit nurses who had experienced mild to moderate musculoskeletal pain in the neck and or lower back during the previous six months. A quasi-experimental study was conducted among intensive care unit nurses at Tartu University Hospital (Estonia) between May and July 2011. Thirteen nurses who had suffered musculoskeletal pain episodes in the neck and or lower back during the previous six months underwent an 8-week home-exercise therapy programme. Eleven nurses without musculoskeletal pain formed a control group. Questions from the Nordic Musculoskeletal Questionnaire and the 11-point Visual Analogue Scale were used to select potential participants for the experimental group via an assessment of the prevalence and intensity of musculoskeletal pain. Cervical range of motion and lumbar range of motion in flexion, extension, lateral flexion and (cervical range of motion only) rotation were measured with a digital goniometer. A paired t-test was used to compare the measured parameters before and after the home-exercise therapy programme. A Student's t-test was used to analyse any differences between the experimental and control groups. After the home-exercise therapy, there was a significant increase (p < 0.05) in cervical range of motion in flexion, extension, lateral flexion and rotation, and in lumbar range of motion in lateral flexion. Cervical range of motion in flexion was significantly higher (p < 0.01) in the experimental group compared to the control group after
van Selm, M J; Gibson, W I; Travers, M J; Moseley, G L; Hince, D; Wand, B M
2018-04-20
Visualizing one's own painful body part appears to have an effect on reported pain intensity. Furthermore, it seems that manipulating the size of the viewed image can determine the direction and extent of this phenomenon. When visual distortion has been applied to clinical populations, the analgesic effects have been in opposition to those observed in some experimental pain models. To help resolve this problem, we explored the effect of visualisation and magnification of the visual image on reported pain using a delayed onset muscle soreness (DOMS) pain model. We induced DOMS in the quadriceps of 20 healthy volunteers. Forty-eight hours later, participants performed a series of painful contractions of the DOMS-affected muscle under four randomised conditions: (1) Viewing the injured thigh; (2) Viewing the contralateral thigh; (3) Viewing a neutral object; and (4) Viewing the injured thigh through magnifying glasses. For each condition, participants rated their pain intensity during a series of painful contractions. We observed that direct visualisation of the injured thigh had no effect on pain intensity when compared to viewing the contralateral thigh or neutral object. However, magnification of the DOMS-affected leg during the performance of painful contractions caused participants to report more pain than when viewing the injured thigh normally. These results further demonstrate that the effect of visualisation varies between different pain conditions. These results may have implications for the integration of visual feedback into clinical practice. We present delayed onset muscle soreness as a model for exploring visually induced analgesia. Our findings suggest that this phenomenon is expressed differently in exogenous and endogenous experimental pain models. Further exploration may offer a potential pathway for the integration of visual analgesia into the management of clinical pain. © 2018 European Pain Federation - EFIC®.
Yang, Jin-Hyang
2009-02-01
The purpose of this study was to identify the effects of hand acupuncture therapy on pain, ROM, ADL, and depression among older people with low back pain and knee joint pain. The research was a quasi-experimental design using a non-equivalent control group pre-post test. The participants were 40 patients, 18 in the experimental group and 22 in the control group. A pretest and 2 posttest were conducted to measure the main variables. For the experimental group, hand acupuncture therapy, consisting of hand acupuncture and press-pellets based on corresponding points, was given. There were statistically significant differences in pain, ROM in knee joint, and ADL in the experimental group but not in depression compared to the control group over two different times. The hand acupuncture therapy was effective for low back pain, knee joint pain, ROM in knee joint and ADL among the elders in this study. Therefore, the hand acupuncture therapy can be utilized in the field of geriatric nursing as a nursing intervention for older people with low back pain and knee joint pain.
Shan, Di; He, Yuwei; Long, Hu; Zhou, Yang; Liu, He; Xu, Rui; Huang, Renhuan; Lai, Wenli
2016-11-01
The aim of this study was to determine the effects of nociceptin/orphanin FQ peptide receptor (N/OFQ receptor) antagonist on orofacial pain induced by experimental tooth movement in rats. A total of 36 male Sprague-Dawley rats weighing 200-300 g were divided into six groups: a control group, force group, force+saline intraperitoneal group, force+saline periodontal group, force+UFP-101 ([Nphe¹,Arg¹⁴,Lys¹⁵]N/OFQ-NH ₂ antagonist for N/OFQ receptor) intraperitoneal group, and force+UFP-1 01 periodontal group. Closed coil springs were ligated between the upper incisors and first molar to exert an orthodontic force (40 g) between the teeth. Injectable administration dosages were 30 μl saline or 30 μl saline containing 0.03 mg/kg UFP-1 01. Following the injections, orofacial pain levels were assessed through directed face grooming (mouth wiping). Statistical analyses were performed in SPSS 17.0 (Statistical Package for the Social Sciences) and p values less than 0.05 were considered as statistically significant. Orofacial pain levels were significantly higher in the force group than in the control group. Orofacial pain levels differed significantly between the force)group, force+saline periodontal group and force+UFP-101 periodontal group, but were similar between the control group, force+UFP-101 intraperitoneal group and force+saline intraperitoneal group. Moreover, orofacial pain levels did not differ between the force group, force+saline intraperitoneal group and force+UFP-1 01 intraperitoneal group. Periodontal, but not intraperitoneal, administration of UFP-101 could alleviate orofacial pain induced by experimental tooth movement in rats, suggesting that periodontal N/OFQ receptors participate in orofacial pain induced by experimental tooth movement.
Chan, Joanne C Y; Hamamura, Takeshi
2015-08-01
Pain management is a priority in nursing care but little is known about the factors that affect nursing students' assessment of pain expressed by patients of different ethnic backgrounds. This study examined undergraduate nursing students' assessment of pain and decision of triage when pain was expressed in different languages and their relation to students' empathy and social identity. Comparison between students with and without clinical experience was also carried out. This is a cross-sectional quantitative design. This study took place at a university in Hong Kong. 74 female undergraduate nursing students. Students listened to eight audio recordings in which an individual expressed pain in one of the two dialects of Chinese, either Cantonese or Putonghua. For each dialect, two recordings depicted mild pain and two depicted severe pain. After listening to each recording, students rated the pain level and indicated their decision of triage. Subsequently, students completed a questionnaire that measured their empathy and social identity and reported their demographics. The data were analyzed by descriptive statistics, correlational analyses, and t-tests. Severe pain described in Putonghua was rated as more intense than that described in Cantonese but it was not classified as more urgent. Students with clinical experience tended to perceive mild pain as less painful and less urgent than those without clinical experience. For mild pain described in Cantonese, students with clinical experience evaluated it as more urgent than those without such experience. The empathy level of students with and without clinical experience was comparable. Students with more empathy, especially those without clinical experience, reported heightened perceived intensity of severe pain described in Putonghua. Nurse educators should note that empathy, social identity, and clinical experience may alter students' pain assessment of patients from different ethnicities. Pain education needs to
Breimhorst, Markus; Sandrock, Stephan; Fechir, Marcel; Hausenblas, Nadine; Geber, Christian; Birklein, Frank
2011-01-01
The present study addresses the question whether pain-intensity ratings and skin conductance responses (SCRs) are able to detect different intensities of phasic painful stimuli and to determine the reliability of this discrimination. For this purpose, 42 healthy participants of both genders were assigned to either electrical, mechanical, or laser heat-pain stimulation (each n = 14). A whole range of single brief painful stimuli were delivered on the right volar forearm of the dominant hand in a randomized order. Pain-intensity ratings and SCRs were analyzed. Using generalizability theory, individual and gender differences were the main contributors to the variability of both intensity ratings and SCRs. Most importantly, we showed that pain-intensity ratings are a reliable measure for the discrimination of different pain stimulus intensities in the applied modalities. The reliability of SCR was adequate when mechanical and heat stimuli were tested but failed for the discrimination of electrical stimuli. Further studies are needed to reveal the reason for this lack of accuracy for SCRs when applying electrical pain stimuli. Our study could help researchers to better understand the relationship between pain and activation of the sympathetic nervous system. Pain researchers are furthermore encouraged to consider individual and gender differences when measuring pain intensity and the concomitant SCRs in experimental settings. Copyright © 2011 American Pain Society. Published by Elsevier Inc. All rights reserved.
Yosipovitch, Gil; Meredith, Gregory; Chan, Yiong Huak; Goh, Chee Leok
2004-02-01
The perception of pain is a personal experience influenced by many factors, including genetic, ethnic and cultural issues. Understanding these perceptions is especially important in dermatologic patients undergoing minor surgical operations and who often differ in their pain response to surgical treatments. Little is known about how these differences affect the perception of experimental pain. The purpose of this study was to determine experimental pain perception differences in three distinct East Asian ethnic populations. Pain thresholds were examined with a psychophysical computerized quantitative thermal sensory testing device (TSA 2001) in healthy volunteers recruited from three different Asian ethnic groups. Using the methods of limits, experimental pain perception threshold was measured on the forehead and volar aspect of the forearm in 49 healthy subjects. The measurements were then repeated after skin barrier perturbation with adhesive tape stripping of the stratum corneum. All three ethnic groups were analyzed separately with respect to age, gender educational level and skin type. A total of 20 Chinese, 14 Malay and 15 Indian subjects completed the study. Thermal pain thresholds were similar in all three ethnic groups before and after tape strippings. No significant differences were noted between genders. Using quantitative sensory thermal testing, we demonstrated that no significant differences in pain occur between different races and genders.
Lai, Chien-Hung; Leung, Ting-Kai; Peng, Chih-Wei; Chang, Kwang-Hwa; Lai, Ming-Jun; Lai, Wen-Fu; Chen, Shih-Ching
2014-02-01
The objective of this study was to determine the relative efficacy of irradiation using a device containing a far-infrared emitting ceramic powder (cFIR) for the management of chronic myofascial neck pain compared with a control treatment. This was a randomized, double-blind, placebo-controlled pilot study. The study comprised 48 patients with chronic, myofascial neck pain. Patients were randomly assigned to the experimental group or the control (sham-treatment) group. The patients in the experimental group wore a cFIR neck device for 1 week, and the control group wore an inert neck device for 1 week. Quantitative measurements based on a visual analogue scale (VAS) scoring of pain, a sleep quality assessment, pressure-pain threshold (PPT) testing, muscle tone and compliance analysis, and skin temperature analysis were obtained. Both the experimental and control groups demonstrated significant improvement in pain scores. However, no statistically significant difference in the pain scores was observed between the experimental and control groups. Significant decreases in muscle stiffness in the upper regions of the trapezius muscles were reported in the experimental group after 1 week of treatment. Short-term treatment using the cFIR neck device partly reduced muscle stiffness. Although the differences in the VAS and PPT scores for the experimental and control groups were not statistically significant, the improvement in muscle stiffness in the experimental group warrants further investigation of the long-term effects of cFIR treatment for pain management.
Moont, Ruth; Crispel, Yonatan; Lev, Rina; Pud, Dorit; Yarnitsky, David
2012-01-30
Methods to cognitively distract subjects from pain and experimental paradigms to induce conditioned pain modulation (CPM; formerly termed diffuse noxious inhibitory controls or DNIC) have each highlighted activity changes in closely overlapping cortical areas. This is the first study, to our knowledge, to compare cortical activation changes during these 2 manipulations in the same experimental set-up. Our study sample included thirty healthy young right handed males capable of expressing CPM. We investigated brief consecutive time windows using 32-channel EEG-based sLORETA, to determine dynamic changes in localized cortical potentials evoked by phasic noxious heat stimuli to the left volar forearm. This was performed under visual cognitive distraction tasks and conditioning hot-water pain to the right hand (CPM), both individually and simultaneously. Previously we have shown that for CPM, there is increased activity in frontal cortical regions followed by reduced activation of the somatosensory areas, suggesting a pain inhibitory role for these frontal regions. We now observed that distraction caused a different extent of cortical activation; greater early activation of frontal areas (DLPFC, OFC and caudal ACC at 250-350 ms post-stimulus), yet lesser reduction in the somatosensory cortices, ACC, PCC and SMA after 350 ms post-stimulus, compared to CPM. Both CPM and distraction reduced subjective pain scores to a similar extent. Combining CPM and distraction further reduced pain ratings compared to CPM and distraction alone, supporting the dissimilarity of the mechanisms of pain modulation under these 2 manipulations. The results are discussed in terms of the differential functional roles of the prefrontal cortex. Copyright © 2011 Elsevier B.V. All rights reserved.
IL17 Mediates Pelvic Pain in Experimental Autoimmune Prostatitis (EAP)
Murphy, Stephen F.; Schaeffer, Anthony J.; Done, Joseph; Wong, Larry; Bell-Cohn, Ashlee; Roman, Kenny; Cashy, John; Ohlhausen, Michelle; Thumbikat, Praveen
2015-01-01
Chronic pelvic pain syndrome (CPPS) is the most common form of prostatitis, accounting for 90–95% of all diagnoses. It is a complex multi-symptom syndrome with unknown etiology and limited effective treatments. Previous investigations highlight roles for inflammatory mediators in disease progression by correlating levels of cytokines and chemokines with patient reported symptom scores. It is hypothesized that alteration of adaptive immune mechanisms results in autoimmunity and subsequent development of pain. Mouse models of CPPS have been developed to delineate these immune mechanisms driving pain in humans. Using the experimental autoimmune prostatitis (EAP) in C57BL/6 mice model of CPPS we examined the role of CD4+T-cell subsets in the development and maintenance of prostate pain, by tactile allodynia behavioral testing and flow cytometry. In tandem with increased CD4+IL17A+ T-cells upon EAP induction, prophylactic treatment with an anti-IL17 antibody one-day prior to EAP induction prevented the onset of pelvic pain. Therapeutic blockade of IL17 did not reverse pain symptoms indicating that IL17 is essential for development but not maintenance of chronic pain in EAP. Furthermore we identified a cytokine, IL7, to be associated with increased symptom severity in CPPS patients and is increased in patient prostatic secretions and the prostates of EAP mice. IL7 is fundamental to development of IL17 producing cells and plays a role in maturation of auto-reactive T-cells, it is also associated with autoimmune disorders including multiple sclerosis and type-1 diabetes. More recently a growing body of research has pointed to IL17’s role in development of neuropathic and chronic pain. This report presents novel data on the role of CD4+IL17+ T-cells in development and maintenance of pain in EAP and CPPS. PMID:25933188
IL17 Mediates Pelvic Pain in Experimental Autoimmune Prostatitis (EAP).
Murphy, Stephen F; Schaeffer, Anthony J; Done, Joseph; Wong, Larry; Bell-Cohn, Ashlee; Roman, Kenny; Cashy, John; Ohlhausen, Michelle; Thumbikat, Praveen
2015-01-01
Chronic pelvic pain syndrome (CPPS) is the most common form of prostatitis, accounting for 90-95% of all diagnoses. It is a complex multi-symptom syndrome with unknown etiology and limited effective treatments. Previous investigations highlight roles for inflammatory mediators in disease progression by correlating levels of cytokines and chemokines with patient reported symptom scores. It is hypothesized that alteration of adaptive immune mechanisms results in autoimmunity and subsequent development of pain. Mouse models of CPPS have been developed to delineate these immune mechanisms driving pain in humans. Using the experimental autoimmune prostatitis (EAP) in C57BL/6 mice model of CPPS we examined the role of CD4+T-cell subsets in the development and maintenance of prostate pain, by tactile allodynia behavioral testing and flow cytometry. In tandem with increased CD4+IL17A+ T-cells upon EAP induction, prophylactic treatment with an anti-IL17 antibody one-day prior to EAP induction prevented the onset of pelvic pain. Therapeutic blockade of IL17 did not reverse pain symptoms indicating that IL17 is essential for development but not maintenance of chronic pain in EAP. Furthermore we identified a cytokine, IL7, to be associated with increased symptom severity in CPPS patients and is increased in patient prostatic secretions and the prostates of EAP mice. IL7 is fundamental to development of IL17 producing cells and plays a role in maturation of auto-reactive T-cells, it is also associated with autoimmune disorders including multiple sclerosis and type-1 diabetes. More recently a growing body of research has pointed to IL17's role in development of neuropathic and chronic pain. This report presents novel data on the role of CD4+IL17+ T-cells in development and maintenance of pain in EAP and CPPS.
Graven-Nielsen, T; Svensson, P; Arendt-Nielsen, L
1997-04-01
The relation between muscle pain, muscle activity, and muscle co-ordination is still controversial. The present human study investigates the influence of experimental muscle pain on resting, static, and dynamic muscle activity. In the resting and static experiments, the electromyography (EMG) activity and the contraction force of m. tibialis anterior were assessed before and after injection of 0.5 ml hypertonic saline (5%) into the same muscle. In the dynamic experiment, injections of 0.5 ml hypertonic saline (5%) were performed into either m. tibialis anterior (TA) or m. gastrocnemius (GA) and the muscle activity and co-ordination were investigated during gait on a treadmill by EMG recordings from m. TA and m. GA. At rest no evidence of EMG hyperactivity was found during muscle pain. The maximal voluntary contraction (MVC) during muscle pain was significantly lower than the control condition (P < 0.05). During a static contraction at 80% of the pre-pain MVC muscle pain caused a significant reduction in endurance time (P < 0.043). During dynamic contractions, muscle pain resulted in a significant decrease of the EMG activity in the muscle, agonistic to the painful muscle (P < 0.05), and a significant increase of the EMG activity of the muscle, antagonistic to the painful muscle (P < 0.05). Muscle pain seems to cause a general protection of painful muscles during both static and dynamic contractions. The increased EMG activity of the muscle antagonistic to the painful muscle is probably a functional adaptation of muscle co-ordination in order to limit movements. Modulation of muscle activity by muscle pain could be controlled via inhibition of muscles agonistic to the movement and/or excitation of muscles antagonistic to the movement. The present results are in accordance with the pain-adaptation model (Lund, J.P., Stohler, C.S. and Widmer, C.G. In: H. Vaerøy and H. Merskey (Eds.), Progress in Fibromyalgia and Myofascial Pain. Elsevier, Amsterdam, 1993, pp. 311
Younger, Jarred; Aron, Arthur; Parke, Sara; Chatterjee, Neil; Mackey, Sean
2010-10-13
The early stages of a new romantic relationship are characterized by intense feelings of euphoria, well-being, and preoccupation with the romantic partner. Neuroimaging research has linked those feelings to activation of reward systems in the human brain. The results of those studies may be relevant to pain management in humans, as basic animal research has shown that pharmacologic activation of reward systems can substantially reduce pain. Indeed, viewing pictures of a romantic partner was recently demonstrated to reduce experimental thermal pain. We hypothesized that pain relief evoked by viewing pictures of a romantic partner would be associated with neural activations in reward-processing centers. In this functional magnetic resonance imaging (fMRI) study, we examined fifteen individuals in the first nine months of a new, romantic relationship. Participants completed three tasks under periods of moderate and high thermal pain: 1) viewing pictures of their romantic partner, 2) viewing pictures of an equally attractive and familiar acquaintance, and 3) a word-association distraction task previously demonstrated to reduce pain. The partner and distraction tasks both significantly reduced self-reported pain, although only the partner task was associated with activation of reward systems. Greater analgesia while viewing pictures of a romantic partner was associated with increased activity in several reward-processing regions, including the caudate head, nucleus accumbens, lateral orbitofrontal cortex, amygdala, and dorsolateral prefrontal cortex--regions not associated with distraction-induced analgesia. The results suggest that the activation of neural reward systems via non-pharmacologic means can reduce the experience of pain.
Geschwind, Nicole; Meulders, Michel; Peters, Madelon L; Vlaeyen, Johan W S; Meulders, Ann
2015-03-01
Recent experimental data show that associative learning processes are involved not only in the acquisition but also in the spreading of pain-related fear. Clinical studies suggest involvement of positive affect in resilience against chronic pain. Surprisingly, the role of positive affect in associative learning in general, and in fear generalization in particular, has received scant attention. In a voluntary movement paradigm, in which one arm movement (reinforced conditioned stimulus [CS+]) was followed by a painful stimulus and another was not (unreinforced conditioned stimulus [CS-]), we tested generalization of fear inhibition in response to 5 novel but related generalization movements (GSs; within-subjects) after either a positive affect induction or a control exercise (Group = between-subjects) in healthy participants (N = 50). The GSs' similarity with the original CS+ movement and CS- movement varied. Fear learning was assessed via verbal ratings. Results indicated that there was an interaction between the increase in positive affect and the linear generalization gradient. Stronger increases in positive affect were associated with steeper generalization curves because of relatively lower pain-unconditioned stimulus expectancy and less fear of stimuli more similar to the CS-. There was no Group by Stimulus interaction. Results thus suggest that positive affect may enhance safety learning through promoting generalization from known safe movements to novel yet related movements. Improved safety learning may be a central mechanism underlying the association between positive affect and increased resilience against chronic pain. We investigated the extent to which positive affect influences the generalization (ie, spreading) of pain-related fear inhibition in response to situations similar to the original, pain-eliciting situation. Results suggest that increasing positive affect in the acute pain stage may limit the spreading of pain-related fear, thereby
Lee, Jennifer E.; Watson, David; Frey-Law, Laura A.
2012-01-01
Background Recent studies suggest an underlying three- or four-factor structure explains the conceptual overlap and distinctiveness of several negative emotionality and pain-related constructs. However, the validity of these latent factors for predicting pain has not been examined. Methods A cohort of 189 (99F; 90M) healthy volunteers completed eight self-report negative emotionality and pain-related measures (Eysenck Personality Questionnaire-Revised; Positive and Negative Affect Schedule; State-Trait Anxiety Inventory; Pain Catastrophizing Scale; Fear of Pain Questionnaire; Somatosensory Amplification Scale; Anxiety Sensitivity Index; Whiteley Index). Using principal axis factoring, three primary latent factors were extracted: General Distress; Catastrophic Thinking; and Pain-Related Fear. Using these factors, individuals clustered into three subgroups of high, moderate, and low negative emotionality responses. Experimental pain was induced via intramuscular acidic infusion into the anterior tibialis muscle, producing local (infusion site) and/or referred (anterior ankle) pain and hyperalgesia. Results Pain outcomes differed between clusters (multivariate analysis of variance and multinomial regression), with individuals in the highest negative emotionality cluster reporting the greatest local pain (p = 0.05), mechanical hyperalgesia (pressure pain thresholds; p = 0.009) and greater odds (2.21 OR) of experiencing referred pain compared to the lowest negative emotionality cluster. Conclusion Our results provide support for three latent psychological factors explaining the majority of the variance between several pain-related psychological measures, and that individuals in the high negative emotionality subgroup are at increased risk for (1) acute local muscle pain; (2) local hyperalgesia; and (3) referred pain using a standardized nociceptive input. PMID:23165778
Roman, Kenny; Done, Joseph D.; Schaeffer, Anthony J.; Murphy, Stephen F.; Thumbikat, Praveen
2014-01-01
Chronic prostatitis/Chronic pelvic pain syndrome (CP/CPPS) affects up to 15% of the male population and is characterized by pelvic pain. Mast cells are implicated in the murine experimental autoimmune prostatitis (EAP) model as key to chronic pelvic pain development. The mast cell mediator tryptase-β and its cognate receptor protease-activated receptor 2 (PAR2) are involved in mediating pain in other visceral disease models. Prostatic secretions and urines from CP/CPPS patients were examined for the presence of mast cell degranulation products. Tryptase-β and PAR2 expression were examined in murine experimental autoimmune prostatitis (EAP). Pelvic pain and inflammation were assessed in the presence or absence of PAR2 expression and upon PAR2 neutralization. Tryptase-β and carboxypeptidase A3 were elevated in CP/CPPS compared to healthy volunteers. Tryptase-β was capable of inducing pelvic pain and was increased in EAP along with its receptor PAR2. PAR2 was required for the development of chronic pelvic pain in EAP. PAR2 signaling in dorsal root ganglia lead to ERK1/2 phosphorylation and calcium influx. PAR2 neutralization using antibodies attenuated chronic pelvic pain in EAP. The tryptase-PAR2 axis is an important mediator of pelvic pain in EAP and may play a role in the pathogenesis of CP/CPPS. PMID:24726923
The effect of electroacupuncture and tramadol on experimental tourniquet pain.
Musial, Frauke; Choi, Kyung-Eun; Gabriel, Tim; Lüdtke, Rainer; Rampp, Thomas; Michalsen, Andreas; Dobos, Gustav
2012-03-01
The hypoalgesic effect of electroacupuncture (EA) was directly compared with the analgesic effect of pharmacological interventions using the submaximum effort tourniquet technique (SETT). 125 healthy subjects (mean age 24.44±4.46 years; 62.4% female, 37.6% male) performed SETT at baseline and under one of five experimental conditions (n=25 per group): EA (2 Hz with burst pulses in alternating one-phase-square wave pulses; burst length 180 μs, burst frequency 80 Hz, stimulation time/pulse width 3 s), tramadol (50 mg), ibuprofen (400 mg), placebo pill or non-treatment control. EA was performed at LI4 and LI10 contralaterally with stimulation beginning 20 min before SETT and lasting throughout SETT. The pharmacological interventions were given in a double-blind design 1 h before the SETT assessment. Subjects showed a hypoalgesic effect of the opiate and of the EA for subjective pain rating (EA p=0.0051; tramadol p=0.0299), and pain tolerance index (time/rating) (EA p=0.043; tramadol p=0.047) analysed using analysis of covariance. More subjects reached the strict time limit of 30 min (analysed by logistic regression and adjusted OR as a post-hoc analysis) under EA compared with most other experimental conditions. Only EA and tramadol were not significantly different (95% Wald confidence limits: non-treatment control vs EA 0.011 to 0.542; placebo pill vs EA 0.009 to 0.438; ibuprofen vs EA 0.021 to 0.766; tramadol vs EA 0.065 to 1.436). In a laboratory setting, an EA procedure was as effective as a single dose of an orally administered opiate in reducing experimentally induced ischaemic pain.
Avellán, Nina-Li; Sorsa, Timo; Tervahartiala, Taina; Forster, Clemens; Kemppainen, Pentti
2008-02-01
Tooth pain can induce a neurogenic inflammatory reaction in gingiva in association with local elevations of matrix metalloproteinase (MMP)-8, which is considered the major tissue destructive protease in gingival crevice fluid (GCF). The pro-inflammatory neuropeptides released by sensory nerves coordinate the activities of the immuno-effector cells and may influence the secretion of MMP-8. With this background, we studied whether experimental tooth pain can trigger changes in GCF levels of the neuropeptide substance P (SP) and MMP-8. The GCF SP levels of stimulated and non-stimulated teeth were analyzed for SP using a competitive enzyme immunoassay (EIA). The GCF MMP-8 levels were determined by quantitative immunofluorometric assay (IFMA). Painful stimulation of the upper central incisor caused significant elevations in GCF SP and MMP-8 levels of the stimulated tooth. At the same time, the GCF SP and MMP-8 levels of non-stimulated control teeth were unchanged. These data indicate that experimental tooth pain can induce local elevations of SP and MMP-8 levels in GCF simultaneously. This supports the possibility of a local neurogenic spread of inflammatory reactions from intrapulpal to surrounding periodontal tissues.
Nir, Rony-Reuven; Granovsky, Yelena; Yarnitsky, David; Sprecher, Elliot; Granot, Michal
2011-05-01
Endogenous analgesia (EA) can be examined experimentally using a conditioned pain modulation (CPM) paradigm. While noxious conditioning stimulation intensities (CSIs) are mainly used, it has not been fully investigated in the same experimental design whether the experienced conditioning pain level affects CPM responses. The principal goal of the present study was to characterize CPM induction and magnitudes evoked by various conditioning pain levels. Furthermore, we explored associations between conditioning pain reports and CPM responses across various CSIs. Thirty healthy, young, right-handed males were tested with a parallel CPM paradigm. Three different CSIs (hand water-immersion) induced mild, moderate and intense pain levels, rated 12.41 ± 7.85, 31.57 ± 9.56 and 58.1 ± 11.43, respectively (0-100 numerical pain scale) (P < 0.0001). Contact-heat 'test-stimulus' levels were compared before and during conditioning. Within the group, (i) CPM was induced only by the moderate and intense CSIs (Ps ≤ 0.001); (ii) no difference was demonstrated between the magnitudes of these CPM responses. Regression analysis revealed that CPM induction was independent of the perceived conditioning pain level, but associated with the absolute CSI (P < 0.0001). Conditioning pain levels were correlated across all CSIs, as were CPM magnitudes (Ps ≤ 0.01). We conclude that among males, (i) once a CPM response is evoked by a required conditioning pain experience, its magnitude is not further affected by increasing conditioning pain and (ii) CPM magnitudes are inter-correlated, but unrelated to conditioning pain reports. These observations may suggest that CPM responses represent an intrinsic element of an individual's EA processes, which are not significantly affected by the experienced conditioning pain. Copyright © 2010 European Federation of International Association for the Study of Pain Chapters. Published by Elsevier Ltd. All rights reserved.
Analgesic effect of clobazam in chronic low-back pain but not in experimentally induced pain.
Schliessbach, J; Vuilleumier, P H; Siegenthaler, A; Bütikofer, L; Limacher, A; Juni, P; Zeilhofer, H U; Arendt-Nielsen, L; Curatolo, M
2017-09-01
Chronic pain is frequently associated with hypersensitivity of the nervous system, and drugs that increase central inhibition are therefore a potentially effective treatment. Benzodiazepines are potent modulators of GABAergic neurotransmission and are known to exert antihyperalgesic effects in rodents, but translation into patients are lacking. This study investigates the effect of the benzodiazepine clobazam in chronic low-back pain in humans. The aim of this study is to explore the effect of GABA modulation on chronic low-back pain and on quantitative sensory tests. In this double-blind cross-over study, 49 patients with chronic low-back pain received a single oral dose of clobazam 20 mg or active placebo tolterodine 1 mg. Pain intensity on the 0-10 numeric rating scale and quantitative sensory tests were assessed during 2 h after drug intake. Pain intensity in the supine position was significantly reduced by clobazam compared to active placebo (60 min: 2.9 vs. 3.5, p = 0.008; 90 min: 2.7 vs. 3.3, p = 0.024; 120 min: 2.4 vs. 3.1, p = 0.005). Pain intensity in the sitting position was not significantly different between groups. No effects on quantitative sensory tests were observed. This study suggests that clobazam has an analgesic effect in patients with chronic low-back pain. Muscle relaxation or sedation may have contributed to the effect. Development of substances devoid of these side effects would offer the potential to further investigate the antihyperalgesic action of GABAergic compounds. Modulation of GABAergic pain-inhibitory pathways may be a potential future therapeutic target. © 2017 European Pain Federation - EFIC®.
Tse, Mimi Mun Yee; Yeung, Suey Shuk Yu; Lee, Paul Hong; Ng, Shamay Sheung Mei
2016-09-01
OBJECTIVES : To examine the feasibility of a peer-led pain management program among nursing home residents. DESIGN : A quasi-experimental design. SETTING : Two nursing homes. SUBJECTS : Fifty nursing home residents. METHODS : The experimental group (n = 32) was given a 12-week group-based peer-led pain management program. There were two 1-hour sessions per week. Education in pain and demonstrations of nonpharmacological pain management strategies were provided. The research team and 12 trained peers led the sessions. The control group (n = 18) received one 1-hour session of pain management program each week over 12 weeks from the research team only. Outcome measures for the participants were collected at baseline (P1) and at week 12 (P2). Data from peer volunteers were collected prior to training (V1) and at week 12 (V2). T-tests were used to compare the differences in outcome measures collected at two time points. RESULTS : There was a significant reduction in pain intensity from 5.8 ± 2.6 (P1) to 3.4 ± 2.5 (P2) for the experimental group (p = 0.003) and from 6.3 ± 3.0 (P1) to 3.1 ± 2.4 (P2) for the control group (p = 0.001). Activities of daily living significantly improved for both the experimental group (p = 0.008) and the control group (p = 0.014). There was an enhancement in happiness level for the experimental group (p < 0.001), while the loneliness level dropped significantly for the experimental group (p < 0.001) and the control group (p = 0.031). The peer volunteers showed a significant increase in self-rated pain management knowledge (2.9 ± 2.6 to 8.1 ± 1.2, p < 0.001) and self-efficacy in volunteering (5.8 ± 2.9 to 8.3 ± 1.5, p = 0.032). CONCLUSION : The peer-led pain management program was feasible and has potential in relieving chronic pain and enhancing the physical and psychological health of nursing home residents. © 2016 American Academy of Pain
Claydon, Leica S; Chesterton, Linda S; Barlas, Panos; Sim, Julius
2011-09-01
To determine the hypoalgesic effects of transcutaneous electrical nerve stimulation (TENS) parameter combinations on experimental models in healthy humans. Searches were performed using the electronic databases Ovid MEDLINE, CINAHL, AMED, and Web of Science (from inception to December 2009). Manual searches of journals and reference lists of retrieved trials were also performed. Randomized controlled trials (RCTs) were included in the review if they compared the hypoalgesic effect of TENS relative with placebo and control, using an experimental pain model in healthy human participants. Two reviewers independently selected the trials, assessed their methodologic quality and extracted data. Forty-three RCTs were eligible for inclusion. A best evidence synthesis revealed: Overall "conflicting" (inconsistent findings in multiple RCTs) evidence of TENS efficacy on experimental pain irrespective of TENS parameters used. Overall intense TENS has "moderate" evidence of efficacy (1 high-quality and 2 low-quality trials). Conventional TENS has overall conflicting evidence of efficacy, this is derived from "strong" evidence of efficacy (generally consistent findings in multiple high-quality RCTs) on pressure pain but strong evidence of inefficacy on other pain models. "Limited" evidence (positive findings from 1 RCT) of hypoalgesia exists for some novel parameters. Low-intensity, low-frequency, local TENS has strong evidence of inefficacy. Inappropriate TENS (using "barely perceptible" intensities) has moderate evidence of inefficacy. The level of hypoalgesic efficacy of TENS is clearly dependent on TENS parameter combination selection (defined in terms of intensity, frequency, and stimulation site) and experimental pain model. Future clinical RCTs may consider these TENS dose responses.
Edwards, Rhiannon; Eccleston, Christopher; Keogh, Edmund
2017-05-01
Despite the well-documented sex and gender differences, little is known about the relative impact of male-female social interactions on pain. Three experiments were conducted to investigate whether the type of interpersonal relationship men and women have with an observer affects how they respond to experimental pain. Study 1 recruited friends and strangers, study 2 examined the effects of same- and opposite-sex friends, whereas study 3 investigated the differences between opposite-sex friends and opposite-sex romantic partners. One hundred forty-four dyads were recruited (48 in each study). One person from each dyad completed 2 pain tasks, whereas the other person observed in silence. Overall, the presence of another person resulted in an increase in pain threshold and tolerance on the cold-pressor task and algometer. The sex status of the dyads also had a role, but only within the friendship groups. In particular, male friends had the most pronounced effect on men's pain, increasing pain tolerance. We suggest that the presence of an observer, their sex, and the nature of the participant-observer relationship all influence how pain is reported. Further research should focus on dyadic relationships, and their influence on how men and women report and communicate pain in specific contexts.
Pilot study of a novel pain management strategy: evaluating the impact on patient outcomes.
Keller, D S; Tahilramani, R N; Flores-Gonzalez, J R; Ibarra, S; Haas, E M
2016-06-01
experimental cohort. With the favorable finding from the pilot study, further investigation is warranted to fully evaluate the impact of this pain management protocol on patient satisfaction, clinical and financial outcomes.
Motrich, Ruben D; Breser, María L; Sánchez, Leonardo R; Godoy, Gloria J; Prinz, Immo; Rivero, Virginia E
2016-03-01
Pain and inflammation in the absence of infection are hallmarks in chronic prostatitis and chronic pelvic pain syndrome (CP/CPPS) patients. The etiology of CP/CPPS is unclear, and autoimmunity has been proposed as a cause. Experimental autoimmune prostatitis (EAP) models have long been used for studying CP/CPPS. Herein, we studied prostate inflammation induction and chronic pelvic pain development in EAP using IL-12p40-KO, IL-4-KO, IL-17-KO, and wild-type (C57BL/6) mice. Prostate antigen (PAg) immunization in C57BL/6 mice induced specific Th1 and Th17 immune responses and severe prostate inflammation and cell infiltration, mainly composed of CD4 T cells and macrophages. Moreover, chronic pelvic pain was evidenced by increased allodynia responses. In immunized IL-17-KO mice, the presence of a prominent PAg-specific Th1 immune response caused similar prostate inflammation and chronic pelvic pain. Furthermore, markedly high PAg-specific Th1 immune responses, exacerbated prostate inflammation, and chronic pelvic pain were detected in immunized IL-4-KO mice. Conversely, immunized IL-12p40-KO mice developed PAg-specific Th2 immune responses, characterized by high IL-4 secretion and neither infiltration nor damage in the prostate. As observed in wild-type control animals, IL12p40-KO mice did not evidence tactile allodynia responses. Our results suggest that, as in patients, chronic pelvic pain is a consequence of prostate inflammation. After PAg immunization, a Th1-associated immune response develops and induces prostate inflammation and chronic pelvic pain. The absence of Th1 or Th2 cytokines, respectively, diminishes or enhances EAP susceptibility. In addition, IL-17 showed not to be essential for pathology induction and chronic pelvic pain development.
Positive Traits Linked to Less Pain through Lower Pain Catastrophizing
Hood, Anna; Pulvers, Kim; Carrillo, Janet; Merchant, Gina; Thomas, Marie
2011-01-01
The present study examined the association between positive traits, pain catastrophizing, and pain perceptions. We hypothesized that pain catastrophizing would mediate the relationship between positive traits and pain. First, participants (n = 114) completed the Trait Hope Scale, the Life Orientation Test- Revised, and the Pain Catastrophizing Scale. Participants then completed the experimental pain stimulus, a cold pressor task, by submerging their hand in a circulating water bath (0º Celsius) for as long as tolerable. Immediately following the task, participants completed the Short-Form McGill Pain Questionnaire (MPQ-SF). Pearson correlation found associations between hope and pain catastrophizing (r = −.41, p < .01) and MPQ-SF scores (r = −.20, p < .05). Optimism was significantly associated with pain catastrophizing (r = −.44, p < .01) and MPQ-SF scores (r = −.19, p < .05). Bootstrapping, a non-parametric resampling procedure, tested for mediation and supported our hypothesis that pain catastrophizing mediated the relationship between positive traits and MPQ-SF pain report. To our knowledge, this investigation is the first to establish that the protective link between positive traits and experimental pain operates through lower pain catastrophizing. PMID:22199416
Altering gender role expectations: effects on pain tolerance, pain threshold, and pain ratings.
Robinson, Michael E; Gagnon, Christine M; Riley, Joseph L; Price, Donald D
2003-06-01
The literature demonstrating sex differences in pain is sizable. Most explanations for these differences have focused on biologic mechanisms, and only a few studies have examined social learning. The purpose of this study was to examine the contribution of gender-role stereotypes to sex differences in pain. This study used experimental manipulation of gender-role expectations for men and women. One hundred twenty students participated in the cold pressor task. Before the pain task, participants were given 1 of 3 instructional sets: no expectation, 30-second performance expectation, or a 90-second performance expectation. Pain ratings, threshold, and tolerance were recorded. Significant sex differences in the "no expectation" condition for pain tolerance (t = 2.32, df = 38, P <.05) and post-cold pressor pain ratings (t = 2.6, df = 37, P <.05) were found. Women had briefer tolerance times and higher post-cold pressor ratings than men. When given gender-specific tolerance expectations, men and women did not differ in their pain tolerance, pain threshold, or pain ratings. This is the first empirical study to show that manipulation of expectations alters sex differences in laboratory pain.
Goodin, Burel R.; Quinn, Noel B.; Kronfli, Tarek; King, Christopher D.; Page, Gayle G.; Haythornthwaite, Jennifer A.; Edwards, Robert R.; Stapleton, Laura M.; McGuire, Lynanne
2011-01-01
Objective Current evidence supports the efficacy of hypnosis for reducing the pain associated with experimental stimulation and various acute and chronic conditions; however, the mechanisms explaining how hypnosis exerts its effects remain less clear. The hypothalamic-pituitary-adrenal (HPA) axis and pro-inflammatory cytokines represent potential targets for investigation given their purported roles in the perpetuation of painful conditions; yet, no clinical trials have thus far examined the influence of hypnosis on these mechanisms. Design Healthy participants, highly susceptible to the effects of hypnosis, were randomized to either a hypnosis intervention or a no-intervention control. Using a cold pressor task, assessments of pain intensity and pain unpleasantness were collected prior to the intervention (Pre) and following the intervention (Post) along with pain-provoked changes in salivary cortisol and the soluble receptor of tumor necrosis factor-α (sTNFαRII). Results Compared to the no-intervention control, data analyses revealed that hypnosis significantly reduced pain intensity and pain unpleasantness. Hypnosis was not significantly associated with suppression of cortisol or sTNFαRII reactivity to acute pain from Pre to Post; however, the effect sizes for these associations were medium-sized. Conclusions Overall, the findings from this randomized controlled pilot study support the importance of a future large-scale study on the effects of hypnosis for modulating pain-related changes of the HPA axis and pro-inflammatory cytokines. PMID:22233394
Koppitz, Andrea; Bosshard, Georg; Blanc, Geneviève; Hediger, Hannele; Payne, Sheila; Volken, Thomas
2017-04-21
It is estimated that 19 to 83% of people with dementia suffer from pain that is inadequately treated in the last months of life. A large number of healthcare workers who care for these people in nursing homes lack appropriate expertise and may therefore not always recognise, assess and treat pain in those with dementia who have complex problems on time, properly and efficiently. The aim of this intervention trial is to identify care needs of people with dementia suffering from pain living in a nursing home. A quasi-experimental nurse-led intervention trial based on a convenience sample of four nursing homes in the Swiss Canton of Zurich examines the effects on dementia patients (n = 411), the healthcare institution and the qualification level of the healthcare workers compared to historical controls, using an event analysis and a multilevel analysis. Healthcare workers will be individually trained how to assess, intervene and evaluate acute and chronic pain. There are three data-monitoring cycles (T0, T1, T2) and two intervention cycles (I1, I2) with a total study duration of 425 days. There is also a process evaluation based on Dobbins analyses that analyse in particular the potentials for change in clinical practice of change agents. The aim of the intervention trial is to improve pain management strategies in older people with dementia in nursing homes. Clinically significant findings will be expected that will help reduce suffering in the sense of "total pain" for people with dementia. The joint intra- and interdisciplinary collaboration between practice and supply-oriented (nursing) research will have both a lasting effect on the efficiency measurement and provide scientifically sound results. Nursing homes can integrate the findings from the intervention trial into their internal quality control process. The potential for improvements can be directly influenced by the nursing home itself. Registration trial number: DRKS00009726 on DRKS, registered 10
Do fibromyalgia patients benefit from cognitive restructuring and acceptance? An experimental study.
Kohl, Annika; Rief, Winfried; Glombiewski, Julia Anna
2014-12-01
The aim of this study was to clarify mechanisms of psychological fibromyalgia treatment by experimentally examining the effectiveness of its core elements. We assessed the effects of cognitive restructuring and acceptance on experimentally-induced heat and cold pain tolerance and pain intensity in fibromyalgia patients. Cold and heat pain were induced in a sample of 60 fibromyalgia patients using a thermode. We conducted ANCOVAs to examine group differences in posttest scores, co-varying for pretest scores. The between-groups factor was the type of instruction provided (acceptance, cognitive restructuring, and a control condition). In addition, we controlled for pain sensitivity, age, and depression. We found that acceptance and cognitive restructuring were superior to the control condition in increasing heat pain tolerance, but did not differ from one another. With respect to cold pain tolerance, cognitive restructuring was associated with increases in cold pain tolerance compared to the control condition, while acceptance did not differ either from the control condition or from cognitive restructuring. Further experimental research on chronic pain treatment mechanisms is needed, particularly research on individually tailoring treatment strategies according to patients characteristics. Results show that both, cognitive restructuring and acceptance instructions, enhance pain tolerance in fibromyalgia patients. Copyright © 2014 Elsevier Ltd. All rights reserved.
Pain management for older persons living in nursing homes: a pilot study.
Tse, Mimi M Y; Ho, Suki S K
2013-06-01
Because the prevalence of chronic pain among the elderly in nursing homes is high and decreases their quality of life, effective nonpharmacologic pain management should be promoted. The purpose of this quasiexperimental pretest and posttest control design was to enhance pain management in nursing homes via an integrated pain management program (IPMP) for staff and residents. Nursing staff and residents from the experimental nursing home were invited to join the 8-week IPMP, whereas staff and residents from the control nursing home did not receive the IPMP. Baseline data were collected from nursing staff and residents in both groups before and after the IPMP. The IPMP consisted of eight lectures on pain assessment, drug knowledge,and nondrug strategies for the nursing staff, and 8 weeks of activities, including gardening therapy and physiotherapy exercise, for the residents. There were 48 and 42 older people in the experimental and control groups, respectively. No significant differences were found in their educational level, sleep quality, bowel habits, past and present health conditions, pain conditions and psychologic well-being parameters (p > .05) at baseline. After the IPMP, the experimental nursing staff showed a significant improvement in their knowledge of and attitudes to pain management (p < .05), and the experimental residents reported significantly lower pain scores and used more nondrug strategies for pain relief compared with the control group (p < .05). Moreover, the psychologic well-being parameters, including happiness, loneliness, life satisfaction, and geriatric depression, had significantly improved among the experimental residents (p < .05). The IPMP was effective in enhancing the knowledge and attitudes of nursing staff, as well as reducing pain conditions and enhancing psychologic well-being for older persons in nursing homes. Copyright © 2013 American Society for Pain Management Nursing. Published by Elsevier Inc. All rights reserved.
Effects of sleeping position on back pain in physically active seniors: A controlled pilot study.
Desouzart, Gustavo; Matos, Rui; Melo, Filipe; Filgueiras, Ernesto
2015-01-01
The increase in life expectancy of elderly population has aroused the interest of different knowledge areas in understanding the variables that are involved in the aging process, linking them to other concepts such as active aging, healthy aging and the bio-psycho-social changes. This paper presents the results of the first controlled, experimental pilot study that aimed to analyze the relationship between the perception of back pain and the sleeping position adopted by physically active female seniors. Twenty female seniors (mean age 62.70 ± 3.827) participated in this study. The individuals were separated in 2 groups (Experimental and Control Group). For the carrying out of this study, the Visual Analogue Scale (VAS) was used to measure the intensity of back pain in the spine before and after four consecutive weeks an Intervention program. Individuals in the Experimental Group were instructed regarding the recommended way to sleep position (Intervention program) according to the pathological problems or the amount of pain reported. The Experimental Group (N = 10) presented significantly (p = 0.009) fewer complaints of back pain after an Intervention program in comparison to individuals who did not receive this type of information (Control Group).
Yavuz, Utku Ş; Negro, Francesco; Falla, Deborah; Farina, Dario
2015-08-01
It has been observed that muscle pain influences force variability and low-frequency (<3 Hz) oscillations in the neural drive to muscle. In this study, we aimed to investigate the effect of experimental muscle pain on the neural control of muscle force at higher frequency bands, associated with afferent feedback (alpha band, 5-13 Hz) and with descending cortical input (beta band, 15-30 Hz). Single-motor unit activity was recorded, in two separate experimental sessions, from the abductor digiti minimi (ADM) and tibialis anterior (TA) muscles with intramuscular wire electrodes, during isometric abductions of the fifth finger at 10% of maximal force [maximum voluntary contraction (MVC)] and ankle dorsiflexions at 25% MVC. The contractions were repeated under three conditions: no pain (baseline) and after intramuscular injection of isotonic (0.9%, control) and hypertonic (5.8%, painful) saline. The results showed an increase of the relative power of both the force signal and the neural drive at the tremor frequency band (alpha, 5-13 Hz) between the baseline and hypertonic (painful) conditions for both muscles (P < 0.05) but no effect on the beta band. Additionally, the strength of motor unit coherence was lower (P < 0.05) in the hypertonic condition in the alpha band for both muscles and in the beta band for the ADM. These results indicate that experimental muscle pain increases the amplitude of the tremor oscillations because of an increased variability of the neural control (common synaptic input) in the tremor band. Moreover, the concomitant decrease in coherence suggests an increase in independent input in the tremor band due to pain. Copyright © 2015 the American Physiological Society.
Steen, K H; Reeh, P W; Kreysel, H W
1995-09-01
Topically applied acetylsalicylic acid (ASA), salicylic acid (SA) and indomethacin were tested in an experimental pain model that provides direct nociceptor excitation through cutaneous tissue acidosis. In 30 volunteers, sustained burning pain was produced in the palmar forearm through a continuous intradermal pressure infusion of a phosphate-buffered isotonic solution (pH 5.2). In 5 different, double-blind, randomized cross-over studies with 6 volunteers each, the flow rate of the syringe pump was individually adjusted to result in constant pain ratings of around 20% (50% in study 4) on a visual analog scale (VAS). The painful skin area was then covered with either placebo or the drugs which had been dissolved in diethylether. In the first study on 6 volunteers, ASA (60 mg/ml) or lactose (placebo) in diethylether (10 ml) was applied, using both arms at 3-day intervals. Both treatments resulted in sudden and profound pain relief due to the cooling effect of the evaporating ether. With lactose, however, the mean pain rating was restored close to the baseline within 6-8 min while, with ASA, it remained significantly depressed for the rest of the observation period (another 20 min). This deep analgesia was not accompanied by a loss of tactile sensation. The further studies served to show that indomethacin (4.5 mg/ml) and SA (60 mg/ml) were equally effective as ASA (each 92-96% pain reduction) and that the antinociceptive effects were due to local but not systemic actions, since ASA and SA dis not reach measurable plasma levels up to 3 h after topical applications. With a higher flow rate of acid buffer producing more intense pain (VAS 50%). ASA and SA were still able to significantly reduce the ratings by 90% or 84%, respectively. On the other hand, by increasing the flow rate by a factor of 2 on average, during the period of fully developed drug effect it was possible to overcome the pain suppression, which suggests a competitive mechanism of (acetyl-) salicylic
Vlaev, Ivo; Seymour, Ben; Chater, Nick; Winston, Joel S; Yoshida, Wako; Wright, Nicholas; Symmonds, Mkael; Dolan, Ray
2014-01-01
A standard view in health economics is that, although there is no market that determines the "prices" for health states, people can nonetheless associate health states with monetary values (or other scales, such as quality adjusted life year [QALYs] and disability adjusted life year [DALYs]). Such valuations can be used to shape health policy, and a major research challenge is to elicit such values from people; creating experimental "markets" for health states is a theoretically attractive way to address this. We explore the possibility that this framework may be fundamentally flawed-because there may not be any stable values to be revealed. Instead, perhaps people construct ad hoc values, influenced by contextual factors, such as the observed decisions of others. The participants bid to buy relief from equally painful electrical shocks to the leg and arm in an experimental health market based on an interactive second-price auction. Thirty subjects were randomly assigned to two experimental conditions where the bids by "others" were manipulated to follow increasing or decreasing price trends for one, but not the other, pain. After the auction, a preference test asked the participants to choose which pain they prefer to experience for a longer duration. Players remained indifferent between the two pain-types throughout the auction. However, their bids were differentially attracted toward what others bid for each pain, with overbidding during decreasing prices and underbidding during increasing prices. Health preferences are dissociated from market prices, which are strongly referenced to others' choices. This suggests that the price of health care in a free-market has the capacity to become critically detached from people's underlying preferences. 2014 APA, all rights reserved
Shiozawa, Shinichiro; Hirata, Rogerio Pessoto; Graven-Nielsen, Thomas
2015-01-01
Postural control during rapid movements may be impaired due to musculoskeletal pain. The purpose of this study was to investigate the effect of experimental knee-related muscle pain on the center of pressure (CoP) displacement in a reaction time task condition. Nine healthy males performed two reaction time tasks (dominant side shoulder flexion and bilateral heel lift) before, during, and after experimental pain induced in the dominant side vastus medialis or the tibialis anterior muscles by hypertonic saline injections. The CoP displacement was extracted from the ipsilateral and contralateral side by two force plates and the net CoP displacement was calculated. Compared with non-painful sessions, tibialis anterior muscle pain during the peak and peak-to-peak displacement for the CoP during anticipatory postural adjustments (APAs) of the shoulder task reduced the peak-to-peak displacement of the net CoP in the medial-lateral direction (P<0.05). Tibialis anterior and vastus medialis muscle pain during shoulder flexion task reduced the anterior-posterior peak-to-peak displacement in the ipsilateral side (P<0.05). The central nervous system in healthy individuals was sufficiently robust in maintaining the APA characteristics during pain, although the displacement of net and ipsilateral CoP in the medial-lateral and anterior-posterior directions during unilateral fast shoulder movement was altered.
ERIC Educational Resources Information Center
Alalo, Fadeelah Mansour Ahmed; Ahmad, Awatef El Sayed; El Sayed, Hoda Mohamed Nafee
2016-01-01
Venipuncture and other invasive procedures as blood draws, intramuscular injections or heel pricks are the most commonly performed painful procedures in children. These can be a terrifying and painful experience for children and their families. The present study aimed to identify Pain intensity after an ice pack application prior to venipuncture…
Del Casale, Antonio; Ferracuti, Stefano; Rapinesi, Chiara; De Rossi, Pietro; Angeletti, Gloria; Sani, Gabriele; Kotzalidis, Georgios D; Girardi, Paolo
2015-12-01
Several studies reported that hypnosis can modulate pain perception and tolerance by affecting cortical and subcortical activity in brain regions involved in these processes. We conducted an Activation Likelihood Estimation (ALE) meta-analysis on functional neuroimaging studies of pain perception under hypnosis to identify brain activation-deactivation patterns occurring during hypnotic suggestions aiming at pain reduction, including hypnotic analgesic, pleasant, or depersonalization suggestions (HASs). We searched the PubMed, Embase and PsycInfo databases; we included papers published in peer-reviewed journals dealing with functional neuroimaging and hypnosis-modulated pain perception. The ALE meta-analysis encompassed data from 75 healthy volunteers reported in 8 functional neuroimaging studies. HASs during experimentally-induced pain compared to control conditions correlated with significant activations of the right anterior cingulate cortex (Brodmann's Area [BA] 32), left superior frontal gyrus (BA 6), and right insula, and deactivation of right midline nuclei of the thalamus. HASs during experimental pain impact both cortical and subcortical brain activity. The anterior cingulate, left superior frontal, and right insular cortices activation increases could induce a thalamic deactivation (top-down inhibition), which may correlate with reductions in pain intensity. Copyright © 2016 Elsevier Ltd. All rights reserved.
Tang, Nicole K.Y.; Goodchild, Claire E.; Sanborn, Adam N.; Howard, Jonathan; Salkovskis, Paul M.
2012-01-01
Objectives: Because insomnia is a common comorbidity of chronic pain, scientific and clinical interest in the relationship of pain and sleep has surged in recent years. Although experimental studies suggest a sleep-interfering property of pain and a pain-enhancing effect of sleep deprivation/fragmentation, the temporal association between pain and sleep as experienced by patients is less understood. The current study was conducted to examine the influence of presleep pain on subsequent sleep and sleep on pain reports the next day, taking into consideration other related psychophysiologic variables such as mood and arousal. Design: A daily process study, involving participants to monitor their pain, sleep, mood, and presleep arousal for 1 wk. Multilevel modeling was used to analyze the data. Setting: In the patients' natural living and sleeping environment. Patients: One hundred nineteen patients (73.9% female, mean age = 46 years) with chronic pain and concomitant insomnia. Measurement: An electronic diary was used to record patients' self-reported sleep quality/efficiency and ratings of pain, mood, and arousal at different times of the day; actigraphy was also used to provide estimates of sleep efficiency. Results: Results indicated that presleep pain was not a reliable predictor of subsequent sleep. Instead, sleep was better predicted by presleep cognitive arousal. Although sleep quality was a consistent predictor of pain the next day, the pain-relieving effect of sleep was only evident during the first half of the day. Conclusions: These findings challenge the often-assumed reciprocal relationship between pain and sleep and call for a diversification in thinking of the daily interaction of these 2 processes. Citation: Tang NKY; Goodchild CE; Sanborn AN; Howard J; Salkovskis PM. Deciphering the temporal link between pain and sleep in a heterogeneous chronic pain patient sample: a multilevel daily process study. SLEEP 2012;35(5):675-687. PMID:22547894
Fu, Yu; Yu, Ge; McNichol, Elaine; Marczewski, Kathryn; José Closs, S
2016-07-01
Self-management may be a lifelong task for patients with chronic back pain. Research suggests that chronic pain self-management programmes have beneficial effects on patients' health outcome. Contemporary pain management theories and models also suggest that a good patient-professional partnership enhances patients' ability to self-manage their condition. (1) To investigate whether there is a reciprocal relationship between self-management of chronic back pain and health-related quality of life (HRQoL); (2) to examine the impact of a good patient-professional partnership on HRQoL, either directly, or indirectly via change in the ability to self-manage pain. This quasi-experimental study was designed to take place during routine service appointments and conducted in a community-based pain management service in the United Kingdom. A patient-professional partnership was established in which patients were actively involved in setting up goals and developing individualised care plans. Through this, health professionals undertook patients' health needs assessment, collaborated with patients to identify specific problems, provided written materials and delivered individualised exercise based on patients' life situation. Patients were recruited following initial consultation and followed up three months later. A total of 147 patients (65% female) with a mean age of 48 years (standard deviation (SD): 14 years) were enrolled in the study. Of these, 103 subjects completed the study. Patients were included if they were aged 18 and over, suffered from chronic back pain, had opted in to the clinic and had sufficient ability to read and understand English. Patients were excluded if they opted out this service after the initial assessment, suffered from malignant pain or required acute medical interventions for their pain relief. Self-reported measures of HRQoL, patient-professional partnerships and self-management ability were collected at baseline and three months later
Ge, Hong-You; Vangsgaard, Steffen; Omland, Øyvind; Madeleine, Pascal; Arendt-Nielsen, Lars
2014-12-06
Musculoskeletal pain from the upper extremity and shoulder region is commonly reported by computer users. However, the functional status of central pain mechanisms, i.e., central sensitization and conditioned pain modulation (CPM), has not been investigated in this population. The aim was to evaluate sensitization and CPM in computer users with and without chronic musculoskeletal pain. Pressure pain threshold (PPT) mapping in the neck-shoulder (15 points) and the elbow (12 points) was assessed together with PPT measurement at mid-point in the tibialis anterior (TA) muscle among 47 computer users with chronic pain in the upper extremity and/or neck-shoulder pain (pain group) and 17 pain-free computer users (control group). Induced pain intensities and profiles over time were recorded using a 0-10 cm electronic visual analogue scale (VAS) in response to different levels of pressure stimuli on the forearm with a new technique of dynamic pressure algometry. The efficiency of CPM was assessed using cuff-induced pain as conditioning pain stimulus and PPT at TA as test stimulus. The demographics, job seniority and number of working hours/week using a computer were similar between groups. The PPTs measured at all 15 points in the neck-shoulder region were not significantly different between groups. There were no significant differences between groups neither in PPTs nor pain intensity induced by dynamic pressure algometry. No significant difference in PPT was observed in TA between groups. During CPM, a significant increase in PPT at TA was observed in both groups (P < 0.05) without significant differences between groups. For the chronic pain group, higher clinical pain intensity, lower PPT values from the neck-shoulder and higher pain intensity evoked by the roller were all correlated with less efficient descending pain modulation (P < 0.05). This suggests that the excitability of the central pain system is normal in a large group of computer users with low pain intensity
Bergeron-Vézina, Kayla; Corriveau, Hélène; Martel, Marylie; Harvey, Marie-Philippe; Léonard, Guillaume
2015-01-01
Abstract Despite its widespread clinical use, the efficacy of transcutaneous electrical nerve stimulation (TENS) remains poorly documented in elderly individuals. In this randomized, double-blind crossover study, we compared the efficacy of high-frequency (HF), low-frequency (LF), and placebo (P) TENS in a group of 15 elderly adults (mean age: 67 ± 5 years). The effect of HF-, LF-, and P-TENS was also evaluated in a group of 15 young individuals (26 ± 5 years; same study design) to validate the effectiveness of the TENS protocols that were used in the elderly group. Each participant came to the laboratory on 3 separate occasions to receive, in random order, HF-, LF-, and P-TENS. Pain intensity and pain perception thresholds were assessed before, during, and after TENS, using an experimental heat pain paradigm. For the young group, there was a significant decrease in pain intensity during and after HF- and LF-TENS when compared with baseline, with both HF- and LF-TENS being superior to P-TENS. In the older group, HF- and LF-TENS did not reduce pain when compared with baseline and no difference was observed between the 2 active TENS sessions and P-TENS. High-frequency, LF-, and P-TENS all increased pain thresholds in young individuals, whereas in older individuals, only LF-TENS increased pain thresholds. Taken together, these results suggest that TENS is effective in young, but not in older, individuals. Future studies should be conducted to confirm these results in pain populations and to identify strategies that could enhance the effect of TENS in the elderly. PMID:26101836
Greenspan, Joel D.; Slade, Gary D.; Bair, Eric; Dubner, Ronald; Fillingim, Roger B.; Ohrbach, Richard; Knott, Charlie; Mulkey, Flora; Rothwell, Rebecca; Maixner, William
2011-01-01
Many studies report that people with temporomandibular disorders (TMD) are more sensitive to experimental pain stimuli than TMD-free controls. Such differences in sensitivity are observed in remote body sites as well as in the orofacial region, suggesting a generalized upregulation of nociceptive processing in TMD cases. This large case-control study of 185 adults with TMD and 1,633 TMD-free controls measured sensitivity to painful pressure, mechanical cutaneous, and heat stimuli, using multiple testing protocols. Based on an unprecedented 36 experimental pain measures, 28 showed statistically significantly greater pain sensitivity in TMD cases than controls. The largest effects were seen for pressure pain thresholds at multiple body sites and cutaneous mechanical pain threshold. The other mechanical cutaneous pain measures and many of the heat pain measures showed significant differences, but with lesser effect sizes. Principal component analysis (PCA) of the pain measures derived from 1,633 controls identified five components labeled: (1) heat pain ratings, (2) heat pain aftersensations and tolerance, (3) mechanical cutaneous pain sensitivity, (4) pressure pain thresholds, and (5) heat pain temporal summation. These results demonstrate that, compared to TMD-free controls, chronic TMD cases are more sensitive to many experimental noxious stimuli at extra-cranial body sites, and provides for the first time the ability to directly compare the case-control effect sizes of a wide range of pain sensitivity measures. PMID:22074753
Pain and pain behavior in burning mouth syndrome: a pain diary study.
Forssell, Heli; Teerijoki-Oksa, Tuija; Kotiranta, Ulla; Kantola, Rosita; Bäck, Marjaliina; Vuorjoki-Ranta, Tiina-Riitta; Siponen, Maria; Leino, Ari; Puukka, Pauli; Estlander, Ann-Mari
2012-01-01
To characterize pain related to primary burning mouth syndrome (BMS) in terms of intensity, interference, and distress caused by the pain, as well as factors influencing the pain across a period of 2 weeks, and to study the use of coping and management strategies on a daily basis. Fifty-two female patients with primary BMS completed a 2-week pain diary. Pain intensity, interference, distress, and mood on a 0 to 10 numeric rating scale (NRS), as well as pain amplifying and alleviating factors, were recorded three times a day. The use of treatments (medication or other means) and coping strategies were recorded at the end of each day. Coefficient of variation, repeated measures analysis of variance, and correlative methods were used to assess the between- and within-subject variation, pain patterns, and associations between various pain scores. The overall mean pain intensity score of the 14 diary days was 3.1 (SD: 1.7); there was considerable variation in pain intensity between patients. Most patients experienced intermittent pain. On average, pain intensity increased from the morning to the evening. Intercorrelations between pain intensity, interference, distress, and mood were high, varying between rs = .75 and rs = .93 (P < .001). Pungent or hot food or beverages, stress, and tiredness were the most frequently mentioned pain-amplifying factors. The corresponding pain-alleviating factors were eating, sucking pastilles, drinking cold beverages, and relaxation. Thirty (58%) patients used pain medication and 35% reported using other means to alleviate their BMS pain. There was large variation in the use of coping strategies -between subjects. There were considerable differences in pain, in factors influencing the pain, and in pain behavior across BMS patients. This indicates that patient information and education as well as treatment of BMS pain should be individualized.
Bernardes, S F; Marques, S; Matos, M
2015-08-01
This study aimed to investigate the interplay between enduring and situational aging stereotype (AS) effects in older adults' self-reports of clinical and experimentally induced pain. We expected that, as compared with the situational activation of positive AS or a neutral condition, the activation of negative AS would lead to more severe self-reports of clinical pain (H1, hypothesis 1), higher cold pressor task (CPT) pain threshold (H2) and lower CPT pain tolerance (H3), especially among older adults who more strongly endorsed AS. This was a prospective study across two moments in time. At time 1 (T1), 52 older adults (Mage = 74.7; 51.9% women) filled out measures of cultural AS endorsement, clinical pain severity and interference. Three months afterwards (T2), some of these participants collaborated in an experimental study on the effects of AS activation on reported clinical pain (n = 40) and experimentally induced (using CPT) pain threshold and tolerance (n = 35). Our results supported H2, i.e., as compared with the activation of positive AS or a neutral condition, when negative AS were activated older adults showed higher CPT pain thresholds, but this effect was more salient among those who more strongly endorsed AS at T1. This study stresses the influence of cultural AS in older adults' pain experiences showing that the situational activation of negative AS greatly increases experimentally induced pain thresholds of elders who more strongly endorse those stereotypes. It also highlights the relevance of interventions at the level of the physical and/or social environments surrounding elders in pain. © 2014 European Pain Federation - EFIC®
Sensorimotor Incongruence in People with Musculoskeletal Pain: A Systematic Review.
Don, Sanneke; Voogt, Lennard; Meeus, Mira; De Kooning, Margot; Nijs, Jo
2017-01-01
Musculoskeletal pain has major public health implications, but the theoretical framework remains unclear. It is hypothesized that sensorimotor incongruence (SMI) might be a cause of long-lasting pain sensations in people with chronic musculoskeletal pain. Research data about experimental SMI triggering pain has been equivocal, making the relation between SMI and pain elusive. The aim of this study was to systematically review the studies on experimental SMI in people with musculoskeletal pain and healthy individuals. Preferred reporting items for systematic reviews and meta-analyses guidelines were followed. A systematic literature search was conducted using several databases until January 2015. To identify relevant articles, keywords regarding musculoskeletal pain or healthy subjects and the sensory or the motor system were combined. Study characteristics were extracted. Risk of bias was assessed using the Dutch Institute for Healthcare Improvement (CBO) checklist for randomized controlled trials, and level of evidence was judged. Eight cross-over studies met the inclusion criteria. The methodological quality of the studies varied, and populations were heterogeneous. In populations with musculoskeletal pain, outcomes of sensory disturbances and pain were higher during all experimental conditions compared to baseline conditions. In healthy subjects, pain reports during experimental SMI were very low or did not occur at all. Based on the current evidence and despite some methodological issues, there is no evidence that experimental SMI triggers pain in healthy individuals and in people with chronic musculoskeletal pain. However, people with chronic musculoskeletal pain report more sensory disturbances and pain during the experimental conditions, indicating that visual manipulation influences pain outcomes in this population. © 2016 World Institute of Pain.
Pain in Alzheimer's disease: A study of behavior and neural correlates
NASA Astrophysics Data System (ADS)
Beach, Paul Anthony
Alzheimer's disease (AD) is a devastating neurodegenerative disease characterized by insidious and progressive impairment of cognition, emotion, and memory. Though pain in patients with AD is a major medical concern it is under diagnosed and under treated in patients, compared to cognitively healthy elderly. Further complicating matters, subjective self-report of pain by becomes increasingly compromised with disease progression; this often leaves clinicians and caregivers no choice but to rely on discerning pain from behavior alone. Patients also report pain at a lower frequency and intensity than healthy seniors (HS). These findings, coupled with recognition that AD pathology affects many pain processing brain regions, have prompted examination of whether AD alters pain perception. While there is evidence that AD actually predisposes heightened perception of pain, several issues remain: experimental work is limited to a handful of studies, whose results have been inconsistent; few examinations of pain in AD have included patients with advanced disease; the neural mechanism underlying altered pain in AD is not clear. I addressed these gaps in the literature by examining subjective, behavioral, and autonomic pain responses in 33 HS and 38 patients with varying severities of AD. A subset of these subjects (24 HS and 20 AD) were scanned, using fMRI. I then determined how the functional connectivity of various resting-state networks (RSNs) were associated with measured pain responses. I found that AD patients rated low-level stimuli as more painful than HS. Also, patients, regardless of severity, showed greater degrees of pain behaviors than HS - both with respect to global behaviors as measured by a clinical pain scale and facial responses as measured by an experimental tool. In contrast, autonomic responses were blunted with advancing AD. Altered pain responses in AD were associated with altered function of RSNs involved in attention and internal mentation, affect
Competing effects of pain and fear of pain on postural control in low back pain?
Mazaheri, Masood; Heidari, Elham; Mostamand, Javid; Negahban, Hossein; van Dieen, Jaap H
2014-12-01
A cross-sectional, observational study. To determine whether pain and fear of pain have competing effects on postural sway in patients with low back pain (LBP). Competing effects of pain and pain-related fear on postural control can be proposed as the likely explanation for inconsistent results regarding postural sway in the LBP literature. We hypothesized that although pain might increase postural sway, fear of pain might reduce sway through an increased cognitive effort or increased cocontraction to restrict body movement. The cognitive strategy would be less effective under dual-task conditions and the cocontraction strategy was expected to be less effective when standing on a narrow base of support surface. Postural sway was measured in combined conditions of base of support (full and narrow) and cognitive loading (single and dual tasks) in 3 experimental groups with current LBP, recent LBP, and no LBP. Sway amplitude, path length, mean power frequency, and sample entropy were extracted from center-of-pressure data. The current-LBP group and recent-LBP group reported significantly different levels of pain, but similar levels of pain catastrophizing and kinesiophobia. The current-LBP group tended to display larger sway amplitudes in the anteroposterior direction compared with the other 2 groups. Mean power frequency values in mediolateral direction were lower in patients with the current LBP compared with recent LBP. Smaller sample entropy was found in the current-LBP group than the other groups in most experimental conditions, particularly when standing on a narrow base of support. Alterations of postural sway are mostly mediated by pain but not pain-related fear. LBP tends to increase sway amplitude, which seems to be counteracted by increased effort invested in postural control leading to decreased frequency and increased regularity of sway particularly under increased task demands. Cross-sectional study.
Schrooten, Martien G S; Wiech, Katja; Vlaeyen, Johan W S
2014-11-01
Individuals in pain often face the choice between avoiding pain and pursuing other equally valued goals. However, little is known about pain-related choice behavior and pain perception in goal conflict situations. Seventy-eight healthy volunteers performed a computerized task requiring repeated choices between incompatible options, differing in their effect on probability to receive painful stimulation and money. Depending on group assignment, participants chose between increased pain probability versus decreased money probability (avoidance-avoidance conflict situation); decreased pain probability versus increased money probability (approach-approach conflict situation); or decrease versus increase in both probabilities (double approach/avoidance conflict situation). During the choice task, participants rated painfulness, unpleasantness, threat, and fearfulness associated with the painful stimulation and how they felt. Longer choice latency and more choice switching were associated with higher retrospective ratings of conflict and of decision difficulty, and more equal importance placed on pain avoidance and earning money. Groups did not differ in choice behavior, pain stimulus ratings, or affect. Across groups, longer choice latencies were nonsignificantly associated with higher pain, unpleasantness, threat, and fearfulness. In the avoidance-avoidance group, more choice switching was associated with higher pain-related threat and fearfulness, and with more negative affect. These results of this study suggest that associations between choice behaviors, pain perception, and affect depend on conflict situation. We present a first experimental demonstration of the relationship between pain-related choice behaviors, pain, and affect in different goal conflict situations. This experimental approach allows us to examine these relationships in a controlled fashion. Better understanding of pain-related goal conflicts and their resolution may lead to more effective pain
Multiple sites and actions of gabapentin-induced relief of ongoing experimental neuropathic pain.
Bannister, Kirsty; Qu, Chaoling; Navratilova, Edita; Oyarzo, Janice; Xie, Jennifer Yanhua; King, Tamara; Dickenson, Anthony H; Porreca, Frank
2017-12-01
Gabapentin (GBP) is a first-line therapy for neuropathic pain, but its mechanisms and sites of action remain uncertain. We investigated GBP-induced modulation of neuropathic pain following spinal nerve ligation (SNL) in rats. Intravenous or intrathecal GBP reversed evoked mechanical hypersensitivity and produced conditioned place preference (CPP) and dopamine (DA) release in the nucleus accumbens (NAc) selectively in SNL rats. Spinal GBP also significantly inhibited dorsal horn wide-dynamic-range neuronal responses to a range of evoked stimuli in SNL rats. By contrast, GBP microinjected bilaterally into the rostral anterior cingulate cortex (rACC), produced CPP, and elicited NAc DA release selectively in SNL rats but did not reverse tactile allodynia and had marginal effects on wide-dynamic-range neuronal activity. Moreover, blockade of endogenous opioid signaling in the rACC prevented intravenous GBP-induced CPP and NAc DA release but failed to block its inhibition of tactile allodynia. Gabapentin, therefore, can potentially act to produce its pain relieving effects by (a) inhibition of injury-induced spinal neuronal excitability, evoked hypersensitivity, and ongoing pain and (b) selective supraspinal modulation of affective qualities of pain, without alteration of reflexive behaviors. Consistent with previous findings of pain relief from nonopioid analgesics, GBP requires engagement of rACC endogenous opioid circuits and downstream activation of mesolimbic reward circuits reflected in learned pain-motivated behaviors. These findings support the partial separation of sensory and affective dimensions of pain in this experimental model and suggest that modulation of affective-motivational qualities of pain may be the preferential mechanism of GBP's analgesic effects in patients.
Multiple sites and actions of gabapentin-induced relief of ongoing experimental neuropathic pain
Bannister, Kirsty; Qu, Chaoling; Navratilova, Edita; Oyarzo, Janice; Xie, Jennifer Yanhua; King, Tamara; Dickenson, Anthony H.; Porreca, Frank
2017-01-01
Gabapentin is a first-line therapy for neuropathic pain but its mechanisms and sites of action remain uncertain. We investigated gabapentin-induced modulation of neuropathic pain following spinal nerve ligation (SNL) in rats. Intravenous or intrathecal gabapentin reversed evoked mechanical hypersensitivity, produced conditioned place preference (CPP) and dopamine release in the nucleus accumbens (NAc) selectively in SNL rats. Spinal gabapentin also significantly inhibited dorsal horn wide dynamic range (WDR) neuronal responses to a range of evoked stimuli in SNL rats. In contrast, gabapentin microinjected bilaterally into the rostral anterior cingulate cortex (rACC), produced CPP and elicited NAc dopamine release selectively in SNL rats but did not reverse tactile allodynia and had marginal effects on WDR neuronal activity. Moreover, blockade of endogenous opioid signaling in the rACC prevented intravenous gabapentin-induced CPP and NAc dopamine release but failed to block its inhibition of tactile allodynia. Gabapentin therefore can potentially act to produce its pain relieving effects by (a) inhibition of injury-induced spinal neuronal excitability, evoked hypersensitivity and ongoing pain and (b) selective supraspinal modulation of affective qualities of pain, without alteration of reflexive behaviors. Consistent with previous findings of pain relief from non-opioid analgesics, gabapentin requires engagement of rACC endogenous opioid circuits and downstream activation of mesolimbic reward circuits reflected in learned pain motivated behaviors. These findings support the partial separation of sensory and affective dimensions of pain in this experimental model and suggest that modulation of affective-motivational qualities of pain may be the preferential mechanism of gabapentin’s analgesic effects in patients. PMID:28832395
Trost, Z; Scott, W; Lange, J M; Manganelli, L; Bernier, E; Sullivan, M J
2014-03-01
Perceptions of injustice are linked with poorer physical and psychological outcomes in the context of pain and injury. Violations of injustice can arise out of violations of just world belief (JWB). However, no study has yet examined whether JWB moderates the effect of justice violation on pain experience. The current study examined the effect of an experimental justice violation on acute pain outcomes and whether JWB moderated this effect. Participants completed the JWB scale and then engaged in two cold pressor tasks (CPT). Half the participants were told that the second CPT immersion was part of standard protocol; the other half were told that the painful procedure had to be repeated due to experimenter negligence. Participants provided report of pain intensity following each CPT immersion. Video records of participants undergoing the CPT were coded for presence and duration of pain behaviour. Exposure to the justice violation resulted in elevated pain intensity from the first to the second immersion only among participants with high JWB. For participants with low JWB and participants in the control condition, there was no significant difference in pain intensity across immersions. Control participants showed a decrease in pain behaviour from the first to the second immersion. In the negligence/ justice violation condition, reductions in pain behaviour were observed only among participants with low JWB. Our results indicate that individuals with high JWB may show particularly adverse reactions in response to justice violations in the context of acute pain experience. © 2013 European Pain Federation - EFIC®
Nguyen, Ly Thuy; Alexander, Kimberly; Yates, Patsy
2018-06-01
To assess the feasibility of conducting a trial of a psychoeducational intervention involving the provision of tailored information and coaching to improve management of a cancer-related symptom cluster (fatigue, pain, and sleep disturbance) and reduce symptom cluster impacts on patient health outcomes in the Vietnamese context and to undertake a preliminary evaluation of the intervention. A parallel-group single-blind pilot quasi-experimental trial was conducted with 102 cancer patients in one Vietnamese hospital. The intervention group received one face-to-face session and two phone sessions delivered by a nurse one week apart, and the comparison group received usual care. Patient outcomes were measured at baseline before the chemotherapy cycle and immediately preceding the next chemotherapy cycle. Separate linear mixed models were used to evaluate the impact of the intervention on total symptom cluster severity, symptom scores, functional status, depressive symptoms, and health-related quality of life. The study design was feasible with a recruitment rate of 22.6% and attrition rate of 9.8%. Compared to the control group, the intervention group showed a significant reduction in symptom cluster severity, fatigue severity, fatigue interference, sleep disturbance, depression, and anxiety. Significant differences were not observed for pain severity, pain interference, functional status, and health-related quality of life. The intervention was acceptable to the study population, with a high attendance rate of 78% and adherence rate of 95.7%. On the basis of the present study findings, future randomized controlled trials are needed to test the effectiveness of a symptom cluster psychoeducational intervention in Vietnam. Copyright © 2018 American Academy of Hospice and Palliative Medicine. Published by Elsevier Inc. All rights reserved.
Vlaeyen, Johan W S; Morley, Stephen; Crombez, Geert
2016-11-01
Pain is an unpleasant sensory and emotional experience urging the individual to take action to restore the integrity of the body. The transition from a common episode of acute pain to a state of intermittent or chronic pain has been a constant preoccupation of researchers and clinicians alike. In this review, we approach chronic pain from a modern learning perspective that incorporates cognitive, affective, behavioral and motivational aspects. We view pain as a biologically hard-wired signal of bodily harm that competes with other demands in the person's environment. The basic tenet is that pain urges people to interrupt ongoing activity, elicits protective responses that paradoxically increase interference with daily activities, and compromises the sense of self. Here we briefly summarize existing evidence showing how pain captures attention, and how attention for pain can be controlled. We also consider pain as a strong motivator for learning, and review the recent evidence on the acquisition and generalization of pain-related fear and avoidance behavior, which are likely to interfere with daily life activities. We highlight the paradoxical effects of pain avoidance behavior, and review treatment effects of exposure in vivo. A generally neglected area of research is the detrimental consequences of repeated interference by pain with daily activities on one's sense of "self". We end this review with a plea for the implementation of single-case experimental designs as a means to help customize and develop novel cognitive-behavioral treatments for individuals for chronic pain aimed at reducing the suffering of this large group of individuals. Copyright © 2016 Elsevier Ltd. All rights reserved.
Comparative efficacy of oral meloxicam and phenylbutazone in 2 experimental pain models in the horse
Banse, Heidi; Cribb, Alastair E.
2017-01-01
The efficacy of oral phenylbutazone [PBZ; 4.4 mg/kg body weight (BW), q12h], a non-selective non-steroidal anti-inflammatory drug (NSAID), and oral meloxicam (MXM; 0.6 mg/kg BW, q24h), a COX-2 selective NSAID, were evaluated in 2 experimental pain models in horses: the adjustable heart bar shoe (HBS) model, primarily representative of mechanical pain, and the lipopolysaccharide-induced synovitis (SYN) model, primarily representative of inflammatory pain. In the HBS model, PBZ reduced multiple indicators of pain compared with the placebo and MXM. Meloxicam did not reduce indicators of pain relative to the placebo. In the SYN model, MXM and PBZ reduced increases in carpal skin temperature compared to the placebo. Meloxicam reduced lameness scores and lameness-induced changes in head movement compared to the placebo and PBZ. Phenylbutazone reduced lameness-induced change in head movement compared to the placebo. Overall, PBZ was more effective than MXM at reducing pain in the HBS model, while MXM was more effective at reducing pain in the SYN model at the oral doses used. PMID:28216685
Hirata, Rogério Pessoto; Ervilha, Ulysses Fernandes; Arendt-Nielsen, Lars; Graven-Nielsen, Thomas
2011-08-01
Musculoskeletal pain impairs postural control and stability. Nine subjects stood as quietly as possible on a moveable force platform before, during, and after experimental pain in the right leg muscles. A moveable force platform was used to measure the center of pressure and provided unexpected perturbations. Lower limb muscle activity, joint angles, and foot pressure distributions were measured. Hypertonic saline was used to induce pain in the vastus lateralis, vastus medialis, or biceps femoris muscle of the right leg. Compared to baseline and control sessions, pain in the knee extensor muscles during quiet standing evoked: 1) larger sway area, greater medial-lateral center of pressure displacement and higher speed (P < .05); 2) increased sway displacement in the anterior-posterior direction (P < .05); and 3) increased electromyography (EMG) activity for left tibialis anterior and left erector spinae muscles (P < .05). Pain provoked longer time to return to an equilibrium posture after forward EMG activity for, and pain in vastus medialis muscle decreased the time for the maximum hip flexion during this perturbation (P < .05). These results show that muscle pain impairs postural stability during quiet standing and after unexpected perturbation, which suggest that people suffering from leg muscle pain are more vulnerable to falls. This article presents the acute responses to leg muscle pain on the postural control. This measure could potentially help clinicians who seek to assess how pain responses may contribute to patient's postural control and stability during quiet standing and after recovering from unexpected perturbations. Copyright © 2011 American Pain Society. Published by Elsevier Inc. All rights reserved.
Fowler, Stephanie L; Rasinski, Heather M; Geers, Andrew L; Helfer, Suzanne G; France, Christopher R
2011-04-01
Prior research has found that sex differences in pain are partially due to individual variations in gender roles. In a laboratory study, we tested the hypothesis that the presence of covert gender role cues can also moderate the extent to which women and men experience pain. Specifically, we varied gender role cues by asking male and female participants to write about instances in which they behaved in a stereotypically feminine, masculine, or neutral manner. Pain and cardiovascular reactivity to the cold pressor task were then assessed. Results revealed that, when primed with femininity, men reported less pain and anxiety from the cold pressor task than women. However, no differences existed between the sexes in the masculine or neutral prime conditions. The results indicate that covert gender cues can alter pain reports. Further, at least in some situations, feminine role cues may be more influential on pain reports than masculine role cues.
[Pain in humans: experimental facts and hypotheses].
Cesaro, P
1994-09-15
The description of painful phenomena in humans has to take into account its different components: sensory component (relevant to nociception), affective and emotional components. Nociceptor's (physiology is best understood with electrophysiological and neurochemical methods allowing a clear description of hyperalgesia, with its peripheral and spinal mechanisms. A functional model is partly available to explain allodynia, spontaneous burning pain and lightning pain, the three main consequences following deafferentation. At the thalamo-cortical level, one can describe nociceptive pathways and other pathways or neuronal networks involved in the affective and emotional components of pain.
Hormones in pain modulation and their clinical implications for pain control: a critical review.
Chen, Xueyin; Zhang, Jinyuan; Wang, Xiangrui
2016-07-01
Recently, more and more studies have found that pain generation, transmission and modulation are under hormonal regulation. Indeed, hormonal dysregulation is a common component of chronic pain syndromes. Studies have attempted to determine whether the relationship between the pain and its perception and hormones is a causative relationship and how these processes interrelate. This review summarizes and analyzes the current experimental data and provides an overview of the studies addressing these questions. The relationship between pain perception and endocrine effects suggests that hormones can be used as important biomarkers of chronic pain syndromes and/or be developed into therapeutic agents in the fight against pain.
[Patient careers in the orthopedic pain treatment. Sociological studies on pain behavior].
Göckenjan, G; Dreßke, S; Pfankuch, O
2013-09-01
Based on case histories the following study raises the question why some pain patients remain permanently on the path of specialist pain treatment after initial treatment whereas other patients with similar pain reports do not. In this study 134 qualitative interviews were conducted in order to research patient career paths. The study population included patients with back pain recruited from different orthopedic care settings and included persons with back pain from a general population not involved in specialized pain treatment. Patient career paths within medical care settings are effective in socializing and transforming the subjects. In the course of medical treatment patients learn their rights and obligations and subsequently acquire habits of typical pain behavior both in medical and domestic arrangements. Patients learn to formulate and preserve their interests and learn to align the different expectations which results in increasing identification with the career path. Conceptions of pain and pain behavior are formed in the course of patient careers while this is not necessarily a conscious or reflected process. As an unintended consequence it evolves into pain acting within the patient that integrates patients into distinct care milieus and holds them tight in the respective pain care. In these cases pain patients and their doctors fall so to say into a pain trap.
Reconsidering the International Association for the Study of Pain definition of pain.
Cohen, Milton; Quintner, John; van Rysewyk, Simon
2018-03-01
The definition of pain promulgated by the International Association for the Study of Pain (IASP) is widely accepted as a pragmatic characterisation of that human experience. Although the Notes that accompany it characterise pain as "always subjective," the IASP definition itself fails to sufficiently integrate phenomenological aspects of pain. This essay reviews the historical development of the IASP definition, and the commentaries and suggested modifications to it over almost 40 years. Common factors of pain experience identified in phenomenological studies are described, together with theoretical insights from philosophy and biology. A fuller understanding of the pain experience and of the clinical care of those experiencing pain is achievable through greater attention to the phenomenology of pain, the social "intersubjective space" in which pain occurs, and the limitations of language. Based on these results, a revised definition of pain is offered: Pain is a mutually recognizable somatic experience that reflects a person's apprehension of threat to their bodily or existential integrity.
Dagsdóttir, Lilja Kristín; Skyt, Ina; Vase, Lene; Baad-Hansen, Lene; Castrillon, Eduardo; Svensson, Peter
2015-09-01
Patients suffering from persistent orofacial pain may sporadically report that the painful area feels "swollen" or "differently," a phenomenon that may be conceptualized as a perceptual distortion because there are no clinical signs of swelling present. Our aim was to investigate whether standardized experimental pain and sensory deprivation of specific orofacial test sites would lead to changes in the size perception of these face areas. Twenty-four healthy participants received either 0.2 mL hypertonic saline (HS) or local anesthetics (LA) into six regions (buccal, mental, lingual, masseter muscle, infraorbital and auriculotemporal nerve regions). Participants estimated the perceived size changes in percentage (0 % = no change, -100 % = half the size or +100 % = double the size), and somatosensory function was checked with tactile stimuli. The pain intensity was rated on a 0-10 Verbal Numerical Rating Scale (VNRS), and sets of psychological questionnaires were completed. HS and LA were associated with significant self-reported perceptual distortions as indicated by consistent increases in perceived size of the adjacent face areas (P ≤ 0.050). Perceptual distortion was most pronounced in the buccal region, and the smallest increase was observed in the auriculotemporal region. HS was associated with moderate levels of pain VNRS = 7.3 ± 0.6. Weak correlations were found between HS-evoked perceptual distortion and level of dissociation in two regions (P < 0.050). Experimental pain and transient sensory deprivation evoked perceptual distortions in all face regions and overall demonstrated the importance of afferent inputs for the perception of the face. We propose that perceptual distortion may be an important phenomenon to consider in persistent orofacial pain conditions.
Operant conditioning of facial displays of pain.
Kunz, Miriam; Rainville, Pierre; Lautenbacher, Stefan
2011-06-01
The operant model of chronic pain posits that nonverbal pain behavior, such as facial expressions, is sensitive to reinforcement, but experimental evidence supporting this assumption is sparse. The aim of the present study was to investigate in a healthy population a) whether facial pain behavior can indeed be operantly conditioned using a discriminative reinforcement schedule to increase and decrease facial pain behavior and b) to what extent these changes affect pain experience indexed by self-ratings. In the experimental group (n = 29), the participants were reinforced every time that they showed pain-indicative facial behavior (up-conditioning) or a neutral expression (down-conditioning) in response to painful heat stimulation. Once facial pain behavior was successfully up- or down-conditioned, respectively (which occurred in 72% of participants), facial pain displays and self-report ratings were assessed. In addition, a control group (n = 11) was used that was yoked to the reinforcement plans of the experimental group. During the conditioning phases, reinforcement led to significant changes in facial pain behavior in the majority of the experimental group (p < .001) but not in the yoked control group (p > .136). Fine-grained analyses of facial muscle movements revealed a similar picture. Furthermore, the decline in facial pain displays (as observed during down-conditioning) strongly predicted changes in pain ratings (R(2) = 0.329). These results suggest that a) facial pain displays are sensitive to reinforcement and b) that changes in facial pain displays can affect self-report ratings.
Sapir, Shimon; Pud, Dorit
2008-01-01
To assess the effect of tonic pain stimulation on auditory processing of speech-relevant acoustic signals in healthy pain-free volunteers. Sixty university students, randomly assigned to either a thermal pain stimulation (46 degrees C/6 min) group (PS) or no pain stimulation group (NPS), performed a rate change detection task (RCDT) involving sinusoidally frequency-modulated vowel-like signals. Task difficulty was manipulated by changing the rate of the modulated signals (henceforth rate). Perceived pain intensity was evaluated using a visual analog scale (VAS) (0-100). Mean pain rating was approximately 33 in the PS group and approximately 3 in the NPS group. Pain stimulation was associated with poorer performance on the RCDT, but this trend was not statistically significant. Performance worsened with increasing rate of signal modulation in both groups (p < 0.0001), with no pain by rate interaction. The present findings indicate a trend whereby mild or moderate pain appears to affect auditory processing of speech-relevant acoustic signals. This trend, however, was not statistically significant. It is possible that more intense pain would yield more pronounced (deleterious) effects on auditory processing, but this needs to be verified empirically.
Chen, Hsing-Hsia; Yeh, Mei-Ling; Yang, Hui-Ju
2005-07-01
This study aimed to develop a multimedia video CD (VCD) of patient-controlled analgesia (PCA) and test its effects on pain knowledge and pain relief in patients receiving surgery. This multimedia VCD of PCA was created to convey fundamental knowledge to both patients and their family members and help patients properly utilize PCA devices to relieve pain and improve recovery. The content of multimedia VCD of PCA included pre-admission pain education, introduction of PCA, nursing care procedures, and questions and answers. This study used a quasi-experimental research design to test effects of the multimedia education program in the experimental group of 30 subjects compared to the control subjects of equal number (without the multimedia VCD of PCA). (1) The intervention of multimedia VCD of PCA resulted in a statistically significant difference in pain knowledge between the experimental and control groups. (2) Subjects in the experimental group obtained a better outcome of pain relief compared to control subjects. (3) Subjects in the experimental group indicated that the multimedia VCD of PCA indeed helped them effectively operate their PCA devices to relieve surgery pain. The clinical application of the multimedia VCD of PCA could help patients improve knowledge on pain, learn how to use PCA devices, achieve proper pain relief, and increase effectiveness of recovery activities.
The Effectiveness of Hypnosis Intervention for Labor: An Experimental Study.
Beevi, Zuhrah; Low, Wah Yun; Hassan, Jamiyah
2017-10-01
Hypnosis has been shown to help pregnant women experience improved labor and postpartum periods. The present study compares the differences between experimental (n = 23) and control groups (n = 22) on specific variables measured both during labor and 24 hr postpartum. The participants in the experimental group received the hypnosis intervention at weeks 16, 20, 28, and 36 of pregnancy, while those in the control group received only routine antenatal care. The data collected at the labor stage describe the length of the labor stage, pain relief used during labor, the method of delivery, and the type of assisted vaginal delivery. Within 24 hr of delivery, data on neonatal birth weight, neonatal Apgar scores, and self-reported pain were obtained. The labor stage results showed no significant differences in the length of the second and third stages of labor. Although the participants in the experimental group reported higher pain levels immediately prior to, during, and immediately after delivery, their use of pethidine during labor was significantly lower than the control group participants. None of the experimental group participants opted for an epidural, and they had a greater number of assisted vaginal deliveries than the control group participants. The 24 hr postpartum results showed that the neonates of the experimental group participants had nonsignificantly higher Apgar scores than those of the women in the control group. Group differences in neonatal weight were not significant. The results of the present study indicate that hypnosis is useful for assisting pregnant women during labor and the postpartum period.
Manipulating the Placebo Response in Experimental Pain by Altering Doctor’s Performance Style
Czerniak, Efrat; Biegon, Anat; Ziv, Amitai; Karnieli-Miller, Orit; Weiser, Mark; Alon, Uri; Citron, Atay
2016-01-01
Background: Performance is paramount in traditional healing rituals. From a Western perspective, such performative behavior can be understood principally as inducing patients’ faith in the performer’s supernatural healing powers and effecting positive changes through the same mechanisms attributed to the placebo response, which is defined as improvement of clinical outcome in individuals receiving inactive treatment. Here we examined the possibility of using theatrical performance tools, including stage directions and scripting, to reproducibly manipulate the style and content of a simulated doctor–patient encounter and influence the placebo response in experimental pain. Methods: A total of 122 healthy volunteers (18–45 years, 76 men) exposed to experimental pain (the cold pressor test) were assessed for pain threshold and tolerance before and after receiving a placebo cream from a “doctor” impersonated by a trained actor. The actor alternated between two distinct scripts and stage directions, i.e., performance styles created by a theater director/playwright, one emulating a standard doctor–patient encounter (scenario A) and the other emphasizing attentiveness and strong suggestion, elements also present in ritual healing (scenario B). The placebo response size was calculated as the %difference in pain threshold and tolerance after exposure relative to baseline. In addition, subjects demonstrating a ≥30% increase in pain threshold or tolerance relative to baseline were defined as responders. Each encounter was videotaped in its entirety. Results: Inspection of the videotapes confirmed the reproducibility and consistency of the distinct scenarios enacted by the “doctor”-performer. Furthermore, scenario B resulted in a significant increase in pain threshold relative to scenario A. Interestingly, this increase derived from the placebo responder subgroup; as shown by two-way analysis of variance (performance style, F = 4.30; p = 0.040; η2 = 0
La Touche, Roy; Paris-Alemany, Alba; Gil-Martínez, Alfonso; Pardo-Montero, Joaquín; Angulo-Díaz-Parreño, Santiago; Fernández-Carnero, Josué
2015-03-05
Recent research has shown a relationship of craniomandibular disability with neck-pain-related disability has been shown. However, there is still insufficient information demonstrating the influence of neck pain and disability in the sensory-motor activity in patients with headache attributed to temporomandibular disorders (TMD). The purpose of this study was to investigate the influence of neck-pain-related disability on masticatory sensory-motor variables. An experimental case-control study investigated 83 patients with headache attributed to TMD and 39 healthy controls. Patients were grouped according to their scores on the neck disability index (NDI) (mild and moderate neck disability). Initial assessment included the pain catastrophizing scale and the Headache Impact Test-6. The protocol consisted of baseline measurements of pressure pain thresholds (PPT) and pain-free maximum mouth opening (MMO). Individuals were asked to perform the provocation chewing test, and measurements were taken immediately after and 24 hours later. During the test, patients were assessed for subjective feelings of fatigue (VAFS) and pain intensity. VAFS was higher at 6 minutes (mean 51.7; 95% CI: 50.15-53.26) and 24 hours after (21.08; 95% CI: 18.6-23.5) for the group showing moderate neck disability compared with the mild neck disability group (6 minutes, 44.16; 95% CI 42.65-45.67/ 24 hours after, 14.3; 95% CI: 11.9-16.7) and the control group. The analysis shows a decrease in the pain-free MMO only in the group of moderate disability 24 hours after the test. PPTs of the trigeminal region decreased immediately in all groups, whereas at 24 hours, a decrease was observed in only the groups of patients. PPTs of the cervical region decreased in only the group with moderate neck disability 24 hours after the test. The strongest negative correlation was found between pain-free MMO immediately after the test and NDI in both the mild (r = -0.49) and moderate (r = -0.54) neck disability
Reconsidering the International Association for the Study of Pain definition of pain
Cohen, Milton; Quintner, John; van Rysewyk, Simon
2018-01-01
Abstract Introduction: The definition of pain promulgated by the International Association for the Study of Pain (IASP) is widely accepted as a pragmatic characterisation of that human experience. Although the Notes that accompany it characterise pain as “always subjective,” the IASP definition itself fails to sufficiently integrate phenomenological aspects of pain. Methods: This essay reviews the historical development of the IASP definition, and the commentaries and suggested modifications to it over almost 40 years. Common factors of pain experience identified in phenomenological studies are described, together with theoretical insights from philosophy and biology. Results: A fuller understanding of the pain experience and of the clinical care of those experiencing pain is achievable through greater attention to the phenomenology of pain, the social “intersubjective space” in which pain occurs, and the limitations of language. Conclusion: Based on these results, a revised definition of pain is offered: Pain is a mutually recognizable somatic experience that reflects a person's apprehension of threat to their bodily or existential integrity. PMID:29756084
Influence of exercise on visceral pain: an explorative study in healthy volunteers
van Weerdenburg, Laura JGM; Brock, Christina; Drewes, Asbjørn Mohr; van Goor, Harry; de Vries, Marjan; Wilder-Smith, Oliver HG
2017-01-01
Background and objectives Contradictory results have been found about the effect of different exercise modalities on pain. The aim of this study was to investigate the early effects of aerobic and isometric exercise on different types of experimental pain, including visceral pain, compared to an active control condition. Methods Fifteen healthy subjects (6 women, mean [standard deviation] age 25 [6.5] years) completed 3 interventions consisting of 20 minutes of aerobic cycling, 12 minutes of isometric knee extension and a deep breathing procedure as active control. At baseline and after each intervention, psychophysical tests were performed, including electrical stimulation of the esophagus, pressure pain thresholds and the cold pressor test as a measure for conditioned pain modulation. Participants completed the Medical Outcome Study Short-Form 36 and State-Trait Anxiety Inventory prior to the experiments. Data were analyzed using two-way repeated measures analysis of variance. Results No significant differences were found for the psychophysical tests after the interventions, compared to baseline pain tests and the control condition. Conclusion No hypoalgesic effect of aerobic and isometric exercise was found. The evidence for exercise-induced hypoalgesia appears to be not as consistent as initially thought, and caution is recommended when interpreting the effects of exercise on pain. PMID:28096689
Tsur, Noga; Defrin, Ruth; Ginzburg, Karni
Studies suggest that torture survivors often experience long-term chronic pain and increased pain perception. However, it is unclear whether the actual experience of torture or rather the subsequent posttraumatic stress disorder (PTSD) explains these pain problems. Furthermore, although catastrophic and fearful orientations to pain have been suggested to play a significant role in the association between trauma and pain, the underlying mechanisms remain unclear. This study examined whether chronic pain and pain perception among torture survivors are associated with torture experience or PTSD and whether catastrophic and fearful orientations mediate or moderate these associations. Fifty-nine ex-prisoners of war who underwent torture and 44 matched veterans participated in this study. Pain perception was evaluated by assessing pain threshold and reactivity to experimental suprathreshold noxious stimuli. Participants completed self-administered questionnaires assessing PTSD, chronic pain, pain catastrophizing, and fear of pain. Although chronic pain was associated with PTSD (0.44 < β < 0.49, p < .002), increased pain perception was correlated with torture (0.33 < β < 0.65, p < .05). Pain catastrophizing was found to mediate the association between PTSD and chronic pain (β = 0.18 and 0.19, respectively; p < .05). Fear of pain moderated the association between torture and pain perception (β = 0.41 and 0.42, respectively; p < .017). The findings suggest that chronic pain is contingent upon the psychological toll of torture, that is, PTSD. This study also indicates that PTSD exacerbates catastrophic orientation, which in turn may amplify chronic pain. Reactivity to experimental noxious stimuli was related to previous experiences of torture, which enhances perceived pain intensity when interacting with a fearful pain orientation. These findings highlight the significance of orientation to bodily experiences after trauma.
Influence of muscle pain tolerance on muscle pain threshold in experimental tooth clenching in man.
Christensen, L V
1979-07-01
Ten adults and ten children exercised maximal voluntary tooth clenching until pains appeared in the jaw muscles, i.e. the muscle pain threshold of tooth clenching was determined. Subsequently, the subjects were instructed to exercise tooth clenching until they were forced to stop because of intolerable pains and exhaustion of the contracting muscles, i.e. the muscle pain tolerance of tooth clenching was recorded, and during these bouts of clenching the pain tolerance of tooth clenching was recorded, and during these bouts of clenching the pain threshold was also determined. In adults, determination of the pain tolerance decreased the pain threshold by 19%, and in children it either decreased the pain threshold by 20% or increased it by 56%. It is proposed to introduce the muscle pain tolerance of tooth clenching as an adjunct in the clinical examination of cases of facial pains presumed to originate from the jaw muscles, but the test should be interpreted with caution.
Bennett, Marc P.; Meulders, Ann; Baeyens, Frank; Vlaeyen, Johan W. S.
2015-01-01
Patients with chronic pain are often fearful of movements that never featured in painful episodes. This study examined whether a neutral movement’s conceptual relationship with pain-relevant stimuli could precipitate pain-related fear; a process known as symbolic generalization. As a secondary objective, we also compared experiential and verbal fear learning in the generalization of pain-related fear. We conducted an experimental study with 80 healthy participants who were recruited through an online experimental management system (Mage = 23.04 years, SD = 6.80 years). First, two artificial categories were established wherein nonsense words and joystick arm movements were equivalent. Using a between-groups design, nonsense words from one category were paired with either an electrocutaneous stimulus (pain-US) or threatening information, while nonsense words from the other category were paired with no pain-US or safety information. During a final testing phase, participants were prompted to perform specific joystick arm movements that were never followed by a pain-US, although they were informed that it could occur. The results showed that movements equivalent to the pain-relevant nonsense words evoked heightened pain-related fear as measured by pain-US expectancy, fear of pain, and unpleasantness ratings. Also, experience with the pain-US evinced stronger acquisition and generalization compared to experience with threatening information. The clinical importance and theoretical implications of these findings are discussed. PMID:25983704
Dubois, Jean-Daniel; Cantin, Vincent; Piché, Mathieu; Descarreaux, Martin
2016-01-01
Despite an elusive pathophysiology, common characteristics are often observed in individuals with chronic low back pain (LBP). These include psychological symptoms, altered pain perception, altered pain modulation and altered muscle activation. These factors have been explored as possible determinants of disability, either separately or in cross-sectional studies, but were never assessed in a single longitudinal study. Therefore, the objective was to determine the relative contribution of psychological and neurophysiological factors to future disability in individuals with past LBP. The study included two experimental sessions (baseline and six months later) to assess cutaneous heat pain and pain tolerance thresholds, pain inhibition, as well as trunk muscle activation. Both sessions included the completion of validated questionnaires to determine clinical pain, disability, pain catastrophizing, fear-avoidance beliefs and pain vigilance. One hundred workers with a history of LBP and 19 healthy individuals took part in the first experimental session. The second experimental session was exclusively conducted on workers with a history of LBP (77/100). Correlation analyses between initial measures and disability at six months were conducted, and measures significantly associated with disability were used in multiple regression analyses. A first regression analysis showed that psychological symptoms contributed unique variance to future disability (R2 = 0.093, p = .009). To control for the fluctuating nature of LBP, a hierarchical regression was conducted while controlling for clinical pain at six months (R2 = 0.213, p < .001) where pain inhibition contributed unique variance in the second step of the regression (R2 change = 0.094, p = .005). These results indicate that pain inhibition processes may constitute potential targets for treatment to alleviate future disability in individuals with past or present LBP. Then again, the link between psychological symptoms and
Jones, Matthew D; Booth, John; Taylor, Janet L; Barry, Benjamin K
2016-10-01
In healthy individuals and people with chronic pain, an inverse association between physical activity level and pain has been reported. Associations between objectively measured fitness and pain have also been found in people with chronic pain, but it is not clear whether the same relations are apparent in healthy individuals. The purpose of the present study was to examine the relation between aerobic capacity and pain in healthy individuals. Pressure pain threshold, ischemic pain tolerance, and pain ratings during ischemia were assessed and analyzed in relation to aerobic capacity in 35 healthy individuals. Correlation and multiple linear regression were used to analyze the data. Data from previous similar studies in healthy individuals and people with fibromyalgia were extracted and collated by literature review to support interpretation of the experimental data. No relation was found between aerobic capacity and any measure of pain, with the exception of a moderate inverse association between aerobic capacity and lower body pressure pain threshold in males (r = -0.58, P = 0.03) when data from male and female participants were analyzed separately. The limited association between aerobic capacity and quantitative sensory testing of pain was consistent with the data synthesis from previous studies of healthy individuals but differed from studies of people with fibromyalgia. Aerobic capacity is unrelated to pain in healthy young adults. For people with chronic pain, the negative relation between aerobic capacity and pain presumably arises from the underlying pathophysiology and/or associated behaviors of the disease process. © 2016 American Academy of Pain Medicine. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.
Wu, Jackson S Y; Beaton, Dorcas; Smith, Peter M; Hagen, Neil A
2010-02-01
Bone metastases are prevalent, painful, and carry a poorer prognosis for pain control compared with other cancer pain syndromes. Standard tools to measure pain have not been validated in this patient population, and particular subgroups with more challenging symptoms have yet to be identified and studied. The objectives of this study were 1) to validate the psychometric properties of the Brief Pain Inventory (BPI) and its Pain and Interference subscales in patients with clinically significant metastatic bone pain requiring palliative radiotherapy and 2) to examine differences in BPI subscales among predefined subgroups of bone metastases patients. A total of 258 patients evaluated and treated through a rapid access radiation therapy clinic between July 2002, and November 2006, were included in the analysis. High internal consistency of the BPI subscales of Pain, Activity interference, and Affect interference was demonstrated by Cronbach's alpha between 0.81 and 0.89. Removing sleep interference improved model fit in confirmatory factor analysis. The BPI revealed an alarming pattern in patients with lower body metastases, who reported substantial interference of activity even though pain levels were mild or moderate. Such patients may require prompt clinical attention to better meet their needs. Finally, the allocation of interference from sleep within the BPI framework, in our population of pain patients, requires further study. Copyright 2010 U.S. Cancer Pain Relief Committee. Published by Elsevier Inc. All rights reserved.
Foot massage: effectiveness on postoperative pain in breast surgery patients.
Ucuzal, Meral; Kanan, Nevin
2014-06-01
The aim of this study was to determine the effect of foot massage on pain after breast surgery, and provide guidance for nurses in nonpharmacologic interventions for pain relief. This was a quasiexperimental study with a total of 70 patients who had undergone breast surgery (35 in the experimental group and 35 in the control group). Patients in the control group received only analgesic treatment, whereas those in the experimental group received foot massage in addition to analgesic treatment. Patients received the first dose of analgesics during surgery. As soon as patients came from the operating room, they were evaluated for pain severity. Patients whose pain severity scored ≥4 according to the Short-Form McGill Pain Questionnaire were accepted into the study. In the experimental group, pain and vital signs (arterial blood pressure, pulse, and respiration) were evaluated before foot massage at the time patients complained about pain (time 0) and then 5, 30, 60, 90, and 120 minutes after foot massage. In the control group, pain and vital signs were also evaluated when the patients complained about pain (time 0) and again at 5, 30, 60, 90, and 120 minutes, in sync with the times when foot massage was completed in the experimental group. A patient information form was used to collect descriptive characteristics data of the patients, and the Short-Form McGill Pain Questionnaire was used to determine pain severity. Data were analyzed for frequencies, mean, standard deviation, chi-square, Student t, Pillai trace, and Bonferroni test. The results of the statistical analyses showed that patients in the experimental group experienced significantly less pain (p ≤ .001). Especially notable, patients in the experimental group showed a decrease in all vital signs 5 minutes after foot massage, but patients in the control group showed increases in vital signs except for heart rate at 5 minutes. The data obtained showed that foot massage in breast surgery patients was
Psychometric Study of the Pain Drawing.
Trahan, Lisa H; Cox-Martin, Emily; Johnson, Carrie E; Dougherty, Patrick M; Yu, Jun; Feng, Lei; Cook, Christina; Novy, Diane M
2017-12-01
The objectives of the study were to (1) assess the extent to which interrater reliability of pain drawing location and dispersion scoring methods are similar across pain disciplines in a sample of patients with cancer treatment-induced neuropathic pain ( N = 56) and (2) investigate indicators of validity of the pain drawing in this unique sample. Patients undergoing cancer therapy completed the Brief Pain Inventory Body Map, the MD Anderson Symptom Inventory, and the McGill Pain Questionnaire. Intraclass correlation coefficients among medical and psychology professionals ranged from .93-.99. Correlations between pain drawing score and symptom burden severity ranged from .29-.39; correlations between pain drawing score and symptom burden interference ranged from .28-.34. Patients who endorsed pain in the hands and feet more often described their pain as electric, numb, and shooting than patients without pain in the hands and feet. They also endorsed significantly more descriptors of neuropathic pain. Results suggest a similar understanding among members of a multidisciplinary pain team as to the location and dispersion of pain as represented by patients' pain drawings. In addition, pain drawing scores were related to symptom burden severity and interference and descriptors of neuropathic pain in expected ways.
Chronic pain: One year prevalence and associated characteristics (the HUNT pain study).
Landmark, Tormod; Romundstad, Pål; Dale, Ola; Borchgrevink, Petter C; Vatten, Lars; Kaasa, Stein
2017-12-29
Background The reported prevalence of chronic pain ranges from 11% to 64%, and although consistently high, the calculated economic burden estimates also vary widely between studies. There is no standard way of classifying chronic pain. We have repeated measurements of pain in a longitudinal population study to improve validity ofthe case ascertainment. In this paper, associations between chronic pain and demographic characteristics, self reported health and functioning, work Incapacity and health care use were investigated in a sample from the general Norwegian population. Methods A random sample of 6419 participants from a population study (the HUNT 3 Study) was invited to report pain every three months during a 12 month period. Chronic pain was defined as moderate pain or more (on the SF-8 verbal rating scale) in at least three out of five consecutive measurements. Self reported health and functioning was measured by seven of the eight subscales on the SF-8 health survey (bodily pain was excluded). Health care utilisation during the past 12 months was measured by self report, and included seeing a general practitioner, seeing a medical specialist and seeing other therapists. The survey data was combined with information on income, education, disability pension awards and unemployment by Statistics Norway, which provided data from the National Education database (NUDB) and the Norwegian Labour and Welfare Administration (NAV). Results The total prevalence of chronic pain was 36% (95% CI34-38) among women and 25% (95% CI 22-26) among men. The prevalence increased with age, was higher among people with high BMI, and in people with low income and low educational level. Smoking was also associated with a higher prevalence of chronic pain. Subjects in the chronic pain group had a self-reported health and functioning in the range of 1-2.5 standard deviations below that of those without chronic pain. Among the chronic pain group 52% (95% CI 49-55), of participants
Rohe, Benjamin G; Carter, Ronald; Thompson, William R; Duncan, Randall L; Cooper, Carlton R
2015-04-01
Neck pain presents a tremendous physical and financial burden. This study compared the efficacy of the complementary and alternative medical treatments of integrative muscular movement technique (IMMT) and Swedish massage on neck pain in women of occupation age, the largest demographic group with neck pain. A total of 38 women were assigned to IMMT (n=28) or Swedish massage (n=10) in a blinded manner. Both groups received eight 30-minute treatments over 4 weeks. Cervical range of motion (ROM) in flexion, extension, sidebending, and rotation was measured before and after treatment. Each patient's pain was assessed by using an analogue pain scale of 0-10. Compared with the Swedish massage group, patients receiving IMMT experienced a significant increase in ROM in cervical flexion (p<0.001), extension (p<0.001), sidebending (p<0.05), and rotation (p<0.001). Absolute change in pain for IMMT was -1.75 units compared with -0.3 units for Swedish massage (p<0.05). Patients receiving the IMMT demonstrated significantly improved cervical ROM in every movement measured compared with Swedish massage. Inclusion of the IMMT in a treatment regimen for chronic neck pain may lead to decreased pain and increased cervical ROM. These positive effects of the IMMT intervention may have a role in enhancing functional outcomes in patients with neck pain.
Jacobs, Jesse V.; Yaguchi, Chie; Kaida, Chizuru; Irei, Mariko; Naka, Masami; Henry, Sharon M.; Fujiwara, Katsuo
2011-01-01
It is becoming increasingly evident that people with chronic, recurrent low back pain (LBP) exhibit changes in cerebrocortical activity that associate with altered postural coordination, suggesting a need for a better understanding of how the experience of LBP alters postural coordination and cerebrocortical activity. To characterize changes in postural coordination and pre-movement cerebrocortical activity related to the experience of acutely induced LBP, 14 healthy participants with no history of LBP performed sit-to-stand movements in 3 sequential conditions: (1) without experimentally induced LBP; NoPain1, (2) with movement-associated LBP induced by electrocutaneous stimulation; Pain, and (3) again without induced LBP; NoPain2. The Pain condition elicited altered muscle activation and redistributed forces under the seat and feet prior to movement, decreased peak vertical force exerted under the feet during weight transfer, longer movement times, as well as decreased and earlier peak hip extension. Stepwise regression models demonstrated that electroencephalographic amplitudes of contingent negative variation during the Pain condition significantly correlated with the participants’ change in sit-to-stand measures between the NoPain1 and Pain conditions, as well as with the subsequent difference in sit-to-stand measures between the NoPain1 and NoPain2 conditions. The results, therefore, identify the contingent negative variation as a correlate for the extent of an individual’s LBP-related movement modifications and to the subsequent change in movement patterns from before to after the experience of acutely induced LBP, thereby providing a direction for future studies aimed to understand the neural mechanisms underlying the development of altered movement patterns with LBP. PMID:21952791
Profiles of Urine Drug Test in Clinical Pain Patients vs Pain Research Study Subjects.
Lee, Cheng-ting; Vo, Trang T; Cohen, Abigail S; Ahmed, Shihab; Zhang, Yi; Mao, Jianren; Chen, Lucy
2016-04-01
To examine similarities and differences in urine drug test (UDT) results in clinical pain patients and pain subjects participating in pain research studies. An observational study with retrospective chart review and data analysis. We analyzed 1,874 UDT results obtained from 1) clinical pain patients (Clinical Group; n = 1,529) and 2) pain subjects consented to participate in pain research studies (Research Group; n = 345). Since several medications such as opioids used in pain management are drugs of abuse (DOA) and can result in a positive UDT, we specifically identified those cases of positive UDT due to nonprescribed DOA and designated these cases as positive UDT with DOA (PUD). We found that 1) there was a higher rate of PUD in clinical pain patients (41.3%) than in pain research study subjects (14.8%); 2) although subjects in the Research Group were informed ahead of time that UDT will be conducted as a screening test, a substantial number (14.8%) of pain research study subjects still showed PUD; 3) there were different types of DOA between clinical pain patients (cannabinoids as the top DOA) and research study subjects (cocaine as the top DOA); and 4) a common factor associated with PUD was opioid therapy in both Clinical Group and Research Group. These results support previous findings that PUD is a common finding in clinical pain patients, particularly in those prescribed opioid therapy, and we suggest that UDT be used as routine screening testing in pain research studies. © 2015 American Academy of Pain Medicine. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.
Ingvar, M
1999-01-01
Functional neuroimaging has fundamentally changed our knowledge about the cerebral representation of pain. For the first time it has been possible to delineate the functional anatomy of different aspects of pain in the medial and lateral pain systems in the brain. The rapid developments in imaging methods over the past years have led to a consensus in the description of the central pain responses between different studies and also to a definition of a central pain matrix with specialized subfunctions in man. In the near future we will see studies where a systems perspective allows for a better understanding of the regulatory mechanisms in the higher-order frontal and parietal cortices. Also, pending the development of experimental paradigms, the functional anatomy of the emotional aspects of pain will become better known. PMID:10466155
Pain anticipation: an activation likelihood estimation meta-analysis of brain imaging studies.
Palermo, Sara; Benedetti, Fabrizio; Costa, Tommaso; Amanzio, Martina
2015-05-01
The anticipation of pain has been investigated in a variety of brain imaging studies. Importantly, today there is no clear overall picture of the areas that are involved in different studies and the exact role of these regions in pain expectation remains especially unexploited. To address this issue, we used activation likelihood estimation meta-analysis to analyze pain anticipation in several neuroimaging studies. A total of 19 functional magnetic resonance imaging were included in the analysis to search for the cortical areas involved in pain anticipation in human experimental models. During anticipation, activated foci were found in the dorsolateral prefrontal, midcingulate and anterior insula cortices, medial and inferior frontal gyri, inferior parietal lobule, middle and superior temporal gyrus, thalamus, and caudate. Deactivated foci were found in the anterior cingulate, superior frontal gyrus, parahippocampal gyrus and in the claustrum. The results of the meta-analytic connectivity analysis provide an overall view of the brain responses triggered by the anticipation of a noxious stimulus. Such a highly distributed perceptual set of self-regulation may prime brain regions to process information where emotion, action and perception as well as their related subcategories play a central role. Not only do these findings provide important information on the neural events when anticipating pain, but also they may give a perspective into nocebo responses, whereby negative expectations may lead to pain worsening. © 2014 Wiley Periodicals, Inc.
A prospective study of acceptance of pain and patient functioning with chronic pain.
McCracken, Lance M; Eccleston, Christopher
2005-11-01
Acceptance of chronic pain is emerging as an important concept in understanding ways that chronic pain sufferers can remain engaged with valued aspects of life. Recent studies have relied heavily on cross-sectional investigations at a single time point. The present study sought to prospectively investigate relations between acceptance of chronic pain and patient functioning. A sample of adults referred for interdisciplinary treatment of severe and disabling chronic pain was assessed twice, an average of 3.9 months apart. Results showed that pain and acceptance were largely unrelated. Pain at Time 2 was weakly related to measures of functioning at Time 2. On the other hand, acceptance at Time 1 was consistently related to patient functioning at Time 2. Those patients who reported greater acceptance at Time 1 reported better emotional, social, and physical functioning, less medication consumption, and better work status at Time 2. These data suggest that willingness to have pain, and to engage in activity regardless of pain, can lead to healthy functioning for patients with chronic pain. Treatment outcome and process studies may demonstrate the potential for acceptance-based clinical methods for chronic pain management.
Esteban González, Pedro; Novoa, Nuria M; Varela, Gonzalo
2015-12-01
The patient's position during an axillary thoracotomy can cause postoperative pain and decrease mobility of the ipsilateral shoulder. In this study, we assessed whether the implementation of a standardized analgesia program using transcutaneous electrical nerve stimulation (TENS) decreases local pain and improves ipsilateral shoulder mobility. Randomized, single-blind, single-center clinical trial of 50 patients who had undergone anatomical lung resection via axillary muscle-sparing thoracotomy. Patients were treated with TENS devices for 30 minutes every 8 hours, beginning on postoperative day 1. Pain and mobility of the affected limb were recorded at the same time on postoperative days 1 through 3. A visual analogue scale was used for pain assessment and shoulder mobility was assessed with a goniometer. Results were compared using a non-parametric test. Twenty-five patients were randomized to each group. Mean age of the control group was 62.7±9.3 years and 63.4±10.2 years in the experimental group. Shoulder mobility parameters were similar in both groups on all postoperative days. However, pain during flexion significantly decreased on day 2 (P=.03) and day 3 (P=.04) in the experimental group. The use of TENS decreases pain from shoulder flexion in patients undergoing axillary thoracotomy for pulmonary resection. Copyright © 2014 SEPAR. Published by Elsevier Espana. All rights reserved.
Dimov, Luiz Fabio; Toniolo, Elaine Flamia; Alonso-Matielo, Heloísa; de Andrade, Daniel Ciampi; Garcia-Larrea, Luis; Ballester, Gerson; Teixeira, Manoel Jacobsen; Dale, Camila Squarzoni
2018-07-02
Cortical electrical stimulation (CES) has shown to be an effective therapeutic alternative for neuropathic pain refractory to pharmacological treatment. The primary motor cortex(M1) was the main cortical target used in the vast majority of both invasive and non-invasive studies. Despite positive results M1-based approaches still fail to relieve pain in a significant proportion of individuals. It has been advocated that the direct stimulation of cortical areas directly implicated in the central integration of pain could increase the efficacy of analgesic brain stimulation. Here, we evaluated the behavioral effects of electrical stimulation of the insular cortex (ESI) on pain sensitivity in an experimental rat model of peripheral neuropathy, and have described the pathways involved. Animals underwent chronic constriction of the sciatic nerve in the right hind limb and had concentric electrodes implanted in the posterior dysranular insular cortex. Mechanical nociception responses were evaluated before and at the end of a 15-min session of ESI (60Hz, 210μs, 1V). ESI reversed mechanical hypersensitivity in the paw contralateral to the brain hemisphere stimulated, without inducing motor impairment in the open-field test. Pharmacological blockade of μ-opioid (MOR) or type 1-cannabinoid receptors (CB1R) abolished ESI-induced antinociceptive effects. Evaluation of CB1R and MOR spatial expression demonstrated differential modulation of CB1R and MOR in the periaqueductal gray matter (PAG) of ESI-treated rats in sub-areas involved in pain processing/modulation. These results indicate that ESI induces antinociception by functionally modulating opioid and cannabinoid systems in the PAG pain circuitry in rats with experimentally induced neuropathic pain. Copyright © 2017 Elsevier B.V. All rights reserved.
Grimby-Ekman, Anna; Andersson, Eva M; Hagberg, Mats
2009-01-01
Background In the literature there are discussions on the choice of outcome and the need for more longitudinal studies of musculoskeletal disorders. The general aim of this longitudinal study was to analyze musculoskeletal neck pain, in a group of young adults. Specific aims were to determine whether psychosocial factors, computer use, high work/study demands, and lifestyle are long-term or short-term factors for musculoskeletal neck pain, and whether these factors are important for developing or ongoing musculoskeletal neck pain. Methods Three regression models were used to analyze the different outcomes. Pain at present was analyzed with a marginal logistic model, for number of years with pain a Poisson regression model was used and for developing and ongoing pain a logistic model was used. Presented results are odds ratios and proportion ratios (logistic models) and rate ratios (Poisson model). The material consisted of web-based questionnaires answered by 1204 Swedish university students from a prospective cohort recruited in 2002. Results Perceived stress was a risk factor for pain at present (PR = 1.6), for developing pain (PR = 1.7) and for number of years with pain (RR = 1.3). High work/study demands was associated with pain at present (PR = 1.6); and with number of years with pain when the demands negatively affect home life (RR = 1.3). Computer use pattern (number of times/week with a computer session ≥ 4 h, without break) was a risk factor for developing pain (PR = 1.7), but also associated with pain at present (PR = 1.4) and number of years with pain (RR = 1.2). Among life style factors smoking (PR = 1.8) was found to be associated to pain at present. The difference between men and women in prevalence of musculoskeletal pain was confirmed in this study. It was smallest for the outcome ongoing pain (PR = 1.4) compared to pain at present (PR = 2.4) and developing pain (PR = 2.5). Conclusion By using different regression models different aspects of neck
Grimby-Ekman, Anna; Andersson, Eva M; Hagberg, Mats
2009-06-19
In the literature there are discussions on the choice of outcome and the need for more longitudinal studies of musculoskeletal disorders. The general aim of this longitudinal study was to analyze musculoskeletal neck pain, in a group of young adults. Specific aims were to determine whether psychosocial factors, computer use, high work/study demands, and lifestyle are long-term or short-term factors for musculoskeletal neck pain, and whether these factors are important for developing or ongoing musculoskeletal neck pain. Three regression models were used to analyze the different outcomes. Pain at present was analyzed with a marginal logistic model, for number of years with pain a Poisson regression model was used and for developing and ongoing pain a logistic model was used. Presented results are odds ratios and proportion ratios (logistic models) and rate ratios (Poisson model). The material consisted of web-based questionnaires answered by 1204 Swedish university students from a prospective cohort recruited in 2002. Perceived stress was a risk factor for pain at present (PR = 1.6), for developing pain (PR = 1.7) and for number of years with pain (RR = 1.3). High work/study demands was associated with pain at present (PR = 1.6); and with number of years with pain when the demands negatively affect home life (RR = 1.3). Computer use pattern (number of times/week with a computer session > or = 4 h, without break) was a risk factor for developing pain (PR = 1.7), but also associated with pain at present (PR = 1.4) and number of years with pain (RR = 1.2). Among life style factors smoking (PR = 1.8) was found to be associated to pain at present. The difference between men and women in prevalence of musculoskeletal pain was confirmed in this study. It was smallest for the outcome ongoing pain (PR = 1.4) compared to pain at present (PR = 2.4) and developing pain (PR = 2.5). By using different regression models different aspects of neck pain pattern could be addressed and
Lima, Vicente Pinheiro; de Alkmim Moreira Nunes, Rodolfo; da Silva, Jurandir Baptista; Paz, Gabriel Andrade; Jesus, Marco; de Castro, Juliana Brandão Pinto; Dantas, Estélio Henrique Martin; de Souza Vale, Rodrigo Gomes
2018-03-02
The aim of this study was to evaluate the effects of a 10-week core and mobility training program on pain perception and low back disability score in professors, students and employees of a university. Twenty-four individuals of a university who previously reported pain and low back disability were randomly assigned to an experimental group (EG; n= 8) that received 2 weekly sessions of 50 minutes of core and mobility training for 10 weeks; or to a control group (CG; n= 16). Both groups received a guideline to adopt ergonomic postures during work and activities of daily living. The visual analog pain scale (VAS) and the Roland-Morris questionnaire (RMQ) were applied pre and post intervention. Significant reductions in the pain intensity perception (p= 0.014) and low back functional disability (p= 0.011) were noted in the EG pre and post measures. However, no significant difference was observed in the CG. Thus, there was a significant difference between the EG and the CG in the post-intervention measures (p= 0.001). Core and mobility training and home-ergonomic instructions were effective to reduce the pain intensity perception and low back functional disability in the EG.
2013-01-01
Background Several chronic pain populations have demonstrated decreased conditioned pain modulation (CPM). However there is still a need to investigate the stability of CPM paradigms before the measure can be recommended for implementation. The purpose of the present study was to assess whether shoulder pain intensity and gender influence CPM stability within and between sessions. Methods This study examined two different musculoskeletal pain models, clinical shoulder pain and an experimental model of shoulder pain induced with eccentric exercise in healthy participants. Patients in the clinical cohort (N = 134) were tested before surgery and reassessed 3 months post-surgery. The healthy cohort (N = 190) was examined before inducing pain at the shoulder, and 48 and 96 hours later. Results Our results provide evidence that 1) stability of inhibition is not related to changes in pain intensity, and 2) there are sex differences for CPM stability within and between days. Conclusions Fluctuation of pain intensity did not significantly influence CPM stability. Overall, the more stable situations for CPM were females from the clinical cohort and males from the healthy cohort. PMID:23758907
Individual Differences in Pain: Understanding the Mosaic that Makes Pain Personal
Fillingim, Roger B.
2016-01-01
The experience of pain is characterized by tremendous inter-individual variability. Multiple biological and psychosocial variables contribute to these individual differences in pain, including demographic variables, genetic factors, and psychosocial processes. For example, sex, age and ethnic group differences in the prevalence of chronic pain conditions have been widely reported. Moreover, these demographic factors have been associated with responses to experimentally-induced pain. Similarly, both genetic and psychosocial factors contribute to clinical and experimental pain responses. Importantly, these different biopsychosocial influences interact with each other in complex ways to sculpt the experience of pain. Some genetic associations with pain have been found to vary across sex and ethnic group. Moreover, genetic factors also interact with psychosocial factors, including stress and pain catastrophizing, to influence pain. The individual and combined influences of these biological and psychosocial variables results in a unique mosaic of factors that contributes pain in each individual. Understanding these mosaics is critically important in order to provide optimal pain treatment, and future research to further elucidate the nature of these biopsychosocial interactions is needed in order to provide more informed and personalized pain care. PMID:27902569
Parenting in the context of chronic pain: A controlled study of parents with chronic pain
Wilson, Anna C.; Fales, Jessica L.
2014-01-01
Objectives This study aims to describe what adults with chronic pain experience in their role as parents, utilizing quantitative and qualitative methods. The first aim is to compare parents with chronic pain to parents without chronic pain on perceptions of their adolescent’s pain, parental response to pain, and catastrophizing beliefs about pain. The study also examined predictors of parental protective behaviors, and examined whether these associations differed by study group. Methods Parents with chronic pain (n=58) and parents without chronic pain (n=72) participated, and completed questionnaire measures of pain characteristics and pain interference, as well as measures of parental catastrophizing and protective pain responses. Parents with chronic pain also completed a structured interview about their experience of being a parent. Interview responses were videotaped and subsequently coded for content. Results Compared to controls, parents with chronic pain endorsed more pain in their adolescents, and were more likely to catastrophize about their adolescent’s pain and respond with protective behaviors. Parent’s own pain interference and the perception of higher pain in their adolescent was associated with increased protective parenting in the chronic pain group. Qualitative coding revealed a number of areas of common impact of chronic pain on parenting. Discussion Chronic pain impacts everyday parenting activities and emotions, and impacts pain-specific parent responses that are known to be related to increased pain and pain catastrophizing in children and adolescents. Parents with chronic pain might benefit from interventions that address potential parenting difficulties, and might improve outcomes for their children. PMID:25232862
Prediction of pain in orthodontic patients based on preoperative pain assessment
Zheng, Baoyu; Ren, Manman; Lin, Feiou; Yao, Linjie
2016-01-01
Aim To investigate whether pretreatment assessment of experimental pain can predict the level of pain after archwire placement. Methods One hundred and twenty-one general university students seeking orthodontic treatment were enrolled in this study. A cold pressor test was performed to estimate the pain tolerance of subjects before treatment. Self-reported pain intensity was calculated using a 10 cm visual analog scale during the 7 days after treatment. The relationship between pain tolerance and orthodontic pain was analyzed using Spearman’s correlation analysis. Results The maximum mean level of pain intensity occurred at 24 hours after bonding (53.31±16.13) and fell to normal levels at day 7. Spearman’s correlation analysis found a moderate positive association between preoperative pain tolerance and self-reported pain after archwire placement (P<0.01). There was no significant difference in pain intensity between male and female patients at any time point (P>0.05). Conclusion A simple and noninvasive preoperative sensory test (the cold pressor test) was useful in predicting the risk of developing unbearable pain in patients after archwire placement. Self-reported pain after archwire placement decreased as individual pain tolerance increased. PMID:27042019
Trojan, Jörg; Kleinböhl, Dieter; Stolle, Annette M; Andersen, Ole K; Hölzl, Rupert; Arendt-Nielsen, Lars
2009-03-01
Distortions of the body image have been repeatedly reported for various clinical conditions, but direct experimental analyses of the perceptual changes involved are still scarce. In addition, most experimental studies rely on cerebral activation patterns to assess neuroplastic changes in central representation, although the relationship between cerebral topography and the topology of the perceptual space is not clear. This study examines whether the direct psychophysical mapping approach we introduced recently (Trojan et al., Brain Res 2006;1120:106-113) is capable of tracking perceptual distortions in the somatotopic representation of heat-pain stimuli. Eleven healthy participants indicated the perceived positions of CO(2) laser stimuli, repetitively presented to the dorsal forearm, with a 3D tracking system in two consecutive sessions, separated by the topical application of capsaicin cream. In line with earlier reports, we expected that the resulting individual perceptual maps (i.e., one-dimensional projections of the perceived positions onto the forearm surface) would be subject to modulation through the altered sensory input, to be measured in terms of altered topological parameters. We found that the topology and metrics of the somatotopic representation were well preserved in the second session, but that the perceptual map was compressed to a smaller range in 9 out of 11 participants. By providing dimensional measures of perceptual representations, perceptual maps constitute an independent, genuinely psychological complement to the topography of cortical activations measured with neuroimaging methods. In addition, we expect them to be useful in diagnosing pathological changes in body perception accompanying chronic pain and other disorders.
The effects of music therapy on pain in patients with neuropathic pain.
Korhan, Esra Akın; Uyar, Meltem; Eyigör, Can; Hakverdioğlu Yönt, Gülendam; Çelik, Serkan; Khorshıd, Leyla
2014-03-01
The aim of this study was to investigate the effect of relaxing music on pain intensity in patients with neuropathic pain. A quasi-experimental study, repeated measures design was used. Thirty patients, aged 18-70 years, with neuropathic pain and hospitalized in an Algology clinic were identified as a convenience sample. Participants received 60 minutes of music therapy. Classical Turkish music was played to patients using a media player (MP3) and headphones. Participants had pain scores taken immediately before the intervention and at the 30th and 60th minutes of the intervention. Data were collected over a 6-month period in 2012. The patients' mean pain intensity scores were reduced by music, and that decrease was progressive over the 30th and 60th minutes of the intervention, indicating a cumulative dose effect. The results of this study implied that the inclusion of music therapy in the routine care of patients with neuropathic pain could provide nurses with an effective practice for reducing patients' pain intensity. Copyright © 2014 American Society for Pain Management Nursing. Published by Elsevier Inc. All rights reserved.
Is TENS purely a placebo effect? A controlled study on chronic low back pain.
Marchand, S; Charest, J; Li, J; Chenard, J R; Lavignolle, B; Laurencelle, L
1993-07-01
Although high-frequency low-intensity transcutaneous electric nerve stimulation (TENS) has been extensively used to relieve low back pain, experimental studies of its effectiveness have yielded contradictory findings mainly due to methodological problems in pain evaluation and placebo control. In the present study, separate visual analog scales (VAS) were used to measure the sensory-discriminative and motivational-affective components of low back pain. Forty-two subjects were randomly assigned to 1 of 3 groups: TENS, placebo-TENS, and no treatment (control). In order to measure the short-term effect of TENS, VAS pain ratings were taken before and after each treatment session. Also, to measure long-term effects, patients rated their pain at home every 2 h throughout a 3-day period before and 1 week, 3 months and 6 months after the treatment sessions. In comparing the pain evaluations made immediately before and after each treatment session, TENS and placebo-TENS significantly reduced both the intensity and unpleasantness of chronic low back pain. TENS was significantly more efficient than placebo-TENS in reducing pain intensity but not pain unpleasantness. TENS also produced a significant additive effect over repetitive treatment sessions for pain intensity and relative pain unpleasantness. This additive effect was not found for placebo-TENS. When evaluated at home, pain intensity was significantly reduced more by TENS than placebo-TENS 1 week after the end of treatment, but not 3 months and 6 months later. At home evaluation of pain unpleasantness in the TENS group was never different from the placebo-TENS group.(ABSTRACT TRUNCATED AT 250 WORDS)
Muceli, Silvia; Falla, Deborah
2014-01-01
Muscle pain induces a complex reorganization of the motor strategy which cannot be fully explained by current theories. We tested the hypothesis that the neural control of muscles during reaching in the presence of nociceptive input is determined by a reorganization of muscle synergies with respect to control conditions. Muscle pain was induced by injection of hypertonic saline into the anterior deltoid muscle of eight men. Electromyographic (EMG) signals were recorded from 12 upper limb muscles as subjects performed a reaching task before (baseline) and after the injection of hypertonic (pain) saline, and after the pain sensation vanished. The EMG envelopes were factorized in muscle synergies, and activation signals extracted for each condition. Nociceptive stimulation resulted in a complex muscle reorganization without changes in the kinematic output. The anterior deltoid muscle activity decreased in all subjects while the changes in other muscles were subject specific. Three synergies sufficed to describe the EMG patterns in each condition, suggesting that reaching movements remain modular in the presence of experimental pain. Muscle reorganization in all subjects was accompanied by a change in the activation signals compatible with a change in the central drive to muscles. One, two or three synergies were shared between the baseline and painful conditions, depending on the subject. These results indicate that nociceptive stimulation may induce a reorganization of modular control in reaching. We speculate that such reorganization may be due to the recruitment of synergies specific to the painful condition. PMID:24453279
Ballard, Ariane; Le May, Sylvie; Khadra, Christelle; Lachance Fiola, Jacinthe; Charette, Sylvie; Charest, Marie-Claude; Gagnon, Hélène; Bailey, Benoit; Villeneuve, Edith; Tsimicalis, Argerie
2017-12-01
To assess the feasibility, usefulness, and acceptability of using distraction kits, tailored to age, for procedural pain management of young children visiting the emergency department and requiring a needle-related procedure. A pre-experimental design was piloted. A kit, tailored to age (infants-toddlers: 3 months-2 years; preschoolers: 3-5 years), was provided to parents before their child's needle-related procedure. Data was collected to assess feasibility, usefulness, and acceptability of the kits by parents and nurses. Pain was measured pre-, peri-, and postprocedure using the Face, Legs, Activity, Cry, Consolability scale. A total of 25 infants and toddlers (mean age: 1.4 ± .7 years) and 25 preschoolers (mean age: 4.0 ± .9) participated in the study. Parents and nurses considered the kits useful and acceptable for distraction in the emergency department, especially in the postprocedural period. Addition of more animated and interactive toys to the kits was suggested. In the infants-toddlers group, mean pain scores were 1.6 ± 2.5 preprocedure, 7.1 ± 3.0 periprocedure, and 2.5 ± 2.5 postprocedure. In the preschoolers group, mean pain scores were 1.6 ± 3.0 preprocedure, 4.8 ± 3.4 periprocedure, and 2.0 ± 3.2 postprocedure. Distraction kits were deemed useful and acceptable by parents and emergency nurses. They are an interesting nonpharmacologic option for nurses to distract children, giving them a sense of control over their pain and improving their hospital experience. Future research should address the feasibility of distraction kits for a broader population of patients and a variety of painful procedures. Copyright © 2017 American Society for Pain Management Nursing. Published by Elsevier Inc. All rights reserved.
The Effect of Positive Affect on the Memory of Pain.
Bąbel, Przemysław
2017-06-01
The aim of the study was to assess the accuracy of the memory of experimentally induced pain and the affect that accompanies experimentally induced pain. Sixty-two healthy female volunteers participated in the study. In the first phase of the study, the participants received three pain stimuli and rated pain intensity, pain unpleasantness, state anxiety, and their positive and negative affect. About a month later, in the second phase of the study, the participants were asked to rate the pain intensity, pain unpleasantness, state anxiety, and the emotions they had felt during the first phase of the study. Both recalled pain intensity and recalled pain unpleasantness were found to be underestimated. Although the positive affect that accompanied pain was remembered accurately, recalled negative affect was overestimated and recalled state anxiety was underestimated. Experienced pain, recalled state anxiety, and recalled positive affect accounted for 44% of the total variance in predicting recalled pain intensity and 61% of the total variance in predicting recalled pain unpleasantness. Together with recent research findings on the memory of other types of pain, the present study supports the idea that pain is accompanied by positive as well as negative emotions, and that positive affect influences the memory of pain. Copyright © 2017 American Society for Pain Management Nursing. Published by Elsevier Inc. All rights reserved.
The language of pain: A short study
Rathnam, Arun; Madan, Nidhi; Madan, Neeti
2010-01-01
Background: Pain perception is a very controversial topic in child patients. It is affected by various factors such as fear, anxiety, previous experiences, parental factors, and pain threshold. The communication of such pain by the child to the parent is also very confusing with children having rudimentary and developing communication skills. A study to evaluate the pain perception of children and the parental understanding of the children's pain would be helpful in this scenario. The effect on behavior due to pain is also attempted in this particular study. Materials and Methods: A cross-sectional study of 100 children aged between 5-13 years accompanied by either parent was performed. Data collection was done with the help of questionnaires, which assessed the parental understanding of the child's pain. Pain perception recording was done with the Visual Analog Scale of Faces (VASOF). The behavior of the child was noted using the Frankl's behavior rating scale. Data was collated and statistical analysis was performed using the SPSS (version 10) software. Results and conclusion: The results show that parental factors such as education, work culture, influence parental understanding of pain. VASOF proves to be a reliable tool for pain perception in children. Behavior of the child shows a positive correlation to pain perception. PMID:22114404
Zheng, Zhen; Wang, Kelun; Yao, Dongyuan; Xue, Charlie C L; Arendt-Nielsen, Lars
2014-05-01
This study investigated the relationship between pain sensitivity, adaptability, and potency of endogenous pain inhibition, including conditioned pain modulation (CPM) and local pain inhibition. Forty-one healthy volunteers (20 male, 21 female) received conditioning stimulation (CS) over 2 sessions in a random order: tonic heat pain (46 °C) on the right leg for 7 minutes and cold pressor pain (1 °C to 4 °C) on the left hand for 5 minutes. Participants rated the intensity of pain continuously using a 0 to 10 electronic visual analogue scale. The primary outcome measures were pressure pain thresholds (PPT) measured at the heterotopic and homotopic location to the CS sites before, during, and 20 minutes after CS. Two groups of participants, pain adaptive and pain nonadaptive, were identified based on their response to pain in the cold pressor test. Pain-adaptive participants showed a pain reduction between peak pain and pain at end of the test by at least 2 of 10 (n=16); whereas the pain-nonadaptive participants reported unchanged peak pain during 5-minute CS (n=25). Heterotopic PPTs during the CS did not differ between the 2 groups. However, increased homotopic PPTs measured 20 minutes after CS correlated with the amount of pain reduction during CS. These results suggest that individual sensitivity and adaptability to pain does not correlate with the potency of CPM. Adaptability to pain is associated with longer-lasting local pain inhibition. Copyright © 2014 International Association for the Study of Pain. Published by Elsevier B.V. All rights reserved.
Chen, Hong; Slade, Gary; Lim, Pei Feng; Miller, Vanessa; Maixner, William; Diatchenko, Luda
2012-01-01
The multiple bodily pain conditions in temporomandibular disorders (TMD) have been associated with generalized alterations in pain processing. The purpose of this study was to examine the relationship between the presence of widespread body palpation tenderness (WPT) and the likelihood of multiple comorbid pain conditions in TMD patients and controls. This case-control study was conducted in 76 TMD subjects with WPT, 83 TMD subjects without WPT, and 181 non-TMD matched control subjects. The study population was also characterized for clinical pain, experimental pain sensitivity, and related psychological phenotypes. Results showed that (1) TMD subjects reported an average of 1.7 comorbid pain conditions compared to 0.3 reported by the control subjects (p<0.001); (2) Compared to control subjects, the odds ratio (OR) for multiple comorbid pain conditions is higher for TMD subjects with WPT [OR 8.4 (95% CI 3.1–22.8) for TMD with WPT versus OR 3.3 (95% CI 1.3–8.4) for TMD without WPT]; (3) TMD subjects with WPT presented with reduced pressure pain thresholds (PPTs) in both cranial and extra-cranial regions compared to TMD subjects without WPT; and (4) TMD subjects with WPT reported increased somatic symptoms. These findings suggest that pain assessment outside of the orofacial region may prove valuable for the classification, diagnosis, and management of TMD patients. PMID:23031401
Dubois, Jean-Daniel; Abboud, Jacques; St-Pierre, Charles; Piché, Mathieu; Descarreaux, Martin
2014-08-01
Patients with chronic low back pain exhibit characteristics such as clinical pain, psychological symptoms and neuromuscular adaptations. The purpose of this study was to determine the independent contribution of clinical pain, psychological factors and neuromuscular adaptations to disability in patients with chronic low back pain. Clinical pain intensity, pain catastrophizing, fear-avoidance beliefs, anxiety, neuromuscular adaptations to chronic pain and neuromuscular responses to experimental pain were assessed in 52 patients with chronic low back pain. Lumbar muscle electromyographic activity was assessed during a flexion-extension task (flexion relaxation phenomenon) to assess both chronic neuromuscular adaptations and neuromuscular responses to experimental pain during the task. Multiple regressions showed that independent predictors of disability included neuromuscular adaptations to chronic pain (β=0.25, p=0.006, sr(2)=0.06), neuromuscular responses to experimental pain (β=-0.24, p=0.011, sr(2)=0.05), clinical pain intensity (β=0.28, p=0.002, sr(2)=0.08) and psychological factors (β=0.58, p<0.001, sr(2)=0.32). Together, these predictors accounted for 65% of variance in disability (R(2)=0.65 p<0.001). The current investigation revealed that neuromuscular adaptations are independent from clinical pain intensity and psychological factors, and contribute to inter-individual differences in patients' disability. This suggests that disability, in chronic low back pain patients, is determined by a combination of factors, including clinical pain, psychological factors and neuromuscular adaptations. Copyright © 2014 Elsevier Ltd. All rights reserved.
The role of executive functioning in children's attentional pain control: an experimental analysis.
Verhoeven, Katrien; Dick, Bruce; Eccleston, Christopher; Goubert, Liesbet; Crombez, Geert
2014-02-01
Directing attention away from pain is often used in children's pain treatment programs to control pain. However, empirical evidence concerning its effectiveness is inconclusive. We therefore sought to understand other influencing factors, including executive function and its role in the pain experience. This study investigates the role of executive functioning in the effectiveness of distraction. School children (n=164) completed executive functioning tasks (inhibition, switching, and working memory) and performed a cold-pressor task. One half of the children simultaneously performed a distracting tone-detection task; the other half did not. Results showed that participants in the distraction group were engaged in the distraction task and were reported to pay significantly less attention to pain than controls. Executive functioning influenced distraction task engagement. More specifically, participants with good inhibition and working memory abilities performed the distraction task better; participants with good switching abilities reported having paid more attention to the distraction task. Furthermore, distraction was found to be ineffective in reducing pain intensity and affect. Executive functioning did not influence the effectiveness of distraction. However, a relationship was found between executive functioning and pain affect, indicating that participants with good inhibition and working memory abilities experienced the cold-pressor task as less stressful and unpleasant. Our findings suggest that distraction as a process for managing pain is complex. While it appears that executive function may play a role in adult distraction, in this study it did not direct attention away from pain. It may instead be involved in the overall pain experience. Copyright © 2013 International Association for the Study of Pain. Published by Elsevier B.V. All rights reserved.
Effect of music therapy on pain behaviors in rats with bone cancer pain.
Gao, Ji; Chen, Shaoqin; Lin, Suyong; Han, Hongjing
2016-01-01
To investigate the effects of music therapy on the pain behaviors and survival of rats with bone cancer pain and analyze the mediating mechanism of mitogen activated protein kinase (MAPK) signal transduction pathway. Male Wistar rats aged 5-8 weeks and weighing 160-200 g were collected. The rat models of colorectal cancer bone cancer pain was successfully established. Animals were divided into experimental and control group, each with 10 rats. The animals in the observation group were given Mozart K448 sonata, sound intensity of 60 db, played the sonata once every 1 hr in the daytime, stopped playing during the night, and this cycle was kept for 2 weeks. On the other hand, rats in the control group were kept under the same environment without music. Animals in the experimental group consumed more feed and gained significant weight in comparison to the control group. The tumor volume of the experimental group was significantly smaller than that of the control group (p<0.05). After 1-2 weeks of treatment, spontaneous foot withdrawal reflection caused by pain in the experimental group was significantly lower than that in the control group, heat pain threshold and free walking pain scoring in the experimental group were also significantly higher as compared with the control group (p<0.05). The expression of p38á and p38β in animals' spinal cord and dorsal root ganglion was significantly lower in the experimental group than in the control group (p< 0.05). Music therapy may improve the pain behaviors in rats with bone cancer pain, which might be related with low expression of p38á and p38β in the MAPK signal transduction pathway.
Sipilä, Reetta M.; Haasio, Lassi; Meretoja, Tuomo J.; Ripatti, Samuli; Estlander, Ann-Mari; Kalso, Eija A.
2017-01-01
Abstract The aim of this study was to identify clinical risk factors for unfavorable pain trajectories after breast cancer surgery, to better understand the association between pain expectation, psychological distress, and acute postoperative pain. This prospective study included 563 women treated for breast cancer. Psychological data included questionnaires for depressive symptoms and anxiety. Experimental pain tests for heat and cold were performed before surgery. The amount of oxycodone needed for satisfactory pain relief after surgery was recorded. Pain intensity in the area of operation before surgery and during the first postoperative week and expected intensity of postoperative pain were recorded using the Numerical Rating Scale (NRS 0-10). Pain trajectories were formed to describe both initial intensity (the intercept) and the direction of the pain path (the slope). Factors associated with higher initial pain intensity (the intercept) were the amount of oxycodone needed for adequate analgesia, psychological distress, type of axillary surgery, preoperative pain in the area of the operation, and expectation of postoperative pain. The higher the pain initially was, the faster it resolved over the week. Expectation of severe postoperative pain was associated with higher scores of both experimental and clinical pain intensity and psychological factors. The results confirm that acute pain after breast cancer surgery is a multidimensional phenomenon. Psychological distress, pain expectation, and the patients' report of preoperative pain in the area to be operated should be recognized before surgery. Patients having axillary clearance need more efficient analgesic approaches. PMID:28134654
Semrau, Jana; Hentschke, Christian; Buchmann, Jana; Meng, Karin; Vogel, Heiner; Faller, Hermann; Bork, Hartmut; Pfeifer, Klaus
2015-01-01
Improvement of the long-term effectiveness of multidisciplinary ortho-paedic rehabilitation (MOR) in the management of chronic non-specific low back pain (CLBP) remains a central issue for health care in Germany. We developed an interprofessional and interdisciplinary, biopsychosocial rehabilitation concept named "PASTOR" to promote self-management in adults with CLBP and compared its effectiveness with the current model of MOR. A multicentre quasi-experimental study with three measurement time points was implemented. 680 adults aged 18 to 65 with CLBP were assed for eligibil-ity in three inpatient rehabilitation centres in Germany. At first the effects of the MOR, with a total extent of 48 hours (control group), were assessed. Thereafter, PASTOR was implemented and evaluated in the same centres (intervention group). It consisted of six interprofessional modules, which were provided on 12 days in fixed groups, with a total extent of 48 hours. Participants were assessed with self-report measures at baseline, discharge, and 12 months for functional ability (primary outcome) using the Hannover Functional Ability Questionnaire (FFbH-R) and vari-ous secondary outcomes (e.g. pain, health status, physical activity, pain coping, pain-related cognitions). In total 536 participants were consecutively assigned to PASTOR (n=266) or MOR (n=270). At 12 months, complete data of 368 participants was available. The adjusted between-group difference in the FFbH-R at 12 months was 6.58 (95% CI 3.38 to 9.78) using complete data and 3.56 (95% CI 0.45 to 6.67) using available da-ta, corresponding to significant small-to-medium effect sizes of d=0.42 (p<0.001) and d=0.10 (p=0.025) in favour of PASTOR. Further improvements in secondary out-comes were also observed in favour of PASTOR. The interprofessional and interdisciplinary, biopsychosocial rehabilita-tion program PASTOR shows some improvements of the long-term effectiveness of inpatient rehabilitation in the management of adults with
2013-01-01
Background Registered Nurses (RNs) play an important role in caring for patients suffering from cancer pain. A lack of knowledge regarding pain management and the RNs’ own perception of cancer pain could act as barriers to effective pain management. Educational interventions that target RNs’ knowledge and attitudes have proved promising. However, an intervention consisting of evidence-based practice is a multifaceted process and demands behavioural and cognitive changes to sustain the effects of the intervention. Therefore, our study aimed to investigate if a theory-based educational intervention could change RNs’ knowledge and attitudes to cancer pain and pain management, both four and 12 weeks after the start of the intervention. Methods A quasi-experimental design with non-equivalent control groups was used. The primary outcome was measured using a modified version of the instrument Nurses’ Knowledge and Attitudes Survey Regarding Pain (NKAS) at baseline, four weeks and 12 weeks after the start of the intervention to evaluate its persistence. The intervention’s educational curriculum was based on the principles of Ajzen’s Theory of Planned Behaviour and consisted of interactive learning activities conducted in workshops founded on evidence-based knowledge. The RN’s own experiences from cancer pain management were used in the learning process. Results The theory-based educational intervention aimed at changing RNs knowledge and attitudes regarding cancer pain management measured by primary outcome NKAS resulted in a statistical significant (p<0.05) improvement of total mean score from baseline to four weeks at the intervention ward. Conclusions The findings of this study, suggest that a theory-based educational intervention focused at RNs can be effective in changing RN’s knowledge and attitudes regarding cancer pain management. However, the high number of dropouts between baseline and four weeks needs to be taken into account when evaluating our
Gustafsson, Markus; Borglin, Gunilla
2013-08-19
Registered Nurses (RNs) play an important role in caring for patients suffering from cancer pain. A lack of knowledge regarding pain management and the RNs' own perception of cancer pain could act as barriers to effective pain management. Educational interventions that target RNs' knowledge and attitudes have proved promising. However, an intervention consisting of evidence-based practice is a multifaceted process and demands behavioural and cognitive changes to sustain the effects of the intervention. Therefore, our study aimed to investigate if a theory-based educational intervention could change RNs' knowledge and attitudes to cancer pain and pain management, both four and 12 weeks after the start of the intervention. A quasi-experimental design with non-equivalent control groups was used. The primary outcome was measured using a modified version of the instrument Nurses' Knowledge and Attitudes Survey Regarding Pain (NKAS) at baseline, four weeks and 12 weeks after the start of the intervention to evaluate its persistence. The intervention's educational curriculum was based on the principles of Ajzen's Theory of Planned Behaviour and consisted of interactive learning activities conducted in workshops founded on evidence-based knowledge. The RN's own experiences from cancer pain management were used in the learning process. The theory-based educational intervention aimed at changing RNs knowledge and attitudes regarding cancer pain management measured by primary outcome NKAS resulted in a statistical significant (p<0.05) improvement of total mean score from baseline to four weeks at the intervention ward. The findings of this study, suggest that a theory-based educational intervention focused at RNs can be effective in changing RN's knowledge and attitudes regarding cancer pain management. However, the high number of dropouts between baseline and four weeks needs to be taken into account when evaluating our findings. Finally, this kind of theory
Equipment-based Pilates reduces work-related chronic low back pain and disability: A pilot study.
Stieglitz, Dana Duval; Vinson, David R; Hampton, Michelle De Coux
2016-01-01
This study investigated effectiveness of an equipment-based Pilates protocol for reducing pain and disability in individuals with work-related chronic low back pain (CLBP). Twelve workers with non-specific CLBP participated in a quasi-experimental, one-group, pretest-posttest pilot study of supervised 6-week equipment-based Pilates exercise. Pain severity was assessed using a 100-mm visual analog scale (VAS). Physical function was assessed using the Oswestry disability index (ODI). The Pilates intervention significantly reduced pain (mean decrease in VAS 30.75 ± 20.27, p < 0.0001) and disability (mean decrease in ODI 11.25 ± 13.20, p < 0.02) with large and borderline large effect sizes, respectively. Rehabilitative Pilates exercise reduced pain and disability in workers with CLBP. Further research is needed to investigate Pilates exercise for rehabilitation of work-related injuries in large populations. Copyright © 2015 Elsevier Ltd. All rights reserved.
2011-01-01
Background Albeit exercise is currently advocated as one of the most effective management strategies for fibromyalgia syndrome (FMS); the implementation of exercise as a FMS treatment in reality is significantly hampered by patients' poor compliance. The inference that pain catastrophizing is a key predictor of poor compliance in FMS patients, justifies considering the alteration of pain catastrophizing in improving compliance towards exercises in FMS patients. The aim of this study is to provide proof-of-concept for the development and testing of a novel virtual reality exposure therapy (VRET) program as treatment for exercise-related pain catastrophizing in FMS patients. Methods Two interlinked experimental studies will be conducted. Study 1 aims to objectively ascertain if neurophysiological changes occur in the functional brain areas associated with pain catastrophizing, when catastrophizing FMS subjects are exposed to visuals of exercise activities. Study 2 aims to ascertain the preliminary efficacy and feasibility of exposure to visuals of exercise activities as a treatment for exercise-related pain catastrophizing in FMS subjects. Twenty subjects will be selected from a group of FMS patients attending the Tygerberg Hospital in Cape Town, South Africa and randomly allocated to either the VRET (intervention) group or waiting list (control) group. Baseline neurophysiological activity for subjects will be collected in study 1 using functional magnetic resonance imaging (fMRI). In study 2, clinical improvement in pain catastrophizing will be measured using fMRI (objective) and the pain catastrophizing scale (subjective). Discussion The premise is if exposing FMS patients to visuals of various exercise activities trigger the functional brain areas associated with pain catastrophizing; then as a treatment, repeated exposure to visuals of the exercise activities using a VRET program could possibly decrease exercise-related pain catastrophizing in FMS patients. Proof
Barnhoorn, Karlijn J.; Staal, J. Bart; van Dongen, Robert T. M.; Frölke, Jan Paul M.; Klomp, Frank P.; van de Meent, Henk; Samwel, Han; Nijhuis-van der Sanden, Maria W. G.
2015-01-01
Objective To investigate whether pain-related fears are mediators for reducing disability and pain in patients with Complex Regional Pain Syndrome type 1 when treating with Pain Exposure Physical Therapy. Design An explorative secondary analysis of a randomised controlled trial. Participants Fifty-six patients with Complex Regional Pain Syndrome type 1. Interventions The experimental group received Pain Exposure Physical Therapy in a maximum of five treatment sessions; the control group received conventional treatment following the Dutch multidisciplinary guideline. Outcome measures Levels of disability, pain, and pain-related fears (fear-avoidance beliefs, pain catastrophizing, and kinesiophobia) were measured at baseline and after 3, 6, and 9 months follow-up. Results The experimental group had a significantly larger decrease in disability of 7.77 points (95% CI 1.09 to 14.45) and in pain of 1.83 points (95% CI 0.44 to 3.23) over nine months than the control group. The potential mediators pain-related fears decreased significantly in both groups, but there were no significant differences between groups, which indicated that there was no mediation. Conclusion The reduction of pain-related fears was comparable in both groups. We found no indication that pain-related fears mediate the larger reduction of disability and pain in patients with Complex Regional Pain Syndrome type 1 treated with Pain Exposure Physical Therapy compared to conventional treatment. Trial registration International Clinical Trials Registry NCT00817128 PMID:25919011
Depression and Pain in Asian and White Americans With Knee Osteoarthritis.
Ahn, Hyochol; Weaver, Michael; Lyon, Debra; Choi, Eunyoung; Fillingim, Roger B
2017-10-01
Few studies have examined the underlying psychosocial mechanisms of pain in Asian Americans. Using the biopsychosocial model, we sought to determine whether variations in depression contribute to racial group differences in symptomatic knee osteoarthritis pain between Asian Americans and non-Hispanic white Americans. The sample consisted of 100 participants, including 50 Asian Americans (28 Korean Americans, 9 Chinese Americans, 7 Japanese Americans, 5 Filipino Americans, and 1 Indian American) and 50 age- and sex-matched non-Hispanic white Americans with symptomatic knee osteoarthritis pain. The Centers for Epidemiologic Studies Depression Scale was used to assess symptoms of depression, and the Western Ontario and McMaster Universities Osteoarthritis Index and the Graded Chronic Pain Scale were used to measure clinical pain. In addition, quantitative sensory testing was used to measure experimental sensitivity to heat- and mechanically-induced pain. The results indicated that higher levels of depression in Asian Americans may contribute to greater clinical pain and experimental pain sensitivity. These findings add to the growing literature regarding ethnic and racial differences in pain and its associated psychological conditions, and additional research is warranted to strengthen these findings. This article shows the contribution of depression to clinical pain and experimental pain sensitivity in Asian Americans with knee osteoarthritis. Our results suggest that Asian Americans have higher levels of depressive symptoms and that depression plays a relevant role in greater clinical pain and experimental pain sensitivity in Asian Americans. Copyright © 2017 American Pain Society. Published by Elsevier Inc. All rights reserved.
Pain perception studies in tension-type headache.
Bezov, David; Ashina, Sait; Jensen, Rigmor; Bendtsen, Lars
2011-02-01
Tension-type headache (TTH) is a disorder with high prevalence and significant impact on society. Understanding of pathophysiology of TTH is paramount for development of effective treatments and prevention of chronification of TTH. Our aim was to review the findings from pain perception studies of pathophysiology of TTH as well as to review the research of pathophysiology of TTH. Pain perception studies such as measurement of muscle tenderness, pain detection thresholds, pain tolerance thresholds, pain response to suprathreshold stimulation, temporal summation and diffuse noxious inhibitory control (DNIC) have played a central role in elucidating the pathophysiology of TTH. It has been demonstrated that continuous nociceptive input from peripheral myofascial structures may induce central sensitization and thereby chronification of the headache. Measurements of pain tolerance thresholds and suprathreshold stimulation have shown presence of generalized hyperalgesia in chronic tension-type headache (CTTH) patients, while DNIC function has been shown to be reduced in CTTH. One imaging study showed loss of gray matter structures involved in pain processing in CTTH patients. Future studies should aim to integrate pain perception and imaging to confirm this finding. Pharmacological studies have shown that drugs like tricyclic anti-depressant amitriptyline and nitric oxide synthase inhibitors can reverse central sensitization and the chronicity of headache. Finally, low frequency electrical stimulation has been shown to rapidly reverse central sensitization and may be a new modality in treatment of CTTH and other chronic pain disorders. © 2010 American Headache Society.
Different pain responses to chronic and acute pain in various ethnic/racial groups.
Rahavard, Behnoosh B; Candido, Kenneth D; Knezevic, Nebojsa Nick
2017-09-01
Our goal in this study was to review the similarities and differences among ethnic groups and their respective responses to acute and chronic clinically related and experimentally induced pain. In this review, the PUBMED and Google-Scholar databases were searched to analyze articles that have assessed the variations in both acute and chronic pain responses among different ethnic/racial groups. According to the results from 42 reviewed articles, significant differences exist among ethnic-racial groups for pain prevalence as well as responses to acute and chronic pain. Compared with Caucasians, other ethnic groups are more susceptible to acute pain responses to nociceptive stimulation and to the development of long-term chronic pain. These differences need to be addressed and assessed more extensively in the future in order to minimize the pain management disparities among various ethnic-racial groups and also to improve the relationship between pain management providers and their patients.
Paul-Murphy, Joanne R.; Krugner-Higby, Lisa A.; Tourdot, Renee L.; Sladky, Kurt K.; Klauer, Julia M.; Keuler, Nicholas S.; Brown, Carolyn S.; Heath, Timothy D.
2014-01-01
Objective To evaluate injection of microcrystalline sodium urate (MSU) for inducing articular pain in green-cheeked conures (Pyrrhura molinae) and the analgesic efficacy of liposome-encapsulated butorphanol tartrate (LEBT) by use of weight load data, behavioral scores, and fecal corticosterone concentration. Animals 8 conures. Procedures In a crossover study, conures were randomly assigned to receive LEBT (15 mg/kg) or liposomal vehicle subsequent to experimental induction of arthritis or sham injection. The MSU was injected into 1 tibiotarsal-tarsometatarsal (intertarsal) joint to induce arthritis (time 0). Weight-bearing load and behavioral scores were determined at 0, 2, 6, 26, and 30 hours. Results MSU injection into 1 intertarsal joint caused a temporary decrease in weight bearing on the affected limb. Treatment of arthritic conures with LEBT resulted in significantly more weight bearing on the arthritic limb than treatment with vehicle. Administration of vehicle to arthritic conures caused a decrease in activity and feeding behaviors during the induction phase of arthritis, but as the arthritis resolved, there was a significant increase in voluntary activity at 30 hours and feeding behaviors at 26 and 30 hours, compared with results for LEBT treatment of arthritic birds. Treatment with LEBT or vehicle in conures without arthritis resulted in similar measurements for weight bearing and voluntary and motivated behaviors. Conclusions and Clinical Relevance Experimental induction of arthritis in conures was a good method for evaluating tonic pain. Weight-bearing load was the most sensitive measure of pain associated with induced arthritis. Pain associated with MSU-induced arthritis was alleviated by administration of LEBT. PMID:19795935
Enhancing cancer pain control regimens through patient education.
Rimer, B; Levy, M H; Keintz, M K; Fox, L; Engstrom, P F; MacElwee, N
1987-12-01
The problem of cancer-related pain afflicts millions of people annually. The study described here was aimed at improving cancer patients' pain control through a planned patient education program. A randomized clinical trial with a Solomon Four-Group design was used to assess the effectiveness of a patient education intervention consisting of nurse counseling and printed materials. The sample included 230 cancer patients. One month later, patients in the experimental group were more likely to have taken their pain medicine on the correct schedule and to have taken the correct dosage. The experimental group also was significantly less likely to report stopping the medicine when they felt better. In addition, they were significantly less worried about tolerance and addiction to pain medicines. Forty-four percent of the experimental group compared to 24% of the control group reported no or mild pain at the posttest.
Space Adaptation Back Pain: A Retrospective Study
NASA Technical Reports Server (NTRS)
Kerstman, E. L.; Scheuring, R. A.; Barnes, M. G.; DeKorse, T. B.; Saile, L. G.
2008-01-01
Back pain is frequently reported by astronauts during the early phase of space flight as they adapt to the microgravity environment. However, the epidemiology of space adaptation back pain has not been well defined. The purpose of this retrospective study was to develop a case definition of space adaptation back pain, determine the incidence of space adaptation back pain, and determine the effectiveness of available treatments. Medical records from the Mercury, Apollo, Apollo-Soyuz Test Project (ASTP), Skylab, Mir, International Space Station (ISS), and Shuttle programs were reviewed. All episodes of in-flight back pain that met the criteria for space adaptation back pain were recorded. Pain characteristics, including intensity, location, and duration of the pain were noted. The effectiveness of specific treatments also was recorded. The incidence of space adaptation back pain among astronauts was determined to be 53% (384/722). Most of the affected astronauts reported mild pain (85%). Moderate pain was reported by 11% of the affected astronauts and severe pain was reported by only 4% of the affected astronauts. The most effective treatments were fetal positioning (91% effective) and the use of analgesic medications (85% effective). This retrospective study aids in the development of a case definition of space adaptation back pain and examines the epidemiology of space adaptation back pain. Space adaptation back pain is usually mild and self-limited. However, there is a risk of functional impairment and mission impact in cases of moderate or severe pain that do not respond to currently available treatments. Therefore, the development of preventive measures and more effective treatments should be pursued.
Effect of experimental stress in 2 different pain conditions affecting the facial muscles.
Woda, Alain; L'heveder, Gildas; Ouchchane, Lemlih; Bodéré, Céline
2013-05-01
Chronic facial muscle pain is a common feature in both fibromyalgia (FM) and myofascial (MF) pain conditions. In this controlled study, a possible difference in the mode of deregulation of the physiological response to a stressing stimulus was explored by applying an acute mental stress to FM and MF patients and to controls. The effects of the stress test were observed on pain, sympathetic variables, and both tonic and reflex electromyographic activities of masseteric and temporal muscles. The statistical analyses were performed through a generalized linear model including mixed effects. Painful reaction to the stressor was stronger (P < .001) and longer (P = .011) in FM than in MF independently of a higher pain level at baseline. The stress-induced autonomic changes only seen in FM patients did not reach significance. The electromyographic responses to the stress test were strongest for controls and weakest for FM. The stress test had no effect on reflex activity (area under the curve [AUC]) or latency, although AUC was high in FM and latencies were low in both pain groups. It is suggested that FM is characterized by a lower ability to adapt to acute stress than MF. This study showed that an acute psychosocial stress triggered several changes in 2 pain conditions including an increase in pain of larger amplitude in FM than in MF pain. Similar stress-induced changes should be explored as possible mechanisms for differentiation between dysfunctional pain conditions. Copyright © 2013 American Pain Society. Published by Elsevier Inc. All rights reserved.
Neuropathic pain in the orofacial region: The role of pain history. A retrospective study.
Dieb, W; Moreau, N; Chemla, I; Descroix, V; Boucher, Y
2017-06-01
Orofacial neuropathic pain is often difficult to treat, mostly because of still unclear underlying mechanisms. The occurrence of such neuropathic pain varies depending on different factors, of which preexisting preoperative pain seems to be of high importance. The aim of this study was thus to test the hypothesis that prior history of pain could indeed be considered a risk factor for the development of orofacial neuropathic pain in the same region. The study was performed in the dental department of the Groupe Hospitalier Pitié-Salpêtrière (GHPS) in Paris, France. We investigated the presence of prior inflammatory pain before development of orofacial neuropathic pain in 56 patients. For each patient file, the following items were collected: age, gender; medical history; diagnosis; description of the pain (at time of consultation); presence or absence of prior dental treatment; date and type of dental treatment received. 41 patients (73%) of orofacial neuropathic pain patients had a history of pain compatible with an inflammatory condition; 4% (n=2) did not report any prior pain and 23% (n=13) could not remember. Among the patients with documented history of pain prior to neuropathy, 88% (n=36) received surgical treatment; 61%, (n=25) endodontic treatment and 22%, (n=9) restorative treatment. All eventually received endodontic treatment or tooth extraction. These dental treatments are compatible with the hypothesis of prior inflammatory pain in these patients. These results support the hypothesis that prior inflammatory pain could favor the development of orofacial neuropathic pain. Prevention and treatment of inflammatory trigeminal pain may therefore play a key role in preventing future neuropathic pain development. Copyright © 2017 Elsevier Masson SAS. All rights reserved.
Becker, Susanne; Ceko, Marta; Louis-Foster, Mytsumi; Elfassy, Nathaniel M.; Leyton, Marco; Shir, Yoram; Schweinhardt, Petra
2013-01-01
Based on animal studies and some indirect clinical evidence, dopamine has been suggested to have anti-nociceptive effects. Here, we investigated directly the effects of increased and decreased availability of extracellular dopamine on pain perception in healthy volunteers. In Study 1, participants ingested, in separate sessions, a placebo and a low dose of the centrally acting D2-receptor antagonist sulpiride, intended to increase synaptic dopamine via predominant pre-synaptic blockade. No effects were seen on thermal pain thresholds, tolerance, or temporal summation. Study 2 used the acute phenylalanine and tyrosine depletion (APTD) method to transiently decrease dopamine availability. In one session participants ingested a mixture that depletes the dopamine amino acid precursors, phenylalanine and tyrosine. In the other session they ingested a nutritionally balanced control mixture. APTD led to a small mood-lowering response following aversive thermal stimulation, but had no effects on the perception of cold, warm, or pain stimuli. In both studies the experimental manipulation of dopaminergic neurotransmission was successful as indicated by manipulation checks. The results contradict proposals that dopamine has direct anti-nociceptive effects in acute experimental pain. Based on dopamine’s well-known role in reward processing, we hypothesize that also in the context of pain, dopamine acts on stimulus salience and might play a role in the initiation of avoidance behavior rather than having direct antinociceptive effects in acute experimental pain. PMID:24236199
Horticultural therapy for patients with chronic musculoskeletal pain: results of a pilot study.
Verra, M L; Verra, Martin L; Angst, Felix; Beck, Trudi; Lehmann, Susanne; Brioschi, Roberto; Schneiter, Renata; Aeschlimann, Andre
2012-01-01
Therapists can use horticultural therapy as an adjuvant therapy in a non threatening context, with the intent of bringing about positive effects in physical health, mental health, and social interaction. Very few experimental studies exist that test its clinical effectiveness. To determine whether the addition of horticultural therapy to a pain-management program improved physical function, mental health, and ability to cope with pain. The research team designed a prospective, nonrandomized, controlled cohort study, enrolling all patients consecutively referred to the Zurzach Interdisciplinary Pain Program (ZISP) who met the studys criteria. The team divided them into two cohorts based on when medical professionals referred them: before (control group) or after (intervention group) introduction of a horticultural therapy program. The setting was the rehabilitation clinic (RehaClinic) in Bad Zurzach, Switzerland. Seventy-nine patients with chronic musculoskeletal pain (fibromyalgia or chronic, nonspecific back pain) participated in the study. The research team compared a 4-week, inpatient, interdisciplinary pain-management program with horticultural therapy (intervention, n = 37) with a pain-management program without horticultural therapy (control, n = 42). The horticultural therapy program consisted of seven sessions of group therapy, each of 1-hour duration. The research team assessed the outcome using the Medical Outcome Study Short Form-36 (SF-36), the West Haven-Yale Multidimensional Pain Inventory (MPI), the Hospital Anxiety and Depression Scale (HADS), the Coping Strategies Questionnaire (CSQ ), and two functional performance tests. The team tested participants on entry to and discharge from the 4-week pain-management program. Between-group differences in sociodemographic and outcome variables were not significant on participants entry to the pain-management program. On discharge, the research team measured small to moderate outcome effects (effect size [ES
... to Cancer Off-Label Drug Use Access to Experimental Drugs Complementary & Alternative Medicine (CAM) CAM for Patients ... called acupuncture points . Acupuncture may be used to control pain, including pain related to ... Support groups help many patients. Religious counseling may ...
Night-shift work is associated with increased pain perception.
Matre, Dagfinn; Knardahl, Stein; Nilsen, Kristian Bernhard
2017-05-01
Objectives The aim of the present study was to determine whether shift workers exhibit increased perception of experimentally induced pain after working night shifts. Methods The study was a paired cross-over design with two sleep conditions, after at least two nights of habitual sleep and after two consecutive night shifts at work. Fifty-three nurses in rotating shift work participated. The sensitivity to electrically induced pain, heat pain, cold pain, pressure pain and pain inhibition was determined experimentally in each sleep condition. Sleepiness and vigilance were also assessed. Results Night-shift work (NSW) increased the sensitivity to electrically induced pain and heat pain (P≤0.001). Relative to habitual sleep, electrically induced pain increased by 22.3% and heat pain increased by 26.5%. The sensitivity to cold and pressure pain did not change, changes relative to habitual sleep was <5% (P>0.5). Pain inhibition was 66.9% stronger after NSW versus after habitual sleep (P<0.001). Sleepiness (measured with the Karolinska Sleepiness Scale) increased from 4.1 after habitual sleep to 6.9 after NSW (P<0.001). Vigilance decreased after NSW, measured as a 0.03-second decrease in reaction time (P<0.005). Conclusions Changes in pain sensitivity after NSW is measurable with clinically relevant effect sizes and may be an important marker for studies comparing the physiological effects of different shift work schedules. Explanations for the differential effect on different pain modalities should be a focus for future studies.
Contextual influences on pain communication in couples with and without a partner with chronic pain.
Gagnon, Michelle M; Hadjistavropoulos, Thomas; MacNab, Ying C
2017-10-01
This is an experimental study of pain communication in couples. Despite evidence that chronic pain in one partner impacts both members of the dyad, dyadic influences on pain communication have not been sufficiently examined and are typically studied based on retrospective reports. Our goal was to directly study contextual influences (ie, presence of chronic pain, gender, relationship quality, and pain catastrophizing) on self-reported and nonverbal (ie, facial expressions) pain responses. Couples with (n = 66) and without (n = 65) an individual with chronic pain (ICP) completed relationship and pain catastrophizing questionnaires. Subsequently, one partner underwent a pain task (pain target, PT), while the other partner observed (pain observer, PO). In couples with an ICP, the ICP was assigned to be the PT. Pain intensity and PO perceived pain intensity ratings were recorded at multiple intervals. Facial expressions were video recorded throughout the pain task. Pain-related facial expression was quantified using the Facial Action Coding System. The most consistent predictor of either partner's pain-related facial expression was the pain-related facial expression of the other partner. Pain targets provided higher pain ratings than POs and female PTs reported and showed more pain, regardless of chronic pain status. Gender and the interaction between gender and relationship satisfaction were predictors of pain-related facial expression among PTs, but not POs. None of the examined variables predicted self-reported pain. Results suggest that contextual variables influence pain communication in couples, with distinct influences for PTs and POs. Moreover, self-report and nonverbal responses are not displayed in a parallel manner.
CCL2 and CCL3 are essential mediators of pelvic pain in experimental autoimmune prostatitis
Quick, Marsha L.; Mukherjee, Soumi; Rudick, Charles N.; Done, Joseph D.; Schaeffer, Anthony J.
2012-01-01
Experimental autoimmune prostatitis (EAP) is a murine model of chronic prostatitis/chronic pelvic pain syndrome (CPPS) in men, a syndrome characterized by chronic pelvic pain. We have demonstrated that chemokine ligands CCL2 and CCL3 are biomarkers that correlate with pelvic pain symptoms. We postulated that CCL2 and CCL3 play a functional role in CPPS and therefore examined their expression in EAP. Upon examination of the prostate 5 days after induction of EAP, CCL2 mRNA was elevated 2- to 3-fold, CCL8 by 15-fold, CCL12 by 12- to 13-fold, and CXCL9 by 2- to 4-fold compared with control mice. At 10 days the major chemokines were CXCL13 and CXCL2; at 20 days CCL2 (1- to 2-fold), CCL3 (2- to 3-fold) and CCL11 (2- to 3-fold); and at 30 days, CCL12 (20- to 35-fold) and smaller increases in CCL2, CCL3, and XCL1. Chemokine elevations were accompanied by increases in mast cells and B cells at 5 days, monocytes and neutrophils at day 10, CD4+ T cells at day 20, and CD4+ and CD8+ T cells at day 30. Anti-CCL2 and anti-CCL3 neutralizing antibodies administered at EAP onset attenuated pelvic pain development, but only anti-CCL2 antibodies were effective therapeutically. CCL2- and its cognate receptor CCR2-deficient mice were completely protected from development of pain symptoms but assumed susceptibility after reconstitution with wild-type bone marrow. CCL3-deficient mice showed resistance to the maintenance of pelvic pain while CCR5-deficient mice did not show any lessening of pelvic pain severity. These results suggest that the CCL2-CCR2 axis and CCL3 are important mediators of chronic pelvic pain in EAP. PMID:22814670
Orbitofrontal disinhibition of pain in migraine with aura: an interictal EEG-mapping study.
Lev, Rina; Granovsky, Yelena; Yarnitsky, David
2010-08-01
This study aimed to identify the cortical mechanisms underlying the processes of interictal dishabituation to experimental pain in subjects suffering from migraine with aura (MWA). In 21 subjects with MWA and 22 healthy controls, cortical responses to two successive trials of noxious contact-heat stimuli were analyzed using EEG-tomography software. When compared with controls, MWA patients showed significantly increased pain-evoked potential amplitudes accompanied by reduced activity in the orbitofrontal cortex (OFC) and increased activity in the pain matrix regions, including the primary somatosensory cortex (SI) (p < .05). Similarly to controls, MWA subjects displayed an inverse correlation between the OFC and SI activities, and positive interrelations between other pain-specific regions. The activity changes in the OFC negatively correlated with lifetime headache duration and longevity (p < .05). Reduced inhibitory functioning of the prefrontal cortex is a possible cause for disinhibition of the pain-related sensory cortices in migraine. The finding of OFC hypofunction over the disease course is in keeping with current concepts of migraine as a progressive brain disorder.
Benson, Curtis; Paylor, John W; Tenorio, Gustavo; Winship, Ian; Baker, Glen; Kerr, Bradley J
2015-09-01
Multiple sclerosis (MS) is classically defined by motor deficits, but it is also associated with the secondary symptoms of pain, depression, and anxiety. Up to this point modifying these secondary symptoms has been difficult. There is evidence that both MS and the animal model experimental autoimmune encephalomyelitis (EAE), commonly used to study the pathophysiology of the disease, can be modulated by exercise. To examine whether limited voluntary wheel running could modulate EAE disease progression and the co-morbid symptoms of pain, mice with EAE were allowed access to running wheels for 1h every day. Allowing only 1h every day of voluntary running led to a significant delay in the onset of clinical signs of the disease. The development of mechanical allodynia was assessed using Von Frey hairs and indicated that wheel running had a modest positive effect on the pain hypersensitivity associated with EAE. These behavioral changes were associated with reduced numbers of cFOS and phosphorylated NR1 positive cells in the dorsal horn of the spinal cord compared to no-run EAE controls. In addition, within the dorsal horn, voluntary wheel running reduced the number of infiltrating CD3(+) T-cells and reduced the overall levels of Iba1 immunoreactivity. Using high performance liquid chromatography (HPLC), we observed that wheel-running lead to significant changes in the spinal cord levels of the antioxidant glutathione. Oxidative stress has separately been shown to contribute to EAE disease progression and neuropathic pain. Together these results indicate that in mice with EAE, voluntary motor activity can delay the onset of clinical signs and reduce pain symptoms associated with the disease. Copyright © 2015 Elsevier Inc. All rights reserved.
Pain point system scale (PPSS): a method for postoperative pain estimation in retrospective studies
Gkotsi, Anastasia; Petsas, Dimosthenis; Sakalis, Vasilios; Fotas, Asterios; Triantafyllidis, Argyrios; Vouros, Ioannis; Saridakis, Evangelos; Salpiggidis, Georgios; Papathanasiou, Athanasios
2012-01-01
Purpose Pain rating scales are widely used for pain assessment. Nevertheless, a new tool is required for pain assessment needs in retrospective studies. Methods The postoperative pain episodes, during the first postoperative day, of three patient groups were analyzed. Each pain episode was assessed by a visual analog scale, numerical rating scale, verbal rating scale, and a new tool – pain point system scale (PPSS) – based on the analgesics administered. The type of analgesic was defined based on the authors’ clinic protocol, patient comorbidities, pain assessment tool scores, and preadministered medications by an artificial neural network system. At each pain episode, each patient was asked to fill the three pain scales. Bartlett’s test and Kaiser–Meyer–Olkin criterion were used to evaluate sample sufficiency. The proper scoring system was defined by varimax rotation. Spearman’s and Pearson’s coefficients assessed PPSS correlation to the known pain scales. Results A total of 262 pain episodes were evaluated in 124 patients. The PPSS scored one point for each dose of paracetamol, three points for each nonsteroidal antiinflammatory drug or codeine, and seven points for each dose of opioids. The correlation between the visual analog scale and PPSS was found to be strong and linear (rho: 0.715; P < 0.001 and Pearson: 0.631; P < 0.001). Conclusion PPSS correlated well with the known pain scale and could be used safely in the evaluation of postoperative pain in retrospective studies. PMID:23152699
Louca Jounger, Sofia; Christidis, Nikolaos; Hedenberg-Magnusson, Britt; List, Thomas; Svensson, Peter; Schalling, Martin; Ernberg, Malin
2016-01-01
The aim of this study was to investigate experimentally if 5-HT3 single nucleotide polymorphisms (SNP) contribute to pain perception and efficacy of the 5-HT3-antagonist granisetron and sex differences. Sixty healthy participants were genotyped regarding HTR3A (rs1062613) and HTR3B (rs1176744). First, pain was induced by bilateral hypertonic saline injections (HS, 5.5%, 0.2 mL) into the masseter muscles. Thirty min later the masseter muscle on one side was pretreated with 0.5 mL granisetron (1 mg/mL) and on the other side with 0.5 mL placebo (isotonic saline) followed by another HS injection (0.2 mL). Pain intensity, pain duration, pain area and pressure pain thresholds (PPTs) were assessed after each injection. HS evoked moderate pain, with higher intensity in the women (P = 0.023), but had no effect on PPTs. None of the SNPs influenced any pain variable in general, but compared to men, the pain area was larger in women carrying the C/C (HTR3A) (P = 0.015) and pain intensity higher in women with the A/C alleles (HTR3B) (P = 0.019). Pre-treatment with granisetron reduced pain intensity, duration and area to a lesser degree in women (P < 0.05), but the SNPs did not in general influence the efficacy of granisetron. Women carrying the C/T & T/T (HTR3A) genotype had less reduction of pain intensity (P = 0.041) and area (P = 0.005), and women with the C/C genotype (HTR3B) had less reduction of pain intensity (P = 0.030), duration (P = 0.030) and area compared to men (P = 0.017). In conclusion, SNPs did not influence experimental muscle pain or the effect of granisetron on pain variables in general, but there were some sex differences in pain variables that seem to be influenced by genotypes. However, due to the small sample size further research is needed before any firm conclusions can be drawn.
Hedenberg-Magnusson, Britt; List, Thomas; Svensson, Peter; Schalling, Martin
2016-01-01
The aim of this study was to investigate experimentally if 5-HT3 single nucleotide polymorphisms (SNP) contribute to pain perception and efficacy of the 5-HT3-antagonist granisetron and sex differences. Sixty healthy participants were genotyped regarding HTR3A (rs1062613) and HTR3B (rs1176744). First, pain was induced by bilateral hypertonic saline injections (HS, 5.5%, 0.2 mL) into the masseter muscles. Thirty min later the masseter muscle on one side was pretreated with 0.5 mL granisetron (1 mg/mL) and on the other side with 0.5 mL placebo (isotonic saline) followed by another HS injection (0.2 mL). Pain intensity, pain duration, pain area and pressure pain thresholds (PPTs) were assessed after each injection. HS evoked moderate pain, with higher intensity in the women (P = 0.023), but had no effect on PPTs. None of the SNPs influenced any pain variable in general, but compared to men, the pain area was larger in women carrying the C/C (HTR3A) (P = 0.015) and pain intensity higher in women with the A/C alleles (HTR3B) (P = 0.019). Pre-treatment with granisetron reduced pain intensity, duration and area to a lesser degree in women (P < 0.05), but the SNPs did not in general influence the efficacy of granisetron. Women carrying the C/T & T/T (HTR3A) genotype had less reduction of pain intensity (P = 0.041) and area (P = 0.005), and women with the C/C genotype (HTR3B) had less reduction of pain intensity (P = 0.030), duration (P = 0.030) and area compared to men (P = 0.017). In conclusion, SNPs did not influence experimental muscle pain or the effect of granisetron on pain variables in general, but there were some sex differences in pain variables that seem to be influenced by genotypes. However, due to the small sample size further research is needed before any firm conclusions can be drawn. PMID:28002447
Development and Initial Validation of the Pain Resilience Scale.
Slepian, P Maxwell; Ankawi, Brett; Himawan, Lina K; France, Christopher R
2016-04-01
Over the past decade, the role of positive psychology in pain experience has gained increasing attention. One such positive factor, identified as resilience, has been defined as the ability to maintain positive emotional and physical functioning despite physical or psychological adversity. Although cross-situational measures of resilience have been shown to be related to pain, it was hypothesized that a pain-specific resilience measure would serve as a stronger predictor of acute pain experience. To test this hypothesis, we conducted a series of studies to develop and validate the Pain Resilience Scale. Study 1 described exploratory and confirmatory factor analyses that support a scale with 2 distinct factors, Cognitive/Affective Positivity and Behavioral Perseverance. Study 2 showed test-retest reliability and construct validity of this new scale, including moderate positive relationships with measures of positive psychological functioning and small to moderate negative relationships with vulnerability measures such as pain catastrophizing. Finally, consistent with our initial hypothesis, study 3 showed that the Pain Resilience Scale is more strongly related to ischemic pain responses than existing measures of general resilience. Together, these studies support the predictive utility of this new pain-specific measure of resilience in the context of acute experimental pain. The Pain Resilience Scale represents a novel measure of Cognitive/Affective Positivity and Behavioral Perseverance during exposure to noxious stimuli. Construct validity is supported by expected relationships with existing pain-coping measures, and predictive validity is shown by individual differences in response to acute experimental pain. Copyright © 2016 American Pain Society. Published by Elsevier Inc. All rights reserved.
Motor-Evoked Pain Increases Force Variability in Chronic Jaw Pain.
Wang, Wei-En; Roy, Arnab; Misra, Gaurav; Archer, Derek B; Ribeiro-Dasilva, Margarete C; Fillingim, Roger B; Coombes, Stephen A
2018-06-01
Musculoskeletal pain changes how people move. Although experimental pain is associated with increases in the variability of motor output, it is not clear whether motor-evoked pain in clinical conditions is also associated with increases in variability. In the current study, we measured jaw force production during a visually guided force paradigm in which individuals with chronic jaw pain and control subjects produced force at 2% of their maximum voluntary contraction (low target force level) and at 15% of their maximum voluntary contraction (high target force level). State measures of pain were collected before and after each trial. Trait measures of pain intensity and pain interference, self-report measures of jaw function, and measures of depression, anxiety, and fatigue were also collected. We showed that the chronic jaw pain group exhibited greater force variability compared with controls irrespective of the force level, whereas the accuracy of force production did not differ between groups. Furthermore, predictors of force variability shifted from trait measures of pain intensity and pain interference at the low force level to state measures of pain intensity at the high force level. Our observations show that motor-evoked jaw pain is associated with increases in force variability that are predicted by a combination of trait measures and state measures of pain intensity and pain interference. Chronic jaw pain is characterized by increases in variability during force production, which can be predicted by pain intensity and pain interference. This report could help clinicians better understand the long-term consequences of chronic jaw pain on the motor system. Copyright © 2018 The American Pain Society. Published by Elsevier Inc. All rights reserved.
Operant conditioning of enhanced pain sensitivity by heat-pain titration.
Becker, Susanne; Kleinböhl, Dieter; Klossika, Iris; Hölzl, Rupert
2008-11-15
Operant conditioning mechanisms have been demonstrated to be important in the development of chronic pain. Most experimental studies have investigated the operant modulation of verbal pain reports with extrinsic reinforcement, such as verbal reinforcement. Whether this reflects actual changes in the subjective experience of the nociceptive stimulus remained unclear. This study replicates and extends our previous demonstration that enhanced pain sensitivity to prolonged heat-pain stimulation could be learned in healthy participants through intrinsic reinforcement (contingent changes in nociceptive input) independent of verbal pain reports. In addition, we examine whether different magnitudes of reinforcement differentially enhance pain sensitivity using an operant heat-pain titration paradigm. It is based on the previously developed non-verbal behavioral discrimination task for the assessment of sensitization, which uses discriminative down- or up-regulation of stimulus temperatures in response to changes in subjective intensity. In operant heat-pain titration, this discriminative behavior and not verbal pain report was contingently reinforced or punished by acute decreases or increases in heat-pain intensity. The magnitude of reinforcement was varied between three groups: low (N1=13), medium (N2=11) and high reinforcement (N3=12). Continuous reinforcement was applied to acquire and train the operant behavior, followed by partial reinforcement to analyze the underlying learning mechanisms. Results demonstrated that sensitization to prolonged heat-pain stimulation was enhanced by operant learning within 1h. The extent of sensitization was directly dependent on the received magnitude of reinforcement. Thus, operant learning mechanisms based on intrinsic reinforcement may provide an explanation for the gradual development of sustained hypersensitivity during pain that is becoming chronic.
You, Dokyoung S; Meagher, Mary W
2017-01-01
Individuals with greater borderline personality features may be vulnerable to chronic pain. Because pain is an unpleasant sensory and emotional experience, affect dysregulation as the core personality feature may be linked to pain hypersensitivity. Studies have found that greater borderline features are associated with increased intensity in clinical and experimental pain, and that depression mediates this increase. The current study further examined the association between borderline features and heat pain sensitivity, the contribution of affect dysregulation and the other borderline personality factors (identity problems, negative relationships, self-harming/impulsivity) to the association, and depression as a mediator. Additionally, we examined whether blunted sympathetic responses mediate the association between borderline features and temporal summation of second pain (TSSP). Thermal pain threshold, thermal TSSP and aftersensations pain were assessed in 79 healthy individuals with varying degrees of borderline features. TSSP is a proxy measure for central sensitization and refers to the gradual increase in pain to repeated nociceptive stimuli. A regression analysis showed that greater borderline features predicted greater TSSP (β = .22, p = .050, R 2 = .05). Borderline features were unrelated to pain threshold and TSSP decay. A stepwise regression showed greater TSSP in individuals with greater borderline features was accounted for by the negative relationships factor rather than the affect dysregulation factor. The results of mediational analyses showed depression and blunted sympathetic skin conductance responses mediated the positive association between TSSP and borderline features.
Taha, Omneya; Opitz, Thoralf; Mueller, Marcus; Pitsch, Julika; Becker, Albert; Evert, Bernd Oliver; Beck, Heinz; Jeub, Monika
2017-11-01
Guillain-Barré syndrome (GBS) is an acute, immune-mediated polyradiculoneuropathy characterized by rapidly progressive paresis and sensory disturbances. Moderate to severe and often intractable neuropathic pain is a common symptom of GBS, but its underlying mechanisms are unknown. Pathology of GBS is classically attributed to demyelination of large, myelinated peripheral fibers. However, there is increasing evidence that neuropathic pain in GBS is associated with impaired function of small, unmyelinated, nociceptive fibers. We therefore examined the functional properties of small DRG neurons, the somata of nociceptive fibers, in a rat model of GBS (experimental autoimmune neuritis=EAN). EAN rats developed behavioral signs of neuropathic pain. This was accompanied by a significant shortening of action potentials due to a more rapid repolarization and an increase in repetitive firing in a subgroup of capsaicin-responsive DRG neurons. Na + current measurements revealed a significant increase of the fast TTX-sensitive current and a reduction of the persistent TTX-sensitive current component. These changes of Na + currents may account for the significant decrease in AP duration leading to an overall increase in excitability and are therefore possibly directly linked to pathological pain behavior. Thus, like in other animal models of neuropathic and inflammatory pain, Na + channels seem to be crucially involved in the pathology of GBS and may constitute promising targets for pain modulating pharmaceuticals. Copyright © 2017 Elsevier Inc. All rights reserved.
Generating physical symptoms from visual cues: An experimental study.
Ogden, Jane; Zoukas, Serafim
2009-12-01
This experimental study explored whether the physical symptoms of cold, pain and itchiness could be generated by visual cues, whether they varied in the ease with which they could be generated and whether they were related to negative affect. Participants were randomly allocated by group to watch one of three videos relating to cold (e.g. ice, snow, wind), pain (e.g. sporting injuries, tattoos) or itchiness (e.g. head lice, scratching). They then rated their self-reported symptoms of cold, pain and itchiness as well as their negative affect (depression and anxiety). The researcher recorded their observed behaviour relating to these symptoms. The results showed that the interventions were successful and that all three symptoms could be generated by the visual cues in terms of both self-report and observed behaviour. In addition, the pain video generated higher levels of anxiety and depression than the other two videos. Further, the degree of itchiness was related to the degree of anxiety. This symptom onset process also showed variability between symptoms with self-reported cold symptoms being greater than either pain or itchy symptoms. The results show that physical symptoms can be generated by visual cues indicating that psychological factors are not only involved in symptom perception but also in symptom onset.
[Human milk for neonatal pain relief during ophthalmoscopy].
Ribeiro, Laiane Medeiros; Castral, Thaíla Corrêa; Montanholi, Liciane Langona; Daré, Mariana Firmino; Silva, Aline Carolina de Araújo; Antonini, Sonir Roberto Rauber; Scochi, Carmen Gracinda Silvan
2013-10-01
Ophthalmoscopy performed for the early diagnosis of retinopathy of prematurity (ROP) is painful for preterm infants, thus necessitating interventions for minimizing pain. The present study aimed to establish the effectiveness of human milk, compared with sucrose, for pain relief in premature infants subjected to ophthalmoscopy for the early diagnosis of ROP. This investigation was a pilot, quasi-experimental study conducted with 14 premature infants admitted to the neonatal intensive care unit (NICU) of a university hospital. Comparison between the groups did not yield a statistically significant difference relative to the crying time, salivary cortisol, or heart rate (HR). Human milk appears to be as effective as sucrose in relieving acute pain associated with ophthalmoscopy. The study's limitations included its small sample size and lack of randomization. Experimental investigations with greater sample power should be performed to reinforce the evidence found in the present study.
Is pain suffering? A case study.
Black, Helen K
2007-01-01
In this article, the case study of an elderly woman shows how bodily pain and suffering meld in her narrative, not as the subjective and objective sides of the same event, but as distinct experiences in which both constructs emerge separately or come together based on the meaning she imputes to the event. The case study shows the clear methodological fit of qualitative narrative research with the lived experiences of pain and suffering. The narrator recalled the "tremendous" pain she experienced almost 60 years previously as both suffering and not-suffering, depending on the outcome of the circumstances that surrounded her pain. This case shows how a significant aspect of the aging experience-suffering-is medicalized, yet remains resistant to both categorization and medicine.
Koh, Su-Jin; Keam, Bhumsuk; Hyun, Min Kyung; Ju Seo, Jeong; Uk Park, Keon; Oh, Sung Yong; Ahn, Jinseok; Lee, Ja Youn; Kim, JinShil
2018-03-26
More than half of the patients have reported improper management of breakthrough cancer pain. Empirical evidence is lacking concerning the effectiveness of cancer pain education on breakthrough pain control. This study aimed to examine the effects of individual pain education on pain control, use of short-acting analgesics for breakthrough pain, quality of life outcomes, and rectification of patients' misconceptions regarding cancer pain. A quasi-experimental design was used. In total, 176 (102 inpatients and 74 outpatients) and 163 (93 inpatients and 70 outpatients) cancer patients completed questionnaires on pain intensity, quality of life, use of short-acting medication for breakthrough pain, and misconceptions about cancer pain and opioid use before and immediately and/or seven days after individual pain education. The mean age of the participants was 60.9 years (±11.2), and 56.3% were male. The most common cancers were lung cancer (17.0%), colon cancer (15.9%), and breast cancer (12.5%). The subjects' reasons for attrition were conditional deterioration, death, or voluntary withdrawal (N = 13, 7.4%). Following the education, there was a significant reduction in overall pain intensity over 24 hours (P < 0.001). The outpatients showed more use of short-acting analgesics for breakthrough pain. Sleep quality change was most significantly associated with intervention; other quality of life aspects (e.g., general feelings and life enjoyment) also improved. Pain education also significantly reduced misconceptions regarding cancer pain management. The present educational intervention was effective in encouraging short-acting analgesic use for breakthrough pain, improving quality of life outcomes, and rectifying patients' misconceptions about analgesic use.
Shared Genetics of Temporomandibular Disorder Pain and Neck Pain: Results of a Twin Study.
Visscher, Corine M; Schouten, Maarten J; Ligthart, Lannie; van Houtem, Caroline Mhh; de Jongh, Ad; Boomsma, Dorret I
2018-03-06
(1) To examine the heritability of TMD pain and of neck pain; and (2) to estimate the potential overlap in genetic and environmental factors influencing TMD pain and neck pain. Data from 2,238 adult female twins who completed a survey on TMD pain and neck pain were analyzed. The total variance of TMD pain and neck pain was decomposed into variance attributable to additive genetic effects and nonshared environmental effects. Bivariate structural equation modeling was applied to estimate trait-specific and genetic effects shared between traits. The prevalence of TMD pain and neck pain was 8.6% and 46.8%, respectively, while 6.7% of the twins reported both TMD pain and neck pain. The phenotypic correlation between TMD pain and neck pain, based on a liability threshold model, was 0.43 (95% confidence interval [CI] 0.34 to 0.51). The heritability for TMD was 0.35 (0.17 to 0.51), and for neck pain was 0.33 (0.23 to 0.43). The genetic correlation between TMD pain and neck pain was 0.64 (0.35 to 1.00), and the environmental correlation was 0.32 (0.14 to 0.48). This study shows that variation in TMD pain and neck pain can in part be attributed to genes. The comorbidity between them is partly explained by genes that influence both traits and partly by the same environmental factors.
Gokyildiz Surucu, Sule; Ozturk, Melike; Avcibay Vurgec, Burcu; Alan, Sultan; Akbas, Meltem
2018-02-01
This study aims at analyzing the effect of music on pain and anxiety felt by women in labor during their first pregnancy. When the pregnant women in the experimental group progressed into the active phase of the labor, they were made to listen to music in Acemasiran mode with earplugs for 3 h (20 min of listening with 10-min breaks). It was observed that after the first-hour women indicated that their pain was statistically less in the experimental group. Trait anxiety scores of the women in labor were similar for experimental and control groups. Following the practice, state anxiety average scores became lower in favor of the experimental group and the correlation was statistically significant. In order to facilitate women's coping with labor pain and improve their wellbeing with the activity during the labor, musicotherapy, a non-pharmacological method, is an effective, simple and economical method. Copyright © 2017 Elsevier Ltd. All rights reserved.
[Schizophrenia and pain reactivity].
Bonnot, Olivier; Tordjman, Sylvie
2008-11-01
Medical practitioners do not for a long time pay enough attention to patient's pain. This approach is in the line of society feelings. Pain was long consider to be a contingency to withstand as showed in Christian's bible or Stoicism's principle. Changes in mentality appear in present times. It Seems obvious that for sociological and scientific reasons pain's care in medical and psychiatric disorders is now an important subject. Recent research in autistic disorders suggest that insensitivity observed in autism is not and analgesic phenomenon but a different behavioural reactivity to pain. Prevalence of schizophrenic disorder is from 0.5 to 1%. It is also a complex disorder that has defied decades of concerted efforts to uncover its origins and attenuate its symptoms. The most promising hypotheses suggest that neurodevelopmental impairment increases the risk of later schizophrenia. Most of recent researches in this topic did focus to trait or state markers. According to the vulnerability models of schizophrenia, trait marker are clinical, psychological, physiological, anatomical or cognitive impairments found in patients with schizophrenia during all the course of the illness and even before the onset. Several lines of evidence (case report, epidemiological studies, experimental studies) suggest that patients with schizophrenia shows a relative insensitivity to physical pain. We will review and critic the scientific literature in this specific topic. We will see if datas are relevant with the neurodevelopmental hypothesis and vulnerability models. An OLDMEDLINE/MEDLINE query was performed to identify 50 articles relevant to our subject. 9 were case report or case series, 21 were clinical or epidemiological studies, 15 were experimental studies and we also found 5 previous review. Clinical and experimental data strongly suggest a decrease of Behavioural Reactivity to Pain (BRP) but there is a lack of argument to prove a real analgesia. Because schizophrenia is a
Relieving patients' pain with expectation interventions: a meta-analysis.
Peerdeman, Kaya J; van Laarhoven, Antoinette I M; Keij, Sascha M; Vase, Lene; Rovers, Maroeska M; Peters, Madelon L; Evers, Andrea W M
2016-06-01
Patients' expectations are important predictors of the outcome of analgesic treatments, as demonstrated predominantly in research on placebo effects. Three commonly investigated interventions that have been found to induce expectations (verbal suggestion, conditioning, and mental imagery) entail promising, brief, and easy-to-implement adjunctive procedures for optimizing the effectiveness of analgesic treatments. However, evidence for their efficacy stems mostly from research on experimentally evoked pain in healthy samples, and these findings might not be directly transferable to clinical populations. The current meta-analysis investigated the effects of these expectation inductions on patients' pain relief. Five bibliographic databases were systematically searched for studies that assessed the effects of brief verbal suggestion, conditioning, or imagery interventions on pain in clinical populations, with patients experiencing experimental, acute procedural, or chronic pain, compared with no treatment or control treatment. Of the 15,955 studies retrieved, 30 met the inclusion criteria, of which 27 provided sufficient data for quantitative analyses. Overall, a medium-sized effect of the interventions on patients' pain relief was observed (Hedges g = 0.61, I = 73%), with varying effects of verbal suggestion (k = 18, g = 0.75), conditioning (always paired with verbal suggestion, k = 3, g = 0.65), and imagery (k = 6, g = 0.27). Subset analyses indicated medium to large effects on experimental and acute procedural pain and small effects on chronic pain. In conclusion, patients' pain can be relieved with expectation interventions; particularly, verbal suggestion for acute procedural pain was found to be effective.
Umapathy, Hema; Bennell, Kim; Dickson, Chris; Dobson, Fiona; Fransen, Marlene; Jones, Graeme; Hunter, David J
2015-07-07
Despite the availability of evidence-based guidelines for conservative treatment of osteoarthritis (OA), management is often confined to the use of analgesics and waiting for eventual total joint replacement. This suggests a gap in knowledge for persons with OA regarding the many different treatments available to them. Our objective was to evaluate outcomes after usage of a Web-based resource called My Joint Pain that contains tailored, evidence-based information and tools aimed to improve self-management of OA on self-management and change in knowledge. A quasi-experimental design was used to evaluate the My Joint Pain website intervention over a 12-month period. The intervention provided participants with general and user-specific information, monthly assessments with validated instruments, and progress-tracking tools. A nationwide convenience sample of 195 participants with self-assessed hip and/or knee OA completed both baseline and 12-month questionnaires (users: n=104; nonusers: n=91). The primary outcome measure was the Health Evaluation Impact Questionnaire (heiQ) to evaluate 8 different domains (health-directed activity, positive and active engagement in life, emotional distress, self-monitoring and insight, constructive attitudes and approaches, skill and technique acquisition, social integration and support, health service navigation) and the secondary outcome measure was the 17-item Osteoarthritis Quality Indicator (OAQI) questionnaire to evaluate the change in appropriateness of care received by participants. Independent t tests were used to compare changes between groups for the heiQ and chi-square tests to identify changes within and between groups from baseline to 12 months for each OAQI item. Baseline demographics between groups were similar for gender (152/195, 77.9% female), age (mean 60, SD 9 years) and body mass index (mean 31.1, SD 6.8 kg/m(2)). With the exception of health service navigation, mean effect sizes from all other heiQ domains
Neuropathic pain and use of PainDETECT in patients with fibromyalgia: a cohort study.
Gauffin, Jarno; Hankama, Tiina; Kautiainen, Hannu; Hannonen, Pekka; Haanpää, Maija
2013-02-14
Fibromyalgia has a plethorae of symptoms, which can be confusing and even misleading. Accurate evaluation is necessary when patients with fibromyalgia are treated. Different types of instruments are available for the clinicians to supplement evaluation. Our objective was to study the applicability of the PainDETECT instrument to screen neuropathic pain in patients with fibromyalgia. 158 patients with primary fibromyalgia underwent a neurological examination including bedside sensory testing. They also fulfilled four questionnaires: PainDETECT, Beck depression inventory IA (BDI IA), Fibromyalgia Impact Questionnaire (FIQ) and a self-made questionnaire regarding present pain and pain relieving methods of the patients. The results of the clinical evaluation and questionnaires were then compared. Clinically verified neuropathic pain was diagnosed in 53/158 [34% (95% Cl: 26 to 41)] patients. The ROC curve achieved a maximum Youden´s index at score of 17 when sensitivity was 0.79 (95% Cl: 0.66 to 0.89) and specificity 0.53 (95% Cl: 0.43 to 0.63). The PainDETECT total score (OR: 1.14 95% Cl: 1.06 to 1.22), FM as the worst current pain (OR: 0.31; 95% 0.16 to 0.62), body mass index (BMI) (OR: 1.05; 95% Cl: 1.00 to 1.11) and the intensity of current pain (OR: 1.20; 95% Cl: 1.01 to 1.41) were significantly associated with the presence of neuropathic pain in univariate analyses. This study highlights the importance of thorough clinical examination. The Neuropathic pain screening tool PainDETECT is not as useful in patients with fibromyalgia as in patients with uncompromised central pain control.
Thibodeau, Michel A; Welch, Patrick G; Katz, Joel; Asmundson, Gordon J G
2013-03-01
The sexes differ with respect to perception of experimental pain. Anxiety influences pain perception more in men than in women; however, there lacks research exploring which anxiety constructs influence pain perception differentially between men and women. Furthermore, research examining whether depression is associated with pain perception differently between the sexes remains scant. The present investigation was designed to examine how trait anxiety, pain-related anxiety constructs (ie, fear of pain, pain-related anxiety, anxiety sensitivity), and depression are associated with pain perception between the sexes. A total of 95 nonclinical participants (55% women) completed measures assessing the constructs of interest and participated in quantitative sensory testing using heat and cold stimuli administered by a Medoc Pathway Pain and Sensory Evaluation System. The findings suggest that pain-related anxiety constructs, but not trait anxiety, are associated with pain perception. Furthermore, these constructs are associated with pain intensity ratings in men and pain tolerance levels in women. This contrasts with previous research suggesting that anxiety influences pain perception mostly or uniquely in men. Depression was not systematically associated with pain perception in either sex. Systematic relationships were not identified that allow conclusions regarding how fear of pain, pain-related anxiety, and anxiety sensitivity may contribute to pain perception differentially in men and women; however, anxiety sensitivity was associated with increased pain tolerance, a novel finding needing further examination. The results provide directions for future research and clinical endeavors and support that fear and anxiety are important features associated with hyperalgesia in both men and women. Copyright © 2012 International Association for the Study of Pain. Published by Elsevier B.V. All rights reserved.
Kutch, Jason J; Ichesco, Eric; Hampson, Johnson P; Labus, Jennifer S; Farmer, Melissa A; Martucci, Katherine T; Ness, Timothy J; Deutsch, Georg; Apkarian, A Vania; Mackey, Sean C; Klumpp, David J; Schaeffer, Anthony J; Rodriguez, Larissa V; Kreder, Karl J; Buchwald, Dedra; Andriole, Gerald L; Lai, H Henry; Mullins, Chris; Kusek, John W; Landis, J Richard; Mayer, Emeran A; Clemens, J Quentin; Clauw, Daniel J; Harris, Richard E
2017-10-01
Chronic pain is often measured with a severity score that overlooks its spatial distribution across the body. This widespread pain is believed to be a marker of centralization, a central nervous system process that decouples pain perception from nociceptive input. Here, we investigated whether centralization is manifested at the level of the brain using data from 1079 participants in the Multidisciplinary Approach to the Study of Chronic Pelvic Pain Research Network (MAPP) study. Participants with a clinical diagnosis of urological chronic pelvic pain syndrome (UCPPS) were compared to pain-free controls and patients with fibromyalgia, the prototypical centralized pain disorder. Participants completed questionnaires capturing pain severity, function, and a body map of pain. A subset (UCPPS N = 110; fibromyalgia N = 23; healthy control N = 49) underwent functional and structural magnetic resonance imaging. Patients with UCPPS reported pain ranging from localized (pelvic) to widespread (throughout the body). Patients with widespread UCPPS displayed increased brain gray matter volume and functional connectivity involving sensorimotor and insular cortices (P < 0.05 corrected). These changes translated across disease diagnoses as identical outcomes were present in patients with fibromyalgia but not pain-free controls. Widespread pain was also associated with reduced physical and mental function independent of pain severity. Brain pathology in patients with centralized pain is related to pain distribution throughout the body. These patients may benefit from interventions targeting the central nervous system.
Hsieh, Annie Y; Tripp, Dean A; Ji, Li-Jun; Sullivan, Michael J L
2010-11-01
Experimental pain research indicates ethnic differences in pain experience. Most of the cross-cultural pain research studied African Americans and Hispanics with little data available for Asian groups. This study examined differences in pain catastrophizing, pain attitudes, and pain responses between Chinese and European Canadian young adults. Prior to completing a cold-pressor (CP) task, 80 Chinese and 80 European Canadian undergraduate students were administered measures of pain catastrophizing and pain attitudes, including stoicism and cautiousness. Pain threshold, pain tolerance, and pain intensity were measured during the CP task. The Short Form-McGill Pain Questionnaire was administered immediately postimmersion to measure sensory and affective pain. While there was no group difference in pain threshold and pain intensity, Chinese participants displayed lower pain tolerance and reported higher SF-MPQ-Affective than European Canadians. Regarding psychological variables, there was no difference in stoicism and cautiousness between groups, but Chinese participants reported greater pain catastrophizing. Mediational analysis indicated that pain catastrophizing mediated the group differences in SF-MPQ-Affective score. The implications of the findings and future research were discussed. The study found ethnic differences in cold-pressor responses, in which Chinese undergraduates reported higher levels of pain compared to their Euro-Canadian counterparts. The finding that pain catastrophizing mediated the ethnic difference in SF-MPQ-Affective scores indicated the importance of examining the role of catastrophizing in pain reports from Chinese and Euro-Canadian patients. Crown Copyright © 2010. Published by Elsevier Inc. All rights reserved.
Electronic gaming as pain distraction
Jameson, Eleanor; Trevena, Judy; Swain, Nic
2011-01-01
The current study investigated whether active distraction reduces participants’ experience of pain more than passive distraction during a cold pressor task. In the first experiment, 60 participants were asked to submerge their hand in cold (2°C) water for as long as they could tolerate. They did this with no distraction, and then with active (electronic gaming system) and passive (television) distraction, in randomly assigned order. Tolerance time, pain intensity ratings and task absorption ratings were measured for each condition. A second experiment attempted to control for participants’ expectations about the effects of distraction on pain. Forty participants underwent the same experimental procedure, but were given verbal suggestions about the effects of distraction by the experimenter before each distraction condition. Participants in both experiments had a significantly higher pain tolerance and reported less pain with the active distraction compared with passive or no distraction. Participants reported being more absorbed, and were significantly more willing to do the task again when they had the active distraction compared with both passive distraction and no distraction. They also had more enjoyment, less anxiety and greater reduction in pain with active distraction than with passive distraction. There was no effect of suggestion. These experiments offer further support for the use of electronic games as a method of pain control. PMID:21369538
Electronic gaming as pain distraction.
Jameson, Eleanor; Trevena, Judy; Swain, Nic
2011-01-01
The current study investigated whether active distraction reduces participants' experience of pain more than passive distraction during a cold pressor task. In the first experiment, 60 participants were asked to submerge their hand in cold (2°C) water for as long as they could tolerate. They did this with no distraction, and then with active (electronic gaming system) and passive (television) distraction, in randomly assigned order. Tolerance time, pain intensity ratings and task absorption ratings were measured for each condition. A second experiment attempted to control for participants' expectations about the effects of distraction on pain. Forty participants underwent the same experimental procedure, but were given verbal suggestions about the effects of distraction by the experimenter before each distraction condition. Participants in both experiments had a significantly higher pain tolerance and reported less pain with the active distraction compared with passive or no distraction. Participants reported being more absorbed, and were significantly more willing to do the task again when they had the active distraction compared with both passive distraction and no distraction. They also had more enjoyment, less anxiety and greater reduction in pain with active distraction than with passive distraction. There was no effect of suggestion. These experiments offer further support for the use of electronic games as a method of pain control.
Klinger, Regine; Kothe, Ralph; Schmitz, Julia; Kamping, Sandra; Flor, Herta
2017-10-01
This study tested the experimental placebo effect in a group of chronic pain patients. Forty-eight patients having chronic back pain participated in a randomized clinical trial that tested the efficacy of a sham opioid solution (NaCl) compared with an alleged neutral, completely inactive solution (NaCl). We shaped the placebo effect by 2 interventions: verbal instruction and conditioning. The patients were either told that the "solution reduces pain and improves physical capacity" or the "solution is neutral, a placebo." Half of each group was additionally conditioned (coupling solution with reduced experimental pain), yielding 4 subgroups with 12 participants each. Outcome measures were as follows: the patients' clinical back pain ratings and acute pain ratings (both examined by numerical rating scale 0-10) and self-rated functional capacity (0%-100%; time required for the exercise). Expected pain relief before and after solution intake was also assessed. The inactive solution (NaCl), when presented as an effective treatment (sham "opioid" solution), induced placebo analgesia as evident in lower ratings of the patients' clinical back pain (F(3.12,144.21) = 25.05, P < 0.001), acute pain ratings (F(1.99,87.40) = 18.12, P < 0.01), and time needed to complete a series of daily activities exercises (F(1,44) = 8.51, P < 0.01) as well as increased functional capacity (F(1,44.00) = 19.42, P < 0.001). The 2 manipulations (instruction and conditioning) changed pain expectations, and they were maintained in both sham opioid groups. The results suggest that it may be clinically useful to explicitly integrate placebo analgesia responses into pain management.
Hatton, Anna L; Hug, François; Chen, Sarah H; Reid, Christine; Sorensen, Nicole A; Tucker, Kylie
2016-10-01
Middle-aged adults with painful hip conditions show balance impairments that are consistent with an increased risk of falls. Pathological changes at the hip, accompanied by pain, may accelerate pre-existing age-related balance deficits present in midlife. To consider the influence of pain alone, we investigated the effects of acute experimental hip muscle pain on dynamic single-limb balance in middle-aged adults. Thirty-four healthy adults aged 40-60 years formed two groups (Group-1: n=16; Group-2: n=18). Participants performed four tasks: Reactive Sideways Stepping (ReactSide); Star Excursion Balance Test (SEBT); Step Test; Single-Limb Squat; before and after an injection of hypertonic saline into the right gluteus medius muscle (Group-1) or ∼5min rest (Group-2). Balance measures included the range and standard deviation of centre of pressure (CoP) movement in mediolateral and anterior-posterior directions, and CoP total path velocity (ReactSide, Squat); reach distance (SEBT); and number of completed steps (Step Test). Data were assessed using three-way analysis of variance. Motor outcomes were altered during the second repetition of tasks irrespective of exposure to experimental hip muscle pain or rest, with reduced SEBT anterior reach (-1.2±4.1cm, P=0.027); greater step number during Step Test (1.5±1.7 steps, P<0.001); and slower CoP velocity during Single-Limb Squat (-4.9±9.4mms -1 , P=0.024). Factors other than the presence of pain may play a greater role in balance impairments in middle-aged adults with hip pathologies. Copyright © 2016 Elsevier B.V. All rights reserved.
Age effects on pain thresholds, temporal summation and spatial summation of heat and pressure pain.
Lautenbacher, Stefan; Kunz, Miriam; Strate, Peter; Nielsen, Jesper; Arendt-Nielsen, Lars
2005-06-01
Experimental data on age-related changes in pain perception have so far been contradictory. It has appeared that the type of pain induction method is critical in this context, with sensitivity to heat pain being decreased whereas sensitivity to pressure pain may be even enhanced in the elderly. Furthermore, it has been shown that temporal summation of heat pain is more pronounced in the elderly but it has remained unclear whether age differences in temporal summation are also evident when using other pain induction methods. No studies on age-related changes in spatial summation of pain have so far been conducted. The aim of the present study was to provide a comprehensive survey on age-related changes in pain perception, i.e. in somatosensory thresholds (warmth, cold, vibration), pain thresholds (heat, pressure) and spatial and temporal summation of heat and pressure pain. We investigated 20 young (mean age 27.1 years) and 20 elderly (mean age 71.6 years) subjects. Our results confirmed and extended previous findings by showing that somatosensory thresholds for non-noxious stimuli increase with age whereas pressure pain thresholds decrease and heat pain thresholds show no age-related changes. Apart from an enhanced temporal summation of heat pain, pain summation was not found to be critically affected by age. The results of the present study provide evidence for stimulus-specific changes in pain perception in the elderly, with deep tissue (muscle) nociception being affected differently by age than superficial tissue (skin) nociception. Summation mechanisms contribute only moderately to age changes in pain perception.
2009-01-01
Background Cancer-related pain is common and under-treated. This article describes a study designed to test the effectiveness of a theory-driven, patient-centered coaching intervention to improve cancer pain processes and outcomes. Methods/Design The Cancer Health Empowerment for Living without Pain (Ca-HELP) Study is an American Cancer Society sponsored randomized trial conducted in Sacramento, California. A total of 265 cancer patients with at least moderate pain severity (Worst Pain Numerical Analog Score >=4 out of 10) or pain-related impairment (Likert score >= 3 out of 5) were randomly assigned to receive tailored education and coaching (TEC) or educationally-enhanced usual care (EUC); 258 received at least one follow-up assessment. The TEC intervention is based on social-cognitive theory and consists of 6 components (assess, correct, teach, prepare, rehearse, portray). Both interventions were delivered over approximately 30 minutes just prior to a scheduled oncology visit. The majority of visits (56%) were audio-recorded for later communication coding. Follow-up data including outcomes related to pain severity and impairment, self-efficacy for pain control and for patient-physician communication, functional status and well-being, and anxiety were collected at 2, 6, and 12 weeks. Discussion Building on social cognitive theory and pilot work, this study aims to test the hypothesis that a brief, tailored patient activation intervention will promote better cancer pain care and outcomes. Analyses will focus on the effects of the experimental intervention on pain severity and impairment (primary outcomes); self-efficacy and quality of life (secondary outcomes); and relationships among processes and outcomes of cancer pain care. If this model of coaching by lay health educators proves successful, it could potentially be implemented widely at modest cost. Trial Registration [Clinical Trials Identifier: NCT00283166] PMID:19737424
Sadness enhances the experience of pain and affects pain-evoked cortical activities: an MEG study.
Yoshino, Atsuo; Okamoto, Yasumasa; Onoda, Keiichi; Shishida, Kazuhiro; Yoshimura, Shinpei; Kunisato, Yoshihiko; Demoto, Yoshihiko; Okada, Go; Toki, Shigeru; Yamashita, Hidehisa; Yamawaki, Shigeto
2012-07-01
Pain is a multidimensional phenomenon. Previous psychological studies have shown that a person's subjective pain threshold can change when certain emotions are recognized. We examined this association with magnetoencephalography. Magnetic field strength was recorded with a 306-channel neuromagnetometer while 19 healthy subjects (7 female, 12 male; age range = 20-30 years) experienced pain stimuli in different emotional contexts induced by the presentation of sad, happy, or neutral facial stimuli. Subjects also rated their subjective pain intensity. We hypothesized that pain stimuli were affected by sadness induced by facial recognition. We found: 1) the intensity of subjective pain ratings increased in the sad emotional context compared to the happy and the neutral contexts, and 2) event-related desynchronization of lower beta bands in the right hemisphere after pain stimuli was larger in the sad emotional condition than in the happy emotional condition. Previous studies have shown that event-related desynchronization in these bands could be consistently observed over the primary somatosensory cortex. These findings suggest that sadness can modulate neural responses to pain stimuli, and that brain processing of pain stimuli had already been affected, at the level of the primary somatosensory cortex, which is critical for sensory processing of pain. We found that subjective pain ratings and cortical beta rhythms after pain stimuli are influenced by the sad emotional context. These results may contribute to understanding the broader relationship between pain and negative emotion. Copyright © 2012 American Pain Society. Published by Elsevier Inc. All rights reserved.
Using an experimental model for the study of therapeutic touch.
dos Santos, Daniella Soares; Marta, Ilda Estéfani Ribeiro; Cárnio, Evelin Capellari; de Quadros, Andreza Urba; Cunha, Thiago Mattar; de Carvalho, Emilia Campos
2013-02-01
to verify whether the Paw Edema Model can be used in investigations about the effects of Therapeutic Touch on inflammation by measuring the variables pain, edema and neutrophil migration. this is a pilot and experimental study, involving ten male mice of the same genetic strain and divided into experimental and control group, submitted to the chemical induction of local inflammation in the right back paw. The experimental group received a daily administration of Therapeutic Touch for 15 minutes during three days. the data showed statistically significant differences in the nociceptive threshold and in the paw circumference of the animals from the experimental group on the second day of the experiment. the experiment model involving animals can contribute to study the effects of Therapeutic Touch on inflammation, and adjustments are suggested in the treatment duration, number of sessions and experiment duration.
Yip, Y B; Tse, Hing-Min Sonny; Wu, Ka Kalina
2007-02-01
To compare the efficacy of combined transcutaneous acupoint electrical stimulation (TAES) and electromagnetic millimeter wave (EMMW) therapy as an add-on treatment for pain relief and physical functional activity enhancement among adults with sub-acute non-specific spinal pain in either the low back or neck. A non-blinded study with data obtained before, immediate, one week and three months after intervention. The Telehealth Clinic and Community Centre, Hong Kong. Forty-seven subjects with either sub-acute neck or low back pain. Subjects were randomly allocated to either an intervention group (n=23) or a control group (n=24). These groups were then divided into subgroups according to the site of their spinal pain-neck or back. The intervention group had eight treatments over a three-week period of TAES and EMMW. Changes from baseline to the end of treatment were assessed at intervals of one week and three months on either neck or low back pain intensity [by Visual Analogue Scale (VAS)]; stiffness level; stress level; neck or low back lateral flexion and forward flexion in cm, and interference with daily activities. The baseline VAS scores for the intervention and control groups were 5.34 and 5.18 out of 10, respectively (P value=0.77). At the one week and three month assessments, there were no significant differences between the groups-VAS (P value=0.09 and 0.27, respectively). A further subgroup of chronic pain sufferers (n=31) was identified and these had significantly reduced pain intensity at the one week assessment (P value=0.04) but this was not sustained at post three months after treatment (P value=0.15). Improvements in stiffness level, stress level, and functional disability level in the intervention group were not significant. Our study shows that there was a reduction in pain intensity, stress and stiffness level immediately after the eight sessions of treatment (TAES and EMMW), though the effect is not sustained after a week. No pain relief was found
Multiethnic differences in responses to laboratory pain stimuli among children.
Lu, Qian; Zeltzer, Lonnie; Tsao, Jennie
2013-08-01
A growing body of literature suggests ethnic differences in experimental pain. However, these studies largely focus on adults and the comparison between Caucasians and African Americans. The primary aim of this study is to determine ethnic differences in laboratory-induced pain in a multiethnic child sample. Participants were 214 healthy children (mean age = 12.7, SD = 3.0 years). Ninety-eight Caucasian, 58 Hispanic, 34 African American, and 24 Asian children were exposed to four trials of pressure and radiant heat pain stimuli. Pain responses were assessed with self-report measures (i.e., pain intensity and unpleasantness) and behavioral observation (i.e., pain tolerance). Asians demonstrated more pain sensitivity than Caucasians, who evidenced more pain sensitivity than African Americans and Hispanics. The results hold even after controlling for age, sex, SES, and experimenter's ethnicity. Asians also showed higher anticipatory anxiety compared with other ethnic groups. Anticipatory anxiety accounted for some ethnic differences in pain between Asians, Hispanics, and African Americans. By examining response to laboratory pain stimuli in children representing multiple ethnicities, an understudied sample, the study reveals unique findings compared to the existing literature. These findings have implications for clinicians who manage acute pain in children from diverse ethnic backgrounds. Future investigations should examine mechanisms that account for ethnic differences in pain during various developmental stages. PsycINFO Database Record (c) 2013 APA, all rights reserved.
Sex differences and hormonal modulation of deep tissue pain
Traub, Richard J.; Ji, Yaping
2013-01-01
Women disproportionately suffer from many deep tissue pain conditions. Experimental studies show that women have lower pain thresholds, higher pain ratings and less tolerance to a range of painful stimuli. Most clinical and epidemiological reports suggest female gonadal hormones modulate pain for some, but not all, conditions. Similarly, animal studies support greater nociceptive sensitivity in females in many deep tissue pain models. Gonadal hormones modulate responses in primary afferents, dorsal horn neurons and supraspinal sites, but the direction of modulation is variable. This review will examine sex differences in deep tissue pain in humans and animals focusing on the role of gonadal hormones (mainly estradiol) as an underlying component of the modulation of pain sensitivity. PMID:23872333
Schuh-Hofer, Sigrid; Wodarski, Rachel; Pfau, Doreen B; Caspani, Ombretta; Magerl, Walter; Kennedy, Jeffrey D; Treede, Rolf-Detlef
2013-09-01
Sleep disturbances are highly prevalent in chronic pain patients. Understanding their relationship has become an important research topic since poor sleep and pain are assumed to closely interact. To date, human experimental studies exploring the impact of sleep disruption/deprivation on pain perception have yielded conflicting results. This inconsistency may be due to the large heterogeneity of study populations and study protocols previously used. In addition, none of the previous studies investigated the entire spectrum of nociceptive modalities. To address these shortcomings, a standardized comprehensive quantitative sensory protocol was used in order to compare the somatosensory profile of 14 healthy subjects (6 female, 8 male, 23.5 ± 4.1 year; mean ± SD) after a night of total sleep deprivation (TSD) and a night of habitual sleep in a cross-over design. One night of TSD significantly increased the level of sleepiness (P<0.001) and resulted in higher scores of the State Anxiety Inventory (P<0.01). In addition to previously reported hyperalgesia to heat (P<0.05) and blunt pressure (P<0.05), study participants developed hyperalgesia to cold (P<0.01) and increased mechanical pain sensitivity to pinprick stimuli (P<0.05) but no changes in temporal summation. Paradoxical heat sensations or dynamic mechanical allodynia were absent. TSD selectively modulated nociception, since detection thresholds of non-nociceptive modalities remained unchanged. Our findings show that a single night of TSD is able to induce generalized hyperalgesia and to increase State Anxiety scores. In the future, TSD may serve as a translational pain model to elucidate the pathomechanisms underlying the hyperalgesic effect of sleep disturbances. Copyright © 2013 International Association for the Study of Pain. Published by Elsevier B.V. All rights reserved.
Briggs, Emma V; Battelli, Daniele; Gordon, David; Kopf, Andreas; Ribeiro, Sofia; Puig, Margarita M; Kress, Hans G
2015-08-10
Unrelieved pain is a substantial public health concern necessitating improvements in medical education. The Advancing the Provision of Pain Education and Learning (APPEAL) study aimed to determine current levels and methods of undergraduate pain medicine education in Europe. Using a cross-sectional design, publicly available curriculum information was sought from all medical schools in 15 representative European countries in 2012-2013. Descriptive analyses were performed on: the provision of pain teaching in dedicated pain modules, other modules or within the broader curriculum; whether pain teaching was compulsory or elective; the number of hours/credits spent teaching pain; pain topics; and teaching and assessment methods. Curriculum elements were publicly available from 242 of 249 identified schools (97%). In 55% (133/242) of schools, pain was taught only within compulsory non-pain-specific modules. The next most common approaches were for pain teaching to be provided wholly or in part via a dedicated pain module (74/242; 31%) or via a vertical or integrated approach to teaching through the broader curriculum, rather than within any specific module (17/242; 7%). The curricula of 17/242 schools (7%) showed no evidence of any pain teaching. Dedicated pain modules were most common in France (27/31 schools; 87%). Excluding France, only 22% (47/211 schools) provided a dedicated pain module and in only 9% (18/211) was this compulsory. Overall, the median number of hours spent teaching pain was 12.0 (range 4-56.0 h; IQR: 12.0) for compulsory dedicated pain modules and 9.0 (range 1.0-60.0 h; IQR: 10.5) for other compulsory (non-pain specific) modules. Pain medicine was principally taught in classrooms and assessed by conventional examinations. There was substantial international variation throughout. Documented pain teaching in many European medical schools falls far short of what might be expected given the prevalence and public health burden of pain. Published by the
The effect of traditional wet cupping on shoulder pain and neck pain: A pilot study.
Arslan, Müzeyyen; Gökgöz, Nurcan; Dane, Şenol
2016-05-01
Wet cupping therapy (WCT) is a traditional complementary method recommended to decrease the symptoms of a lot of diseases and used in the treatment of pain syndromes. In this pilot study, the possible effects of wet cupping therapy on nonspecific neck and upper shoulder pain were investigated. Sixty one eligible volunteer participants with nonspecific neck and upper shoulder pain for at least 3 months were allocated. The Numeric Rating Scale (NRS) was used to assess pain scores. Pain scores were recorded before and after wet cupping therapy. The mean scores of neck pain in study group were 7.02 (SD = 1.8) before and 3.70 (SD = 2.2) after cupping therapy. The decrease of pain scores between pre- and post-test was statistically significant (p < 0.05). It can be stated that WCT has potential therapeutic effect in nonspecific neck and upper shoulder pain. Future full-scale randomized controlled trials will be needed to provide firm evidence of the effectiveness of this intervention. Copyright © 2016 Elsevier Ltd. All rights reserved.
Yilmaz Yelvar, Gul Deniz; Çırak, Yasemin; Dalkılınç, Murat; Parlak Demir, Yasemin; Guner, Zeynep; Boydak, Ayşenur
2017-02-01
According to literature, virtual reality was found to reduce pain and kinesiophobia in patients with chronic pain. The purpose of the study was to investigate short-term effect of the virtual reality on pain, function, and kinesiophobia in patients with subacute and chronic non-specific low-back pain METHODS: This randomised controlled study in which 44 patients were randomly assigned to the traditional physiotherapy (control group, 22 subjects) or virtual walking integrated physiotherapy (experimental group, 22 subjects). Before and after treatment, Visual Analog Scale (VAS), TAMPA Kinesiophobia Scale (TKS), Oswestry Disability Index (ODI), Nottingham Health Profile (NHP), Timed-up and go Test (TUG), 6-Minute Walk Test (6MWT), and Single-Leg Balance Test were assessed. The interaction effect between group and time was assessed by using repeated-measures analysis of covariance. After treatment, both groups showed improvement in all parameters. However, VAS, TKS, TUG, and 6MWT scores showed significant differences in favor of the experimental group. Virtual walking integrated physiotherapy reduces pain and kinesiophobia, and improved function in patients with subacute and chronic non-specific low-back pain in short term.
The effect of the type of pain on the accuracy of memory of pain and affect.
Bąbel, P; Pieniążek, L; Zarotyński, D
2015-03-01
Memory of chronic, acute and experimental pain may be inaccurate, but the research findings are inconsistent. The main aim of the study was to compare the memory of three types of pain and their associated affect. A total of 140 women, who gave birth by vaginal delivery or Caesarean section, or underwent gynaecological surgery, participated in the study. Before childbirth or surgery, the women rated their anxiety about the pain they would experience. Between 24 and 48 h after childbirth or surgery, they rated the intensity and unpleasantness of the pain, and their positive and negative affect. Either 3 or 6 months later, the participants recalled the pain and affect they had felt. The study found that the type of pain had an effect on memory of pain and affect. Surgery led to an overestimation of all but one of the recalled variables. Participants who gave birth by Caesarean section were the most accurate at recalling pain and affect. Memories of pain and affect were most variable in participants who gave birth by vaginal delivery. The three groups of participants differed in terms of the predictors of recalled pain intensity and unpleasantness, and the proportion of variance predicted by the same independent variables. The results of the current study suggest that memory of pain and affect is influenced by the meaning and affective value of the pain experience. This may help us to understand why the previous research on the memory of pain were so diverse. © 2014 European Pain Federation - EFIC®
Grosen, Kasper; Vase, Lene; Pilegaard, Hans K.; Pfeiffer-Jensen, Mogens; Drewes, Asbjørn M.
2014-01-01
Background Variability in patients' postoperative pain experience and response to treatment challenges effective pain management. Variability in pain reflects individual differences in inhibitory pain modulation and psychological sensitivity, which in turn may be clinically relevant for the disposition to acquire pain. The aim of this study was to investigate the effects of conditioned pain modulation and situational pain catastrophizing on postoperative pain and pain persistency. Methods Preoperatively, 42 healthy males undergoing funnel chest surgery completed the Spielberger's State-Trait Anxiety Inventory and Beck's Depression Inventory before undergoing a sequential conditioned pain modulation paradigm. Subsequently, the Pain Catastrophizing Scale was introduced and patients were instructed to reference the conditioning pain while answering. Ratings of movement-evoked pain and consumption of morphine equivalents were obtained during postoperative days 2–5. Pain was reevaluated at six months postoperatively. Results Patients reporting persistent pain at six months follow-up (n = 15) were not significantly different from pain-free patients (n = 16) concerning preoperative conditioned pain modulation response (Z = 1.0, P = 0.3) or level of catastrophizing (Z = 0.4, P = 1.0). In the acute postoperative phase, situational pain catastrophizing predicted movement-evoked pain, independently of anxiety and depression (β = 1.0, P = 0.007) whereas conditioned pain modulation predicted morphine consumption (β = −0.005, P = 0.001). Conclusions Preoperative conditioned pain modulation and situational pain catastrophizing were not associated with the development of persistent postoperative pain following funnel chest repair. Secondary outcome analyses indicated that conditioned pain modulation predicted morphine consumption and situational pain catastrophizing predicted movement-evoked pain intensity in the acute postoperative
Meredith, Pamela Joy
2013-04-01
Theoretical and empirical evidence suggests that adult attachment and pain-related variables are predictably and consistently linked, and that understanding these links may guide pain intervention and prevention efforts. In general, insecure attachment has been portrayed as a risk factor, and secure attachment as a protective factor, for people with chronic pain conditions. In an effort to better understand the relationships among attachment and pain variables, these links have been investigated in pain-free samples using induced-pain techniques. The present paper reviews the available research linking adult attachment and laboratory-induced pain. While the diverse nature of the studies precludes definitive conclusions, together these papers offer support for associations between insecure attachment and a more negative pain experience. The evidence presented in this review highlights areas for further empirical attention, as well as providing some guidance for clinicians who may wish to employ preventive approaches and other interventions informed by attachment theory.
Starkweather, Angela R; Lyon, Debra E; Kinser, Patricia; Heineman, Amy; Sturgill, Jamie L; Deng, Xiaoyan; Siangphoe, Umaporn; Elswick, R K; Greenspan, Joel; Dorsey, Susan G
2016-07-01
Persistent low back pain is a significant problem worldwide. Early identification and treatment of individuals at high risk for persistent low back pain have been suggested as strategies to decrease the rate of disability associated with this condition. To examine and compare demographic, pain-related, psychological, and somatosensory characteristics in a cohort of participants with acute low back pain who later went on to experience persistent low back pain or whose pain resolved within the first 6 weeks after initial onset. A descriptive study was conducted among men and women 18-50 years of age who had an acute episode of low back pain. Study questionnaires were administered to collect demographic information and measures of pain, coping, reactivity, mood, work history and satisfaction, and disability. A standardized protocol of quantitative sensory testing was performed on each participant at the painful area of their low back and at a remote site on their arm. The sample consisted of 48 participants, of whom 19 went on to develop persistent low back pain and 29 resolved. Compared to the resolved group, the persistent low back pain group was significantly older and had a lower level of educational attainment, a higher body mass index, and higher mean "least" pain score on the Brief Pain Inventory-Short Form. Significantly higher thermal detection thresholds at the painful and remote sites as well as signs of central sensitivity differentiated the persistent pain group from the resolved group during the acute stage of low back pain. © The Author(s) 2016.
A Preliminary Genome-Wide Association Study of Pain-Related Fear: Implications for Orofacial Pain.
Randall, Cameron L; Wright, Casey D; Chernus, Jonathan M; McNeil, Daniel W; Feingold, Eleanor; Crout, Richard J; Neiswanger, Katherine; Weyant, Robert J; Shaffer, John R; Marazita, Mary L
2017-01-01
Acute and chronic orofacial pain can significantly impact overall health and functioning. Associations between fear of pain and the experience of orofacial pain are well-documented, and environmental, behavioral, and cognitive components of fear of pain have been elucidated. Little is known, however, regarding the specific genes contributing to fear of pain. A genome-wide association study (GWAS; N = 990) was performed to identify plausible genes that may predispose individuals to various levels of fear of pain. The total score and three subscales (fear of minor, severe, and medical/dental pain) of the Fear of Pain Questionnaire-9 (FPQ-9) were modeled in a variance components modeling framework to test for genetic association with 8.5 M genetic variants across the genome, while adjusting for sex, age, education, and income. Three genetic loci were significantly associated with fear of minor pain (8q24.13, 8p21.2, and 6q26; p < 5 × 10 -8 for all) near the genes TMEM65 , NEFM , NEFL , AGPAT4 , and PARK2 . Other suggestive loci were found for the fear of pain total score and each of the FPQ-9 subscales. Multiple genes were identified as possible candidates contributing to fear of pain. The findings may have implications for understanding and treating chronic orofacial pain.
Lumbosacral pain in ballet school students. Pilot study.
Drężewska, Marlena; Śliwiński, Zbigniew
2013-01-01
The unique biomechanical demands placed on ballet students predispose to injury and pain. The aim of this study was to evaluate the prevalence of lumbosacral pain in ballet school students and to identify possible risk factors for the pain. The study group comprised 71 ballet school students, including 45 females and 26 males, aged 15-18 years (mean 16.5 years). In order to identify possible risk factors for pain, a survey was conducted, the angle of sacral bone inclination was measured using a mechanical inclinometer and the BMI was calculated. A VAS scale was used for a subjective assessment of pain intensity. Low back pain was reported by 44 patients (62%). A comparison of sacral inclination angles in a position with the feet placed parallel and in the turnout position showed statistically significant changes in the angle among respondents reporting pain (p <0.05). 1. Compensation in the turnout position by increas ed anterior tilt of the pelvis may increase the risk of low back pain. 2. An angle of sacral bone inclination in turnout above or equal to 30° can increase the intensity of low back pain. 3. A BMI below 18.5 in female ballet school stu dents can increase the risk of lumbosacral pain.
Spinal Disinhibition in Experimental and Clinical Painful Diabetic Neuropathy
Marshall, Andrew G.; Lee-Kubli, Corinne; Azmi, Shazli; Zhang, Michael; Ferdousi, Maryam; Mixcoatl-Zecuatl, Teresa; Petropoulos, Ioannis N.; Ponirakis, Georgios; Fineman, Mark S.; Fadavi, Hassan; Frizzi, Katie; Tavakoli, Mitra; Jolivalt, Corinne G.; Boulton, Andrew J.M.; Efron, Nathan; Calcutt, Nigel A.
2017-01-01
Impaired rate-dependent depression (RDD) of the Hoffman reflex is associated with reduced dorsal spinal cord potassium chloride cotransporter expression and impaired spinal γ-aminobutyric acid type A receptor function, indicative of spinal inhibitory dysfunction. We have investigated the pathogenesis of impaired RDD in diabetic rodents exhibiting features of painful neuropathy and the translational potential of this marker of spinal inhibitory dysfunction in human painful diabetic neuropathy. Impaired RDD and allodynia were present in type 1 and type 2 diabetic rats but not in rats with type 1 diabetes receiving insulin supplementation that did not restore normoglycemia. Impaired RDD in diabetic rats was rapidly normalized by spinal delivery of duloxetine acting via 5-hydroxytryptamine type 2A receptors and temporally coincident with the alleviation of allodynia. Deficits in RDD and corneal nerve density were demonstrated in patients with painful diabetic neuropathy compared with healthy control subjects and patients with painless diabetic neuropathy. Spinal inhibitory dysfunction and peripheral small fiber pathology may contribute to the clinical phenotype in painful diabetic neuropathy. Deficits in RDD may help identify patients with spinally mediated painful diabetic neuropathy who may respond optimally to therapies such as duloxetine. PMID:28202580
Beyond the traditional definition of breakthrough pain: an observational study.
Gatti, Antonio; Gentili, Marta; Iorno, Vittorio; Mammucari, Massimo; Tufaro, Giuseppe; Lazzari, Marzia; Sabato, Alessandro Fabrizio
2013-03-01
Breakthrough pain (BTP) is traditionally defined as a transitory pain flare in opioid-treated patients with chronic background pain. This definition has, however, been challenged in recent years. This study aimed to analyze BTP prevalence in different pain conditions. This was a prospective, non-interventional, observational study conducted from June to September 2011 in two Italian pain treatment reference centres. Consecutive patients aged >18 years with oncological or non-oncological pain were eligible for this study; background pain was acute/ subacute (<3 months) or chronic (>3 months). The characteristics of pain were evaluated by means of a structured interview by physicians, and patients were asked to complete a dedicated clinical study form. The following outcomes were assessed: chronic pain duration (in patients with chronic pain), BTP prevalence, and number and severity of daily BTP episodes. All outcomes were assessed in four populations of patients with: (a) chronic oncological pain; (b) chronic non-oncological pain; (c) non-chronic oncological pain; (d) non-chronic non-oncological pain. The correlation between BTP and gender was also investigated. Of 1,270 patients with chronic pain, 1,086 had non-oncological pain (85.5%). Most patients (68.6%) with non-oncological pain were female (P = 0.001). Pain duration was significantly longer in non-oncological pain versus oncological pain groups (P = 0.002). BTP prevalence was lower in non-oncological patients (P < 0.001). No differences were reported in terms of number and severity of daily BTP episodes. BTP was more frequent in females with non-oncological pain (P = 0.04). Females had a significantly higher pain severity (P = 0.02) than males. BTP is frequently reported in patients who do not have BTP according to the traditional definition. BTP frequency and severity is similar in oncological and non-oncological pain.
Heathcote, L C; Lau, J Y F; Mueller, S C; Eccleston, C; Fox, E; Bosmans, M; Vervoort, T
2017-02-01
Pain is common and can be debilitating in childhood. Theoretical models propose that attention to pain plays a key role in pain outcomes, however, very little research has investigated this in youth. This study examined how anxiety-related variables and attention control interacted to predict children's attention to pain cues using eye-tracking methodology, and their pain tolerance on the cold pressor test (CPT). Children aged 8-17 years had their eye-gaze tracked whilst they viewed photographs of other children displaying painful facial expressions during the CPT, before completing the CPT themselves. Children also completed self-report measures of anxiety and attention control. Findings indicated that anxiety and attention control did not impact children's initial fixations on pain or neutral faces, but did impact how long they dwelled on pain versus neutral faces. For children reporting low levels of attention control, higher anxiety was associated with less dwell time on pain faces as opposed to neutral faces, and the opposite pattern was observed for children with high attention control. Anxiety and attention control also interacted to predict pain outcomes. For children with low attention control, increasing anxiety was associated with anticipating more pain and tolerating pain for less time. This is the first study to examine children's attention to pain cues using eye-tracking technology in the context of a salient painful experience. Data suggest that attention control is an important moderator of anxiety on multiple outcomes relevant to young people's pain experiences. This study uses eye tracking to study attention to pain cues in children. Attention control is an important moderator of anxiety on attention bias to pain and tolerance of cold pressor pain in youth. © 2016 European Pain Federation - EFIC®.
Landmark, Tormod; Dale, Ola; Romundstad, Pål; Woodhouse, Astrid; Kaasa, Stein; Borchgrevink, Petter C
2018-05-13
Epidemiological studies of chronic pain frequently report high prevalence estimates. However, there is little information about the development and natural course of chronic pain. We followed a random sample of participants from a population-based study (HUNT 3) with annual measures over four years. Among those without chronic pain at baseline, the probability of developing moderate to severe chronic pain (cumulative incidence) during the first year was 5%, a pain status that was maintained among 38% at the second follow-up. The probability of developing chronic pain diminished substantially for those who maintained a status of no chronic pain over several years. Subjects with moderate to severe chronic pain at baseline had an 8% probability of recovery into no chronic pain, a status that was maintained for 52% on the second follow-up. The probability of recovery diminished substantially as a status of chronic pain was prolonged for several years. Pain severity, widespread pain, pain catastrophizing, depression and sleep were significant predictors of future moderate to severe chronic pain, both among subjects with and without chronic pain at baseline. These findings suggest that the prognosis is fairly good after a new onset of chronic pain. When the pain has lasted for several years, the prognosis becomes poor. The same social and psychological factors predict new onset and the prognosis of chronic pain. This article is protected by copyright. All rights reserved. This article is protected by copyright. All rights reserved.
[Mechanism of pain sensation].
Gyulaházi, Judit
2009-11-15
Pain, as subjective content of consciousness, is an essential attention-calling sign that helps to survive. Pain relieve is obligatory for every physician, thus, its individual appearance can make the analgesia difficult to carry out. The improving neuroimaging techniques allow understanding the development of pain sensation. Through the 24 articles on the PubMed found with keywords 'pain' and 'neuroimaging', we review here the parts of the pain neuron matrix, their tasks and the assumed mechanism of the acute pain sensation. The mechanism of the individual pain sensation is illustrated by the view of the modular function of the medial part of the pain matrix. Experimental results of empathic pain suggest that pain sensation may occur without real damage of the tissues, as well. The pain network plays main role in chronic pain.
Smiling in Pain: Explorations of Its Social Motives
Prkachin, Kenneth; Lautenbacher, Stefan
2013-01-01
Studies of facial responses during experimental and clinical pain have revealed a surprising phenomenon, namely, that a considerable number of individuals respond with a smile. So far, it is not known why smiling occurs during pain. It is possible that the “smile of pain” is socially motivated (e.g., reinforcing social bonds while undergoing an unpleasant experience). The present studies were conducted in an attempt to address the role of social motives in smiling during pain. In two studies, we varied the quantitative (level of sociality) and qualitative (properties of the relationship between interactants) components of the situations in which participants received painful stimulation. Participants' faces were video-recorded and the occurrence of smiling was assessed. The occurrence of smiling differed depending on stimulus intensity and the properties of the relationship between interactants. Smiling occurred more often during the painful compared to nonpainful stimulation. Whereas the presence of a stranger (experimenter) reduced the smiling behavior, the presence of an intimate other increased it. Slight variations in the level of sociality, however, had no effect on the degree of smiling. Social motives possibly aimed at strengthening social bonds and thus ensuring social support appear to underlie smiling during pain. PMID:24236233
The role of trait mindfulness in the pain experience of adolescents.
Petter, Mark; Chambers, Christine T; McGrath, Patrick J; Dick, Bruce D
2013-12-01
Trait mindfulness appears to mitigate pain among adult clinical populations and has a unique relationship with pain catastrophizing. However, little is understood about this phenomenon among adolescents. The association between trait mindfulness and pain in both real-world and experimental contexts was examined in a community sample of adolescents. Participants were 198 adolescents who completed measures of trait mindfulness, pain catastrophizing, and pain interference, as well as an interview on day-to-day pain before undergoing an acute experimental pain task. Following the task, they provided ratings of pain intensity and state catastrophizing. Results showed that with regard to day-to-day pains, mindfulness was a significant and unique predictor of pain interference, and this relationship was partially mediated by pain catastrophizing. Mindfulness also had an indirect relationship with experimental pain intensity and tolerance. These associations were mediated by catastrophizing during the pain task. These findings highlight the association between trait mindfulness and both real-world and experimental pain and offer insight into how mindfulness may affect pain among youth. Findings are discussed in the context of current psychological models of pediatric pain and future avenues for research. This article highlights the association between trait mindfulness and pain variables among adolescents in both real-world and experimental pain settings. These findings offer further evidence of the unique relationship between trait mindfulness and pain catastrophizing in affecting pain variables across pain contexts and populations. Copyright © 2013 American Pain Society. Published by Elsevier Inc. All rights reserved.
Antinociceptive Interaction of Tramadol with Gabapentin in Experimental Mononeuropathic Pain.
Miranda, Hugo F; Noriega, Viviana; Prieto, Juan Carlos; Zanetta, Pilar; Castillo, Rodrigo; Aranda, Nicolás; Sierralta, Fernando
2016-08-01
Neuropathic pain is the result of injury to the nervous system, and different animal models have been established to meet the manifestations of neuropathy. The pharmacotherapy for neuropathic pain includes gabapentin and tramadol, but these are only partially effective when given alone. The aim of this study was to assess the antinociceptive interaction between both drugs using the isobolographic analysis and changes of the IL-1β concentration in a mouse model of neuropathic pain (partial sciatic nerve ligation or PSNL). The i.p. administration of gabapentin (5-100 mg/kg) or tramadol (12.5-100 mg/kg) displayed a dose-dependent antinociception in the hot plate assay of PSNL mice, and effects induced by gabapentin with tramadol were synergistic. Administration of gabapentin or tramadol reversed significantly the increase in the concentration of IL-1β induced by PSNL after either 7 or 14 days and their combination was significantly more potent in reversing the elevated concentration of IL-1β. The synergism obtained by the co-administration of gabapentin and tramadol is proposed to result from action on different mechanisms in pain pathways. Gabapentin or tramadol or their combination modulates the expression of pro-inflammatory cytokine, IL-1β, in a model of mice PSNL which could be due to an inhibition of glial function. © 2016 Nordic Association for the Publication of BCPT (former Nordic Pharmacological Society).
Nassif, Hala; Brosset, Nicolas; Guillaume, Marion; Delore-Milles, Emilie; Tafflet, Muriel; Buchholz, Frédéric; Toussaint, Jean-François
2011-12-01
To evaluate a specific workplace intervention for the management of chronic lower back pain among employees working in assembly positions in the automotive industry. Randomized controlled trial. On site at the workplace of a French automotive manufacturer. Subjects (N=75 volunteers) were recruited on site and randomly assigned to either an experimental group (n=37) or a control group (n=38). The experimental group followed a supervised 60-minute session, 3 times per week, of muscle strengthening, flexibility, and endurance training during 2 months. The control group received no direct intervention. Evaluation took place at baseline, 2 months, and 6 months. Pain related parameters were evaluated using validated questionnaires and scales translated into French (Quebec Back Pain Disability Scale, Rolan Morris Disability Questionnaire, Dallas Pain Questionnaire, and the Tampa Scale for Kinesiophobia). Perceived pain intensity was evaluated using the numerical rating scale, and physical outcome measures were evaluated using specific indicators (flexibility, Biering-Sorensen Test, Shirado test). The multivariate analysis of variance, t test, and Wilcoxon signed-rank test were used for statistical analysis. We observed a significant beneficial effect (P<.025) for the experimental group at 2 and 6 months in pain parameters, specific flexibility, and in back functions, and a significant improvement at 6 months in the control group for the perceived pain intensity, anterior flexion, flexibility of quadriceps, and Dallas Pain Questionnaire's work recreational score. An increase in the practice of physical activity outside the workplace was noted in both groups at 2 months but persisted at 6 months for the experimental group. This study reinforces the multiple health benefits of physical activity and physical therapy modalities in the workplace by assisting individuals at risk who have chronic LBP. Copyright © 2011 American Congress of Rehabilitation Medicine. Published by
Pain and anxiety control: an online study guide.
2008-05-01
The Editorial Board of the Journal of Endodontics has developed a literature-based study guide of topical areas related to endodontics. This study guide is intended to give the reader a focused review of the essential endodontic literature and does not cite all possible articles related to each topic. Although citing all articles would be comprehensive, it would defeat the idea of a study guide. This section will cover pain theories and dentin hypersensitivity, referred pain, oral pain not of dental origin, barodontalgia, local anesthetics, long-acting local anesthetics, intrapulpal anesthesia, intraligamentary anesthesia, intraosseous anesthesia, inferior alveolar nerve block anesthesia, Gow-Gates anesthesia technique, Vazirani-Akinosi anesthesia technique, second-division block anesthesia technique, endodontic postoperative pain, effect of occlusal adjustment on endodontic pain, paresthesia associated with periradicular pathosis, analgesics, sedation, and endodontic flare-ups.
Louw, Adriaan; Podalak, Jessie; Zimney, Kory; Schmidt, Stephen; Puentedura, Emilio J
2018-07-01
Pain neuroscience education (PNE) is an educational strategy aimed at teaching people more about pain from a neurobiological and neurophysiological perspective. Current best-evidence provides strong support for PNE to positively influence pain ratings, dysfunctions, fear-avoidance and pain catastrophization, limitations in movement, pain knowledge, and healthcare utilization. To date, all PNE studies have been conducted on adult populations. This study set out to explore if an abbreviated PNE lecture to middle school children would result in a positive shift in pain knowledge as well as healthier beliefs regarding pain. One-hundred-and-thirty-three middle school students spanning 5th to 8th grade attended a 30-minute PNE lecture. The primary outcome measures of pain knowledge (neurophysiology of pain questionnaire [NPQ]) and beliefs regarding pain (numeric rating scale) were measured before and immediately after the PNE lecture. Significant improvement in knowledge was found with mean score on NPQ test scores improving from 3.83 (29.5%) pre-PNE to 7.90 (60.8%) post-PNE (p < 0.001), with a large effect size (r = .711). Significant shifts in beliefs were also found in all but one of the pain beliefs questions, with a medium effect size for "you can control how much pain you feel" (p < 0.001; r = 0.354) and large effect size for "your brain decides if you feel pain, not your tissues" (p < 0.001; r = 0.545). This study shows that a 30-minute PNE lecture to middle school children resulted in a significant increase in their knowledge of pain as well various beliefs regarding pain.
Cepeda, M S; Carr, D B; Lau, J; Alvarez, H
2006-04-19
The efficacy of music for the treatment of pain has not been established. To evaluate the effect of music on acute, chronic or cancer pain intensity, pain relief, and analgesic requirements. We searched The Cochrane Library, MEDLINE, EMBASE, PsycINFO, LILACS and the references in retrieved manuscripts. There was no language restriction. We included randomized controlled trials that evaluated the effect of music on any type of pain in children or adults. We excluded trials that reported results of concurrent non-pharmacological therapies. Data was extracted by two independent review authors. We calculated the mean difference in pain intensity levels, percentage of patients with at least 50% pain relief, and opioid requirements. We converted opioid consumption to morphine equivalents. To explore heterogeneity, studies that evaluated adults, children, acute, chronic, malignant, labor, procedural, or experimental pain were evaluated separately, as well as those studies in which patients chose the type of music. Fifty-one studies involving 1867 subjects exposed to music and 1796 controls met inclusion criteria. In the 31 studies evaluating mean pain intensity there was a considerable variation in the effect of music, indicating statistical heterogeneity ( I(2) = 85.3%). After grouping the studies according to the pain model, this heterogeneity remained, with the exception of the studies that evaluated acute postoperative pain. In this last group, patients exposed to music had pain intensity that was 0.5 units lower on a zero to ten scale than unexposed subjects (95% CI: -0.9 to -0.2). Studies that permitted patients to select the music did not reveal a benefit from music; the decline in pain intensity was 0.2 units, 95% CI (-0.7 to 0.2). Four studies reported the proportion of subjects with at least 50% pain relief; subjects exposed to music had a 70% higher likelihood of having pain relief than unexposed subjects (95% CI: 1.21 to 2.37). NNT = 5 (95% CI: 4 to 13). Three
Bair, Eric; Gaynor, Sheila; Slade, Gary D.; Ohrbach, Richard; Fillingim, Roger B.; Greenspan, Joel D.; Dubner, Ronald; Smith, Shad B.; Diatchenko, Luda; Maixner, William
2016-01-01
The classification of most chronic pain disorders gives emphasis to anatomical location of the pain to distinguish one disorder from the other (eg, back pain vs temporomandibular disorder [TMD]) or to define subtypes (eg, TMD myalgia vs arthralgia). However, anatomical criteria overlook etiology, potentially hampering treatment decisions. This study identified clusters of individuals using a comprehensive array of biopsychosocial measures. Data were collected from a case–control study of 1031 chronic TMD cases and 3247 TMD-free controls. Three subgroups were identified using supervised cluster analysis (referred to as the adaptive, pain-sensitive, and global symptoms clusters). Compared with the adaptive cluster, participants in the pain-sensitive cluster showed heightened sensitivity to experimental pain, and participants in the global symptoms cluster showed both greater pain sensitivity and greater psychological distress. Cluster membership was strongly associated with chronic TMD: 91.5% of TMD cases belonged to the pain-sensitive and global symptoms clusters, whereas 41.2% of controls belonged to the adaptive cluster. Temporomandibular disorder cases in the pain-sensitive and global symptoms clusters also showed greater pain intensity, jaw functional limitation, and more comorbid pain conditions. Similar results were obtained when the same methodology was applied to a smaller case–control study consisting of 199 chronic TMD cases and 201 TMD-free controls. During a median 3-year follow-up period of TMD-free individuals, participants in the global symptoms cluster had greater risk of developing first-onset TMD (hazard ratio = 2.8) compared with participants in the other 2 clusters. Cross-cohort predictive modeling was used to demonstrate the reliability of the clusters. PMID:26928952
Schrepf, Andrew; Bradley, Catherine S.; O'Donnell, Michael; Luo, Yi; Harte, Steven E.; Kreder, Karl; Lutgendorf, Susan
2015-01-01
Background Interstitial Cystitis/Bladder Pain Syndrome (IC/BPS) is a condition characterized by pelvic pain and urinary symptoms. Some IC/BPS patients have pain confined to the pelvic region, while others suffer widespread pain. Inflammatory processes have previously been linked to pelvic pain in IC/BPS, but their association with widespread pain in IC/BPS has not been characterized. Methods Sixty-six women meeting criteria for IC/BPS completed self-report measures of pain as part of the Multidisciplinary Approach to the Study of Chronic Pelvic Pain (MAPP), collected 3 days of saliva for cortisol assays, and provided blood samples. Peripheral blood mononuclear cells (PBMCs) were stimulated with Toll-Like Receptor (TLR) 2 and 4 agonists and cytokines were measured in supernatant; IL-6 was also measured in plasma. Associations between inflammatory variables and the likelihood of endorsing extra-pelvic pain, or the presence of a comorbid syndrome, were tested by logistic regression and General Linear Models, respectively. A subset of patients (n=32) completed Quantitative Sensory Testing. Results A one standard deviation increase in TLR-4 inflammatory response was associated with a 1.59 greater likelihood of endorsing extra-pelvic pain (p = .019). Participants with comorbid syndromes also had higher inflammatory responses to TLR-4 stimulation in PBMCs (p = .016). Lower pressure pain thresholds were marginally associated with higher TLR-4 inflammatory responses (p = .062), and significantly associated with higher IL-6 in plasma (p = .031). Conclusions TLR-4 inflammatory responses in PBMCs are a marker of widespread pain in IC/BPS, and should be explored in other conditions characterized by medically unexplained pain. PMID:25771510
Bauer, Ulrike; Pitzer, Stefan; Schreier, Maria Magdalena; Osterbrink, Jürgen; Alzner, Reinhard; Iglseder, Bernhard
2016-06-17
Communication skills are known to decrease with advancing cognitive impairment. Analgesic treatment in long-term care may be deficient due to the residents' impaired ability to communicate their pain and needs. Undertreated pain frequently leads to rising BPSD in residents with cognitive impairment, resulting in a treatment with antipsychotics. Aim of this study was the analysis of differences in assessment and pharmacological treatment of pain in nursing home residents relative to their cognitive state and ability to articulate pain. Data stems from the baseline of a non-experimental pre-post-study in 12 Austrian nursing homes. Residents' pain prevalence in relation to pain assessment and cognitive decline was assessed, data on medical diagnoses and prescriptions were retrieved from the nursing homes' documentation (n = 425). Residents were first divided into two groups: Residents with MMSE ≥ 18 were selected into group CUS (cognitively unimpaired/slightly impaired), residents with MMSE ≤ 17 were selected into group CI (cognitively moderately to severely impaired). CI residents were then sub-grouped according to their ability to communicate pain via the Verbal Rating Scale (VRS) (i.e. group CI-V, group CI-NV). Pain behavior of CI residents was assessed with a modified German version of PAINAD. Group differences were tested with ANOVA and H-test, 95 % confidence intervals were calculated and associations were tested with log-binomial regression. Pain prevalence in CI residents irrespective of their ability to communicate pain was 80 % and exceeded the CUS group prevalence significantly by 14 %. CI residents had significantly less analgesic prescriptions. Furthermore, CI residents have a significantly higher risk of getting no analgesics when in pain than CUS residents (CI-V: RR =2.6, CI-NV: RR =3.4). Use of antipsychotics was high in all groups (49 - 65 %) with more prescriptions in the cognitively impaired group. Results point toward an
Effect of cryotherapy on arteriovenous fistula puncture-related pain in hemodialysis patients.
P B, Sabitha; Khakha, D C; Mahajan, S; Gupta, S; Agarwal, M; Yadav, S L
2008-10-01
Pain during areteriovenous fistula (AVF) cannulation remains a common problem in hemodialysis (HD) patients. This study was undertaken to assess the effect of cryotherapy on pain due to arteriovenous fistula puncture in hemodialysis patients. A convenience sample of 60 patients (30 each in experimental and control groups) who were undergoing hemodialysis by using AVF, was assessed in a randomized control trial. Hemodialysis patients who met the inclusion criteria, were randomly assigned to experimental and control groups using a randomization table. Objective and subjective pain scoring was done on two consecutive days of HD treatment (with cryotherapy for the experimental and without cryotherapy for the control group). The tools used were a questionnaire examining demographic and clinical characteristics, an observation checklist for assessing objective pain behavior, and a numerical rating scale for subjective pain assessment. Descriptive statistics were used as deemed appropriate. Chi square, two-sample and paired t-tests, the Mann Whitney test, Wilcoxon's signed rank test, the Kruskal Wallis test, and Spearman's and Pearson's correlations were used for inferential statistics. We found that the objective and subjective pain scores were found to be significantly (P = 0.001) reduced within the experimental group with the application of cryotherapy. This study highlights the need for adopting alternative therapies such as cryotherapy for effective pain management in hospital settings.
The importance of communication in the management of postoperative pain.
Sugai, Daniel Y; Deptula, Peter L; Parsa, Alan A; Don Parsa, Fereydoun
2013-06-01
This study investigates the importance of communication in surgery and how delivering preoperative patient education can lead to better health outcomes postoperatively, via promoting tolerable pain scores and minimizing the use of narcotics after surgery. Patients who underwent outpatient surgery were randomly divided into groups to compare the pain scores of those who received preoperative patient education, the experimental group, and those who did not receive any form of patient education, the control group. Two weeks before surgery, the experimental group subjects received oral and written forms of patient education consisting of how the body responds to pain, and how endorphins cause natural analgesia. Moreover, patients were educated on the negative effects narcotics have on endorphin production and activity, as well as mechanisms of non-opioid analgesics. Of the 69 patients in the experimental group, 90% declined a prescription for hydrocodone after receiving preoperative education two weeks prior to surgery. The control group consisted of 66 patients who did not receive preoperative patient education and 100% filled their hydrocodone prescriptions. Patients in both groups were offered and received gabapentin and celecoxib preoperatively for prophylaxis of postoperative pain unless they declined. The control groups were found to have average pain scores significantly greater (P <.05) than the experimental groups and also a significantly longer (P <.005) duration of pain. This study illustrates the power of patient education via oral, written and visual communication, which can serve as an effective means to minimize narcotic analgesia after surgery.
Pain and other symptoms of CRPS can be increased by ambiguous visual stimuli--an exploratory study.
Hall, Jane; Harrison, Simon; Cohen, Helen; McCabe, Candida S; Harris, N; Blake, David R
2011-01-01
Visual disturbance, visuo-spatial difficulties, and exacerbations of pain associated with these, have been reported by some patients with Complex Regional Pain Syndrome (CRPS). We investigated the hypothesis that some visual stimuli (i.e. those which produce ambiguous perceptions) can induce pain and other somatic sensations in people with CRPS. Thirty patients with CRPS, 33 with rheumatology conditions and 45 healthy controls viewed two images: a bistable spatial image and a control image. For each image participants recorded the frequency of percept change in 1 min and reported any changes in somatosensation. 73% of patients with CRPS reported increases in pain and/or sensory disturbances including changes in perception of the affected limb, temperature and weight changes and feelings of disorientation after viewing the bistable image. Additionally, 13% of the CRPS group responded with striking worsening of their symptoms which necessitated task cessation. Subjects in the control groups did not report pain increases or somatic sensations. It is possible to worsen the pain suffered in CRPS, and to produce other somatic sensations, by means of a visual stimulus alone. This is a newly described finding. As a clinical and research tool, the experimental method provides a means to generate and exacerbate somaesthetic disturbances, including pain, without moving the affected limb and causing nociceptive interference. This may be particularly useful for brain imaging studies. Copyright © 2010 European Federation of International Association for the Study of Pain Chapters. Published by Elsevier Ltd. All rights reserved.
Louw, Adriaan; Zimney, Kory; Puentedura, Emilio J; Diener, Ina
2016-07-01
Systematic review of randomized control trials (RCTs) for the effectiveness of pain neuroscience education (PNE) on pain, function, disability, psychosocial factors, movement, and healthcare utilization in individuals with chronic musculoskeletal (MSK) pain. Systematic searches were conducted on 11 databases. Secondary searching (PEARLing) was undertaken, whereby reference lists of the selected articles were reviewed for additional references not identified in the primary search. All experimental RCTs evaluating the effect of PNE on chronic MSK pain were considered for inclusion. Additional Limitations: Studies published in English, published within the last 20 years, and patients older than 18 years. No limitations were set on specific outcome measures. Data were extracted using the participants, interventions, comparison, and outcomes (PICO) approach. Study quality of the 13 RCTs used in this review was assessed by 2 reviewers using the PEDro scale. Narrative summary of results is provided for each study in relation to outcomes measurements and effectiveness. Current evidence supports the use of PNE for chronic MSK disorders in reducing pain and improving patient knowledge of pain, improving function and lowering disability, reducing psychosocial factors, enhancing movement, and minimizing healthcare utilization.
Gong, Caixia; Yan, Miao; Jiang, Fei; Chen, Zehua; Long, Yuan; Chen, Lixian; Zheng, Qian; Shi, Bing
2014-06-01
This study aimed to observe the postoperative pain rate and degree of pain in preschool children with cleft lip and palate, and investigate the effect of nursing intervention on pain relief. A total of 120 hospitalized cases of three- to seven-year-old preschool children with cleft lip and palate were selected from May to October 2011. The subjects were randomly divided into the control group and experimental groups 1, 2, and 3. The control group used conventional nursing methods, experimental group 1 used analgesic drug treatment, experimental group 2 used psychological nursing interventions, and experimental group 3 used both psychological nursing intervention and analgesic drug treatment. After 6, 12, 24, and 48 h, pain self-assessment, pain parent-assessment, and pain nurse-assessment were calculated for the four groups using the pain assessment forms, and their ratings were compared. The postoperative pain rates of the four groups ranged from 50.0% to 73.3%. The difference among the four groups was statistically significant (P < 0.001). The differences among the control group and experimental groups 1 and 2 were not statistically significant (P = 0.871), whereas the differences among experimental group 3 and the other groups were statistically significant (P < 0.001). Postoperative pain in preschool children with cleft lip and palate is common. Psychological nursing intervention with analgesic treatment is effective in relieving postoperative pain.
Effects of flotation-REST on muscle tension pain.
Kjellgren, A; Sundequist, U; Norlander, T; Archer, T
2001-01-01
The purpose of the present study was to investigate whether the floating form of the restricted environmental stimulation technique (REST) may be applied within the field of pain relief. Flotation-REST consists of a procedure whereby an individual is immersed in a tank filled with water of an extremely high salt concentration. Thirty-seven patients (14 men and 23 women) suffering from chronic pain consisting of aching muscles in the neck and back area participated in the study. They were randomly assigned to either a control group (17 participants) or an experimental group (20 participants). The experimental group received nine opportunities to use the flotation-REST technique in the water tank over a three-week period. The results indicated that the most severe perceived pain intensity was significantly reduced, whereas low perceived pain intensity was not influenced by the floating technique. Further, the results indicated that circulating levels of the noradrenaline metabolite 3-methoxy-4-hydroxyphenylethyleneglycol were reduced significantly in the experimental group but not in the control group following treatment, whereas endorphin levels were not affected by flotation. Flotation-REST treatment also elevated the participants' optimism and reduced the degree of anxiety or depression; at nighttime, patients who underwent flotation fell asleep more easily. The present findings describe possible changes, for the better, in patients presenting with chronic pain complaints.
Hay, Justin L; Okkerse, Pieter; van Amerongen, Guido; Groeneveld, Geert Jan
2016-04-14
Human pain models are useful in the assessing the analgesic effect of drugs, providing information about a drug's pharmacology and identify potentially suitable therapeutic populations. The need to use a comprehensive battery of pain models is highlighted by studies whereby only a single pain model, thought to relate to the clinical situation, demonstrates lack of efficacy. No single experimental model can mimic the complex nature of clinical pain. The integrated, multi-modal pain task battery presented here encompasses the electrical stimulation task, pressure stimulation task, cold pressor task, the UVB inflammatory model which includes a thermal task and a paradigm for inhibitory conditioned pain modulation. These human pain models have been tested for predicative validity and reliability both in their own right and in combination, and can be used repeatedly, quickly, in short succession, with minimum burden for the subject and with a modest quantity of equipment. This allows a drug to be fully characterized and profiled for analgesic effect which is especially useful for drugs with a novel or untested mechanism of action.
'Virtual lesion' in pain research; a study on magnetic stimulation of the primary motor cortex.
Granovsky, Y; Liem, K S; Weissman-Fogel, I; Yarnitsky, D; Chistyakov, A; Sinai, A
2016-02-01
'Virtual lesion' ('VL') is a transient disruption of cortical activity during task performance. It can be induced by single pulses or short trains of transcranial magnetic stimulation (TMS) directed to functionally relevant brain areas. We applied 'VL' methodology of a short train of TMS given on top of experimental tonic pain, expecting to see changes in pain scores. Thirty young healthy subjects (15 women) were assessed with active ('VL') or 'sham' TMS in different sessions, randomly. In each session, 30 sec-long contact heat (47.5 °C, right forearm) was applied stand-alone ('baseline') and with 5 sec-long 10 Hz-TMS over left primary motor cortex (M1) starting at 17 sec of the heat stimulation. Pain scores decreased after 'VL' or 'sham' (p < 0.001). Independently of the type of TMS, pain reduction was stronger in women (p = 0.012). A triple Sex x Stimulation type ('VL' or 'sham') x Condition ('baseline' heat pain vs. heat pain with TMS) interaction (p = 0.027) indicated stronger pain reduction by 'VL' in women (p = 0.008) and not in men (p = 0.78) as compared to 'baseline'. Pain catastrophizing and perceived stress ratings affected the model (p = 0.010 and p < 0.001, respectively), but without sex differences. This study indicates that interactions between cortical excitability of the motor cortex and nociceptive processing may be gender-related. © 2015 European Pain Federation - EFIC®
Granovsky, Yelena; Yarnitsky, David
2013-01-01
Experimental pain stimuli can be used to simulate patients' pain experience. We review recent developments in psychophysical pain testing, focusing on the application of the dynamic tests-conditioned pain modulation (CPM) and temporal summation (TS). Typically, patients with clinical pain of various types express either less efficient CPM or enhanced TS, or both. These tests can be used in prediction of incidence of acquiring pain and of its intensity, as well as in assisting the correct choice of analgesic agents for individual patients. This can help to shorten the commonly occurring long and frustrating process of adjusting analgesic agents to the individual patients. We propose that evaluating pain modulation can serve as a step forward in individualizing pain medicine.
Vlaeyen, J W; de Jong, J; Geilen, M; Heuts, P H; van Breukelen, G
2001-02-01
The aim of this investigation was to examine the effectiveness of a graded exposure in vivo treatment with behavioural experiments as compared to usual graded activity in reducing pain-related fears, catastrophising and pain disability in chronic low back pain patients reporting substantial fear of movement/(re)injury. Included in the study were four consecutive CLBP patients who were referred for outpatient behavioural rehabilitation, and who reported substantial fear of movement/(re)injury (Tampa Scale for Kinesiophobia score>40). A replicated single-case cross-over design was used. After a no-treatment baseline measurement period, the patients were randomly assigned to one of two interventions. In intervention A, patients received the exposure first, followed by graded activity. In intervention B, the sequence of treatment modules was reversed. Sixty-three daily measures of pain-related cognitions and fears were recorded with visual analogue scales. Before and after the treatment, the following measures were taken: pain-related fear, pain catastrophising, pain control and pain disability. Using time series analysis on the daily measures of pain-related cognitions and fears, we found that improvements only occurred during the graded exposure in vivo, and not during the graded activity, irrespective of the treatment order. Analysis of the pre-post treatment differences also revealed that decreases in pain-related fear concurred with decreases in pain catastrophising and pain disability, and in half of the cases an increase in pain control. This study shows that the external validity of exposure in vivo also extends to the subgroup of chronic low back pain patients who report substantial fear of movement/(re)injury.
Attenuation of Persistent Experimental Pancreatitis Pain by a Bradykinin B2 Receptor Antagonist
Chen, Qingmin; Vera-Portocarrero, Louis P.; Ossipov, Michael H.; Vardanyan, Marina; Lai, Josephine; Porreca, Frank
2017-01-01
Objective The role of bradykinin (BK) receptors in activating and sensitizing peripheral nociceptors is well known. Recently, we showed that spinal dynorphin was pronociceptive through direct or indirect BK receptor activation. Here, we explored the potential role of BK receptors in pain associated with persistent pancreatitis in rats. Methods Experimental pancreatitis and abdominal hypersensitivity were induced by intravenous administrations of dibutyltin dichloride (DBTC). [des-Arg9-Leu8]BK (B1 antagonist) and HOE 140 (B2 antagonist) were given by intraperitoneal or intrathecal injection. Dynorphin antiserum was given intrathecally. Reverse transcription–polymerase chain reaction was used to detect spinal mRNA for BK receptors. Results Dibutyltin dichloride–induced pancreatitis upregulated B1 and B2 mRNA in the thoracic dorsal root ganglion and B2, but not B1, in the pancreas. No changes in spinal B1 or B2 mRNA were observed. Intraperitoneal or intrathecal administration of HOE 140 dose dependently abolished DBTC-induced abdominal hypersensitivity, whereas [des-Arg9-Leu8]BK was without effect by either route of administration. Antiserum to dynorphin (intrathecal) abolished DBTC-induced hypersensitivity. Conclusions These results suggest that blockade of peripheral or spinal BK B2 receptors may be an effective approach for diminishing pain associated with pancreatitis. Moreover, it is suggested that spinal dynorphin may maintain pancreatitis pain through direct or indirect activation of BK B2 receptors in the spinal cord. PMID:20531238
Gibson, William; Moss, Penny; Cheng, Tak Ho; Garnier, Alexandre; Wright, Anthony; Wand, Benedict M
2018-03-01
Many factors interact to influence threat perception and the subsequent experience of pain. This study investigated the effect of observing pain (extrinsic threat) and intrinsic threat of pain to oneself on pressure pain threshold (PPT). Forty socially connected pairs of healthy volunteers were threat-primed and randomly allocated to experimental or control roles. An experimental pain modulation paradigm was applied, with non-nociceptive threat cues used as conditioning stimuli. In substudy 1, the extrinsic threat to the experimental participant was observation of the control partner in pain. The control participant underwent hand immersion in noxious and non-noxious water baths in randomized order. Change in the observing participant's PPT from baseline to mid- and postimmersion was calculated. A significant interaction was found for PPT between conditions and test time (F 2,78 = 24.9, P < .005). PPT increased by 23.6% ± 19.3% between baseline and during hand immersion (F 1,39 = 43.7, P < .005). Substudy 2 investigated threat of imminent pain to self. After a 15-minute break, the experimental participant's PPT was retested ("baseline 2"). Threat was primed by suggestion of whole arm immersion in an icier, larger water bath. PPT was tested immediately before anticipated arm immersion, after which the experiment ended. A significant increase in PPT between "baseline 2" and "pre-immersion" was seen (t = -7.6, P = .005), a pain modulatory effect of 25.8 ± 20.7%. Extrinsic and intrinsic threat of pain, in the absence of any afferent input therefore influences pain modulation. This may need to be considered in studies that use noxious afferent input with populations who show dysfunctional pain modulation. The effect on endogenous analgesia of observing another's pain and of threat of pain to oneself was investigated. Extrinsic as well as intrinsic threat cues, in the absence of any afferent input, increased pain thresholds, suggesting
Busch, Volker; Magerl, Walter; Kern, Uwe; Haas, Joachim; Hajak, Göran; Eichhammer, Peter
2012-02-01
Deep and slow breathing (DSB) techniques, as a component of various relaxation techniques, have been reported as complementary approaches in the treatment of chronic pain syndromes, but the relevance of relaxation for alleviating pain during a breathing intervention was not evaluated so far. In order to disentangle the effects of relaxation and respiration, we investigated two different DSB techniques at the same respiration rates and depths on pain perception, autonomic activity, and mood in 16 healthy subjects. In the attentive DSB intervention, subjects were asked to breathe guided by a respiratory feedback task requiring a high degree of concentration and constant attention. In the relaxing DSB intervention, the subjects relaxed during the breathing training. The skin conductance levels, indicating sympathetic tone, were measured during the breathing maneuvers. Thermal detection and pain thresholds for cold and hot stimuli and profile of mood states were examined before and after the breathing sessions. The mean detection and pain thresholds showed a significant increase resulting from the relaxing DSB, whereas no significant changes of these thresholds were found associated with the attentive DSB. The mean skin conductance levels indicating sympathetic activity decreased significantly during the relaxing DSB intervention but not during the attentive DSB. Both breathing interventions showed similar reductions in negative feelings (tension, anger, and depression). Our results suggest that the way of breathing decisively influences autonomic and pain processing, thereby identifying DSB in concert with relaxation as the essential feature in the modulation of sympathetic arousal and pain perception. Wiley Periodicals, Inc.
Louw, Adriaan; Diener, Ina; Butler, David S; Puentedura, Emilio J
2011-12-01
To evaluate the evidence for the effectiveness of neuroscience education (NE) for pain, disability, anxiety, and stress in chronic musculoskeletal (MSK) pain. Systematic searches were conducted on Biomed Central, BMJ.com, CINAHL, the Cochrane Library, NLM Central Gateway, OVID, ProQuest (Digital Dissertations), PsycInfo, PubMed/Medline, ScienceDirect, and Web of Science. Secondary searching (PEARLing) was undertaken, whereby reference lists of the selected articles were reviewed for additional references not identified in the primary search. All experimental studies including randomized controlled trials (RCTs), nonrandomized clinical trials, and case series evaluating the effect of NE on pain, disability, anxiety, and stress for chronic MSK pain were considered for inclusion. Additional limitations: studies published in English, published within the last 10 years, and patients older than 18 years. No limitations were set on specific outcome measures of pain, disability, anxiety, and stress. Data were extracted using the participants, interventions, comparison, and outcomes (PICO) approach. Methodological quality was assessed by 2 reviewers using the Critical Review Form-Quantitative Studies. This review includes 8 studies comprising 6 high-quality RCTs, 1 pseudo-RCT, and 1 comparative study involving 401 subjects. Most articles were of good quality, with no studies rated as poor or fair. Heterogeneity across the studies with respect to participants, interventions evaluated, and outcome measures used prevented meta-analyses. Narrative synthesis of results, based on effect size, established compelling evidence that NE may be effective in reducing pain ratings, increasing function, addressing catastrophization, and improving movement in chronic MSK pain. For chronic MSK pain disorders, there is compelling evidence that an educational strategy addressing neurophysiology and neurobiology of pain can have a positive effect on pain, disability, catastrophization, and
Gender role expectations of pain mediate sex differences in cold pain responses in healthy Libyans.
Alabas, O A; Tashani, O A; Johnson, M I
2012-02-01
Previous studies found a relationship between response to experimentally-induced pain and scores for the gender role expectations of pain (GREP) questionnaire. Findings were similar in individuals from America, Portugal and Israel suggesting that gender role expectations may be universal. The aim of this study was to translate and validate Arabic GREP using Factor Analysis and to investigate if sex differences to cold-pressor pain in healthy Libyan men and women are mediated through stereotypical social constructs of gender role expectations and/or pain-related anxiety. One hundred fourteen university students (58 women) underwent two cycles of cold pressor pain test to measure pain threshold, tolerance, intensity, and unpleasantness. Participants also completed the Arabic GREP questionnaire and the Pain Anxiety Symptom Scale-Short form (PASS-20). It was found that Libyan men had higher pain thresholds and tolerances than women (mean difference, 95% CI: threshold = 4.69 (s), -0.72 to 10.1, p = 0.005; tolerance = 13.46 (s), 0.5-26.4, p = 0.018). There were significant differences between sexes in 6 out of 12 GREP items (p < 0.004 after Bonferonni adjustment). The results of mediational analysis showed that GREP factors were the mediators of the effects of sex on pain threshold (z = -2.452, p = 0.014 for Self Sensitivity); (z = -2.563, p = 0.01, for Self Endurance) and on pain tolerance (z = -2.538, p = 0.01 for Self Endurance). In conclusion, sex differences in response to pain were mediated by gender role expectations of pain but not pain-related anxiety. © 2011 European Federation of International Association for the Study of Pain Chapters.
Pain perception and hypnosis: findings from recent functional neuroimaging studies.
Del Casale, Antonio; Ferracuti, Stefano; Rapinesi, Chiara; Serata, Daniele; Caltagirone, Saverio Simone; Savoja, Valeria; Piacentino, Daria; Callovini, Gemma; Manfredi, Giovanni; Sani, Gabriele; Kotzalidis, Georgios D; Girardi, Paolo
2015-01-01
Hypnosis modulates pain perception and tolerance by affecting cortical and subcortical activity in brain regions involved in these processes. By reviewing functional neuroimaging studies focusing on pain perception under hypnosis, the authors aimed to identify brain activation-deactivation patterns occurring in hypnosis-modulated pain conditions. Different changes in brain functionality occurred throughout all components of the pain network and other brain areas. The anterior cingulate cortex appears to be central in modulating pain circuitry activity under hypnosis. Most studies also showed that the neural functions of the prefrontal, insular, and somatosensory cortices are consistently modified during hypnosis-modulated pain conditions. Functional neuroimaging studies support the clinical use of hypnosis in the management of pain conditions.
Dopamine Precursor Depletion Influences Pain Affect Rather than Pain Sensation
Schulz, Enrico; Baumkötter, Jochen; Ploner, Markus
2014-01-01
Pain is a multidimensional experience, which includes sensory, cognitive, and affective aspects. Converging lines of evidence indicate that dopaminergic neurotransmission plays an important role in human pain perception. However, the precise effects of dopamine on different aspects of pain perception remain to be elucidated. To address this question, we experimentally decreased dopaminergic neurotransmission in 22 healthy human subjects using Acute Phenylalanine and Tyrosine Depletion (APTD). During APTD and a control condition we applied brief painful laser stimuli to the hand, assessed different aspects of pain perception, and recorded electroencephalographic responses. APTD-induced decreases of cerebral dopaminergic activity did not influence sensory aspects of pain perception. In contrast, APTD yielded increases of pain unpleasantness. The increases of unpleasantness ratings positively correlated with effectiveness of APTD. Our finding of an influence of dopaminergic neurotransmission on affective but not sensory aspects of phasic pain suggests that analgesic effects of dopamine might be mediated by indirect effects on pain affect rather than by direct effects on ascending nociceptive signals. These findings contribute to our understanding of the complex relationship between dopamine and pain perception, which may play a role in various clinical pain states. PMID:24760082
Shaikh, Sumaiya; Nagi, Saad S; McGlone, Francis; Mahns, David A
2015-01-01
We recently showed that C low-threshold mechanoreceptors (CLTMRs) contribute to touch-evoked pain (allodynia) during experimental muscle pain. Conversely, in absence of ongoing pain, the activation of CLTMRs has been shown to correlate with a diffuse sensation of pleasant touch. In this study, we evaluated (1) the primary afferent fibre types contributing to positive (pleasant) and negative (unpleasant) affective touch and (2) the effects of tactile stimuli on tonic muscle pain by varying affective attributes and frequency parameters. Psychophysical observations were made in 10 healthy participants. Two types of test stimuli were applied: stroking stimulus using velvet or sandpaper at speeds of 0.1, 1.0 and 10.0 cm/s; focal vibrotactile stimulus at low (20 Hz) or high (200 Hz) frequency. These stimuli were applied in the normal condition (i.e. no experimental pain) and following the induction of muscle pain by infusing hypertonic saline (5%) into the tibialis anterior muscle. These observations were repeated following the conduction block of myelinated fibres by compression of sciatic nerve. In absence of muscle pain, all participants reliably linked velvet-stroking to pleasantness and sandpaper-stroking to unpleasantness (no pain). Likewise, low-frequency vibration was linked to pleasantness and high-frequency vibration to unpleasantness. During muscle pain, the application of previously pleasant stimuli resulted in overall pain relief, whereas the application of previously unpleasant stimuli resulted in overall pain intensification. These effects were significant, reproducible and persisted following the blockade of myelinated fibres. Taken together, these findings suggest the role of low-threshold C fibres in affective and pain processing. Furthermore, these observations suggest that temporal coding need not be limited to discriminative aspects of tactile processing, but may contribute to affective attributes, which in turn predispose individual responses
Sex-Specific Effects of Gender Identification on Pain Study Recruitment.
Mattos Feijó, Larissa; Tarman, Guliz Zeynep; Fontaine, Charlotte; Harrison, Richard; Johnstone, Tom; Salomons, Tim
2018-02-01
Epidemiological, clinical, and laboratory studies show sex differences in pain responses, with women more sensitive to nociceptive stimulation and more vulnerable to long-term pain conditions than men. Because of evidence that men are culturally reinforced for the ability to endure (or under-report) pain, some of these findings might be explained by sociocultural beliefs about gender-appropriate behavior. One potential manifestation of these effects might be differential participation in pain studies, with men adhering to stereotypical masculine roles viewing participation as a way to demonstrate their masculinity. To test this possibility, we assessed gender identification in 137 healthy participants. At the end of the assessment, they were asked if they would like to participate in other research studies. Interested participants were then asked to participate in a study involving administration of pain-evoking stimulation. We compared individuals who agreed to participate in the pain study with those who declined. We observed a significant Sex × Participation interaction in masculine gender identification, such that men (but not women) who agreed to participate identified significantly more with masculine gender. Among masculine gender traits examined, we found that high levels of aggression and competitiveness were the strongest predictors of pain study participation. Our results suggest that men in pain studies might have higher levels of masculine gender identification than the wider male population. Taken together with previous findings of lower levels of pain sensitivity (or reporting) in masculine-identifying male participants, these results suggest an explanation for some of the sex-related differences observed in pain responses. To examine whether sex and gender affect willingness to participate in pain studies, we assessed gender identification in men and women, then attempted to recruit them to participate in a pain study. Men who agree to participate
Imaging study of the painful heel syndrome
DOE Office of Scientific and Technical Information (OSTI.GOV)
Williams, P.L.; Smibert, J.G.; Cox, R.
1987-06-01
A total of 45 patients with the painful heel syndrome without evidence of an associated inflammatory arthritis, seven of whom had pain in both heels, were studied using technetium-99 isotope bone scans and lateral and 45 degrees medial oblique radiographs of both feet. Of the 52 painful heels 31 (59.6%) showed increased uptake of tracer at the calcaneum. Patients with scans showing increased uptake tended to have more severe heel pain and responded more frequently to a local hydrocortisone injection. On plain x-ray, 39 of 52 painful heels (75%) and 24 of the 38 opposite nonpainful heels (63%) showed plantarmore » spurs, compared with five of 63 (7.9%) heels in 59 age- and sex-matched controls. No evidence of stress fractures was seen.« less
Acceptance, cognitive restructuring, and distraction as coping strategies for acute pain.
Kohl, Annika; Rief, Winfried; Glombiewski, Julia Anna
2013-03-01
Little is known about treatment mechanisms underlying acceptance strategies. Acceptance is a strategy that is expected to increase pain tolerance more than distraction, while distraction should lead to lower pain intensity. The effect of cognitive restructuring on experimental pain has not yet been investigated. The present study aimed to explore differential short-term effects of acceptance, distraction, and cognitive restructuring on pain tolerance and intensity. Pain was induced in a sample of 109 female students using a thermode. We conducted analyses of covariance with instruction as the independent variable and posttest scores on pain variables as dependent variables, covarying for pretest scores. In addition, adherence to instructions and credibility of instructions were included as covariates. Acceptance led to a higher increase in pain tolerance than did cognitive restructuring of pain-related thoughts. No differences were detected between either acceptance and distraction or distraction and cognitive restructuring with respect to pain tolerance. Distraction led to lower pain intensity compared to acceptance. Cognitive restructuring did not differ from either acceptance or distraction with respect to pain intensity. As a short-term strategy, cognitive restructuring was not as useful as acceptance in increasing pain tolerance. Further studies should evaluate the preconditions under which different strategies are most effective. This study demonstrated that acceptance was superior to cognitive restructuring in increasing tolerance for experimentally induced pain, but was inferior to distraction with respect to decreasing pain intensity. Knowledge about the types of strategies that are useful in targeting diverse pain-related outcome measures is important for efforts to refine the treatment of chronic pain. Copyright © 2013 American Pain Society. Published by Elsevier Inc. All rights reserved.
The "at-home LLLT" in temporo-mandibular disorders pain control: a pilot study.
Fornaini, C; Pelosi, A; Queirolo, V; Vescovi, P; Merigo, E
2015-03-31
The Temporo-Mandibular Disorders (TMD) are a set of dysfunctional patterns concerning the temporo-mandibular joints (TMJ) and the masticatory muscles; its main symptom is pain, probably caused by inflammatory changes in the synovial membrane, alterations in the bone marrow of the mandibular condyle and impingement and compression. The aim of this preliminary study was to investigate the effectiveness in the TMD pain reduction of a new laser device recently proposed by the commerce that, due to its reduced dimensions and to be a class I laser according the ANSI classification, may be used at home by the patient himself. Twenty-four patients with TMD were randomly selected: the inclusion criteria for the sample was the diagnosis of mono- or bi-lateral TMD, with acute pain restricted to the joint area, associated with the absence of any muscle tenderness during palpation. The patients were randomly assigned to two groups: Group 1 (12 patients): patients receiving real LLLT (experimental group). Group 2 (12 patients): patients receiving inactive laser (placebo group). The treatment was performed once a day for two weeks with an 808 nm diode laser by the patient himself with irradiation of the cutaneous zone corresponding to the TMJ for 15 minutes each side. Each patient was instructed to express its pain in a visual analogue scale (VAS) making a perpendicular line between the two extremes representing the felt pain level. Statistical analysis was realized with GraphPad Instat Software, where P<0.05 was considered significant and P<0.01 very significant. The patient's pain evaluation was expressed in the two study groups before the treatment, 1 week and two weeks after the treatment. The differences between the two groups result extremely significant with p<0.0001 for the comparison of VAS value after 1 and 2 weeks. This study, even if it may be considered such a pilot study, investigated a new way to control the pain in the temporo-mandibular diseases by an at home
Granovsky, Yelena; Yarnitsky, David
2013-01-01
Experimental pain stimuli can be used to simulate patients’ pain experience. We review recent developments in psychophysical pain testing, focusing on the application of the dynamic tests—conditioned pain modulation (CPM) and temporal summation (TS). Typically, patients with clinical pain of various types express either less efficient CPM or enhanced TS, or both. These tests can be used in prediction of incidence of acquiring pain and of its intensity, as well as in assisting the correct choice of analgesic agents for individual patients. This can help to shorten the commonly occurring long and frustrating process of adjusting analgesic agents to the individual patients. We propose that evaluating pain modulation can serve as a step forward in individualizing pain medicine. PMID:24228167
Kielstein, Jan T; Suntharalingam, Mayuren; Perthel, Ronny; Rong, Song; Martens-Lobenhoffer, Jens; Jäger, Kristin; Bode-Böger, Stefanie M; Nave, Heike
2012-03-01
Thermal sensitivity in uraemia is decreased. Non-selective synthetic nitric oxide synthase (NOS) inhibitors significantly attenuate thermal hyperalgesia in preclinical models. The aim of our study was to evaluate the effect of experimental uraemia, which is associated with an increase of the endogenous NOS inhibitor asymmetric dimethylarginine (ADMA), on thermal sensitivity in rats. Furthermore, we intended to study the effect of chronic ADMA infusion alone on thermal sensitivity. Male Sprague-Dawley rats (n = 54), 10 weeks old, weight 370-430 g, were randomly assigned to three groups receiving either (i) isotonic saline or (ii) ADMA via osmotic mini pumps or (iii) underwent 5/6 nephrectomy (Nx). After 14 days, 50% of all animals from all groups underwent thermal sensitivity testing and terminal blood draw. After 28 days, the remaining animals underwent the same procedures. Thermal sensitivity examination was performed by the hot-plate test, measuring time from heat exposition to first paw licking or jumping of the animal. While the median [interquartile range] latency time between heat exposition to first paw licking or jumping of the animal in the NaCl infusion group remained unchanged between Day 14 (8.4 [6.75-11.50] s) and Day 28 (7.35 [6.10-7.90] s) both, ADMA infusion and 5/6 nephrectomy tended to increase the thermal pain threshold at Day 14 (9.25 [6.55-12.18] s) and (9.50 [5.8 ± 11.0] s), respectively, compared to NaCl on Day 14 (8.4 [6.75-11.50] s). This difference became statistical significant at Day 28 where the median latency time in the ADMA group (13.10 [11.85-15.95] s) and in the 5/6 Nx group (13.50 [10.85-17.55] s) were significantly higher than in the NaCl group (7.35 [6.10-7.90] s). Induction of progressive renal failure in rats by 5/6 nephrectomy, which is accompanied by a marked increase of the serum levels of the endogenous NOS inhibitor ADMA, leads to a significantly increased heat pain threshold at 28 days. The sole infusion of ADMA into
Cederbom, Sara; Rydwik, Elisabeth; Söderlund, Anne; Denison, Eva; Frändin, Kerstin; von Heideken Wågert, Petra
2014-01-01
To be an older woman, live alone, have chronic pain, and be dependent on support are all factors that may have an impact on daily life. One way to promote ability in everyday activities in people with pain-related conditions is to use individualized, integrated behavioral medicine in physical therapy interventions. How this kind of intervention works for older women living alone at home, with chronic pain, and dependent on formal care to manage their everyday lives has not been studied. The aim was to explore the feasibility of a study and to evaluate an individually tailored integrated behavioral medicine in physical therapy intervention for the target group of women. The study was a 12-week randomized trial with two-group design. Primary effect outcomes were pain-related disability and morale. Secondary effect outcomes focused on pain-related beliefs, self-efficacy for exercise, concerns of falling, physical activity, and physical performance. In total, 23 women agreed to participate in the study and 16 women completed the intervention. The results showed that the behavioral medicine in physical therapy intervention was feasible. No effects were seen on the primary effect outcomes. The experimental intervention seemed to improve the level of physical activity and self-efficacy for exercise. Some of the participants in both groups perceived that they could manage their everyday life in a better way after participation in the study. Results from this study are encouraging, but the study procedure and interventions have to be refined and tested in a larger feasibility study to be able to evaluate the effects of these kinds of interventions on pain-related disability, pain-related beliefs, self-efficacy in everyday activities, and morale in the target group. Further research is also needed to refine and evaluate effects from individualized reminder routines, support to collect self-report data, safety procedures for balance training, and training of personnel to
Mathur, Vani A; Richeson, Jennifer A; Paice, Judith A; Muzyka, Michael; Chiao, Joan Y
2014-05-01
Racial disparities in pain treatment pose a significant public health and scientific problem. Prior studies have demonstrated that clinicians and nonclinicians are less perceptive of, and suggest less treatment for, the pain of African Americans relative to European Americans. Here we investigate the effects of explicit/implicit patient race presentation, patient race, and perceiver race on pain perception and response. African American and European American participants rated pain perception, empathy, helping motivation, and treatment suggestion in response to vignettes about patients' pain. Vignettes were accompanied by a rapid (implicit) or static (explicit) presentation of an African or European American patient's face. Participants perceived and responded more to European American patients in the implicit prime condition, when the effect of patient race was below the level of conscious regulation. This effect was reversed when patient race was presented explicitly. Additionally, female participants perceived and responded more to the pain of all patients, relative to male participants, and in the implicit prime condition, African American participants were more perceptive and responsive than European Americans to the pain of all patients. Taken together, these results suggest that known disparities in pain treatment may be largely due to automatic (below the level of conscious regulation) rather than deliberate (subject to conscious regulation) biases. These biases were not associated with traditional implicit measures of racial attitudes, suggesting that biases in pain perception and response may be independent of general prejudice. Results suggest that racial biases in pain perception and treatment are at least partially due to automatic processes. When the relevance of patient race is made explicit, however, biases are attenuated and even reversed. We also find preliminary evidence that African Americans may be more sensitive to the pain of others than are
Jensen, Ole Kudsk; Nielsen, Claus Vinther; Sørensen, Joan Solgaard; Stengaard-Pedersen, Kristian
2015-12-03
Cross-sectional studies have shown associations between lumbar degenerative manifestations on magnetic resonance imaging (MRI) and low back pain (LBP). Disc herniations and other degenerative manifestations, however, frequently occur in asymptomatic individuals. The purpose of this cross-sectional study was to analyze for associations between pain intensity and degenerative manifestations and other pain variables in patients for whom prognostic factors have been published previously. Included were 141 consecutive patients with and without radiculopathy, all sick-listed 1-4 months due to low back pain and subsequently examined by MRI of the lumbar spine. Using different methods of grouping the degenerative manifestations, linear regression analyses were performed with the intensity of back + leg pain, back pain and leg pain as dependent variables covering actual pain and pain the preceding 2 weeks. The clinical classification into +/- radiculopathy was established before and independently of the standardised description of MRI findings. Radiculopathy was present in 43 % of the patients. Pain was best explained using rank-ordered degenerative manifestations on MRI. Back pain and leg pain were differently associated, and back pain was less explained than leg pain in the multivariate analyses (15 % vs. 31 % of the variation). Back pain intensity was higher in patients with type 1 Modic changes and in some patients with nerve root touch, but was not associated with disc herniations. Leg pain intensity was well explained by disc herniations causing MRI nerve root compromise and radiculopathy. In patients with radiculopathy, nerve root touch caused as much leg pain as nerve root displacement or compression. High intensity zones and osteophytes were not associated with back pain, but only associated with leg pain in patients with radiculopathy. Tender points explained some of the back pain, and widespread pain explained leg pain in some of the patients without
Pharmacological pain management in chronic pancreatitis
Olesen, Søren S; Juel, Jacob; Graversen, Carina; Kolesnikov, Yuri; Wilder-Smith, Oliver HG; Drewes, Asbjørn M
2013-01-01
Intense abdominal pain is a prominent feature of chronic pancreatitis and its treatment remains a major clinical challenge. Basic studies of pancreatic nerves and experimental human pain research have provided evidence that pain processing is abnormal in these patients and in many cases resembles that seen in neuropathic and chronic pain disorders. An important ultimate outcome of such aberrant pain processing is that once the disease has advanced and the pathophysiological processes are firmly established, the generation of pain can become self-perpetuating and independent of the initial peripheral nociceptive drive. Consequently, the management of pain by traditional methods based on nociceptive deafferentation (e.g., surgery and visceral nerve blockade) becomes difficult and often ineffective. This novel and improved understanding of pain aetiology requires a paradigm shift in pain management of chronic pancreatitis. Modern mechanism based pain treatments taking into account altered pain processing are likely to increasingly replace invasive therapies targeting the nociceptive source, which should be reserved for special and carefully selected cases. In this review, we offer an overview of the current available pharmacological options for pain management in chronic pancreatitis. In addition, future options for pain management are discussed with special emphasis on personalized pain medicine and multidisciplinarity. PMID:24259960
DI Cagno, Alessandra; Minganti, Carlo; Quaranta, Federico; Pistone, Eugenio M; Fagnani, Federica; Fiorilli, Giovanni; Giombini, Arrigo
2017-09-01
The aim of this intervention study was to determine the effects of a new experimental cervical pillow, on symptomatic adults affected by chronic mechanical neck pain. Twelve recreational athletes of both sexes (mean age 40.5 years; range 35-55), affected by grade II chronic mechanical neck pain, were evaluated with a daily diary type of self-report questionnaire, which incorporated an 11-point Numerical Rating Pain Scale, to collect the primary outcome measures of pre- and post-sleep neck pain and with the Neck Pain Disability Scale. Tympanic temperature, heart rate (HR) variability continuous monitoring during sleep, overnight pillow comfort and sleep quality were assessed. Average weekly scores in overall questionnaires, tympanic temperature and the HR low frequency (LF) / high frequency (HF) ratio were significantly lower (P<0.05) after the use of the DM2 pillow than the own pillow. The 80% of participants considered the DM2 "perfectly comfortable" and reported a "good" quality of sleep lying over it. The use of an appropriate pillow is a determinant factor in relieving neck pain, improving LF/HF ratio and enhancing-vagal activity, promoting deeper stages during the sleep. The shape of this pillow maintains an appropriate cervical curvature, reduces intra-disc pressure allowing a better distribution of loads between cervical discs. The round shaped portion of the pillow, facilitates breathing and avoids the narrowing of the airway due to the incorrect position during the sleep. The peculiar material of the DM2 pillow, contributed to lower brain temperature promoting dry heat loss from the head to the pillow, reducing sweating.
Mindfulness meditation-based pain relief: a mechanistic account.
Zeidan, Fadel; Vago, David R
2016-06-01
Pain is a multidimensional experience that involves interacting sensory, cognitive, and affective factors, rendering the treatment of chronic pain challenging and financially burdensome. Further, the widespread use of opioids to treat chronic pain has led to an opioid epidemic characterized by exponential growth in opioid misuse and addiction. The staggering statistics related to opioid use highlight the importance of developing, testing, and validating fast-acting nonpharmacological approaches to treat pain. Mindfulness meditation is a technique that has been found to significantly reduce pain in experimental and clinical settings. The present review delineates findings from recent studies demonstrating that mindfulness meditation significantly attenuates pain through multiple, unique mechanisms-an important consideration for the millions of chronic pain patients seeking narcotic-free, self-facilitated pain therapy. © 2016 New York Academy of Sciences.
Mindfulness meditation–based pain relief: a mechanistic account
Zeidan, Fadel; Vago, David
2016-01-01
Pain is a multidimensional experience that involves sensory, cognitive, and affective factors. The constellation of interactions between these factors renders the treatment of chronic pain challenging and financially burdensome. Further, the widespread use of opioids to treat chronic pain has led to an opioid epidemic characterized by exponential growth in opioid misuse and addiction. The staggering statistics related to opioid use highlight the importance of developing, testing, and validating fast-acting nonpharmacological approaches to treat pain. Mindfulness meditation is a technique that has been found to significantly reduce pain in experimental and clinical settings. The present review delineates findings from recent studies demonstrating that mindfulness meditation significantly attenuates pain through multiple, unique mechanisms—an important consideration for the millions of chronic pain patients seeking narcotic-free, self-facilitated pain therapy. PMID:27398643
Glutamate-evoked jaw muscle pain as a model of persistent myofascial TMD pain?
Castrillon, Eduardo E.; Cairns, Brian E.; Ernberg, Malin; Wang, Kelun; Sessle, Barry; Arendt-Nielsen, Lars; Svensson, Peter
2008-01-01
Objective Compare pain-related measures and psychosocial variables between glutamate-evoked jaw muscle pain in healthy subjects (HS) and patients with persistent myofascial temporomandibular disorder (TMD) pain. Design 47 female HS and 10 female patients with persistent myofascial TMD pain participated. The HS received an injection of glutamate into the masseter muscle to model persistent myofascial TMD pain. Participants filled out a coping strategies questionnaire (CSQ), the symptom checklist 90 (SCL-90) and McGill Pain Questionnaire (MPQ). Pain intensity was assessed on an electronic visual analog scale (VAS). Pain-drawing areas, Numerical Rating Scale (NRS) scores of unpleasantness, pressure pain thresholds (PPT) and tolerance (PPTOL) were measured. Unpaired t-tests and correlation tests were used for analyses. Results The groups were significantly different when comparing the CSQ scores of control, decrease, diverting attention, increase of behavioral activities and somatization. The peak VAS pain, NRS of unpleasantness and MPQ scores were not significantly different between groups, but PPT and PPTOL were significantly lower in the TMD patients. Significant positive correlations were found in the TMD patients between peak VAS pain and CSQ catastrophizing score and SCL-90 somatization. The scores of PPTs and PPTOLs, in patients showed positive correlations with CSQ reinterpreting pain sensations scores and PPTs correlated with CSQ praying/hoping scores. Conclusions Glutamate-evoked pain responses in HS and persistent myofascial TMD pain have similar sensory-discriminative and affective-unpleasantness components but differ in psycho-social features. This study suggests that experimental designs based on glutamate injection into muscle can provide an appropriate model for elucidating persistent myofascial pain conditions. PMID:18313028
Experimental Pain and Opioid Analgesia in Volunteers at High Risk for Obstructive Sleep Apnea
Doufas, Anthony G.; Tian, Lu; Padrez, Kevin A.; Suwanprathes, Puntarica; Cardell, James A.; Maecker, Holden T.; Panousis, Periklis
2013-01-01
Background Obstructive sleep apnea (OSA) is characterized by recurrent nocturnal hypoxia and sleep disruption. Sleep fragmentation caused hyperalgesia in volunteers, while nocturnal hypoxemia enhanced morphine analgesic potency in children with OSA. This evidence directly relates to surgical OSA patients who are at risk for airway compromise due to postoperative use of opioids. Using accepted experimental pain models, we characterized pain processing and opioid analgesia in male volunteers recruited based on their risk for OSA. Methods After approval from the Intitutional Review Board and informed consent, we assessed heat and cold pain thresholds and tolerances in volunteers after overnight polysomnography (PSG). Three pro-inflammatory and 3 hypoxia markers were determined in the serum. Pain tests were performed at baseline, placebo, and two effect site concentrations of remifentanil (1 and 2 µg/ml), an μ-opioid agonist. Linear mixed effects regression models were employed to evaluate the association of 3 PSG descriptors [wake after sleep onset, number of sleep stage shifts, and lowest oxyhemoglobin saturation (SaO2) during sleep] and all serum markers with pain thresholds and tolerances at baseline, as well as their changes under remifentanil. Results Forty-three volunteers (12 normal and 31 with a PSG-based diagnosis of OSA) were included in the analysis. The lower nadir SaO2 and higher insulin growth factor binding protein-1 (IGFBP-1) were associated with higher analgesic sensitivity to remifentanil (SaO2, P = 0.0440; IGFBP-1, P = 0.0013). Other pro-inflammatory mediators like interleukin-1β and tumor necrosis factor-α (TNF-α) were associated with an enhanced sensitivity to the opioid analgesic effect (IL-1β, P = 0.0218; TNF-α, P = 0.0276). Conclusions Nocturnal hypoxemia in subjects at high risk for OSA was associated with an increased potency of opioid analgesia. A serum hypoxia marker (IGFBP-1) was associated with hypoalgesia and
Borckardt, Jeffrey J; Romagnuolo, Joseph; Reeves, Scott T; Madan, Alok; Frohman, Heather; Beam, Will; George, Mark S
2011-06-01
Emerging evidence shows that transcranial direct current stimulation (tDCS), a minimally invasive brain stimulation technique, has analgesic effects in chronic pain patients and in healthy volunteers with experimental pain. No studies have examined the analgesic effects of tDCS immediately after surgical/endoscopic procedures. Endoscopy investigating abdominal pain, especially ERCP, can cause significant postprocedural pain. To test the feasibility, efficacy, and safety of tDCS on post-ERCP pain and analgesia use. Randomized, sham-controlled, pilot study. Tertiary-care medical center. This study involved 21 patients who were hospitalized overnight for ERCP for unexplained right upper quadrant pain. Twenty minutes of real 2.0 mA tDCS or sham (anode over left prefrontal cortex; cathode over gut-representation of right sensory cortex) immediately after ERCP. Pain (visual analogue scale, McGill pain questionnaire, brief pain inventory), patient-controlled analgesia use, adverse events. Real tDCS was associated with 22% less total hydromorphone use, versus sham. The slope of the cumulative patient-controlled analgesia usage curve was significantly steeper in the sham tDCS group (F [2,13] = 15.96; P = .0003). Real tDCS patients reported significantly less pain interference with sleep (t [17] = 3.70; P = .002) and less throbbing pain (t [16] = 2.37; P = .03). Visual analogue scale pain and mood scores (4 hours post-ERCP) suggested a nonsignificant advantage for real tDCS, despite less hydromorphone use. Side effects of tDCS were limited to mild, self-limited tingling, itching, and stinging under electrodes. Small sample size, variability in chronic pain, and chronic opioid use. In this pilot study, tDCS appears to be safe, has minimal side effects, and may reduce postprocedural analgesia requirements and subjective pain ratings. Future studies appear warranted. Copyright © 2011 American Society for Gastrointestinal Endoscopy. Published by Mosby, Inc. All rights reserved.
Matar, Eman M; Arabiat, Diana H; Foster, Mandie J
2016-11-01
This research was undertaken with the purpose of testing two research hypotheses regarding the efficacy of 10% oral glucose solution on procedural pain associated with venepuncture and nasopharyngeal suctioning within three neonatal intensive care units (NICU). The hypotheses were formulated from previous conclusions reached by other researchers highlighting the efficacy of sucrose solutions on neonates' pain responses during minor painful procedures. A quasi-experimental trial utilising a time series design with one group was used. Data from a total of 90 neonates included 60 neonates who underwent a venepuncture and 30 neonates who underwent a nasopharyngeal suctioning procedure for clinical purposes. The neonate's pain response for each procedure was scored using the Neonatal Pain Assessment Scale (NPAS) on two separate occasions over three time periods. The pre-procedural score (T 0 ) when the neonate received no sucrose, the inter-procedural score (T 1 ) when the neonate was given 2ml of 10% glucose solution two minutes before the procedure (intervention group) or where oral glucose was withheld (control group) and the post-procedural score (T 2 ) being at the end of the procedure. The results showed the mean NPAS scores in response to venepuncture or nasopharyngeal suctioning were significantly lower in the intervention group than the control group. This showed that oral glucose (10%) had a positive effect on the pain response during venepuncture and nasopharyngeal suctioning procedures. Copyright © 2015 Elsevier Inc. All rights reserved.
Combined electric and pressure cuff pain stimuli for assessing conditioning pain modulation (CPM).
Tsukamoto, M; Petersen, K K; Mørch, C D; Arendt-Nielsen, L
2017-12-29
Aims Traditionally, conditioning pain modulation (CPM) can be assessed by applying a test stimulus (TS) before and after application of a conditioning stimulus (CS), which is normally applied extra-segmental. Currently, no studies have attempted to apply the TS and CS to the same site using different stimuli modalities. The aim of this study was to evaluate electrical TS and cuff pressure CS applied to the same experimental site for studying CPM. Methods 20 male volunteers participated in this study, which consisted of stimulations applied by a cuff-algometer (NociTech and Aalborg University, Denmark) and current stimulator (Digitimer DS5, UK), through two Ag/AgCl electrodes (Ambu® Neuroline 700, Denmark). The cuff was wrapped around the lower leg and stimulation electrodes were placed under the cuff and to the same location on the contralateral leg. Electrical TS were applied to the non-dominant leg with or without cuff pressure CS on the dominant (CS1) or the same (non-dominant) leg (CS2, electrode under cuff). The subjects were instructed to rate the electrical evoked pain intensity on a 10-cm continuous visual analog scale (VAS, "0" represented "no pain", and "10" represented "maximal pain"). The pain detection threshold (PDT) was defined as "1" on the VAS scale. Results There was no significant deference in PDT for neither CS1 nor CS2. A median split subanalysis on CPM-responders versus CPM-nonresponders to the TS + CS1 combination. Using this grouping, there was significant increase in PDT when comparing TS to TS + CS1 or TS + CS2 (4.0 mA vs 5.6 mA; P < 0.05, 4.0 mA vs 5.1 mA; P < 0.05). Conclusions The study indicates that CPM can be evoked in a subgroup of subjects by applying the electrical test stimulus and cuff pressure conditioning stimuli to the same experimental site.
A study of abdominal pain in children.
Shakya, K N; Dongol, U M S; Khadka, S B
2008-01-01
Pain abdomen is a common pediatric complaint that brings patient to the hospital in Nepal. Knowledge about its etiology and frequency helps in its evaluation and management. The present study was undertaken to find out the causes and their frequency of pain abdomen in Nepali children. Children with pain abdomen presenting at the emergency room and pediatric outpatient department of Kathmandu Medical College, Kathmandu from January, 2006 to December 2007 were clinically evaluated and investigated to find out the causes and frequency of their pain abdomen. The outcomes were tabulated and analyzed for interpretation. Of 444 patients attended, 356 completed investigations and came for follow up. Cause of pain abdomen was apparent in 117 (32.9%) only. 91.5% were medical causes, comprising predominantly of diarrheal diseases (28.3%), infantile colic (9.4%), urinary tract infection (7.7%) and acid peptic disease (6.8%). 8.5% causes were related to surgical conditions, which needed operative management. Secondary or extra-abdominal causes were found in 20 cases (17.1%). Pneumonia (2), functional (5), vulvovaginitis (2) and infantile colic (11) were predominant causes. Our study showed that the causes of pain abdomen in children were predominantly medical. Gastroenteritis was the most frequent cause. Secondary causes, including functional and emotional causes were infrequent. Small percentage needing surgical management formed a diagnostic challenge.
Physiological and behavioural assessment of pain in ruminants: principles and caveats.
Mellor, David J; Stafford, Kevin J
2004-06-01
Pain elicits a range of physiological and behavioural responses. These are commonly used to assess the impact of pain-inducing stimuli on animals, to determine whether or not significant pain is experienced and to devise strategies for alleviating pain. This paper outlines a range of principles and caveats to guide the evaluation of physiological and behavioural responses to painful stimuli, so that they can be better used to minimise pain in the experimental context. Although this advice is based on studies of farm animals responding to painful husbandry practices, it is more generally applicable.
Twycross, Alison M; Chorney, Jill MacLaren; McGrath, Patrick J; Finley, G Allen; Boliver, Darlene M; Mifflin, Katherine A
2013-01-01
BACKGROUND: Adverse health care events are injuries occurring as a result of patient care. Significant acute pain is often caused by medical and surgical procedures in children, and it has been argued that undermanaged pain should be considered to be an adverse event. Indicators are often used to identify other potential adverse events. There are currently no validated indicators for undertreated pediatric pain. OBJECTIVES: To develop a preliminary list of indicators of undermanaged pain in hospitalized pediatric patients. METHODS: The Delphi technique was used to survey experts in pediatric pain management and quality improvement. The first round used an electronic questionnaire to ask: “In your opinion, what indicators would signify that acute pain in a child has not been adequately controlled?” Responses were grouped together in semantically similar themes, providing a list of possible adverse event indicators. Using this list, an electronic questionnaire was developed for round 2 asking respondents to indicate the importance of each potential indicator. RESULTS: All but one indicator achieved a level of consensus ≥70%. Separate indicators emerged for postoperative and procedural pain. An additional distinction was made between indicators that could be identified by chart review and those requiring observation of practice and assessment from the child or parent. DISCUSSION: The adverse care indicators developed in the present study require further refinement. There is a need to test their clinical usability and to determine whether these indicators actually identify undermanaged pain in clinical practice. The present study is an important first step in identifying undermanaged pain in hospital and treating it as an adverse event. CONCLUSION: The adverse care indicators developed in the present study are the first step in conceptualizing mismanaged pain as an adverse event. PMID:24093121
Effects of Distant Reiki On Pain, Anxiety and Fatigue in Oncology Patients in Turkey: A Pilot Study.
Demir, Melike; Can, Gulbeyaz; Kelam, Ayhan; Aydıner, Aydın
2015-01-01
Fatigue, stress and pain are common symptoms among cancer patients, affecting the quality of life. The purpose of the present study was to determine the effect of distant Reiki on pain, anxiety and fatigue in oncology patients. Participants in the control group received usual medical and nursing care during their stay. The intervention group received usual care plus five distant Reiki sessions, one each night for 30 min. A face to face interview was performed and patient personal and illness related characteristics were evaluated using the Patient Characteristics form. Pain, stress and fatigue were evaluated according to a numeric rating scale. The experimental group was predominantly composed of women (71.4%), married individuals (40%), and primary school graduates (40%). The control group was predominantly male (72.7%), married (60%), and primary school graduates (60%). The control group demonstrated greater levels of pain (p=0.002), stress (p=0.001) and fatigue (p=0.001). The Reiki group pain score (p<0.0001), stress score (p<0.001) and fatigue score were also significantly lower. The results of this study indicate that Reiki may decreasepain, anxiety and fatigue in oncology patients.
Partyla, Tomasz; Hacker, Henriette; Edinger, Hardy; Leutzow, Bianca; Lange, Joern; Usichenko, Taras
2017-03-01
The hypoalgesic effect of electromagnetic millimeter waves (MW) is well studied in animal model; however, the results of human research are controversial. The aim of this study was to evaluate the effects of various frequency ranges of MW on hypoalgesia using the cold pressor test (CPT). Experimental pain was induced using standardized CPT protocols in 20 healthy male volunteers. The skin of the lower part of sternum was exposed to MW with a frequency of 42.25 GHz (active generator); MW within 50-75 GHz frequency range (noise generator); or an inactive MW device (placebo generator) in a random crossover double-blinded manner. Pain threshold, measured using the CPT, was the primary outcome. Other CPT parameters, heart rate, blood pressure, incidence of subjective sensations (paresthesia) during exposure, as well as quality of volunteers' blinding were also recorded. The end points of the condition with exposure to 42.25 GHz, were compared with baseline; exposure to noise 50-75 GHz; and placebo generators. Pain threshold increased during exposure to the 42.25 GHz generator when compared with baseline: median difference (MD), 1.97 seconds (95% confidence interval [CI], 0.35-3.73) and noise generator: MD, 1.27 seconds (95% CI, 0.05-2.33) but not compared with the placebo generator. Time to onset of cold and increasing pain sensations as well as diastolic blood pressure increased under the exposure to the 42.25 GHz generator when compared with baseline and noise generator. Other outcome measures were comparable among the study conditions. We were able to partially confirm the previously suggested hypoalgesic effects of low-intensity electromagnetic MW. However, the effect was indistinguishable from the placebo condition in our investigation.
Goodin, Burel R; Glover, Toni L; Sotolongo, Adriana; King, Christopher D; Sibille, Kimberly T; Herbert, Matthew S; Cruz-Almeida, Yenisel; Sanden, Shelley H; Staud, Roland; Redden, David T; Bradley, Laurence A; Fillingim, Roger B
2013-02-01
Dispositional optimism has been shown to beneficially influence various experimental and clinical pain experiences. One possibility that may account for decreased pain sensitivity among individuals who report greater dispositional optimism is less use of maladaptive coping strategies such as pain catastrophizing, a negative cognitive/affective response to pain. An association between dispositional optimism and conditioned pain modulation, a measure of endogenous pain inhibition, has previously been reported. However, it remains to be determined whether dispositional optimism is also associated with temporal summation (TS), a measure of endogenous pain facilitation. The current study examined whether pain catastrophizing mediated the association between dispositional optimism and TS among 140 older, community-dwelling adults with symptomatic knee osteoarthritis. Individuals completed measures of dispositional optimism and pain catastrophizing. TS was then assessed using a tailored heat pain stimulus on the forearm. Greater dispositional optimism was significantly related to lower levels of pain catastrophizing and TS. Bootstrapped confidence intervals revealed that less pain catastrophizing was a significant mediator of the relation between greater dispositional optimism and diminished TS. These findings support the primary role of personality characteristics such as dispositional optimism in the modulation of pain outcomes by abatement of endogenous pain facilitation and less use of catastrophizing. Results from this study further support the body of evidence that attests to the beneficial effects of positive personality traits on pain sensitivity and pain processing. Further, this study identified diminished pain catastrophizing as an important mechanism explaining the inverse relation between dispositional optimism and endogenous pain facilitation. Copyright © 2013 American Pain Society. Published by Elsevier Inc. All rights reserved.
Paungmali, Aatit; Joseph, Leonard H; Sitilertpisan, Patraporn; Pirunsan, Ubon; Uthaikhup, Sureeporn
2017-11-01
Lumbopelvic stabilization training (LPST) may provide therapeutic benefits on pain modulation in chronic nonspecific low back pain conditions. This study aimed to examine the effects of LPST on pain threshold and pain intensity in comparison with the passive automated cycling intervention and control intervention among patients with chronic nonspecific low back pain. A within-subject, repeated-measures, crossover randomized controlled design was conducted among 25 participants (7 males and 18 females) with chronic nonspecific low back pain. All the participants received 3 different types of experimental interventions, which included LPST, the passive automated cycling intervention, and the control intervention randomly, with 48 hours between the sessions. The pressure pain threshold (PPT), hot-cold pain threshold, and pain intensity were estimated before and after the interventions. Repeated-measures analysis of variance showed that LPST provided therapeutic effects as it improved the PPT beyond the placebo and control interventions (P < 0.01). The pain intensity under the LPST condition was significantly better than that under the passive automated cycling intervention and controlled intervention (P < 0.001). Heat pain threshold under the LPST condition also showed a significant trend of improvement beyond the control (P < 0.05), but no significant effects on cold pain threshold were evident. Lumbopelvic stabilization training may provide therapeutic effects by inducing pain modulation through an improvement in the pain threshold and reduction in pain intensity. LPST may be considered as part of the management programs for treatment of chronic low back pain. © 2017 World Institute of Pain.
Mathur, Vani A.; Richeson, Jennifer A.; Paice, Judith A.; Muzyka, Michael; Chiao, Joan Y.
2014-01-01
Racial disparities in pain treatment pose a significant public health and scientific problem. Prior studies demonstrate clinicians and non-clinicians are less perceptive, and suggest less treatment for, the pain of African Americans, relative to European Americans. Here we investigate the effects of explicit/implicit patient race presentation, patient race, and perceiver race on pain perception and response. African American and European American participants rated pain perception, empathy, helping motivation, and treatment suggestion in response to vignettes about patients’ pain. Vignettes were accompanied by a rapid (implicit), or static (explicit) presentation of an African or European American patient’s face. Participants perceived and responded more to European American patients in the implicit prime condition, when the effect of patient race was below the level of conscious regulation. This effect was reversed when patient race was presented explicitly. Additionally, female participants perceived and responded more to the pain of all patients, relative to male participants, and in the implicit prime condition, African American participants were more perceptive and responsive than European Americans to the pain of all patients. Taken together, these results suggest that known disparities in pain treatment may be largely due to automatic (below the level of conscious regulation), rather than deliberate (subject to conscious regulation) biases. These biases were not associated with traditional implicit measures of racial attitudes, suggesting that biases in pain perception and response may be independent of general prejudice. Perspective Results suggest racial biases in pain perception and treatment are at least partially due to automatic processes. When the relevance of patient race is made explicit, however, biases are attenuated and even reversed. We also find preliminary evidence that African Americans may be more sensitive to the pain of others than
Effects of validating communication on recall during a pain-task in healthy participants.
Carstens, Johan K P; Boersma, Katja; Schrooten, Martien G S; Linton, Steven J
2017-10-01
Increasing recall of instructions and advice in a pain consultation is important, since it is a prerequisite for adherence to treatment recommendations. However, interference due to pain-related distress may result in poor recall. Whereas there are some indications that recall can be increased by empathic communication that reduces interference, this interesting possibility remains largely untested experimentally. The current experiment aimed at studying effects of empathic communication, and more specifically validation, on recall during a pain test and possible mediators and moderators of this effect. Participants received either validating (N=25) or invalidating responses (N=25) from the experimenter during a pain provoking task, followed by self-report measures of interference (affect, situational pain catastrophizing) and recall (accurate and false memories of words). As expected, the validated group exhibited higher accurate recall and less false memories following the pain test as compared to the invalidated group. This was partly due to the effect of interference being counteracted by moderating the relationship between pain catastrophizing and recall. These novel results suggest that validating communication can counteract interference due to pain catastrophizing on recall, at least in a controlled experimental setting. Good communication by health professionals is of utmost importance for adherence to pain management. The current results expand our knowledge on the effects of pain communication by establishing and explaining a clear link between empathic communication and recall, highlighting the role of pain catastrophizing. Copyright © 2017 Scandinavian Association for the Study of Pain. Published by Elsevier B.V. All rights reserved.
Leishmania infection: painful or painless?
Borghi, Sergio M; Fattori, Victor; Conchon-Costa, Ivete; Pinge-Filho, Phileno; Pavanelli, Wander R; Verri, Waldiceu A
2017-02-01
The complex life cycle and immunopathological features underpinning the interaction of Leishmania parasites and their mammalian hosts poses frequent poorly explored and inconclusively resolved questions. The altered nociceptive signals over the course of leishmaniasis remain an intriguing issue for nociceptive and parasitology researchers. Experimental investigations have utilized behavioral, morphological, and neuro-immune approaches in the study of experimental cutaneous leishmaniasis (CL). The data generated indicates new venues for the study of the pathological characteristics of nociceptive processing in this parasitic disease. Leishmania-induced pain may be easily observed in mice and rats. However, nociceptive data is more complex in human investigations, including the occurrence of painless lesions in mucocutaneous and cutaneous leishmaniasis. Data from recent decades indicate that humans can also be affected by pain-related symptoms, often distinct from the region of body infection. The molecular and cellular mechanisms underlying such variable nociceptive states in humans during the course of leishmaniasis are an active area of research. The present article reviews nociception in leishmaniasis, including in experimental models of CL and clinical reports.
Pain experiences of patients with advanced cancer: A qualitative descriptive study.
Erol, Ozgul; Unsar, Serap; Yacan, Lale; Pelin, Meryem; Kurt, Seda; Erdogan, Bülent
2018-04-01
Uncontrolled pain, especially in patients with advanced cancer, affects quality of life negatively and causes negative physical and psychological conditions. The aim of this study was to explore the pain experiences of patients with advanced cancer and how they manage with pain, and to present a view of pain management approaches of nurses from the perspectives of the patients. This was a qualitative descriptive study of sixteen hospitalized patients with advanced cancer. Data were collected using semi-structured interviews with patients. Data were analysed by Colaizzi's phenomenological method. This study found that patients with advanced cancer who had pain experienced anxiety, helplessness, hopelessness and many restrictions in daily life as well as inability to manage with pain. Most of the patients with advanced cancer were not satisfied with their nursing care with regard to pain management. The themes that emerged were pain perception and experiences, effects of pain on daily life, pain management and management strategies and the patients' perspectives about nursing approaches to pain. This study demonstrated the difficulties of patients with advanced cancer who experienced pain in their daily lives, yet lack pain management strategies. Furthermore, nurses' caring approaches to patients with advanced cancer who experienced pain was found inadequate. Oncology nurses should provide educational interventions in order to enhance knowledge and skills about pain assessment and non-pharmacologic and pharmacologic strategies used in pain management. Copyright © 2018 Elsevier Ltd. All rights reserved.
The role of state anxiety in children's memories for pain.
Noel, Melanie; Chambers, Christine T; McGrath, Patrick J; Klein, Raymond M; Stewart, Sherry H
2012-06-01
To investigate the impact of experimentally manipulated state anxiety and the influence of anxiety-related variables on children's memories for pain. A total of 110 children (60 boys) between the ages of 8 and 12 years were randomly assigned to complete a state anxiety induction task or a control task. Following experimental manipulation, children completed a laboratory pain task, pain ratings, and questionnaire measures of anxiety-related variables. 2 weeks later, children provided pain ratings based on their memories of the pain task. The experimental manipulation effectively induced state anxiety; however, pain memories did not differ between groups. Irrespective of group assignment, children with higher state anxiety had more negative pain memories. State anxiety uniquely predicted children's pain memories over and above other well established factors. Anxiety sensitivity and trait anxiety were significant predictors of recalled pain-related fear. These data highlight the importance of anxiety in the development of children's memories for pain.
Polman, Katja; Becker, Sören L; Alirol, Emilie; Bhatta, Nisha K; Bhattarai, Narayan R; Bottieau, Emmanuel; Bratschi, Martin W; Burza, Sakib; Coulibaly, Jean T; Doumbia, Mama N; Horié, Ninon S; Jacobs, Jan; Khanal, Basudha; Landouré, Aly; Mahendradhata, Yodi; Meheus, Filip; Mertens, Pascal; Meyanti, Fransiska; Murhandarwati, Elsa H; N'Goran, Eliézer K; Peeling, Rosanna W; Ravinetto, Raffaella; Rijal, Suman; Sacko, Moussa; Saye, Rénion; Schneeberger, Pierre H H; Schurmans, Céline; Silué, Kigbafori D; Thobari, Jarir A; Traoré, Mamadou S; van Lieshout, Lisette; van Loen, Harry; Verdonck, Kristien; von Müller, Lutz; Yansouni, Cédric P; Yao, Joel A; Yao, Patrick K; Yap, Peiling; Boelaert, Marleen; Chappuis, François; Utzinger, Jürg
2015-08-18
Diarrhoea still accounts for considerable mortality and morbidity worldwide. The highest burden is concentrated in tropical areas where populations lack access to clean water, adequate sanitation and hygiene. In contrast to acute diarrhoea (<14 days), the spectrum of pathogens that may give rise to persistent diarrhoea (≥14 days) and persistent abdominal pain is poorly understood. It is conceivable that pathogens causing neglected tropical diseases play a major role, but few studies investigated this issue. Clinical management and diagnostic work-up of persistent digestive disorders in the tropics therefore remain inadequate. Hence, important aspects regarding the pathogenesis, epidemiology, clinical symptomatology and treatment options for patients presenting with persistent diarrhoea and persistent abdominal pain should be investigated in multi-centric clinical studies. This multi-country, prospective, non-experimental case-control study will assess persistent diarrhoea (≥14 days; in individuals aged ≥1 year) and persistent abdominal pain (≥14 days; in children/adolescents aged 1-18 years) in up to 2000 symptomatic patients and 2000 matched controls. Subjects from Côte d'Ivoire, Indonesia, Mali and Nepal will be clinically examined and interviewed using a detailed case report form. Additionally, each participant will provide a stool sample that will be examined using a suite of diagnostic methods (i.e., microscopic techniques, rapid diagnostic tests, stool culture and polymerase chain reaction) for the presence of bacterial and parasitic pathogens. Treatment will be offered to all infected participants and the clinical treatment response will be recorded. Data obtained will be utilised to develop patient-centred clinical algorithms that will be validated in primary health care centres in the four study countries in subsequent studies. Our research will deepen the understanding of the importance of persistent diarrhoea and related digestive disorders in
Unrod, Marina; Gironda, Ronald J; Clark, Michael E; White, Kristi E; Simmons, Vani N; Sutton, Steven K; Brandon, Thomas H
2014-08-01
The primary aim of this study was to assess smoking characteristics and cessation motivation prior to and after initiation of multidisciplinary chronic pain treatment. A secondary aim was to identify predictors of cessation motivation among smokers initiating treatment for chronic pain. We used a prospective, nonrandomized, repeated measures design. The study was conducted in a multidisciplinary specialty pain treatment program at a veterans hospital. Smokers (N = 90) referred to a multidisciplinary pain program for the treatment of chronic pain. Patients completed questionnaires assessing pain-related and smoking-related factors prior to (baseline) and 8 weeks post (follow-up) specialty pain treatment initiation. Primary outcome measures were the Contemplation Ladder and the Stages of Change (SOC) algorithm. At baseline, patients reported moderate levels of cessation motivation, and 69% were in the contemplation stage or higher on the SOC. Motivation to quit smoking was higher at follow-up compared with baseline on both continuous, t(89) = 2.11, P < 0.05, and stage-based, z = 3.69, P < 0.01, measures. At follow-up, participants reported greater interest in receiving cessation interventions, and 7.8% of patients had quit smoking. Pain-related predictors of motivation (e.g., pain intensity) were subsumed by more general predictors (e.g., nicotine dependence). Patients in this sample were more motivated to quit smoking a few weeks after, as compared with before initiating specialty pain treatment. Future research into pain-specific predictors of cessation motivation is warranted to inform the development of interventions that address pain patients' unique needs. Wiley Periodicals, Inc.
Low back pain patients' responses to videos of avoided movements.
Pincus, T; Henderson, J
2013-02-01
Fear avoidance (FA) has been identified as a risk factor for poor prognosis and a target for intervention in patients with low back pain (LBP), but the mechanisms involved need clarification. Experimental studies would benefit from the use of carefully developed and controlled stimuli representing avoided movements in back pain, and matched stimuli of movements to provide a credible control stimuli. Existing stimuli depicting avoided movements in LBP are static, do not include a set of control stimuli and do not control for possible systematic observer biases. Two studies were carried out aiming to develop and test LBP patients' responses to videos of models depicting commonly avoided movements associated with back pain, and those associated with a control condition, wrist pain. Two samples of LBP patients rated how much pain and harm each movement would cause them. They also reported how often they avoided the movement. The findings from the first study (n = 99) indicate that using videos of commonly avoided movements in low back pain is viable, and that movements associated with wrist pain provide an acceptable control stimuli. Participants in the second study (n = 85) consistently rated movements depicted by females as causing more harm, and more frequently avoided than the same movements depicted by males. The use of video stimuli could advance research into the processes associated with FA through experimental paradigms. However, although small, the model gender effects should be carefully considered. © 2012 European Federation of International Association for the Study of Pain Chapters.
Computer-Delivered Social Norm Message Increases Pain Tolerance
Pulvers, Kim; Schroeder, Jacquelyn; Limas, Eleuterio F.; Zhu, Shu-Hong
2013-01-01
Background Few experimental studies have been conducted on social determinants of pain tolerance. Purpose This study tests a brief, computer-delivered social norm message for increasing pain tolerance. Methods Healthy young adults (N=260; 44 % Caucasian; 27 % Hispanic) were randomly assigned into a 2 (social norm)×2 (challenge) cold pressor study, stratified by gender. They received standard instructions or standard instructions plus a message that contained artifically elevated information about typical performance of others. Results Those receiving a social norm message displayed significantly higher pain tolerance, F(1, 255)=26.95, p<.001, ηp2=.10 and pain threshold F(1, 244)=9.81, p=.002, ηp2=.04, but comparable pain intensity, p>.05. There were no interactions between condition and gender on any outcome variables, p>.05. Conclusions Social norms can significantly increase pain tolerance, even with a brief verbal message delivered by a video. PMID:24146086
Bouwense, Stefan A W; Olesen, Søren S; Drewes, Asbjørn M; Frøkjær, Jens B; van Goor, Harry; Wilder-Smith, Oliver H G
2013-01-01
The most dominant feature in chronic pancreatitis is intense abdominal pain. Changes in spinal and/or supraspinal central nervous system pain processing due to visceral nociceptive input play an important role in this pain. How altered pain processing is related to disease stage still needs study. Sixty chronic pancreatitis patients were compared to 15 healthy controls. Two subgroups of pancreatitis patients were defined based on the M-ANNHEIM severity index of chronic pancreatitis; i.e. moderate and severe. Pain detection and tolerance thresholds for pressure and electric stimuli were measured in six selected dermatomes (C5, T4, T10, L1, L4 and T10BACK). In addition, the conditioned pain modulation response to cold pressor task was determined. These measures were compared between the healthy controls and chronic pancreatitis patients. Severe pancreatitis patients showed lower pain thresholds than moderate pancreatitis patients or healthy volunteers. Healthy controls showed a significantly larger conditioned pain modulation response compared to all chronic pancreatitis patients taken together. The present study confirms that chronic pancreatitis patients show signs of altered central processing of nociception compared to healthy controls. The study further suggests that these changes, i.e. central sensitization, may be influenced by disease stage. These findings underline the need to take altered central pain processing into account when managing the pain of chronic pancreatitis.
Language and the pain experience.
Wilson, Dianne; Williams, Marie; Butler, David
2009-03-01
People in persistent pain have been reported to pay increased attention to specific words or descriptors of pain. The amount of attention paid to pain or cues for pain (such as pain descriptors), has been shown to be a major factor in the modulation of persistent pain. This relationship suggests the possibility that language may have a role both in understanding and managing the persistent pain experience. The aim of this paper is to describe current models of neuromatrices for pain and language, consider the role of attention in persistent pain states and highlight discrepancies, in previous studies based on the McGill Pain Questionnaire (MPQ), of the role of attention on pain descriptors. The existence of a pain neuromatrix originally proposed by Melzack (1990) has been supported by emerging technologies. Similar technologies have recently allowed identification of multiple areas of involvement for the processing of auditory input and the construction of language. As with the construction of pain, this neuromatrix for speech and language may intersect with neural systems for broader cognitive functions such as attention, memory and emotion. A systematic search was undertaken to identify experimental or review studies, which specifically investigated the role of attention on pain descriptors (as cues for pain) in persistent pain patients. A total of 99 articles were retrieved from six databases, with 66 articles meeting the inclusion criteria. After duplicated articles were eliminated, the remaining 41 articles were reviewed in order to support a link between persistent pain, pain descriptors and attention. This review revealed a diverse range of specific pain descriptors, the majority of which were derived from the MPQ. Increased attention to pain descriptors was consistently reported to be associated with emotional state as well as being a significant factor in maintaining persistent pain. However, attempts to investigate the attentional bias of specific pain
Bragatto, M M; Bevilaqua-Grossi, D; Regalo, S C H; Sousa, J D; Chaves, T C
2016-05-01
Neck pain is the most common musculoskeletal complaint among computer office workers. There are several reports about the coexistence of neck pain and temporomandibular disorders (TMD). However, there are no studies investigating this association in the context of work involving computers. The purpose of this study was to verify the association between TMD and neck pain in computer office workers. Fifty-two female computer workers who were divided into two groups: (i) those with self-reported chronic neck pain and disability (WNP) (n = 26) and (ii) those without self-reported neck pain (WONP) (n = 26), and a control group (CG) consisting of 26 women who did not work with computers participated in this study. Clinical assessments were performed to establish a diagnosis of TMD, and craniocervical mechanical pain was assessed using manual palpation and pressure pain threshold (PPT). The results of this study showed that the WNP group had a higher percentage of participants with TMD than the WONP group (42·30% vs. 23·07%, χ(2) = 5·70, P = 0·02). PPTs in all cervical sites were significantly lower in the groups WNP and WONP compared to the CG. Regression analysis revealed TMD, neck pain and work-related factors to be good predictors of disability (R(2) = 0·93, P < 0·001). These results highlighted the importance of considering the work conditions of patients with TMD, as neck disability in computer workers is explained by the association among neck pain, TMD and unfavourable workplace conditions. Consequently, this study attempted to emphasise the importance of considering work activity for minimising neck pain-related disability. © 2016 John Wiley & Sons Ltd.
Zeilig, Gabi; Rivel, Michal; Doron, Dana; Defrin, Ruth
2016-10-01
Hemiplegic shoulder pain (HSP) is a common poststroke complication and is considered to be a chronic pain syndrome. It is negatively correlated with the functional recovery of the affected arm and the quality of life of the individual. It also leads to a longer length of stay in rehabilitation. Today, there is no consensus as to the underlying mechanism causing HSP, making the syndrome difficult to treat. The aim of this study was to compare the clinical and sensory profile of individuals with HSP to that of individuals with established central neuropathic pain (CNP) in order to identify common features and the presence of neuropathic components in HSP. Cross sectional controlled study. Outpatient rehabilitation clinics. Sixteen chronic HSP patients and 18 chronic CNP patients with spinal cord injury (SCI-CNP). The chronic pain characteristics, thresholds of thermal and tactile sensations and presence of pathological sensations were compared between groups, and between painful and pain free body regions within groups. Correlations were calculated between HSP intensity and sensory and musculoskeletal characteristics. Patients with HSP and patients with SCI-CNP had similar decrease of thermal sensibility in the painful compared to intact body regions and both groups presented similar rates of pathological sensations in painful regions. HSP and SCI-CNP differed however, in the quality of pain and aggravating factors. Significant correlations were found between HSP intensity and heat-pain threshold, presence of subluxation and spasticity. The similarities between HSP and SCI-CNP and the altered spinothalamic function and sensitization suggest that HSP has neuropathic components in its mechanism. Nevertheless, the unique features of HSP point towards additional possible mechanisms. The use of specific therapy options for neuropathic pain should be considered when treating patients with HSP.
Mifflin, Katherine; Chorney, Jill; Dick, Bruce
2016-07-01
Adolescents with chronic pain often report inattention and poor memory. There has been little research on cognitive function in this population. The goal of this preliminary pilot study was to examine differences in cognitive function between adolescents with chronic pain to pain-free adolescents. All participants completed baseline assessments of pain, school absences, depression, anxiety, and sleep habits. Standardized neurocognitive tests were used to examine cognitive function with a focus on working memory and attention. Recruitment from the chronic pain clinic resulted in a female sample of 13 individuals (largely reflective of the clinical population). Pain-free age-matched and sex-matched individuals (n=12) were therefore also recruited as controls. Individuals with chronic pain had significantly lower working memory scores than controls. Differences were found between groups on the most difficult selective attention task and not on tests of sustained attention, divided attention, or attentional switching. In a stepwise regression with baseline characteristics entered in the first step, pain accounted for approximately 15% of the variance in working memory and medication score counted for 49% of the variance. This pilot study is the first study to examine differences in working memory and attention between participants with chronic pain and pain-free adolescents. Our findings suggest that chronic pain may negatively affect adolescents' working memory function and highlights the risk for cognitive difficulties and problems with educational progression in addition to negative health and social effects associated with chronic pain. The study provides a starting point for more research and has the potential to direct better identification and treatment of these cognitive deficits.
What is important in transdisciplinary pain neuroscience education? A qualitative study.
Wijma, Amarins J; Speksnijder, Caroline M; Crom-Ottens, Astrid F; Knulst-Verlaan, J M Corine; Keizer, Doeke; Nijs, Jo; van Wilgen, C Paul
2017-05-19
The main focus of Pain Neuroscience Education is around changing patients' pain perceptions and minimizing further medical care. Even though Pain Neuroscience Education has been studied extensively, the experiences of patients regarding the Pain Neuroscience Education process remain to be explored. Therefore, the aim of this study was to explore the experiences in patients with non-specific chronic pain. Fifteen patients with non-specific chronic pain from a transdisciplinary treatment centre were in-depth interviewed. Data collection and analysis were performed according to Grounded Theory. Five interacting topics emerged: (1) "the pre-Pain Neuroscience Education phase", involving the primary needs to provide Pain Neuroscience Education, with subthemes containing (a) "a broad intake" and (b) "the healthcare professionals"; (2) "a comprehensible Pain Neuroscience Education" containing (a) "understandable explanation" and (b) "interaction between the physiotherapist and psychologist"; (3) "outcomes of Pain Neuroscience Education" including (a) "awareness", b) "finding peace of mind", and (c) "fewer symptoms"; 4) "scepticism" containing (a) "doubt towards the diagnosis and Pain Neuroscience Education", (b) "disagreement with the diagnosis and Pain Neuroscience Education", and (c) "Pain Neuroscience Education can be confronting". This is the first study providing insight into the constructs contributing to the Pain Neuroscience Education experience of patients with non-specific chronic pain. The results reveal the importance of the therapeutic alliance between the patient and caregiver, taking time, listening, providing a clear explanation, and the possible outcomes when doing so. The findings from this study can be used to facilitate healthcare professionals in providing Pain Neuroscience Education to patients with non-specific chronic pain. Implications for Rehabilitation An extensive biopsychosocial patient centred intake is crucial prior to providing Pain
Increasing Optimism Protects Against Pain-Induced Impairment in Task-Shifting Performance.
Boselie, Jantine J L M; Vancleef, Linda M G; Peters, Madelon L
2017-04-01
Persistent pain can lead to difficulties in executive task performance. Three core executive functions that are often postulated are inhibition, updating, and shifting. Optimism, the tendency to expect that good things happen in the future, has been shown to protect against pain-induced performance deterioration in executive function updating. This study tested whether this protective effect of a temporary optimistic state by means of a writing and visualization exercise extended to executive function shifting. A 2 (optimism: optimism vs no optimism) × 2 (pain: pain vs no pain) mixed factorial design was conducted. Participants (N = 61) completed a shifting task once with and once without concurrent painful heat stimulation after an optimism or neutral manipulation. Results showed that shifting performance was impaired when experimental heat pain was applied during task execution, and that optimism counteracted pain-induced deterioration in task-shifting performance. Experimentally-induced heat pain impairs shifting task performance and manipulated optimism or induced optimism counteracted this pain-induced performance deterioration. Identifying psychological factors that may diminish the negative effect of persistent pain on the ability to function in daily life is imperative. Copyright © 2016 American Pain Society. Published by Elsevier Inc. All rights reserved.
Singla, Neil K; Meske, Diana S; Desjardins, Paul J
2017-12-01
In placebo-controlled acute surgical pain studies, provisions must be made for study subjects to receive adequate analgesic therapy. As such, most protocols allow study subjects to receive a pre-specified regimen of open-label analgesic drugs (rescue drugs) as needed. The selection of an appropriate rescue regimen is a critical experimental design choice. We hypothesized that a rescue regimen that is too liberal could lead to all study arms receiving similar levels of pain relief (thereby confounding experimental results), while a regimen that is too stringent could lead to a high subject dropout rate (giving rise to a preponderance of missing data). Despite the importance of rescue regimen as a study design feature, there exist no published review articles or meta-analysis focusing on the impact of rescue therapy on experimental outcomes. Therefore, when selecting a rescue regimen, researchers must rely on clinical factors (what analgesics do patients usually receive in similar surgical scenarios) and/or anecdotal evidence. In the following article, we attempt to bridge this gap by reviewing and discussing the experimental impacts of rescue therapy on a common acute surgical pain population: first metatarsal bunionectomy. The function of this analysis is to (1) create a framework for discussion and future exploration of rescue as a methodological study design feature, (2) discuss the interplay between data imputation techniques and rescue drugs, and (3) inform the readership regarding the impact of data imputation techniques on the validity of study conclusions. Our findings indicate that liberal rescue may degrade assay sensitivity, while stringent rescue may lead to unacceptably high dropout rates.
Cederbom, Sara; Rydwik, Elisabeth; Söderlund, Anne; Denison, Eva; Frändin, Kerstin; von Heideken Wågert, Petra
2014-01-01
Background To be an older woman, live alone, have chronic pain, and be dependent on support are all factors that may have an impact on daily life. One way to promote ability in everyday activities in people with pain-related conditions is to use individualized, integrated behavioral medicine in physical therapy interventions. How this kind of intervention works for older women living alone at home, with chronic pain, and dependent on formal care to manage their everyday lives has not been studied. The aim was to explore the feasibility of a study and to evaluate an individually tailored integrated behavioral medicine in physical therapy intervention for the target group of women. Materials and methods The study was a 12-week randomized trial with two-group design. Primary effect outcomes were pain-related disability and morale. Secondary effect outcomes focused on pain-related beliefs, self-efficacy for exercise, concerns of falling, physical activity, and physical performance. Results In total, 23 women agreed to participate in the study and 16 women completed the intervention. The results showed that the behavioral medicine in physical therapy intervention was feasible. No effects were seen on the primary effect outcomes. The experimental intervention seemed to improve the level of physical activity and self-efficacy for exercise. Some of the participants in both groups perceived that they could manage their everyday life in a better way after participation in the study. Conclusion Results from this study are encouraging, but the study procedure and interventions have to be refined and tested in a larger feasibility study to be able to evaluate the effects of these kinds of interventions on pain-related disability, pain-related beliefs, self-efficacy in everyday activities, and morale in the target group. Further research is also needed to refine and evaluate effects from individualized reminder routines, support to collect self-report data, safety procedures for
Siegenthaler, Andreas; Bütikofer, Lukas; Limacher, Andreas; Juni, Peter; Vuilleumier, Pascal H.; Stamer, Ulrike; Arendt-Nielsen, Lars; Curatolo, Michele
2018-01-01
Antidepressants are frequently prescribed as co-analgesics in chronic pain. While their efficacy is well documented for neuropathic pain, the evidence is less clear in musculoskeletal pain conditions. The present study therefore evaluated the effect of the tricyclic antidepressant imipramine on chronic low-back pain in a randomized, double-blinded placebo-controlled design. To explore the mechanisms of action and the influence of drug metabolism, multimodal quantitative sensory tests (QST) and genotyping for cytochrome P450 2D6 (CYP2D6) were additionally performed. A single oral dose of imipramine 75 mg was compared to active placebo (tolterodine 1 mg) in 50 patients (32 females) with chronic non-specific low-back pain. Intensity of low-back pain was assessed on a 0–10 numeric rating scale at baseline and every 30 minutes after drug intake. Multimodal QST were performed at baseline and in hourly intervals for 2 hours. Pharmacogenetic influences of cytochrome P450 were addressed by CYP2D6 genotyping. No significant analgesic effect was detected neither on low-back pain nor on any of the sensory tests in the overall analyses. However, evidence for an interaction of the imipramine effect and CYP2D6 genotype was found for electrical and for pressure pain detection thresholds. Intermediate but not extensive metabolizers had a 1.20 times greater electrical pain threshold (95%-CI 1.10 to 1.31) and a 1.10 times greater pressure pain threshold (95%-CI 1.01 to 1.21) 60 minutes after imipramine than after placebo (p<0.001 and p = 0.034, respectively). The present study failed to demonstrate an immediate analgesic effect of imipramine on low-back pain. Anti-nociceptive effects as assessed by quantitative sensory tests may depend on CYP2D6 genotype, indicating that metabolizer status should be accounted for when future studies with tricyclic antidepressants are undertaken. PMID:29742109
The “at-home LLLT” in temporo-mandibular disorders pain control: a pilot study
Pelosi, A; Queirolo, V; Vescovi, P; Merigo, E
2015-01-01
Objectives: The Temporo-Mandibular Disorders (TMD) are a set of dysfunctional patterns concerning the temporo-mandibular joints (TMJ) and the masticatory muscles; its main symptom is pain, probably caused by inflammatory changes in the synovial membrane, alterations in the bone marrow of the mandibular condyle and impingement and compression. The aim of this preliminary study was to investigate the effectiveness in the TMD pain reduction of a new laser device recently proposed by the commerce that, due to its reduced dimensions and to be a class I laser according the ANSI classification, may be used at home by the patient himself. Material and methods: Twenty-four patients with TMD were randomly selected: the inclusion criteria for the sample was the diagnosis of mono- or bi-lateral TMD, with acute pain restricted to the joint area, associated with the absence of any muscle tenderness during palpation. The patients were randomly assigned to two groups: Group 1 (12 patients): patients receiving real LLLT (experimental group). Group 2 (12 patients): patients receiving inactive laser (placebo group). The treatment was performed once a day for two weeks with an 808 nm diode laser by the patient himself with irradiation of the cutaneous zone corresponding to the TMJ for 15 minutes each side. Each patient was instructed to express its pain in a visual analogue scale (VAS) making a perpendicular line between the two extremes representing the felt pain level. Statistical analysis was realized with GraphPad Instat Software, where P<0.05 was considered significant and P<0.01 very significant. Results: The patient's pain evaluation was expressed in the two study groups before the treatment, 1 week and two weeks after the treatment. The differences between the two groups result extremely significant with p<0.0001 for the comparison of VAS value after 1 and 2 weeks. Conclusion: This study, even if it may be considered such a pilot study, investigated a new way to control the
Vervoort, Tine; Trost, Zina; Sütterlin, Stefan; Caes, Line; Moors, Agnes
2014-08-01
We investigated the function of parental attention to child pain in regulating parental distress and pain control behaviour when observing their child performing a painful (cold pressor) task (CPT); we also studied the moderating role of parental state anxiety. Participants were 62 schoolchildren and one of their parents. Parental attention towards or away from child pain (ie, attend to pain vs avoid pain) was experimentally manipulated during a viewing task pairing unfamiliar children's neutral and pain faces. Before and after the viewing task, parental distress regulation was assessed by heart rate (HR) and heart rate variability (HRV). In a subsequent phase, parents observed their own child perform a CPT task, allowing assessment of parental pain control behaviour (indexed by latency to stop their child's CPT performance) and parental distress, which was assessed via self-report before and after observation of child CPT performance. Eye tracking during the viewing task and self-reported attention to own child's pain confirmed successful attention manipulation. Further, findings indicated that the effect of attentional strategy on parental emotion regulation (indexed by HR, self-report) and pain control behaviour depended on parents' state anxiety. Specifically, whereas low anxious parents reported more distress and demonstrated more pain control behaviour in the Attend to Pain condition, high anxious parents reported more distress and showed more pain control behaviour in the Avoid Pain condition. This inverse pattern was likewise apparent in physiological distress indices (HR) in response to the initial viewing task. Theoretical/clinical implications and further research directions are discussed. Copyright © 2014 International Association for the Study of Pain. Published by Elsevier B.V. All rights reserved.
Mahigir, Foroogh; Khanehkeshi, Ali; Karimi, Ayatollah
2012-01-01
The aim of the present study is to find out the influence of rational-emotive behavior therapy (REBT) on pain intensity among cancer patients in India and Iran. The study followed a quasi-experimental, pre-post test, carried out with a sample of 88 cancer patients, aged 21-52 years, referred to the Baharat cancer hospital of Mysore in India and Shahidzade hospital of Behbahan in Iran. They were randomly assigned to the experimental (n=India 21; Iran 22) and control (n=India 22; Iran 23) groups. Pain was measured with the McGill Pain Questionnaire- MPQ (1975), the intervention by REBT has given to the experimental group for 45 days (ten sessions) and at the end of intervention, the pain of patients was again evaluated. Concerning to hypothesis of the study, two independent sample T test and three ways mixed ANOVA is used to analyze the data. Results showed that the experimental group in post test had less pain than the control group, but there were no statistically significant differences between Indian and Iranian patients in pain perception. With respect the outcome of study, it has realized that REBT can be used in hospitals and other psychological clinics to reduce the pain of cancer patients.
Study protocol title: a prospective cohort study of low back pain.
Garg, Arun; Hegmann, Kurt T; Moore, J Steven; Kapellusch, Jay; Thiese, Matthew S; Boda, Sruthi; Bhoyr, Parag; Bloswick, Donald; Merryweather, Andrew; Sesek, Richard; Deckow-Schaefer, Gwen; Foster, James; Wood, Eric; Sheng, Xiaoming; Holubkov, Richard
2013-03-07
Few prospective cohort studies of workplace low back pain (LBP) with quantified job physical exposure have been performed. There are few prospective epidemiological studies for LBP occupational risk factors and reported data generally have few adjustments for many personal and psychosocial factors. A multi-center prospective cohort study has been incepted to quantify risk factors for LBP and potentially develop improved methods for designing and analyzing jobs. Due to the subjectivity of LBP, six measures of LBP are captured: 1) any LBP, 2) LBP ≥ 5/10 pain rating, 3) LBP with medication use, 4) LBP with healthcare provider visits, 5) LBP necessitating modified work duties and 6) LBP with lost work time. Workers have thus far been enrolled from 30 different employment settings in 4 diverse US states and performed widely varying work. At baseline, workers undergo laptop-administered questionnaires, structured interviews, and two standardized physical examinations to ascertain demographics, medical history, psychosocial factors, hobbies and physical activities, and current musculoskeletal disorders. All workers' jobs are individually measured for physical factors and are videotaped. Workers are followed monthly for the development of low back pain. Changes in jobs necessitate re-measure and re-videotaping of job physical factors. The lifetime cumulative incidence of low back pain will also include those with a past history of low back pain. Incident cases will exclude prevalent cases at baseline. Statistical methods planned include survival analyses and logistic regression. Data analysis of a prospective cohort study of low back pain is underway and has successfully enrolled over 800 workers to date.
Beyaz, Serbülent Gökhan; Ergönenç, Jalan Şerbetçigil; Ergönenç, Tolga; Sönmez, Özlem Uysal; Erkorkmaz, Ünal; Altintoprak, Fatih
2016-01-05
Postmastectomy pain syndrome (PMPS) is defined as a chronic (continuing for 3 or more months) neuropathic pain affecting the axilla, medial arm, breast, and chest wall after breast cancer surgery. The prevalence of PMPS has been reported to range from 20% to 68%. In this study, we aimed to determine the prevalence of PMPS among mastectomy patients, the severity of neuropathic pain in these patients, risk factors that contribute to pain becoming chronic, and the effect of PMPS on life quality. This cross-sectional study was approved by the Sakarya University, Medical Faculty Ethical Council and included 146 patients ranging in age from 18 to 85 years who visited the pain clinic, general surgery clinic, and oncology clinic and had breast surgery between 2012 and 2014. Patients were divided into two groups according to whether they met PMPS criteria: pain at axilla, arm, shoulder, chest wall, scar tissue, or breast at least 3 months after breast surgery. All patients gave informed consent prior to entry into the study. Patient medical records were collected, and pain and quality of life were evaluated by the visual analog scale (VAS) for pain, a short form of the McGill Pain Questionnaire (SF-MPQ), douleur neuropathique-4 (DN-4), and SF-36. Patient mean age was 55.2 ± 11.8 years (33.0-83.0 years). PMPS prevalence was 36%. Mean scores on the VAS, SF-MPQ, and DN-4 in PMPS patients were 1.76 ± 2.38 (0-10), 1.73 ± 1.54 (0-5), and 1.64 ± 2.31 (0-8), respectively. Of these patients, 31 (23.7%) had neuropathic pain characteristics, and 12 (9.2%) had phantom pain according to the DN-4 survey. Patients who had modified radical mastectomy were significantly more likely to develop PMPS than patients who had breast-protective surgery (P = 0.028). Only 2 (2.4%) of PMPS patients had received proper treatment (anticonvulsants or opioids). PMPS seriously impacts patients' emotional situation, daily activities, and social relationships and is a major economic burden for health
Hypnotherapy of a pain disorder: a clinical case study.
Artimon, Henrieta Mihaela
2015-01-01
Hypnotherapy's effectiveness in improving and controlling chronic pain of various etiologies has been demonstrated by studies; the mechanism by which hypnosis does this is more complex than a simple induction of muscle relaxation. This study reveals, in addition to this mechanism, a deeper dimension of hypnotherapy from the vantage of a patient with a medical-surgical background, diagnosed with a pain disorder and major severe depressive disorder in addition to incurable painful symptoms, through treatment associated with hypnoanalysis. Following psychotherapy, which included some elements of cognitive-behavioral therapy, a complete remission of the anxious-depressive mood and the painful symptoms was achieved.
Henchoz, Yves; Tétreau, Charles; Abboud, Jacques; Piché, Mathieu; Descarreaux, Martin
2013-10-01
Alterations of the neuromuscular control of the lumbar spine have been reported in patients with chronic low back pain (LBP). During trunk flexion and extension tasks, the reduced myoelectric activity of the low back extensor musculature observed during full trunk flexion is typically absent in patients with chronic LBP. To determine whether pain expectations could modulate neuromuscular responses to experimental LBP to a higher extent in patients with chronic LBP compared with controls. A cross-sectional, case-control study. Twenty-two patients with nonspecific chronic LBP and 22 age- and sex-matched control participants. Trunk flexion-extension tasks were performed under three experimental conditions: innocuous heat, noxious stimulation with low pain expectation, and noxious stimulation with high pain expectation. Noxious stimulations were delivered using a contact heat thermode applied on the skin of the lumbar region (L4-L5), whereas low or high pain expectations were induced by verbal and visual instructions. Surface electromyography of erector spinae at L2-L3 and L4-L5, as well as lumbopelvic kinematic variables were collected during the tasks. Pain was evaluated using a numerical rating scale. Pain catastrophizing, disability, anxiety, and fear-avoidance beliefs were measured using validated questionnaires. Two-way mixed analysis of variance revealed that pain was significantly different among the three experimental conditions (F2,84=317.5; p<.001). Increased myoelectric activity of the low back extensor musculature during full trunk flexion was observed in the high compared with low pain expectations condition at the L2-L3 level (F2,84=9.5; p<.001) and at the L4-L5 level (F2,84=3.7; p=.030). At the L4-L5 level, this effect was significantly more pronounced for the control participants compared with patients with chronic LBP (F2,84=3.4; p=.045). Pearson correlation analysis revealed that increased lumbar muscle activity in full flexion induced by
Hemington, Kasey S; Cheng, Joshua C; Bosma, Rachael L; Rogachov, Anton; Kim, Junseok A; Davis, Karen D
2017-09-01
Resilience, a characteristic that enhances adaptation in response to stressful events, is a positive psychological factor that can predict and modulate health outcomes. However, resilience is rarely considered in pain research. Conversely, negative psychological factors (eg, anxiety, depression) are known to be related to the affective dimension of pain. It is critical to understand all potential psychological drivers of pain affect, a prominent component of chronic pain. We tested the hypothesis that higher resilience is associated with lower pain affect, above and beyond the predictive value of negative psychological factors. Healthy adults underwent psychophysical testing to acquire ratings of heat pain intensity and unpleasantness and completed the Resilience Scale, the State-Trait Anxiety Inventory (trait form), Beck Depression Inventory, Pain Catastrophizing Scale, and the Pain Vigilance and Attention Questionnaire. Multiple regression modeling (n = 68) showed resilience to be a negatively associated with pain affect (unpleasantness). Furthermore, in individuals with higher anxiety scores, resilience was protective against higher pain affect. This highlights the importance of resilience, a positive psychological factor, in the affective dimension of pain. This study is the first to assess a positive psychological factor and experimental pain affect, and has the potential to improve prediction of and treatment strategies for clinical pain. We report that resilience, a positive psychological factor, interacts with anxiety and is associated with heat pain affect (unpleasantness) in healthy individuals. Resilience may provide predictive value of chronic pain affect and treatment outcomes, and could be a target for behavioral therapy. Copyright © 2017 American Pain Society. Published by Elsevier Inc. All rights reserved.
Long, Blaine C; Knight, Kenneth L; Hopkins, Ty; Parcell, Allen C; Feland, J Brent
2012-08-01
It is suggested that postinjury pain is difficult to examine; thus, investigators have developed experimental pain models. To minimize pain, cryotherapy (cryo) is applied, but reports on its effectiveness are limited. To investigate a pain model for the anterior knee and examine cryo in reducing the pain. Controlled laboratory study. Therapeutic modality laboratory. 30 physically active healthy male subjects who were free from any lower extremity orthopedic, neurological, cardiovascular, or endocrine pathologies. Perceived pain was measured every minute. Surface temperature was also assessed in the center of the patella and the popliteal fossa. There was a significant interaction between group and time (F68,864 = 3.0, P = .0001). At the first minute, there was no difference in pain between the 3 groups (saline/cryo = 4.80 ± 4.87 mm, saline/sham = 2.80 ± 3.55 mm, no saline/cryo = 4.00 ± 3.33 mm). During the first 5 min, pain increased from 4.80 ± 4.87 to 45.90 ± 21.17 mm in the saline/cryo group and from 2.80 ± 3.55 to 31.10 ± 20.25 mm in the saline/sham group. Pain did not change within the no-saline/cryo group, 4.00 ± 3.33 to 1.70 ± 1.70 mm. Pain for the saline/sham group remained constant for 17 min. Cryo decreased pain for 16 min in the saline/cryo group. There was no difference in preapplication surface temperature between or within each group. No change in temperature occurred within the saline/sham. Cooling and rewarming were similar in both cryo groups. Ambient temperature fluctuated less than 1°C during data collection. Intermittent infusion of sterile 5% hypertonic saline may be a useful experimental pain model in establishing a constant level of pain in a controlled laboratory setting. Cryotherapy decreased the induced anterior knee pain for 16 min.
Management of Myofascial Pain of Upper Trapezius: A Three Group Comparison Study
Kannan, Priya
2012-01-01
It is important to identify the most effective therapeutic modality in the management of myofascial trigger points (MTPt). Thus we aimed to study the effect of therapeutic ultrasound, laser and ischemic compression in reducing pain and improving cervical range of motion among patients with MTPt. Experimental study comparing three groups was designed as a 5 days trial, a co-relational design was considered. Outcome measures: VAS for pain, provocative pain test using “soft tissue tenderness grading scheme” and active cervical lateral flexion using inch tape. Methods- Patients were divided into 3 groups, Gr 1 underwent treatment using therapeutic ultrasound, Gr 2 with therapeutic laserand Gr 3 with ischemic compression. Assessments were done on day 1 and day 5 of treatment respectively. Results: ANOVA revealed improvement among all 3 groups as statistically significant difference (p<0.05) between the start and end of trial. Analysis using Chi square test shows a statistically significant difference in the improvement between laser and the other 2 groups. Mean difference in the change of scores between the assessments showed laser therapy to have a tendency towards progressive improvement over the treatment period and a better improvement than the other 2 groups. Weconclude that laser can be used as an effective treatment regimen in the management of myofascial trigger points thereby reducing disability caused due to musculoskeletal pathology. PMID:22980377
Coping With Pain: Studies in Stress Inoculation.
ERIC Educational Resources Information Center
Horan, John J.; And Others
The stress-inoculation paradigm for helping clients deal with pain consists of education about the psychological dimensions of pain, training in a number of coping skills relevant to each dimension, and practice in applying these skills to the noxious stimulus. Presented are two studies, the first of which represents a component analysis of stress…
de Jong, Jeroen R; Vlaeyen, Johan W S; van Eijsden, Marjon; Loo, Christoph; Onghena, Patrick
2012-10-01
There is increasing evidence that pain-related fear influences the development and maintenance of pain disability, presumably mediated through the fear-related avoidance of valued activities. Individually tailored graded exposure in vivo (GEXP) has been demonstrated to reduce pain-related fear and increase functional abilities in patients with chronic low back pain, neck pain, and complex regional pain syndrome. The current study aimed to test whether these effects generalize towards patients with work-related upper extremity pain. A sequential replicated and randomized single-case experimental phase design with multiple measurements was used. Within each participant, GEXP was compared to a no-treatment baseline period and a no-treatment 6-month follow-up period. Eight patients who reported a high level of pain-related fear were included in the study. Daily changes in pain catastrophizing, pain-related fear, and pain intensity were assessed using a diary, and subjected to randomization tests. Before the start of the baseline period, just after GEXP, and at 6-month follow-up, clinically relevant changes of pain catastrophizing, pain-related fear, perceived harmfulness of physical activity, pain disability, and participation/autonomy were verified. When GEXP was introduced, levels of pain catastrophizing and pain-related fear decreased significantly. Clinically relevant improvements were observed for pain disability, perceived participation, and autonomy. These favourable changes were maintained until 6-month follow-up. The findings of the current study underscore the external validity of a cognitive-behavioural GEXP treatment for patients with chronic pain reporting increased pain-related fear. Copyright © 2012 International Association for the Study of Pain. Published by Elsevier B.V. All rights reserved.
He, Hong-Gu; Jahja, Riawati; Sinnappan, Rajammal; Ang, Emily Neo Kim; Lee, Tat-Leang; Chan, Moon Fai; Vehviläinen-Julkunen, Katri
2011-09-01
This study examined the impact of an educational intervention (booklet distribution and lectures) on Singaporean nurses' provision of guidance to parents on the use of non-pharmacological methods of pain relief for their child's postoperative pain. Using a quasi-experimental one-group pre- and post-test study design, 134 and 112 registered nurses completed the questionnaires pre- and post-test, respectively. More than 75% of the nurses "always" guided parents to use breathing techniques, relaxation, positioning, comforting/reassurance, helping with activities of daily living, and creating a comfortable environment in the pretest and touch, presence, and distraction in addition to the aforementioned methods in the post-test. The nurses' provision of guidance to parents on all non-pharmacological methods increased, but statistically significant increases only were found in relation to massage and positive reinforcement. The results suggested that the educational intervention had some impact on nurses' provision of guidance to parents on the use of non-pharmacological methods of pain relief for children's postoperative pain. Continuing education in pain management should be provided to nurses in order to equip them with the knowledge to improve their practice. © 2011 Blackwell Publishing Asia Pty Ltd.
Postoperative pain management experiences among school-aged children: a qualitative study.
Sng, Qian Wen; Taylor, Beverley; Liam, Joanne Lw; Klainin-Yobas, Piyanee; Wang, Wenru; He, Hong-Gu
2013-04-01
To explore postoperative pain management experiences among school-aged children. Ineffective postoperative pain management among children has been commonly reported. School-aged children are able to evaluate how their pain is managed and what their preferred strategies are. Most studies in pain management have adopted quantitative methods and have overlooked children's pain management experiences. This is a qualitative study using face-to-face interviews. Data were collected from 15 school-aged children admitted to a tertiary hospital in Singapore by in-depth interviews conducted between November 2010 and January 2011. Data were analysed by thematic analysis. Five themes were identified: children's self-directed actions to relieve their postoperative pain (e.g. using cognitive-behavioural methods of distraction and imagery, physical method of positioning, sleeping and drinking, seeking other people's help by informing parents and crying and using pain medications); children's perceptions of actions parents take for their postoperative pain relief (assessing pain, administering pain medications, using various cognitive-behavioural, physical methods and emotional support strategies, assisting in activities and alerting health professionals); children's perception of actions nurses take for their postoperative pain relief (administering medication, using cognitive-behavioural methods, emotional support strategies and helping with activities of daily living) and suggestions for parents (using distraction and presence) and nurses (administering medications, distraction and positioning) for their postoperative pain relief improvement. This study contributed to the existing knowledge about children's postoperative pain management based on their own experiences. Children, their parents and nurses used various strategies, including pain medication and non-pharmacological methods, especially distraction, for children's postoperative pain relief. This study provides evidence
Thoracic costotransverse joint pain patterns: a study in normal volunteers.
Young, Brian A; Gill, Howard E; Wainner, Robert S; Flynn, Timothy W
2008-10-15
Pain referral patterns of asymptomatic costotransverse joints have not been established. The objective of this study was to determine the pain referral patterns of asymptomatic costotransverse joints via provocative intra-articular injection. Eight asymptomatic male volunteers received a combined total of 21 intra-articular costotransverse joint injections. Fluoroscopic imaging was used to identify and isolate each costotransverse joint and guide placement of a 25 gauge, 2.5 inch spinal needle into the costotransverse joint. Following contrast medium injection, the quality, intensity, and distribution of the resultant pain produced were recorded. Of the 21 costotransverse joint injections, 16 (76%) were classified as being intra-articular via arthrograms taken at the time of injection, and 14 of these injections produced a pain sensation distinctly different from that of needle placement. Average pain produced was 3.3/10 on a 0-10 verbal pain scale. Pain was described generally as a deep, dull ache, and pressure sensation. Pain patterns were located superficial to the injected joint, with only the right T2 injections showing referred pain 2 segments cranially and caudally. No chest wall, upper extremity or pseudovisceral pains were reported. This study provides preliminary data of the pain referral patterns of costotransverse joints. Further research is needed to compare these findings with those elicited from symptomatic subjects.
Perinatal maternal stress and serotonin signaling: effects on pain sensitivity in offspring.
Knaepen, Liesbeth; Pawluski, Jodi L; Patijn, Jacob; van Kleef, Maarten; Tibboel, Dick; Joosten, Elbert A
2014-07-01
It has been estimated that 20% of pregnant women are facing perinatal stress and depression. Perinatal maternal stress has been shown to increase pain sensitivity in offspring. For the treatment of their depressive symptoms, pregnant women are frequently prescribed selective serotonin reuptake inhibitors (SSRIs). Since the descending pain inhibitory circuit matures perinatally, perinatal SSRI exposure has been shown to affect pain sensitivity in offspring. In the present review, we summarize experimental and clinical evidence for the effect of perinatal maternal stress and SSRI exposure on pain sensitivity in offspring. Both experimental and clinical studies show the effect of perinatal maternal stress on regulation of the hypothalamic-pituitary-adrenal (HPA) system and the serotonin pain inhibitory system. Alterations in these two systems likely underlie long-term alterations in the development of pain sensitivity. This review sheds light on the effect of perinatal maternal stress and treatment with SSRIs on offspring pain sensitivity, in relation to the developing HPA system and 5-HT signaling. © 2013 Wiley Periodicals, Inc.
Surgical animal models of neuropathic pain: Pros and Cons.
Challa, Siva Reddy
2015-03-01
One of the biggest challenges for discovering more efficacious drugs for the control of neuropathic pain has been the diversity of chronic pain states in humans. It is now acceptable that different mechanisms contribute to normal physiologic pain, pain arising from tissue damage and pain arising from injury to the nervous system. To study pain transmission, spot novel pain targets and characterize the potential analgesic profile of new chemical entities, numerous experimental animal pain models have been developed that attempt to simulate the many human pain conditions. Among the neuropathic pain models, surgical models have paramount importance in the induction of pain states. Many surgical animal models exist, like the chronic constriction injury (CCI) to the sciatic nerve, partial sciatic nerve ligation (pSNL), spinal nerve ligation (SNL), spared nerve injury (SNI), brachial plexus avulsion (BPA), sciatic nerve transaction (SNT) and sciatic nerve trisection. Most of these models induce responses similar to those found in causalgia, a syndrome of sustained burning pain often seen in the distal extremity after partial peripheral nerve injury in humans. Researchers most commonly use these surgical models in both rats and mice during drug discovery to screen new chemical entities for efficacy in the area of neuropathic pain. However, there is scant literature that provides a comparative discussion of all these surgical models. Each surgical model has its own benefits and limitations. It is very difficult for a researcher to choose a suitable surgical animal model to suit their experimental set-up. Therefore, particular attention has been given in this review to comparatively provide the pros and cons of each model of surgically induced neuropathic pain.
Goodin, Burel; Kindler, Lindsay L.; Caudle, Robert M.; Edwards, Robert R.; Gravenstein, Nikolaus; Riley, Joseph L.; Fillingim, Roger B.
2013-01-01
The current study tested the hypothesis that conditioned pain modulation is mediated by the release of endogenous opioids with a placebo-controlled (sugar pill) study of naltrexone (50 mg) in 33 healthy volunteers over two counter-balanced sessions. Pain modulation consisted of rating of heat pain (palm) during concurrent cold water immersion (foot). Compared to baseline heat pain ratings, concurrent foot immersion lowered pain intensity ratings, which suggests an inhibitory effect, was reduced with naltrexone, suggesting at least partial dependence of inhibition on endogenous opioids. An exploratory analysis revealed that individual differences in catastrophizing moderated the effects of naltrexone; endogenous opioid blockade abolished modulation in subjects lower in catastrophizing while modulation was unaffected by naltrexone among high catastrophizers. The results suggest a role of endogenous opioids in endogenous analgesia, but hint that multiple systems might contribute to conditioned pain modulation, and that these systems might be differentially activated as a function of individual differences in responses to pain. PMID:22534819
Geber, Christian; Fondel, Ricarda; Krämer, Heidrun H; Rolke, Roman; Treede, Rolfe-Detlef; Sommer, Claudia; Birklein, Frank
2007-06-01
Intradermal capsaicin injection (CAP) and electrical current stimulation (ES) are analyzed in respect to patterns and test-retest reliability of pain as well as sensory and neurosecretory changes. In 10 healthy subjects, 2x CAP (50 microg) and 2x ES (5 to 30 mA) were applied to the volar forearm. The time period between 2 identical stimulations was about 4 months. Pain ratings, areas of mechanical hyperalgesia, and allodynia were assessed. The intensity of sensory changes was quantified by using quantitative sensory testing. Neurogenic flare was assessed by using laser Doppler imaging. Calcitonin gene-related peptide (CGRP) release was quantified by dermal microdialysis in combination with an enzyme immunoassay. Time course and peak pain ratings were different between CAP and ES. Test-retest correlation was high (r > or = 0.73). Both models induced primary heat hyperalgesia and primary plus secondary pin-prick hyperalgesia. Allodynia occurred in about half of the subjects. Maximum flare sizes did not differ between CAP and ES, but flare intensities were higher for ES. Test-retest correlation was higher for flare sizes than for flare intensity. A significant CGRP release could only be measured after CAP. The different time courses of pain stimulation (CAP: rapidly decaying pain versus ES: pain plateau) led to different peripheral neurosecretory effects but induced similar central plasticity and hyperalgesia. The present study gives a detailed overview of psychophysical and neurosecretory characteristics induced by noxious stimulation with capsaicin and electrical current. We describe differences, similarities, and reproducibility of these human pain models. These data might help to interpret past and future results of human pain studies using experimental pain.
Chng, Hui Yi; He, Hong-Gu; Chan, Sally Wai-Chi; Liam, Joanne Li Wee; Zhu, Lixia; Cheng, Karis Kin Fong
2015-06-01
To examine parents' knowledge about and attitudes towards pain management, use of pain relief strategies and satisfaction with their children's postoperative pain management, as well as the relationships among these variables. Children's postoperative pain is inadequately managed worldwide. Despite increasing emphasis on parental involvement in children's postoperative pain management, few studies have examined parents' management of their child's postoperative pain in Singapore. A descriptive correlational study. A convenience sample of 60 parents having 6- to 14-year-old children undergoing inpatient elective surgery in a public hospital in Singapore was recruited. Data were collected one day after each child's surgery using the Pain Management Knowledge and Attitudes questionnaire and the Parents' Use of Pain Relief Strategies questionnaire. Descriptive statistics, Mann-Whitney U tests, Kruskal-Wallis tests and Spearman's rank correlation coefficient were used for data analyses. Parents displayed moderate levels of knowledge, attitudes and use of pain relief methods in relation to their children's postoperative pain and pain management. They were generally satisfied with the management of their child's postoperative pain. There was significant difference in Parents' Use of Pain Relief Strategies scores between parents with and without previous experience of caring for their hospitalised child. Statistically significant positive correlations were found between parents' knowledge and attitude, knowledge and satisfaction, attitude and satisfaction, knowledge and pain relief strategies, as well as attitude and pain relief strategies. This study indicates the need to provide parents with more information regarding their children's postoperative pain management. Future studies are needed to develop educational interventions for parents to improve their knowledge and attitudes, which will eventually improve their use of pain relief strategies for their children. Health
Cognitive load selectively influences the interruptive effect of pain on attention.
Moore, David J; Eccleston, Christopher; Keogh, Edmund
2017-10-01
Pain is known to interrupt attentional performance. Such interference effects seem to occur preferentially for tasks that are complex and/or difficult. However, few studies have directly manipulated memory load in the context of pain interference to test this view. Therefore, this study examines the effect of experimental manipulations of both memory load and pain on 3 tasks previously found to be sensitive to pain interference. Three experiments were conducted. A different task was examined in each experiment, each comprising of a high- and low-cognitive load versions of the task. Experiment 1 comprised an attention span (n-back) task, experiment 2 an attention switching task, and experiment 3 a divided attention task. Each task was conducted under painful and nonpainful conditions. Within the pain condition, an experimental thermal pain induction protocol was administered at the same time participants completed the task. The load manipulations were successful in all experiments. Pain-related interference occurred under the high-load condition but only for the attention span task. No effect of pain was found on either the attentional switching or divided attention task. These results suggest that while cognitive load may influence the interruptive effect of pain on attention, this effect may be selective. Because pain affected the high-load version of the n-back task but did not interrupt performance on attentional switching or dual-task paradigms, this means that our findings did not completely support our hypotheses. Future research should explore further the parameters and conditions under which pain-related interference occurs.
Older Age as a Prognostic Factor of Attenuated Pain Recovery after Shoulder Arthroscopy
Simon, Corey B.; Riley, Joseph L.; Coronado, Rogelio A.; Valencia, Carolina; Wright, Thomas W.; Moser, Michael W.; Farmer, Kevin W.; George, Steven Z.
2015-01-01
Background Shoulder pain and surgery are common among older adults. However, the extent to which older age affects recovery after shoulder surgery is not well understood. Objective To assess influence of older age on post-operative recovery factors three and six months after shoulder arthroscopy. Design Prospective Cohort Study Setting Institutional Patients Convenience sample of 139 individuals between 20 and 79 years of age who experienced shoulder pain, musculoskeletal dysfunction based on imaging and physician assessment, and were scheduled for an arthroscopic shoulder procedure. Main Outcome Measures Post-operative outcomes were compared among younger, middle-aged and older adults at pre-surgery, 3 months and 6 months after surgery using ANOVA modeling. Movement-evoked pain and an experimental laboratory correlate of pain processing were assessed at each time point. Older age influence on three and six month pain outcomes were determined via multivariate regression analyses after accounting for pre-operative, intra-operative, and post-operative prognostic factors. Results Older adults had higher movement-evoked pain intensity (F2,108 = 5.18, p=.007) and experimental pain response (F2,111 = 7.24, p=.001) at three months compared to young and middle-aged adults. After controlling for key prognostic factors, older age remained a positive predictor of three-month movement-evoked pain (R2=.05; St. Beta=.263, p=.031) and experimental pain response (R2=.07; St. Beta=.295, p=.014). Further, older age remained a positive predictor of movement-evoked pain at six months (R2=.04; St. Beta=.231, p=.004), despite no age group differences in outcome. Older age was found to be the strongest predictor of three and six month movement-evoked pain. Conclusion Older adults may experience more pain related to movement as well as endogenous pain excitation in the first few months after shoulder arthroscopy. Future age-related research should consider use of movement-evoked pain
Bromley Milton, Maria; Börsbo, Björn; Rovner, Graciela; Lundgren-Nilsson, Åsa; Stibrant-Sunnerhagen, Katharina; Gerdle, Björn
2013-01-01
Background Incorporating the patient's view on care and treatment has become increasingly important for health care. Patients describe the variety of consequences of their chronic pain conditions as significant pain intensity, depression, and anxiety. We hypothesised that intensities of common symptoms in chronic pain conditions carry important information that can be used to identify clinically relevant subgroups. This study has three aims: 1) to determine the importance of different symptoms with respect to participation and ill-health; 2) to identify subgroups based on data concerning important symptoms; and 3) to determine the secondary consequences for the identified subgroups with respect to participation and health factors. Methods and Subjects This study is based on a cohort of patients referred to a multidisciplinary pain centre at a university hospital (n = 4645, participation rate 88%) in Sweden. The patients answered a number of questionnaires concerning symptoms, participation, and health aspects as a part of the Swedish Quality Registry for Pain Rehabilitation (SQRP). Results Common symptoms (such as pain intensity, depression, and anxiety) in patients with chronic pain showed great variability across subjects and 60% of the cohort had normal values with respect to depressive and anxiety symptoms. Pain intensity more than psychological symptoms showed stronger relationships with participation and health. It was possible to identify subgroups based on pain intensity, depression, and anxiety. With respect to participation and health, high depressive symptomatology had greater negative consequences than high anxiety. Conclusions Common symptoms (such as pain intensity and depressive and anxiety symptoms) in chronic pain conditions carry important information that can be used to identify clinically relevant subgroups. PMID:23805183
Study protocol title: a prospective cohort study of low back pain
2013-01-01
Background Few prospective cohort studies of workplace low back pain (LBP) with quantified job physical exposure have been performed. There are few prospective epidemiological studies for LBP occupational risk factors and reported data generally have few adjustments for many personal and psychosocial factors. Methods/design A multi-center prospective cohort study has been incepted to quantify risk factors for LBP and potentially develop improved methods for designing and analyzing jobs. Due to the subjectivity of LBP, six measures of LBP are captured: 1) any LBP, 2) LBP ≥ 5/10 pain rating, 3) LBP with medication use, 4) LBP with healthcare provider visits, 5) LBP necessitating modified work duties and 6) LBP with lost work time. Workers have thus far been enrolled from 30 different employment settings in 4 diverse US states and performed widely varying work. At baseline, workers undergo laptop-administered questionnaires, structured interviews, and two standardized physical examinations to ascertain demographics, medical history, psychosocial factors, hobbies and physical activities, and current musculoskeletal disorders. All workers’ jobs are individually measured for physical factors and are videotaped. Workers are followed monthly for the development of low back pain. Changes in jobs necessitate re-measure and re-videotaping of job physical factors. The lifetime cumulative incidence of low back pain will also include those with a past history of low back pain. Incident cases will exclude prevalent cases at baseline. Statistical methods planned include survival analyses and logistic regression. Discussion Data analysis of a prospective cohort study of low back pain is underway and has successfully enrolled over 800 workers to date. PMID:23497211
Effects of expectancies and coping on pain-induced motivation to smoke.
Ditre, Joseph W; Heckman, Bryan W; Butts, Emily A; Brandon, Thomas H
2010-08-01
The prevalence of tobacco smoking among persons with recurrent pain is approximately twice that observed in the general population. Smoking has been associated with the development and exacerbation of several chronically painful conditions. Conversely, there is both experimental and cross-sectional evidence that pain is a potent motivator of smoking. A recent study provided the first evidence that laboratory-induced pain could elicit increased craving and produce shorter latencies to smoke (Ditre & Brandon, 2008). To further elucidate interrelations between pain and smoking, and to identify potential targets for intervention, in the current study, we tested whether several constructs derived from social-cognitive theory influence the causal pathway between pain and increased motivation to smoke. Smokers (N = 132) were randomly assigned to 1 of 4 conditions in this 2 x 2 between-subjects experimental design. Results indicated that manipulations designed to (a) challenge smoking-related outcome expectancies for pain reduction and (b) enhance pain-related coping produced decreased urge ratings and increased latencies to smoke, relative to controls. An unexpected interaction effect revealed that although each manipulation was sufficient to reduce smoking urges, the combination was neither additive nor synergistic. These findings were integrated with those of the extant literature to conceptualize and depict a causal pathway between pain and motivation to smoke as moderated by smoking-related outcome expectancies and mediated by the use of pain coping behaviors. Copyright 2010 APA, all rights reserved
Virtual reality and pain management: current trends and future directions
Li, Angela; Montaño, Zorash; Chen, Vincent J; Gold, Jeffrey I
2011-01-01
SUMMARY Virtual reality (VR) has been used to manage pain and distress associated with a wide variety of known painful medical procedures. In clinical settings and experimental studies, participants immersed in VR experience reduced levels of pain, general distress/unpleasantness and report a desire to use VR again during painful medical procedures. Investigators hypothesize that VR acts as a nonpharmacologic form of analgesia by exerting an array of emotional affective, emotion-based cognitive and attentional processes on the body’s intricate pain modulation system. While the exact neurobiological mechanisms behind VR’s action remain unclear, investigations are currently underway to examine the complex interplay of cortical activity associated with immersive VR. Recently, new applications, including VR, have been developed to augment evidenced-based interventions, such as hypnosis and biofeedback, for the treatment of chronic pain. This article provides a comprehensive review of the literature, exploring clinical and experimental applications of VR for acute and chronic pain management, focusing specifically on current trends and recent developments. In addition, we propose mechanistic theories highlighting VR distraction and neurobiological explanations, and conclude with new directions in VR research, implications and clinical significance. PMID:21779307
Virtual reality and pain management: current trends and future directions.
Li, Angela; Montaño, Zorash; Chen, Vincent J; Gold, Jeffrey I
2011-03-01
Virtual reality (VR) has been used to manage pain and distress associated with a wide variety of known painful medical procedures. In clinical settings and experimental studies, participants immersed in VR experience reduced levels of pain, general distress/unpleasantness and report a desire to use VR again during painful medical procedures. Investigators hypothesize that VR acts as a nonpharmacologic form of analgesia by exerting an array of emotional affective, emotion-based cognitive and attentional processes on the body's intricate pain modulation system. While the exact neurobiological mechanisms behind VR's action remain unclear, investigations are currently underway to examine the complex interplay of cortical activity associated with immersive VR. Recently, new applications, including VR, have been developed to augment evidenced-based interventions, such as hypnosis and biofeedback, for the treatment of chronic pain. This article provides a comprehensive review of the literature, exploring clinical and experimental applications of VR for acute and chronic pain management, focusing specifically on current trends and recent developments. In addition, we propose mechanistic theories highlighting VR distraction and neurobiological explanations, and conclude with new directions in VR research, implications and clinical significance.
Breser, Maria L; Motrich, Ruben D; Sanchez, Leonardo R; Rivero, Virginia E
2017-01-01
Experimental autoimmune prostatitis (EAP) is an autoimmune inflammatory disease of the prostate characterized by peripheral prostate-specific autoimmune responses associated with prostate inflammation. EAP is induced in rodents upon immunization with prostate antigens (PAg) plus adjuvants and shares important clinical and immunological features with the human disease chronic prostatitis/chronic pelvic pain syndrome (CP/CPPS). EAP was induced in young NOD, C57BL/6, and BALB/c male mice by immunization with PAg plus complete Freund́s adjuvant. Tactile allodynia was assessed using Von Frey fibers as a measure of pelvic pain at baseline and at different time points after immunization. Using conventional histology, immunohistochemistry, FACS analysis, and protein arrays, an interstrain comparative study of prostate cell infiltration and inflammation was performed. Chronic pelvic pain development was similar between immunized NOD and C57BL/6 mice, although the severity of leukocyte infiltration was greater in the first case. Coversely, minimal prostate cell infiltration was observed in immunized BALB/c mice, who showed no pelvic pain development. Increased numbers of mast cells, mostly degranulated, were detected in prostate samples from NOD and C57BL/6 mice, while lower total counts and resting were observed in BALB/c mice. Prostate tissue from NOD mice revealed markedly increased expression levels of inflammatory cytokines, chemokines, adhesion molecules, vascular endothelial growth factor, and metalloproteinases. Similar results, but to a lesser extent, were observed when analyzing prostate tissue from C57BL/6 mice. On the contrary, the expression of the above mediators was very low in prostate tissue from immunized BALB/c mice, showing significantly slight increments only for CXCL1 and IL4. Our results provide new evidence indicating that NOD, C57BL/6, and BALB/c mice develop different degrees of chronic pelvic pain, type, and amount of prostate cell infiltration
Social interaction and pain: An arctic expedition.
Block, Per; Heathcote, Lauren C; Burnett Heyes, Stephanie
2018-01-01
Complex human behaviour can only be understood within its social environment. However, disentangling the causal links between individual outcomes and social network position is empirically challenging. We present a research design in a closed real-world setting with high-resolution temporal data to understand this interplay within a fundamental human experience - physical pain. Study participants completed an isolated 3-week hiking expedition in the Arctic Circle during which they were subject to the same variation in environmental conditions and only interacted amongst themselves. Adolescents provided daily ratings of pain and social interaction partners. Using longitudinal network models, we analyze the interplay between social network position and the experience of pain. Specifically, we test whether experiencing pain is linked to decreasing popularity (increasing isolation), whether adolescents prefer to interact with others experiencing similar pain (homophily), and whether participants are increasingly likely to report similar pain as their interaction partners (contagion). We find that reporting pain is associated with decreasing popularity - interestingly, this effect holds for males only. Further exploratory analyses suggest this is at least partly driven by males withdrawing from contact with females when in pain, enhancing our understanding of pain and masculinity. Contrary to recent experimental and clinical studies, we found no evidence of pain homophily or contagion in the expedition group. Copyright © 2018 Elsevier Ltd. All rights reserved.
Moon, Jong Hoon; Jung, Jin-Hwa; Won, Young Sik; Cho, Hwi-Young
2017-01-01
[Purpose] The purpose of this study was to analyze the effect of Graston Technique on hamstring extensibility and pain intensity in patients with nonspecific low back pain. [Subjects and Methods] Twenty-four patients with nonspecific low back pain (27–46 years of age) enrolled in the study. All participants were randomly assigned to one of two groups: Graston technique group (n=12) and a static stretching group (n=12). The Graston Technique was used on the hamstring muscles of the experimental group, while the static stretching group performed static stretching. Hamstring extensibility was recorded using the sit and reach test, and a visual analog scale was used to measure pain intensity. [Results] Both groups showed a significant improvement after intervention. In comparison to the static stretching group, the Graston technique group had significantly more improvement in hamstring extensibility. [Conclusion] The Graston Technique is a simple and effective intervention in nonspecific low back pain patients to improve hamstring extensibility and lower pain intensity, and it would be beneficial in clinical practice. PMID:28265144
Moon, Jong Hoon; Jung, Jin-Hwa; Won, Young Sik; Cho, Hwi-Young
2017-02-01
[Purpose] The purpose of this study was to analyze the effect of Graston Technique on hamstring extensibility and pain intensity in patients with nonspecific low back pain. [Subjects and Methods] Twenty-four patients with nonspecific low back pain (27-46 years of age) enrolled in the study. All participants were randomly assigned to one of two groups: Graston technique group (n=12) and a static stretching group (n=12). The Graston Technique was used on the hamstring muscles of the experimental group, while the static stretching group performed static stretching. Hamstring extensibility was recorded using the sit and reach test, and a visual analog scale was used to measure pain intensity. [Results] Both groups showed a significant improvement after intervention. In comparison to the static stretching group, the Graston technique group had significantly more improvement in hamstring extensibility. [Conclusion] The Graston Technique is a simple and effective intervention in nonspecific low back pain patients to improve hamstring extensibility and lower pain intensity, and it would be beneficial in clinical practice.
Modulation of pain by estrogens.
Craft, Rebecca M
2007-11-01
It has become increasingly apparent that women suffer a disproportionate amount of pain during their lifetime compared to men. Over the past 15 years, a growing number of studies have suggested a variety of causes for this sex difference, from cellular to psychosocial levels of analysis. From a biological perspective, sexual differentiation of pain appears to occur similarly to sexual differentiation of other phenomena: it results in large part from organizational and activational effects of gonadal steroid hormones. The focus of this review is the activational effects of a single group of ovarian hormones, the estrogens, on pain in humans and animals. The effects of estrogens (estradiol being the most commonly examined) on experimentally induced acute pain vs. clinical pain are summarized. For clinical pain, the review is limited to a few syndromes for which there is considerable evidence for estrogenic involvement: migraine, temporomandibular disorder (TMD) and arthritis. Because estrogens can modulate the function of the nervous, immune, skeletal, and cardiovascular systems, estrogenic modulation of pain is an exceedingly complex, multi-faceted phenomenon, with estrogens producing both pro- and antinociceptive effects that depend on the extent to which each of these systems of the body is involved in a particular type of pain. Forging a more complete understanding of the myriad ways that estrogens can ameliorate vs. facilitate pain will enable us to better prevent and treat pain in both women and men.
Mansilla-Ferragut, Pilar; Fernández-de-Las Peñas, César; Alburquerque-Sendín, Francisco; Cleland, Joshua A; Boscá-Gandía, Juan José
2009-02-01
The purpose of this study was to investigate the effects of a spinal thrust manipulation directed to the upper cervical segments (atlanto-occipital joint) on active mouth opening and pressure pain sensitivity in a trigeminal nerve innervated region (sphenoid bone) in women with mechanical neck pain. Thirty-seven women, ages 21 to 50 years old (mean age, 35 +/- 8 years) with mechanical neck pain were recruited for this study. Participants were randomly assigned into 1 of 2 groups as follows: an experimental group that received a spinal manipulation of the atlanto-occipital joint and a control group that received a manual contact placebo intervention. Outcomes collected were assessed pretreatment and 5 minutes posttreatment by an assessor blinded to the treatment allocation and included active mouth opening and pressure pain thresholds (PPTs) over both sides of the sphenoid bone. A 2-way repeated measures analysis of variance (ANOVA) with time (pre-post) as the within subjects variable and group (control, experimental) as the between subjects variable was used to examine the effects of the intervention. The hypothesis of interest was group-time interaction. The ANOVA showed a significant effect for time (F = 23.1; P < .001) and an interaction between group and time (F = 37.7; P < .001) for active mouth opening as follows: the experimental group showed a greater improvement when compared to the control group. A large positive within-group effect size (d > 1.5) for the experimental group, whereas a negative medium within-group effect size (d = -0.5) for the control group were identified. The ANOVA showed a significant interaction between group and time (F = 14.4; P < .001) for PPT levels at the sphenoid bone as follows: the experimental group showed a greater improvement when compared to the control group. A medium positive within-group effect size (d = -0.5) for the experimental group, whereas a negative medium within-group effect size (d = -0.5) for the control group
Weissman-Fogel, Irit; Granovsky, Yelena; Crispel, Yonathan; Ben-Nun, Alon; Best, Lael Anson; Yarnitsky, David; Granot, Michal
2009-06-01
Recent evidence points to an association between experimental pain measures obtained preoperatively and acute postoperative pain (POP). We hypothesized that pain temporal summation (TS) might be an additional predictor for POP insofar as it represents the neuroplastic changes that occur in the central nervous system following surgery. Therefore, a wide range of psychophysical tests (TS to heat and mechanical repetitive stimuli, pain threshold, and suprathreshold pain estimation) and personality tests (pain catastrophizing and anxiety levels) were administered prior to thoracotomy in 84 patients. POP ratings were evaluated on the 2nd and 5th days after surgery at rest (spontaneous pain) and in response to activity (provoked pain). Linear regression models revealed that among all assessed variables, enhanced TS and higher pain scores for mechanical stimulation were significantly associated with greater provoked POP intensity (overall r2 = 0.225, P = .008). Patients who did not demonstrate TS to both modalities reported lower scores of provoked POP as compared with patients who demonstrated TS in response to at least 1 modality (F = 4.59 P = .013). Despite the moderate association between pain catastrophizing and rest POP, none of the variables predicted the spontaneous POP intensity. These findings suggest that individual susceptibility toward a greater summation response may characterize patients who are potentially vulnerable to augmented POP. This study proposed the role of pain temporal summation assessed preoperatively as a significant psychophysical predictor for acute postoperative pain intensity. The individual profile of enhanced pain summation is associated with the greater likelihood of higher postoperative pain scores.
Hsieh, Annie Y; Tripp, Dean A; Ji, Li-Jun
2011-09-01
This study's aim was to examine the influence of ethnic concordance on Chinese participants' pain report and nonverbal pain expression in a laboratory setting. Participants (n=102) were exposed to a cold pressor task under 1 of 2 conditions: Chinese milieu (n=52; participants exposed to Chinese experimenters and language), or European Canadian milieu (n=50; participants exposed to Euro-Canadian experimenters and English language). A reference group with 86 Euro-Canadian participants, exposed to the Euro-Canadian milieu only, was included for comparison. The Chinese groups did not differ on pain intensity during the pain task. However, Chinese participants in the Chinese milieu reported significantly higher affective pain and displayed more nonverbal behaviour of pain than the Chinese participants in the Euro-Canadian milieu. In addition, compared to the Euro-Canadian group, both Chinese groups reported higher pain intensity during the pain task and greater affective pain after immersion. The results demonstrated that an ethnically concordant milieu is associated with increased nonverbal pain displays and affective pain report. These findings suggest that research on ethnic disparities in pain treatment should examine ethnic concordance between observer and individual in pain. Copyright © 2011 International Association for the Study of Pain. Published by Elsevier B.V. All rights reserved.
Current methodological approaches in conditioned pain modulation assessment in pediatrics
Hwang, Philippe S; Ma, My-Linh; Spiegelberg, Nora; Ferland, Catherine E
2017-01-01
Conditioned pain modulation (CPM) paradigms have been used in various studies with healthy and non-healthy adult populations in an attempt to elucidate the mechanisms of pain processing. However, only a few studies so far have applied CPM in pediatric populations. Studies finding associations with chronic pain conditions suggest that deficiencies in underlying descending pain pathways may play an important role in the development and persistence of pain early in life. Twelve studies were identified using a PubMed search which examine solely pediatric populations, and these are reviewed with regard to demographics studied, methodological approaches, and conclusions reached. This review aimed to provide both clinicians and researchers with a brief overview of the current state of research regarding the use of CPM in children and adolescents, both healthy and clinical patients. The implications of CPM in experimental and clinical settings and its potential to aid in refining considerations to individualize treatment of pediatric pain syndromes will be discussed. PMID:29263694
Pain perception in major depressive disorder: a neurophysiological case-control study.
Zambito Marsala, Sandro; Pistacchi, Michele; Tocco, Pierluigi; Gioulis, Manuela; Fabris, Federico; Brigo, Francesco; Tinazzi, Michele
2015-10-15
Depression and pain may sometimes be related conditions. Occasionally, depression may be associated with physical symptoms, such as back pain and headache. Moreover, depression may impair the subjective response to pain and is likely to influence the pain feeling. Conversely, chronic pain may represent an emotional condition as well as physical sensation, and can influence both the mood and behaviour. To better understand the relationship between pain and depression, we therefore assessed the pain threshold and the tolerance pain threshold in patients with depressive disorders. We conducted a case-control study and selected patients who had recently received a diagnosis of major depression (DSM-IV), before treatment, and without any significant pain complaints. Age- and sex-matched healthy controls were also included. Tactile and pain thresholds were assessed in all subjects through an electrical stimulation test. All results were compared between the groups. 27 patients and 27 age-matched healthy controls were included in the study. Tactile, pain and tolerance thresholds were evaluated in all subjects. The pain threshold and pain tolerance were lower in patients with major depression than controls. All differences were statistically significant (p<0.05). These results suggest the abnormal processing of pain stimuli in depressive disorders. Copyright © 2015 Elsevier B.V. All rights reserved.
Pain and sex hormones: a review of current understanding.
Maurer, Adrian J; Lissounov, Alexei; Knezevic, Ivana; Candido, Kenneth D; Knezevic, Nebojsa Nick
2016-01-01
Multiple epidemiologic studies have demonstrated an increased prevalence for women in several chronic pain disorders. Clinical and experimental investigations have consistently demonstrated sex-specific differences in pain sensitivity and pain threshold. Even though the underlying mechanisms responsible for these differences have not yet been elucidated, the logical possibility of gonadal hormone influence on nociceptive processing has garnered recent attention. In this review, we evaluated the complex literature regarding gonadal hormones and their influence on pain perception. We reviewed the numerous functions of gonadal hormones, discussed the influence of these hormones on several common chronic pain syndromes (migraine, tension and cluster headaches, fibromyalgia, temporomandibular syndrome, rheumatoid arthritis and back pain, among others), and have attempted to draw conclusions from the available data.
Wilder-Smith, Oliver Hamilton; Schreyer, Tobias; Scheffer, Gert Jan; Arendt-Nielsen, Lars
2010-06-01
Chronic pain is common and undesirable after surgery. Progression from acute to chronic pain involves altered pain processing. The authors studied relationships between presence of chronic pain versus preoperative descending pain control (diffuse noxious inhibitory controls; DNICs) and postoperative persistence and spread of skin and deep tissue hyperalgesia (change in electric/pressure pain tolerance thresholds; ePTT/pPTT) up to 6 months postoperatively. In 20 patients undergoing elective major abdominal surgery under standardized anesthesia, we determined ePTT/pPTT (close to [abdomen] and distant from [leg] incision), eDNIC/pDNIC (change in ePTT/pPTT with cold pressor pain task; only preoperatively), and a 100 mm long pain visual analogue scale (VAS) (0 mm = no pain, 100 mm = worst pain imaginable), both at rest and on movement preoperatively, and 1 day and 1, 3, and 6 months postoperatively. Patients reporting chronic pain 6 months postoperatively had more abdominal and leg skin hyperalgesia over the postoperative period. More inhibitory preoperative eDNIC was associated with less late postoperative pain, without affecting skin hyperalgesia. More inhibitory pDNIC was linked to less postoperative leg deep tissue hyperalgesia, without affecting pain VAS. This pilot study for the first time links chronic pain after surgery, poorer preoperative inhibitory pain modulation (DNIC), and greater postoperative degree, persistence, and spread of hyperalgesia. If confirmed, these results support the potential clinical utility of perioperative pain processing testing.
Van Oosterwijck, Jessica; Nijs, Jo; Meeus, Mira; Truijen, Steven; Craps, Julie; Van den Keybus, Nick; Paul, Lorna
2011-01-01
Chronic whiplash is a debilitating condition characterized by increased sensitivity to painful stimuli, maladaptive illness beliefs, inappropriate attitudes, and movement dysfunctions. Previous work in people with chronic low back pain and chronic fatigue syndrome indicates that pain neurophysiology education is able to improve illness beliefs and attitudes as well as movement performance. This single-case study (A-B-C design) with six patients with chronic whiplash associated disorders (WAD) was aimed at examining whether education about the neurophysiology of pain is accompanied by changes in symptoms, daily functioning, pain beliefs, and behavior. Periods A and C represented assessment periods, while period B consisted of the intervention (pain neurophysiology education). Results showed a significant decrease in kinesiophobia (Tampa Scale for Kinesiophobia), the passive coping strategy of resting (Pain Coping Inventory), self-rated disability (Neck Disability Index), and photophobia (WAD Symptom List). At the same time, significantly increased pain pressure thresholds and improved pain-free movement performance (visual analog scale on Neck Extension Test and Brachial Plexus Provocation Test) were established. Although the current results need to be verified in a randomized, controlled trial, they suggest that education about the physiology of pain is able to increase pain thresholds and improve pain behavior and pain-free movement performance in patients with chronic WAD.
Chronic pain in multiple sclerosis: A 10-year longitudinal study.
Young, Jamie; Amatya, Bhasker; Galea, Mary P; Khan, Fary
2017-07-01
Pain is a common symptom associated with multiple sclerosis (MS), and has lasting effects on an individual's functional capacity and quality of life. A wide range of prevalence rates of pain (between 23% and 90%)have been reported in MS and this is mainly due to the methodological differences amongst the studies such as variability in patient sources, method of sampling and the definition of pain used. Chronic pain in MS, defined as pain lasting for greater than 3-6 months, can have a significant impact on their biopsychosocial health, including negative impact on activities of daily living, relationships and social participation. The long-term course of MS-related pain and its impact in an Australian cohort over a 7-year period has been investigated earlier. The aim of this longitudinal study was to describe the impact of chronic pain, pain-related disability and carer burden in persons with MS over a 10-year period. The aim of this longitudinal study was to describe the impact of chronic pain, pain-related disability and carer burden in persons with MS over a 10-year period. This was a prospective longitudinal study conducted at the Rehabilitation Department of Royal Melbourne Hospital (RMH), a tertiary referral hospital in Victoria and Australia. The source of participants was from the RMH MS database and contains detailed MS patient information including demographic data, diagnosis details (using McDonald's criteria), pain characteristics. Structured face-face interviews and validated measures were used, which include the visual analogue scale (VAS); chronic pain grade (CPG); the assessment of quality of life (AQoL) and the carer strain index (CSI). The mean age of the participants (n=70) was 55.3 years and majority (70%) were female. The mean age of the participants (n=70) was 55.3 years and majority (70%) were female. The findings show that over time (10 years), participants report having greater bilateral bodily pain and greater description of pain as 'worse
Goodin, Burel R.; Glover, Toni L.; Sotolongo, Adriana; King, Christopher D.; Sibille, Kimberly T.; Herbert, Matthew S.; Cruz-Almeida, Yenisel; Sanden, Shelley H.; Staud, Roland; Redden, David T.; Bradley, Laurence A.; Fillingim, Roger B.
2012-01-01
Dispositional optimism has been shown to beneficially influence various experimental and clinical pain experiences. One possibility that may account for decreased pain sensitivity among individuals who report greater dispositional optimism is less use of maladaptive coping strategies like pain catastrophizing, a negative cognitive/affective response to pain. An association between dispositional optimism and conditioned pain modulation (CPM), a measure of endogenous pain inhibition, has previously been reported. However, it remains to be determined whether dispositional optimism is also associated with temporal summation (TS), a measure of endogenous pain facilitation. The current study examined whether pain catastrophizing mediated the association between dispositional optimism and TS among 140 older, community-dwelling adults with symptomatic knee osteoarthritis. Individuals completed measures of dispositional optimism and pain catastrophizing. TS was then assessed using a tailored heat pain stimulus on the forearm. Greater dispositional optimism was significantly related to lower levels of pain catastrophizing and TS. Bootstrapped confidence intervals revealed that less pain catastrophizing was a significant mediator of the relation between greater dispositional optimism and diminished TS. These findings support the primary role of personality characteristics such as dispositional optimism in the modulation of pain outcomes by abatement of endogenous pain facilitation and less use of catastrophizing. PMID:23218934
Audiovisual distraction for pain relief in paediatric inpatients: A crossover study.
Oliveira, N C A C; Santos, J L F; Linhares, M B M
2017-01-01
Pain is a stressful experience that can have a negative impact on child development. The aim of this crossover study was to examine the efficacy of audiovisual distraction for acute pain relief in paediatric inpatients. The sample comprised 40 inpatients (6-11 years) who underwent painful puncture procedures. The participants were randomized into two groups, and all children received the intervention and served as their own controls. Stress and pain-catastrophizing assessments were initially performed using the Child Stress Scale and Pain Catastrophizing Scale for Children, with the aim of controlling these variables. The pain assessment was performed using a Visual Analog Scale and the Faces Pain Scale-Revised after the painful procedures. Group 1 received audiovisual distraction before and during the puncture procedure, which was performed again without intervention on another day. The procedure was reversed in Group 2. Audiovisual distraction used animated short films. A 2 × 2 × 2 analysis of variance for 2 × 2 crossover study was performed, with a 5% level of statistical significance. The two groups had similar baseline measures of stress and pain catastrophizing. A significant difference was found between periods with and without distraction in both groups, in which scores on both pain scales were lower during distraction compared with no intervention. The sequence of exposure to the distraction intervention in both groups and first versus second painful procedure during which the distraction was performed also significantly influenced the efficacy of the distraction intervention. Audiovisual distraction effectively reduced the intensity of pain perception in paediatric inpatients. The crossover study design provides a better understanding of the power effects of distraction for acute pain management. Audiovisual distraction was a powerful and effective non-pharmacological intervention for pain relief in paediatric inpatients. The effects were
Social transfer of pain in mice
Smith, Monique L.; Hostetler, Caroline M.; Heinricher, Mary M.; Ryabinin, Andrey E.
2016-01-01
A complex relationship exists between the psychosocial environment and the perception and experience of pain, and the mechanisms of the social communication of pain have yet to be elucidated. The present study examined the social communication of pain and demonstrates that “bystander” mice housed and tested in the same room as mice subjected to inflammatory pain or withdrawal from morphine or alcohol develop corresponding hyperalgesia. Olfactory cues mediate the transfer of hyperalgesia to the bystander mice, which can be measured using mechanical, thermal, and chemical tests. Hyperalgesia in bystanders does not co-occur with anxiety or changes in corticosterone and cannot be explained by visually dependent emotional contagion or stress-induced hyperalgesia. These experiments reveal the multifaceted relationship between the social environment and pain behavior and support the use of mice as a model system for investigating these factors. In addition, these experiments highlight the need for proper consideration of how experimental animals are housed and tested. PMID:27774512
Pain and learning in primary school: a population-based study.
Kosola, Silja; Mundy, Lisa K; Sawyer, Susan M; Canterford, Louise; van der Windt, Danielle A; Dunn, Kate M; Patton, George C
2017-09-01
Despite the frequency of pain among children, little is known about its effects on learning and school outcomes. The objective of this study was to quantify the association of pain and academic achievement while taking into account the presence of co-occurring emotional symptoms. A population-based stratified random sample of 1239 students aged 8 to 9 years from primary schools in Melbourne, Australia, was recruited for the Childhood to Adolescence Transition Study. Children indicated sites of pain that had lasted for a day or longer in the past month using a pain manikin. Depressive- and anxiety-related symptoms were assessed using child-reported items. National assessment results for reading and numeracy were used to measure academic achievement. Sixty-five percent of children reported pain in at least 1 body site and 16% reported chronic pain. Increasing number of pain sites was associated with poorer reading scores in a dose-response fashion (β = -3.1; 95% confidence interval -4.9 to -1.3; P < 0.001). The association was only partly attenuated when adjusting for emotional symptoms (β = -2.6; 95% confidence interval -4.5 to -0.8; P < 0.001) and was not moderated by emotional symptoms. Children with chronic pain were a year behind their peers in both reading and numeracy. Among primary school students, pain was associated with lower reading scores even after adjusting for the presence of emotional symptoms. Although population-based longitudinal studies will be required to ascertain consistency and possible causality, grounds exist for considering pain and emotional symptoms in the assessment of children with reading difficulties.
A preliminary study on how hypohydration affects pain perception.
Bear, Tracey; Philipp, Michael; Hill, Stephen; Mündel, Toby
2016-05-01
Chronic pain is a prevalent health issue with one in five people suffering from some form of chronic pain, with loss of productivity and medical costs of chronic pain considerable. However, the treatment of pain can be difficult, as pain perception is complex and can be affected by factors other than tissue damage. This study investigated the effect of hypohydration (mild, voluntary dehydration from ∼24 h of limiting fluid intake, mimicking someone drinking less than usual) on a person's pain perception. Seventeen healthy males (age 27 ± 5 years) visited the laboratory on three occasions, once as a familiarization and then twice again while either euhydrated (urine specific gravity: 1.008 ± 0.005) or hypohydrated (urine specific gravity: 1.024 ± 0.003, and -1.4 ± 0.9% body mass). Each visit, they performed a cold pressor test, where their feet were placed in cold water (0-3 °C) for a maximum of 4 min. Measures of hydration status, pain sensitivity, pain threshold, and catastrophization were taken. We found that hypohydration predicted increased pain sensitivity (β = 0.43), trait pain catastrophizing, and baseline pain sensitivity (β = 0.37 and 0.47, respectively). These results are consistent with previous research, and suggest that a person's hydration status may be an important factor in their perception of acute pain. © 2016 Society for Psychophysiological Research.
Spindola, Humberto M; Grando, Rogério; Figueiredo, Mariana C; Basting, Rosana; Queiroz, N C A; de Fátima, Ângelo; de Carvalho, João E; Wang, Zaijie J; Foglio, M A
2017-06-05
Pterodon genus fruits are commercially available at the Brazilian medicinal market used in folk medicine due to their anti-inflammatory, analgesic, and anti-rheumatic effects. Previous studies demonstrated that furanditerpenes possessing vouacapan skeleton, isolated from Pterodon genus, possess expressive antinociceptive activities, with promising moiety for the development of new analgesic products. The antinociceptive properties of compounds 6α,7β-6α-hidroxivouacapan-7β-17β-lactone (HVL) and 6α-oxovouacapan-7β-17β-lactone (OVL), semi-synthetic analogues of furanditerpenes previously reported as analgesic agents were evaluated on animal experimental models (Spindola et al., 2010, 2011). The chemical-induced pain methods used in the present work, demonstrated for the first time that both compounds HVL and OVL have potential as important templates for the development of chronic pain control drugs. The main findings of this work were that both compounds were: effective in the writhing test; reduced paw edema in the carrageenan test; effective in the inflammatory phase of the formalin test corroborating their activity against inflammatory pain conditions; effective on reducing pain through the stimulation of vanilloid receptors sensible to capsaicin (an important pathway for chronic pain maintenance); reduced the pain stimulus caused by PGE 2 injection (a pathway involved in chronic pain hypersensitivity); effective on decreasing mechanical allodynia in the CFA-model, demonstrating their potential use against chronic pain disorders. Copyright © 2017 Elsevier B.V. All rights reserved.
Haghighat, Shila; Mashayekhi Asl, Mahboobeh
2016-08-01
Several nonsurgical and surgical treatment modalities are available for patients with chronic coccydynia, with controversial results. Extracorporeal shock wave therapy (ECSWT) is effective in the treatment of many musculoskeletal disorders; however, it has not been tested for chronic coccydynia. We performed the current study to determine the effects of ECSWT on pain in patients with chronic coccydynia. This quasi-interventional clinical study included 10 patients with chronic coccydynia without acute fracture. All the patients received ECSWT with a radial probe delivering 3,000 shock waves of 2 bar per session at 21 Hz frequency directed to the coccyx. Each patient received four sessions of ECSWT at one-week intervals. The pain severity was recorded according to the visual analog scale (VAS) at one, two, three, and four weeks after initiation of therapy. The VAS score was also evaluated at one and six months after ending the therapy. Most of the participants were women (90.0%), and the participants' mean age was 39.1 ± 9.1 (ranging from 28 to 52) years. The VAS score did not decrease significantly seven months after therapy when compared to baseline (3.3 ± 3.6 vs. 7.3 ± 2.1; P = 0.011). However, the VAS score at two months (2.6 ± 2.9 vs. 7.3 ± 2.1; P = 0.007) and at four weeks (3.2 ± 2.8 vs. 7.3 ± 2.1; P = 0.007) significantly decreased when compared to baseline. The decrease in VAS scores was not persistent after cessation of the therapy. ECSWT is an effective modality in relieving the pain intensity in patients with refractory chronic coccydynia for the early period after intervention.
A PROSPECTIVE STUDY OF CHRONIC PAIN AFTER THORACIC SURGERY
Bayman, Emine Ozgur; Parekh, Kalpaj R.; Keech, John; Selte, Atakan; Brennan, Timothy J.
2017-01-01
Background The goal of this study was to detect the predictors of chronic pain at 6 months after thoracic surgery from a comprehensive evaluation of demographic, psychosocial, and surgical factors. Methods Thoracic surgery patients were enrolled 1 week before surgery and followed-up 6 months post-surgery in this prospective, observational study. Comprehensive psychosocial measurements were assessed before surgery. The presence and severity of pain was assessed at 3 and 6 months after surgery. One-hundred seven patients were assessed during the first 3 days after surgery and 99 (30 thoracotomy and 69 video-assisted thoracoscopic surgery, thoracoscopy) patients completed the 6 months follow-up. Patients with vs without chronic pain related to thoracic surgery at 6 months were compared. Results Both incidence (p = 0.37) and severity (p = 0.97) of surgery-related chronic pain at 6 months were similar after thoracotomy (33%, 95% confidence interval [CI]: 17% to 53%, 3.3 ± 2.1) and thoracoscopy (25%, 95% CI: 15% to 36%, 3.3 ± 1.7). Both frequentist and Bayesian multivariate models revealed that severity of acute pain (numerical rating scale, 0–10) is the measure associated with chronic pain related to thoracic surgery. Psychosocial factors and quantitative sensory testing were not predictive. Conclusions There was no difference in the incidence and severity of chronic pain at 6 months in patients undergoing thoracotomy versus thoracoscopy. Unlike other post-surgical pain conditions, none of the pre-operative psychosocial measurements were associated with chronic pain after thoracic surgery. PMID:28248713
Emerging Relationships between Exercise, Sensory Nerves, and Neuropathic Pain
Cooper, Michael A.; Kluding, Patricia M.; Wright, Douglas E.
2016-01-01
The utilization of physical activity as a therapeutic tool is rapidly growing in the medical community and the role exercise may offer in the alleviation of painful disease states is an emerging research area. The development of neuropathic pain is a complex mechanism, which clinicians and researchers are continually working to better understand. The limited therapies available for alleviation of these pain states are still focused on pain abatement and as opposed to treating underlying mechanisms. The continued research into exercise and pain may address these underlying mechanisms, but the mechanisms which exercise acts through are still poorly understood. The objective of this review is to provide an overview of how the peripheral nervous system responds to exercise, the relationship of inflammation and exercise, and experimental and clinical use of exercise to treat pain. Although pain is associated with many conditions, this review highlights pain associated with diabetes as well as experimental studies on nerve damages-associated pain. Because of the global effects of exercise across multiple organ systems, exercise intervention can address multiple problems across the entire nervous system through a single intervention. This is a double-edged sword however, as the global interactions of exercise also require in depth investigations to include and identify the many changes that can occur after physical activity. A continued investment into research is necessary to advance the adoption of physical activity as a beneficial remedy for neuropathic pain. The following highlights our current understanding of how exercise alters pain, the varied pain models used to explore exercise intervention, and the molecular pathways leading to the physiological and pathological changes following exercise intervention. PMID:27601974
Effect of expectation on pain assessment of lower- and higher-intensity stimuli.
Ružić, Valentina; Ivanec, Dragutin; Modić Stanke, Koraljka
2017-01-01
Pain modulation via expectation is a well-documented phenomenon. So far it has been shown that expectations about effectiveness of a certain treatment enhance the effectiveness of different analgesics and of drug-free pain treatments. Also, studies demonstrate that people assess same-intensity stimuli differently, depending on the experimentally induced expectations regarding the characteristics of the stimuli. Prolonged effect of expectation on pain perception and possible symmetry in conditions of lower- and higher-intensity stimuli is yet to be studied. Aim of this study is to determine the effect of expectation on the perception of pain experimentally induced by the series of higher- and lower-intensity stimuli. 192 healthy participants were assigned to four experimental groups differing by expectations regarding the intensity of painful stimuli series. Expectations of two groups were congruent with actual stimuli; one group expected and received lower-intensity stimuli and the other expected and received higher-intensity stimuli. Expectations of the remaining two groups were not congruent with actual stimuli; one group expected higher-intensity stimuli, but actually received lower-intensity stimuli while the other group expected lower-intensity stimuli, but in fact received higher-intensity ones. Each group received a series of 24 varied-intensity electrical stimuli rated by the participants on a 30° intensity scale. Expectation manipulation had statistically significant effect on pain intensity assessment. When expecting lower-intensity stimuli, the participants underestimated pain intensity and when expecting higher-intensity stimuli, they overestimated pain intensity. The effect size of expectations upon pain intensity assessment was equal for both lower- and higher-intensity stimuli. The obtained results imply that expectation manipulation can achieve the desired effect of decreasing or increasing both slight and more severe pain for a longer period of
Van Oosterwijck, Jessica; Meeus, Mira; Paul, Lorna; De Schryver, Mieke; Pascal, Aurelie; Lambrecht, Luc; Nijs, Jo
2013-10-01
There is evidence that education on pain physiology can have positive effects on pain, disability, and catastrophization in patients with chronic musculoskeletal pain disorders. A double-blind randomized controlled trial (RCT) was performed to examine whether intensive pain physiology education is also effective in fibromyalgia (FM) patients, and whether it is able to influence the impaired endogenous pain inhibition of these patients. Thirty FM patients were randomly allocated to either the experimental (receiving pain physiology education) or the control group (receiving pacing self-management education). The primary outcome was the efficacy of the pain inhibitory mechanisms, which was evaluated by spatially accumulating thermal nociceptive stimuli. Secondary outcome measures included pressure pain threshold measurements and questionnaires assessing pain cognitions, behavior, and health status. Assessments were performed at baseline, 2 weeks, and 3 months follow-up. Repeated measures ANOVAS were used to reveal possible therapy effects and effect sizes were calculated. After the intervention the experimental group had improved knowledge of pain neurophysiology (P<0.001). Patients from this group worried less about their pain in the short term (P=0.004). Long-term improvements in physical functioning (P=0.046), vitality (P=0.047), mental health (P<0.001), and general health perceptions (P<0.001) were observed. In addition, the intervention group reported lower pain scores and showed improved endogenous pain inhibition (P=0.041) compared with the control group. These results suggest that FM patients are able to understand and remember the complex material about pain physiology. Pain physiology education seems to be a useful component in the treatment of FM patients as it improves health status and endogenous pain inhibition in the long term.
Effects of LLLT for pain: a clinical study on different pain types
NASA Astrophysics Data System (ADS)
Tam, Giuseppe
2002-10-01
Objective: The aim of this clinical study is to determine the efficacy of the JR diode laser 904 nm pulsed on pain reduction therapy. Summary Background Data: With respect to pain, the existence of a filter (Rolando's substantia gelatinosa) in the spinal marrow is fundamental. Opening or closing, this filter is able to block transmission of pain impulses to a higher cerebral center. This is in proportion with the A big fibres and C small fibres. The action of the laser influences this mechanism. Additionally, laser interferes in the cytochines (TNf-α , interleukin-1 and interleukin-6) that drive inflammation in the arthritis and are secreted from CD4 e T cells. Low power density laser increases the endorphin synthesis in the dorsal posterior horn of the spinal cord. Besides, laser causes local vasodilatation of the capillaries and an improved circulation of drainage liquids in interstitial space causing an analgesic effect. Methods: Treatment was carried out on 482 cases and 464 patients (274 women and 190 men) in the period between 1987 and 2000. The patients, whose age ranged from 25 to 70, with a mean age of 45 years, were suffering from rheumatic, degenerative and traumatic pathologies as well as cutaneous ulcers. The majority of the patients had been seen by orthopaedists and rheumatologists and had undergone x-ray, ultrasound scanning, TAC, RM examination. All patients had previously received drug-based treatment and/or physiotherapy with poor results. Two thirds were experiencing acute symptomatic pain, while the others presented a chronic pathology with recurrent crises. We used a pulsed JR diode laser, GaAs 904 nm wavelength. Results: Jn the evaluation of the results the following parameters have been considered: disappearance of spontaneous and induced pain, anatomic and functional evaluation of the joints, muscular growth, verbal rating scales, hand dinamometer, patient's pain diary. Very good results were achieved especially with cases of symptomatic
Kutch, Jason J; Labus, Jennifer S; Harris, Richard E; Martucci, Katherine T; Farmer, Melissa A; Fenske, Sonja; Fling, Connor; Ichesco, Eric; Peltier, Scott; Petre, Bogdan; Guo, Wensheng; Hou, Xiaoling; Stephens, Alisa J; Mullins, Chris; Clauw, Daniel J; Mackey, Sean C; Apkarian, A Vania; Landis, J Richard; Mayer, Emeran A
2017-06-01
Chronic pain symptoms often change over time, even in individuals who have had symptoms for years. Studying biological factors that predict trends in symptom change in chronic pain may uncover novel pathophysiological mechanisms and potential therapeutic targets. In this study, we investigated whether brain functional connectivity measures obtained from resting-state functional magnetic resonance imaging at baseline can predict longitudinal symptom change (3, 6, and 12 months after scan) in urologic chronic pelvic pain syndrome. We studied 52 individuals with urologic chronic pelvic pain syndrome (34 women, 18 men) who had baseline neuroimaging followed by symptom tracking every 2 weeks for 1 year as part of the Multidisciplinary Approach to the Study of Chronic Pelvic Pain (MAPP) Research Network study. We found that brain functional connectivity can make a significant prediction of short-term (3 month) pain reduction with 73.1% accuracy (69.2% sensitivity and 75.0% precision). In addition, we found that the brain regions with greatest contribution to the classification were preferentially aligned with the left frontoparietal network. Resting-state functional magnetic resonance imaging measures seemed to be less informative about 6- or 12-month symptom change. Our study provides the first evidence that future trends in symptom change in patients in a state of chronic pain may be linked to functional connectivity within specific brain networks.
Flodin, Pär; Martinsen, Sofia; Altawil, Reem; Waldheim, Eva; Lampa, Jon; Kosek, Eva; Fransson, Peter
2016-01-01
Background: Rheumatoid arthritis (RA) is commonly accompanied by pain that is discordant with the degree of peripheral pathology. Very little is known about the cerebral processes involved in pain processing in RA. Here we investigated resting-state brain connectivity associated with prolonged pain in RA. Methods: 24 RA subjects and 19 matched controls were compared with regard to both behavioral measures of pain perception and resting-resting state fMRI data acquired subsequently to fMRI sessions involving pain stimuli. The resting-state fMRI brain connectivity was investigated using 159 seed regions located in cardinal pain processing brain regions. Additional principal component based multivariate pattern analysis of the whole brain connectivity pattern was carried out in a data driven analysis to localize group differences in functional connectivity. Results: When RA patients were compared to controls, we observed significantly lower pain resilience for pressure on the affected finger joints (i.e., P50-joint) and an overall heightened level of perceived global pain in RA patients. Relative to controls, RA patients displayed increased brain connectivity predominately for the supplementary motor areas, mid-cingulate cortex, and the primary sensorimotor cortex. Additionally, we observed an increase in brain connectivity between the insula and prefrontal cortex as well as between anterior cingulate cortex and occipital areas for RA patients. None of the group differences in brain connectivity were significantly correlated with behavioral parameters. Conclusion: Our study provides experimental evidence of increased connectivity between frontal midline regions that are implicated in affective pain processing and bilateral sensorimotor regions in RA patients. PMID:27014038
The efficacy of cold-gel packing for relieving episiotomy pain - a quasi-randomised control trial.
Lu, Yu-Ying; Su, Mei-Ling; Gau, Meei-Ling; Lin, Kuan-Chia; Au, Heng-Kien
2015-01-01
This study evaluated the effectiveness of cold-gel packing on episiotomy pain among postpartum women who had normal spontaneous deliveries. A quasi-randomised control trial was conducted in a maternity ward of a regional teaching hospital in northern Taiwan. Seventy postpartum women were recruited, choosing to be in either the experimental or control group (35 women per group). Subjects in the experimental group received at least six interventions of cold-gel packing applied to the perineal wound and were provided oral analgesics routinely. The subjects in the control group received oral analgesics routinely. Pain intensity, pain interference on daily activities and satisfaction levels with pain management were assessed using Brief Pain Inventory (BPI) and pain management questionnaire, respectively. The results showed that women in the experimental group reported significantly lower mean pain intensity score, pain interference on daily activities scores at 48 hours post-delivery, and higher level of satisfaction with pain management at 24 and 48 hours post-delivery than the control group after adjusting for demographic and obstetric data. Cold-gel packing on the perineum is a cost-effective, convenient, easy-to-deploy and non-pharmacologic approach to pain reduction, with an overall positive impact on postpartum recovery for parturients.
Themistocleous, Andreas C.; Ramirez, Juan D.; Shillo, Pallai R.; Lees, Jonathan G.; Selvarajah, Dinesh; Orengo, Christine; Tesfaye, Solomon; Rice, Andrew S.C.; Bennett, David L.H.
2016-01-01
Abstract Disabling neuropathic pain (NeuP) is a common sequel of diabetic peripheral neuropathy (DPN). We aimed to characterise the sensory phenotype of patients with and without NeuP, assess screening tools for NeuP, and relate DPN severity to NeuP. The Pain in Neuropathy Study (PiNS) is an observational cross-sectional multicentre study. A total of 191 patients with DPN underwent neurological examination, quantitative sensory testing, nerve conduction studies, and skin biopsy for intraepidermal nerve fibre density assessment. A set of questionnaires assessed the presence of pain, pain intensity, pain distribution, and the psychological and functional impact of pain. Patients were divided according to the presence of DPN, and thereafter according to the presence and severity of NeuP. The DN4 questionnaire demonstrated excellent sensitivity (88%) and specificity (93%) in screening for NeuP. There was a positive correlation between greater neuropathy severity (r = 0.39, P < 0.01), higher HbA1c (r = 0.21, P < 0.01), and the presence (and severity) of NeuP. Diabetic peripheral neuropathy sensory phenotype is characterised by hyposensitivity to applied stimuli that was more marked in the moderate/severe NeuP group than in the mild NeuP or no NeuP groups. Brush-evoked allodynia was present in only those with NeuP (15%); the paradoxical heat sensation did not discriminate between those with (40%) and without (41.3%) NeuP. The “irritable nociceptor” subgroup could only be applied to a minority of patients (6.3%) with NeuP. This study provides a firm basis to rationalise further phenotyping of painful DPN, for instance, stratification of patients with DPN for analgesic drug trials. PMID:27088890
Zunhammer, Matthias; Schweizer, Lauren M; Witte, Vanessa; Harris, Richard E; Bingel, Ulrike; Schmidt-Wilcke, Tobias
2016-10-01
The relationship between glutamate and γ-aminobutyric acid (GABA) levels in the living human brain and pain sensitivity is unknown. Combined glutamine/glutamate (Glx), as well as GABA levels can be measured in vivo with single-voxel proton magnetic resonance spectroscopy. In this cross-sectional study, we aimed at determining whether Glx and/or GABA levels in pain-related brain regions are associated with individual differences in pain sensitivity. Experimental heat, cold, and mechanical pain thresholds were obtained from 39 healthy, drug-free individuals (25 men) according to the quantitative sensory testing protocol and summarized into 1 composite measure of pain sensitivity. The Glx levels were measured using point-resolved spectroscopy at 3 T, within a network of pain-associated brain regions comprising the insula, the anterior cingulate cortex, the mid-cingulate cortex, the dorsolateral prefrontal cortex, and the thalamus. GABA levels were measured using GABA-edited spectroscopy (Mescher-Garwood point-resolved spectroscopy) within the insula, the anterior cingulate cortex, and the mid-cingulate cortex. Glx and/or GABA levels correlated positively across all brain regions. Gender, weekly alcohol consumption, and depressive symptoms were significantly associated with Glx and/or GABA levels. A linear regression analysis including all these factors indicated that Glx levels pooled across pain-related brain regions were positively associated with pain sensitivity, whereas no appreciable relationship with GABA was found. In sum, we show that the levels of the excitatory neurotransmitter glutamate and its precursor glutamine across pain-related brain regions are positively correlated with individual pain sensitivity. Future studies will have to determine whether our findings also apply to clinical populations.
Ezenwa, Miriam O; Yao, Yingwei; Engeland, Christopher G; Molokie, Robert E; Wang, Zaijie Jim; Suarez, Marie L; Wilkie, Diana J
2016-06-01
To test feasibility of a guided audio-visual relaxation intervention protocol for reducing stress and pain in adults with sickle cell disease. Sickle cell pain is inadequately controlled using opioids, necessitating further intervention such as guided relaxation to reduce stress and pain. Attention-control, randomized clinical feasibility pilot study with repeated measures. Randomized to guided relaxation or control groups, all patients recruited between 2013-2014 during clinical visits, completed stress and pain measures via a Galaxy Internet-enabled Android tablet at the Baseline visit (pre/post intervention), 2-week posttest visit and also daily at home between the two visits. Experimental group patients were asked to use a guided relaxation intervention at the Baseline visit and at least once daily for 2 weeks. Control group patients engaged in a recorded sickle cell discussion at the Baseline visit. Data were analysed using linear regression with bootstrapping. At baseline, 27/28 of consented patients completed the study protocol. Group comparison showed that guided relaxation significantly reduced current stress and pain. At the 2-week posttest, 24/27 of patients completed the study, all of whom reported liking the study. Patients completed tablet-based measures on 71% of study days (69% in control group, 72% in experiment group). At the 2-week posttest, the experimental group had significantly lower composite pain index scores, but the two groups did not differ significantly on stress intensity. This study protocol appears feasible. The tablet-based guided relaxation intervention shows promise for reducing sickle cell pain and warrants a larger efficacy trial. The ClinicalTrials.gov Identifier is: NCT02501447. © 2016 John Wiley & Sons Ltd.
Hedaya, Robert
2017-01-01
Context • Five herbs-Urtica dioica (stinging nettle), Boswellia serrata, Equisetum arvense, Allium sativum, and Apium graveolens-have been demonstrated to have activity at several anti-inflammatory pathways and have analgesic properties that are effective in treating chronic musculoskeletal pain. Objectives • The study intended to evaluate the clinical efficacy of a proprietary blend of U dioica, B serrata, E arvense, A sativum, A graveolens, and thiamine (vitamin B1), or "the blend," in the treatment of chronic musculoskeletal pain. Methods • The research team performed a prospective case study. Setting • The study took place at the National Center for Whole Psychiatry in Chevy Chase, MD, USA. Participants were patients who had experienced baseline persistent musculoskeletal pain for at least 4 mo in ≥1 body parts without relief from traditional treatments. Intervention • Participants were provided with a 14-d supply of the study's medication. Two 350-mg capsules were administered 2 ×/d with food. The participants were instructed not to alter or add any therapies for their pain-associated condition for the 14 d of the study. Outcome Measures • The primary outcome measure was the change on a subjectively scored visual analogue scale (VAS), similar to the Western Ontario and McMaster Universities Osteoarthritis Index. The VAS was used to assess pain and the impact of motion and mobility at each location with pain. Each patient was administered the VAS rating scale to assess physical function and pain status at baseline and at the end of 14 d or postintervention. Patients were seen for follow-up at a minimum of 2 wk and underwent an interview, with the VAS rating scale being readministered. Results • A total of 13 patients, involving 27 pain sites, qualified for the study, 5 males and 8 females with a median age of 58 y. The primary sites of pain were (1) the knees-5 sites (18.5%), (2) the shoulders-6 sites (16.6%), and (3) the back (sciatica)-5
Effects of music therapy on labour pain and anxiety in Taiwanese first-time mothers.
Liu, Yu-Hsiang; Chang, Mei-Yueh; Chen, Chung-Hey
2010-04-01
The purpose of the study was to investigate the effects of music on pain reaction and anxiety during labour. Music therapy has been used on clinical medicine. Only few scientific studies validate the value on labour women. Randomised controlled trial. Sixty primiparas expected to have a normal spontaneous delivery were randomly assigned to either the experimental group (n = 30) or the control group (n = 30). The experimental group received routine care and music therapy, whereas the control group received routine care only. A self-report visual analogue scale for pain and a nurse-rated present behavioural intensity were used to measure labour pain. Anxiety was measured with a visual analogue scale for anxiety and finger temperature. Pain and anxiety between groups were compared during the latent phase (2-4 cm cervical dilation) and active phase (5-7 cm) separately. Our results revealed that compared with the control group, the experimental group had significantly lower pain, anxiety and a higher finger temperature during the latent phase of labour. However, no significant differences were found between the two groups on all outcome measures during the active phase. This study provides evidence for the use of music as an empirically based intervention of women for labour pain and anxiety during the latent phase of labour. The findings support that music listening is an acceptable and non-medical coping strategy for labouring women. Especially, apply in reducing the pain and anxiety for women who are at the early phase of labour.
Brown, Christine Ann; Lido, Catherine
2008-05-01
The objectives of the study were to evaluate the possibility of reflexology being used as a non-invasive form of phantom limb pain relief and of empowering patients to maintain any positive results with self-treatment. Prosthetic Services Centre, Herbert Street, Wolverhampton, West Midlands, England. A same-subject, experimental pilot study, recording the intensity of phantom limb pain in weekly pain diaries over a 30-week period, which was divided into five phases: phase 1 gave a baseline of pain, whilst phase 3 was a resting phase. Phases 2, 4 and 5 provided the reflexology interventions. Ten participants with unilateral lower limb amputations and phantom limb pain were selected from the database at the Prosthetic Centre. REFLEXOLOGY INTERVENTIONS: In phase 2, six weekly reflexology treatments were given, which consisted of: full foot reflexology to the remaining foot and full hand reflexology to the hand of the amputated side of the body. In phase 4, six weekly hand reflexology teaching sessions were carried out; patients copied on their own hands what the therapist did on hers. A hand reflexology booklet gave the sequence of the treatment and was used as a reference. In phase 5, the patients self-treated for 6 weeks at home, using the reference material. Over the 30-week period, there was an improvement in the perception of the presence and the intensity of the phantom limb pain, with a corresponding improvement in the duration of the pain and the affect on the person's lifestyle. The improvement was maintained when the clients self-treated. FOLLOW-UP QUESTIONNAIRE: A follow-up questionnaire was carried out in 2007--12 months after the project had ended--to elicit whether the patients had suffered from phantom pain over the previous 12 months, whether they still had relief from phantom limb pain and whether they still self-treated. The project indicated that reflexology treatment, teaching and self-treatment were effective in eradicating or reducing the
Nishijima, Catarine M; Ganev, Ellen G; Mazzardo-Martins, Leidiane; Martins, Daniel F; Rocha, Lúcia R M; Santos, Adair R S; Hiruma-Lima, Clelia A
2014-08-05
Citral (3,7-dimethyl-2,6-octadienal) is an open-chain monoterpenoid present in the essential oils of several medicinal plants. The aim of this work was to evaluate the effects of orally administered citral in experimental models of acute and chronic nociception, inflammation, and gastric ulcers caused by non-steroidal anti-inflammatory drugs (NSAIDs). Oral treatment with citral significantly inhibited the neurogenic and inflammatory pain responses induced by intra-plantar injection of formalin. Citral also had prophylactic and therapeutic anti-nociceptive effects against mechanical hyperalgesia in plantar incision surgery, chronic regional pain syndrome, and partial ligation of sciatic nerve models, without producing any significant motor dysfunction. In addition, citral markedly attenuated the pain response induced by intra-plantar injection of glutamate and phorbol 12-myristate 13-acetate (PMA, a protein kinase C activator), as well as by intrathecal (i.t.) injection of ionotropic and metabotropic glutamate receptor agonists (N-methyl-D-aspartic acid [NMDA] and 1-amino-1,3-dicarboxycyclopentane [trans-ACPD], respectively), substance P, and cytokine tumour necrosis factor-α. However, citral potentiated behaviours indicative of pain caused by i.t., but not intra-plantar, injection of a transient receptor potential vanilloid receptor type 1 (TRPV1) agonist. Finally, the anti-nociceptive action of citral was found to involve significant activation of the 5-HT2A serotonin receptor. The effect of citral was accompanied by a gastro-protective effect against NSAID-induced ulcers. Together, these results show the potential of citral as a new drug for the treatment of pain. Copyright © 2014 Elsevier B.V. All rights reserved.
The effect of cold application on pain due to chest tube removal.
Ertuğ, Nurcan; Ulker, Saadet
2012-03-01
The aim of the research is to determine the effect of cold application on the pain owing to chest tube removal for patients with single pleural chest tube. Removal of chest tubes causes patients to feel pain and interventions used for reducing the pain owing to the removal of chest tubes are not sufficient. Controlled clinical trial with repeated measures. This study was conducted with 140 patients, of whom 70 patients were in the experimental group and 70 patients were in the control group, in a thoracic hospital in Turkey. Data were collected using a data collection form consisting of patients' demographic and health history and Visual Analogue Scale. Cold was applied to patients in the experimental group prior to chest tube removal. In the experimental group, skin temperature and pain intensity was measured for each patient at four time points. In the control group, pain intensity was evaluated for each patient at three time points. Data were evaluated using Chi-square and Repeated Measurements two-way anova tests. The Visual Analogue Scale score was measured immediately after the chest tube removal in the experimental group was 3·85, compared with 5·60 in the control group. There were significant differences on pain with cold application between the two groups prior and after the intervention. Age, gender, the number of days the chest tube was inserted and the chest tube insertion indication had no effect on the pain owing to chest tube removal. Cold application is effective in reducing the pain owing to chest tube removal. Cold application was recommended prior to chest tube removal to reduce the pain owing to removal of chest tube. © 2011 Blackwell Publishing Ltd.
Soares, Anne Danielle Santos; Couceiro, Tânia Cursino de Menezes; Lima, Luciana Cavalcanti; Flores, Fernanda Lobo Lago; Alcoforado, Eusa Maria Belarmino; Filho, Roberto de Oliveira Couceiro
2013-01-01
Vaginal birth delivery may result in acute and persistent perineal pain postpartum. This study evaluated the association between catastrophizing, a phenomenon of poor psychological adjustment to pain leading the individual to magnify the painful experience making it more intense, and the incidence and severity of perineal pain and its relationship to perineal trauma. Cohort study conducted with pregnant women in labor. We used the pain catastrophizing scale during hospitalization and assessed the degree of perineal lesion and pain severity in the first 24 hours and after 8 weeks of delivery using a numerical pain scale. We evaluated 55 women, with acute pain reported by 69.1%, moderate/severe pain by 36.3%, and persistent pain by 14.5%. Catastrophizing mean score was 2.15 ± 1.24. Catastrophizing patients showed a 2.90 relative risk (RR) for perineal pain (95% CI: 1.08-7.75) and RR: 1.31 for developing persistent perineal pain (95% CI: 1.05-1.64). They also showed a RR: 2.2 for developing acute and severe perineal pain (95% CI: 1.11-4.33). The incidence of acute and persistent perineal pain after vaginal delivery is high. Catastrophizing pregnant women are at increased risk for developing acute and persistent perineal pain, as well as severe pain. Perineal trauma increased the risk of persistent perineal pain. Copyright © 2013 Sociedade Brasileira de Anestesiologia. Published by Elsevier Editora Ltda. All rights reserved.
Meisingset, Ingebrigt; Stensdotter, Ann-Katrin; Woodhouse, Astrid; Vasseljen, Ottar
2016-04-01
Neck pain is associated with several alterations in neck motion and motor control, but most of the findings are based on cross-sectional studies. The aim of this study was to investigate associations between changes in neck motion and motor control, and changes in neck pain and disability in physiotherapy patients during a course of treatment. Prospective cohort study. Subjects with non-specific neck pain (n = 71) participated in this study. Neck flexibility, joint position error (JPE), head steadiness, trajectory movement control and postural sway were recorded before commencement of physiotherapy (baseline), at 2 weeks, and at 2 months. Numerical Rating Scale and Neck Disability Index were used to measure neck pain and disability at the day of testing. To analyze within subjects effects in neck motion and motor control, neck pain, and disability over time we used fixed effects linear regression analysis. Changes in neck motion and motor control occurred primarily within 2 weeks. Reduction in neck pain was associated with increased cervical range of motion in flexion-/extension and increased postural sway when standing with eyes open. Decreased neck disability was associated with some variables for neck flexibility and trajectory movement control. Cervical range of motion in flexion-/extension was the only variable associated with changes in both neck pain and neck disability. This study shows that few of the variables for neck motion and motor control were associated with changes neck pain and disability over a course of 2 months with physiotherapy treatment. Copyright © 2015 Elsevier Ltd. All rights reserved.
Zhang, Y; Wang, K; Arendt-Nielsen, L; Cairns, B E
2018-02-01
In burning mouth patients, analgesia after oral administration of clonazepam may result from modulation of peripheral γ-aminobutyric acid (GABA) receptors. The effect of oral administration of test solutions (water, 0.5 mol/L or 0.05 mol/L GABA, 1% lidocaine) was investigated for the amelioration of pain and sensitivity induced by application of capsaicin (1%, 2 min) to the tongue of thirty healthy male and female subjects in this four-session, randomized, placebo-controlled, double-blinded, cross-over study. Intra-oral quantitative sensory testing was used to assess cold (CDT), warm (WDT) and mechanical (MDT) detection thresholds as well as mechanical (MPT) and heat (HPT) pain thresholds. Capsaicin-induced pain intensity was continuously rated on a 0-10 electronic visual analogue scale (VAS). The area under the VAS curve (VASAUC) after rinsing was calculated for each solution. Capsaicin application on the tongue evoked burning pain with a peak of 4.8/10, and significantly increased CDT and MDT while significantly decreasing WDT, HPT, and MPT. The VASAUC was significantly smaller after oral rinse with 0.05 mol/L GABA, 0.5 mol/L GABA, and 1% lidocaine than after oral rinse with water. Rinse with 0.5 mol/L or 0.05 mol/L GABA were similarly effective in decreasing VASAUC. Rinsing with either 1% lidocaine, 0.5 mol/L or 0.05 mol/L GABA also significantly attenuated the effects of capsaicin on WDT and HPT in a treatment independent manner. There were no sex-related differences in these effects of GABA. Capsaicin-induced burning tongue pain and decreases in WDT and HPT can be ameliorated by rinsing the mouth with lidocaine and GABA solutions. Rinsing the mouth with an oral GABA containing solution ameliorated burning pain and increased heat sensitivity produced by application of capsaicin to the tongue. This finding suggests that GABA can act as a local analgesic agent in the oral cavity. © 2017 European Pain Federation - EFIC®.
Pain assessment in animal models of osteoarthritis.
Piel, Margaret J; Kroin, Jeffrey S; van Wijnen, Andre J; Kc, Ranjan; Im, Hee-Jeong
2014-03-10
Assessment of pain in animal models of osteoarthritis is integral to interpretation of a model's utility in representing the clinical condition, and enabling accurate translational medicine. Here we describe behavioral pain assessments available for small and large experimental osteoarthritic pain animal models. Copyright © 2013 Elsevier B.V. All rights reserved.
Zgierska, Aleksandra E; Burzinski, Cindy A; Cox, Jennifer; Kloke, John; Stegner, Aaron; Cook, Dane B; Singles, Janice; Mirgain, Shilagh; Coe, Christopher L; Bačkonja, Miroslav
2016-10-01
To assess benefits of mindfulness meditation and cognitive behavioral therapy (CBT)-based intervention for opioid-treated chronic low back pain (CLBP). 26-week parallel-arm pilot randomized controlled trial (Intervention and Usual Care versus Usual Care alone). Outpatient. Adults with CLBP, prescribed ≥30 mg/day of morphine-equivalent dose (MED) for at least 3 months. The intervention comprised eight weekly group sessions (meditation and CLBP-specific CBT components) and 30 minutes/day, 6 days/week of at-home practice. Outcome measures were collected at baseline, 8, and 26 weeks: primary-pain severity (Brief Pain Inventory) and function/disability (Oswestry Disability Index); secondary-pain acceptance, opioid dose, pain sensitivity to thermal stimuli, and serum pain-sensitive biomarkers (Interferon-γ; Tumor Necrosis Factor-α; Interleukins 1ß and 6; C-reactive Protein). Thirty-five (21 experimental, 14 control) participants were enrolled and completed the study. They were 51.8 ± 9.7 years old, 80% female, with severe CLBP-related disability (66.7 ± 11.4), moderate pain severity (5.8 ± 1.4), and taking 148.3 ± 129.2 mg/day of MED. Results of the intention-to-treat analysis showed that, compared with controls, the meditation-CBT group reduced pain severity ratings during the study (P = 0.045), with between-group difference in score change reaching 1 point at 26 weeks (95% Confidence Interval: 0.2,1.9; Cohen's d = 0.86), and decreased pain sensitivity to thermal stimuli (P < 0.05), without adverse events. Exploratory analyses suggested a relationship between the extent of meditation practice and the magnitude of intervention benefits. Meditation-CBT intervention reduced pain severity and sensitivity to experimental thermal pain stimuli in patients with opioid-treated CLBP. © 2016 American Academy of Pain Medicine. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.
Pain education to prevent chronic low back pain: a study protocol for a randomised controlled trial
Traeger, Adrian C; Moseley, G Lorimer; Hübscher, Markus; Lee, Hopin; Skinner, Ian W; Nicholas, Michael K; Henschke, Nicholas; Refshauge, Kathryn M; Blyth, Fiona M; Main, Chris J; Hush, Julia M; Pearce, Garry; McAuley, James H
2014-01-01
Introduction Low back pain (LBP) is the leading cause of disability worldwide. Of those patients who present to primary care with acute LBP, 40% continue to report symptoms 3 months later and develop chronic LBP. Although it is possible to identify these patients early, effective interventions to improve their outcomes are not available. This double-blind (participant/outcome assessor) randomised controlled trial will investigate the efficacy of a brief educational approach to prevent chronic LBP in ‘at-risk’ individuals. Methods/analysis Participants will be recruited from primary care practices in the Sydney metropolitan area. To be eligible for inclusion participants will be aged 18–75 years, with acute LBP (<4 weeks’ duration) preceded by at least a 1 month pain-free period and at-risk of developing chronic LBP. Potential participants with chronic spinal pain and those with suspected serious spinal pathology will be excluded. Eligible participants who agree to take part will be randomly allocated to receive 2×1 h sessions of pain biology education or 2×1 h sessions of sham education from a specially trained study physiotherapist. The study requires 101 participants per group to detect a 1-point difference in pain intensity 3 months after pain onset. Secondary outcomes include the incidence of chronic LBP, disability, pain intensity, depression, healthcare utilisation, pain attitudes and beliefs, global recovery and recurrence and are measured at 1 week post-intervention, and at 3, 6 and 12 months post LBP onset. Ethics/dissemination Ethical approval was obtained from the University of New South Wales Human Ethics Committee in June 2013 (ref number HC12664). Outcomes will be disseminated through publication in peer-reviewed journals and presentations at international conference meetings. Trial registration number https://www.anzctr.org.au/Trial/Registration/TrialReview.aspx?ACTRN=12612001180808 PMID:24889854
George, Steven Z; Wittmer, Virgil T; Fillingim, Roger B; Robinson, Michael E
2006-03-01
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. 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. 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. 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. This study supported the neuromatrix theory of pain for patients with CLBP, as cognitive
Miller, Jordan; MacDermid, Joy C; Walton, David M; Richardson, Julie
2015-10-14
Previous research suggests that self-management programs for people with chronic pain improve knowledge and self-efficacy but result in negligible effects on function. This study will investigate the effectiveness self-management support with pain science education and exercise on improving function for people with chronic pain in comparison to a wait-list control. A secondary objective is to determine which variables help to predict response to the intervention. This study will be an unblinded, randomized controlled trial with 110 participants comparing a 6-week program that includes self-management support, pain science education and exercise to a wait-list control. The primary outcome will be function measured by the Short Musculoskeletal Function Assessment - Dysfunction Index. Secondary outcomes will include pain intensity measured by a numeric pain rating scale, pain interference measured by the eight-item PROMIS pain interference item-bank, how much patients are bothered by functional problems measured by the Short Musculoskeletal Function Assessment - Bother Index, catastrophic thinking measured by the Pain Catastrophizing Scale, fear of movement/re-injury measured by the 11-item Tampa Scale of Kinesiophobia, sense of perceived injustice measured by the Injustice Experience Questionnaire, self-efficacy measured by the Pain Self-Efficacy Questionnaire, pain sensitivity measured by pressure pain threshold and cold sensitivity testing, fatigue measured by a numeric fatigue rating scale, pain neurophysiology knowledge measured by the Neurophysiology of Pain Questionnaire, healthcare utilization measured by number of visits to a healthcare provider, and work status. Assessments will be completed at baseline, 7 and 18 weeks. After the 18-week assessment, the groups will crossover; however, we anticipate carry-over effects with the treatment. Therefore, data from after the crossover will be used to estimate within-group changes and to determine predictors of
Palmgren, Per J; Andreasson, Daniel; Eriksson, Magnus; Hägglund, Andreas
2009-06-30
Although cervical pain is widespread, most victims are only mildly and occasionally affected. A minority, however, suffer chronic pain and/or functional impairments. Although there is abundant literature regarding nontraumatic neck pain, little focuses on diagnostic criteria. During the last decade, research on neck pain has been designed to evaluate underlying pathophysiological mechanisms, without noteworthy success. Independent researchers have investigated postural balance and cervicocephalic kinesthetic sensibility among patients with chronic neck pain, and have (in most cases) concluded the source of the problem is a reduced ability in the neck's proprioceptive system. Here, we investigated cervicocephalic kinesthetic sensibility and postural balance among patients with nontraumatic chronic neck pain. Ours was a two-group, observational pilot study of patients with complaints of continuous neck pain during the 3 months prior to recruitment. Thirteen patients with chronic neck pain of nontraumatic origin were recruited from an institutional outpatient clinic. Sixteen healthy persons were recruited as a control group. Cervicocephalic kinesthetic sensibility was assessed by exploring head repositioning accuracy and postural balance was measured with computerized static posturography. Parameters of cervicocephalic kinesthetic sensibility were not reduced. However, in one of six test movements (flexion), global repositioning errors were significantly larger in the experimental group than in the control group (p < .05). Measurements did not demonstrate any general impaired postural balance, and varied substantially among participants in both groups. In patients with nontraumatic chronic neck pain, we found statistically significant global repositioning errors in only one of six test movements. In this cohort, we found no evidence of impaired postural balance.Head repositioning accuracy and computerized static posturography are imperfect measures of functional
Translational neuropathic pain research: A clinical perspective.
Bouhassira, D; Attal, N
2016-12-03
Neuropathic pain encompasses a broad range of conditions associated with a lesion or disease of the peripheral or central somatosensory system and its prevalence in the general population may be as high as 7-8%. The interest in the pathophysiology of neuropathic pain has increased over the last two decades with an exponential increase in the number of experimental studies. However, despite the hopes raised by scientific discoveries, there has been no rational development of a truly new class of drugs. This situation revealing the limitations of certain experimental models, also results of limitations in clinical research. One of the reasons for the therapeutic difficulties in these patients is probably due to the fact that treatments are used in a uniform fashion whatever the clinical picture, while these syndromes are in fact highly heterogeneous. Clinical advances have recently been made in this field, following the validation of new specific clinical tools and the standardization of quantitative sensory testing paradigms facilitating improvements in the clinical characterization of these syndromes. It has been clearly demonstrated that neuropathic pain is a consistent clinical entity, but it is multidimensional in terms of its clinical expression, with different sensory profiles, potentially reflecting specific pathophysiological mechanisms. This new conceptualization of neuropathic pain should improve the characterization of the responder profiles in clinical trials and provide valuable information for the development of new and more clinically sound translational approaches in experimental models in animals. Copyright © 2016. Published by Elsevier Ltd.
Zhong, Guangjun; Liang, Zhu; Kan, Jiang; Muheremu, Aikeremujiang
2018-01-01
Objective This study was performed to determine the efficacy of selective peripheral nerve resection for treatment of persistent neuropathic pain after total knee arthroplasty (TKA). Methods Patients who underwent TKA in our department from January 2013 to July 2016 and experienced persistent pain around the knee joint after TKA were retrospectively included in the current study. Sixty patients were divided into experimental and control groups according the treatment they received. The treatment effect was evaluated by the Hospital for Special Surgery (HSS) knee score and visual analog scale (VAS) pain score preoperatively and at 1, 2, 3, 6, and 12 months postoperatively. Results The HSS knee scores were higher in both groups after than before the treatment, and HSS knee scores were significantly higher in the experimental group than in the control group. The VAS pain scores were lower in both groups after than before the treatment, and VAS pain scores were significantly lower in the experimental group than in the control group. Conclusions Selective peripheral nerve resection is an effective treatment method for persistent neuropathic pain after TKA.
Singh, Jasvinder A; Noorbaloochi, Siamak; Knutson, Keith L
2017-01-14
There are few studies with an assessment of the levels of cytokines or neuropeptides as correlates of pain and pain relief in patients with painful joint diseases. Our objective was to assess whether improvements from baseline to 2-months in serum cytokine, chemokine and substance P levels were associated with clinically meaningful pain relief at 2-months post-injection in patients with painful total knee arthroplasty (TKA). Using data from randomized trial of 60 TKAs, we assessed the association of change in cytokine/chemokine/Substance P levels with primary study outcome, clinically important improvement in Western Ontario McMaster Osteoarthritis Index (WOMAC) pain subscale at 2-months post-injection using Student's t-tests and Spearman's correlation coefficient (non-parametric). Patients were categorized as pain responders (20-point reduction or more on 0-100 WOMAC pain) vs. pain non-responders. Sensitivity analysis used 0-10 daytime pain numeric rating scale (NRS) instead of WOMAC pain subscale. In a pilot study, compared to non-responders (n = 23) on WOMAC pain scale at 2-months, pain responders (n = 12) had significantly greater increase in serum levels of IL-7, IL-10, IL-12, eotaxin, interferon gamma and TNF-α from baseline to 2-months post-injection (p < 0.05 for all). Change in several cytokine/chemokine and substance P levels from pre-injection to 2-month follow-up correlated significantly with change in WOMAC pain with correlation coefficients ranging -0.37 to -0.51: IL-2, IL-7, IL-8, IL-9, IL-16, IL-12p, GCSF, IFN gamma, IP-10, MCP, MIP1b, TNF-α and VEGF (n = 35). Sensitivity analysis showed that substance P decreased significantly more from baseline to 2-months in the pain responders (0.54 ± 0.53; n = 10) than in the pain non-responders (0.48 ± 1.18; n = 9; p = 0.023) and that this change in serum substance P correlated significantly with change in daytime NRS pain, correlation coefficient was 0.53 (p = 0
Buchbinder, R; Jolley, D; Wyatt, M
2001-12-01
Quasi-experimental, nonrandomized, nonequivalent, parallel group-controlled study involving before and after telephone surveys of the general population and postal surveys of general practitioners was conducted, with an adjacent state used as a control group. To evaluate the effectiveness of a population-based intervention designed to alter beliefs about back pain, influence medical management, and reduce disability and workers' compensation-related costs. A multimedia campaign begun during 1997 in Victoria, Australia, positively advised patients with back pain to stay active and exercise, not to rest for prolonged periods, and to remain at work. The campaign's impact on population beliefs about back pain and fear-avoidance beliefs was measured in telephone surveys, and the effect of the campaign on the potential management of low back pain by general practitioners was assessed by eliciting their likely approach to two hypothetical scenarios in mailed surveys. Demographically identical population groups in Victoria and the control state, New South Wales, were surveyed at three times: before, during, and after intervention in Victoria. The studies were completed by 4730 individuals in the general population and 2556 general practitioners. There were large statistically significant improvements in back pain beliefs over time in Victoria (mean scores on the Back Beliefs Questionnaire, 26.5, 28.4, and 29.7), but not in New South Wales (26.3, 26.2, and 26.3, respectively). Among those who reported back pain during the previous year, fear-avoidance beliefs about physical activity improved significantly in Victoria (mean scores on the Fear-Avoidance Beliefs Questionnaire for physical activity, 14, 12.5, and 11.6), but not in New South Wales (13.3, 13.6, and 12.7, respectively). General practitioners in Victoria reported significant improvements over time in beliefs about back pain management, as compared with their interstate colleagues. There were statistically
[Pain in Spanish rheumatology outpatient offices: EPIDOR epidemiological study].
Gamero Ruiz, F; Gabriel Sánchez, R; Carbonell Abello, J; Tornero Molina, J; Sánchez-Magro, I
2005-04-01
To establish the prevalence and characteristics of rheumatologic pain in Spanish adult population cared in specialized rheumatology offices. Cross selection study in a population of patients cared in rheumatology offices of public Spanish hospitals. 1,134 patients selected through random sampling based on waiting lists of patients, during a period of 1 week, in rheumatology offices of each participating hospital. MAIN OUTCOMES OF THE STUDY: Reason behind the consultation (a new patient [NP] or a patient for revision [RP]), characteristics of the patient (sex, age, habits [alcohol/tobacco], marital status), location, type, intensity, duration, tolerance and management of pain; treatment (pharmacological or non-pharmacological) carried out; satisfaction with the treatment; and association with fibromyalgia. The prevalence of pain in NP was 98.6% and in RP 95.1%, with a global prevalence of 96%, predominating mainly in adult sedentary women with fibromyalgia. The frequency of acute pain was 20.9% and this of chronic pain 79.1% [corrected] The prevalence of fibromyalgia was 12% (2.2% in men, and 15.5% in women). The most prevalent pattern of current dominant pain was this of the mechanical type. More frequent associated pathologies were: hypertension (21.7%), depression (14.4%), gastrointestinal diseases (13.8%) and anxiety (13.4%). All variables analyzed in the study showed changes according to age, sex, and type of patient (NP or RP). Most used treatment was pharmacological; more than 57.6% of patients were receiving NSAIDs. In NP, medical prescriber of the treatment was first the general practitioner (56.1%) followed by the rheumatologist (14.1%); in PR the first one was the rheumatologist (69.9%) followed by the general practitioner (16.5%). Our results show that the prevalence of the rheumatologic pain is very high, predominating mainly in adult women with fibromyalgia. Pain location, intensity, and type, associated pathology, and treatment vary according to age
SuperPain--a resource on pain-relieving compounds targeting ion channels.
Gohlke, Björn O; Preissner, Robert; Preissner, Saskia
2014-01-01
Pain is more than an unpleasant sensory experience associated with actual or potential tissue damage: it is the most common reason for physician consultation and often dramatically affects quality of life. The management of pain is often difficult and new targets are required for more effective and specific treatment. SuperPain (http://bioinformatics.charite.de/superpain/) is freely available database for pain-stimulating and pain-relieving compounds, which bind or potentially bind to ion channels that are involved in the transmission of pain signals to the central nervous system, such as TRPV1, TRPM8, TRPA1, TREK1, TRESK, hERG, ASIC, P2X and voltage-gated sodium channels. The database consists of ∼8700 ligands, which are characterized by experimentally measured binding affinities. Additionally, 100 000 putative ligands are included. Moreover, the database provides 3D structures of receptors and predicted ligand-binding poses. These binding poses and a structural classification scheme provide hints for the design of new analgesic compounds. A user-friendly graphical interface allows similarity searching, visualization of ligands docked into the receptor, etc.
Lai, H. Henry; Jemielita, Thomas; Sutcliffe, Siobhan; Bradley, Catherine S.; Naliboff, Bruce; Williams, David A.; Gereau, Robert W.; Kreder, Karl; Clemens, J. Quentin; Rodriguez, Larissa V.; Krieger, John N.; Farrar, John T.; Robinson, Nancy; Landis, J. Richard
2017-01-01
Purpose We characterized the location and spatial distribution of whole body pain among patients with urologic chronic pelvic pain syndrome (UCPPS) using a body map; and compared the severity of urinary symptoms, pelvic pain, non-pelvic pain, and psychosocial health among patients with different pain patterns. Methods 233 women and 191 men with UCPPS enrolled in a multi-center, one-year observational study completed a battery of baseline measures, including a body map describing the location of pain during the past week. Participants were categorized as having “pelvic pain only” if they reported pain in the abdomen and pelvis only. Participants who reported pain beyond the pelvis were further divided into two sub-groups based on the number of broader body regions affected by pain: an “intermediate” group (1–2 additional regions outside the pelvis) and a “widespread pain” group (3–7 additional regions). Results Of the 424 enrolled patients 25% reported pelvic pain only, and 75% reported pain beyond the pelvis of which 38% reported widespread pain. Participants with greater number of pain locations had greater non-pelvic pain severity (p<0.0001), sleep disturbance (p=0.035), depression (p=0.005), anxiety (p=0.011), psychological stress (p=0.005), negative affect scores (p=0.0004), and worse quality of life (p≤0.021). No difference in pelvic pain and urinary symptom severity were observed by increasing pain distribution. Conclusions Three-quarters of men and women with UCPPS reported pain outside the pelvis. Widespread pain was associated with greater severity of non-pelvic pain symptoms, poorer psychosocial health and worse quality of life, but not worse pelvic pain or urinary symptoms. PMID:28373134
Effect of near-infrared rays on female menstrual pain in Korea.
Lee, Jin-Min; Kim, Kye-Ha
2017-09-01
Most Korean women who experience menstrual pain have reported taking pain medicine and making use of complementary alternative therapies. However, because some interventions may cause side effects, more effective pain-relieving measures need to be identified. This study using a non-equivalent group design, evaluated the effects of near-infrared rays on dysmenorrhea among Korean women. The experimental group wore a near-infrared ray abdominal belt for the duration of one menstrual cycle until the end of the menstrual period, while the control group used hot packs. The level of menstrual pain, menstrual pain duration, and pain medicine use were measured. The menstrual pain, average menstrual pain duration, and use of analgesics were reduced in the near-infrared rays group. The results of this study indicate that the near-infrared ray LED belt was effective in reducing menstrual pain, menstrual pain duration compared to the use of analgesics in Korean women with dysmenorrhea. Therefore, near-infrared rays may be used to relieve menstrual pain and improve the quality of life of women with dysmenorrhea in Korea. © 2017 John Wiley & Sons Australia, Ltd.
Rhudy, Jamie L; Martin, Satin L; Terry, Ellen L; Delventura, Jennifer L; Kerr, Kara L; Palit, Shreela
2012-11-01
Emotion can modulate pain and spinal nociception, and correlational data suggest that cognitive-emotional processes can facilitate wind-up-like phenomena (ie, temporal summation of pain). However, there have been no experimental studies that manipulated emotion to determine whether within-subject changes in emotion influence temporal summation of pain (TS-pain) and the nociceptive flexion reflex (TS-NFR, a physiological measure of spinal nociception). The present study presented a series of emotionally charged pictures (mutilation, neutral, erotic) during which electric stimuli at 2 Hz were delivered to the sural nerve to evoke TS-pain and TS-NFR. Participants (n=46 healthy; 32 female) were asked to rate their emotional reactions to pictures as a manipulation check. Pain outcomes were analyzed using statistically powerful multilevel growth curve models. Results indicated that emotional state was effectively manipulated. Further, emotion modulated the overall level of pain and NFR; pain and NFR were highest during mutilation and lowest during erotic pictures. Although pain and NFR both summated in response to the 2-Hz stimulation series, the magnitude of pain summation (TS-pain) and NFR summation (TS-NFR) was not modulated by picture-viewing. These results imply that, at least in healthy humans, within-subject changes in emotions do not promote central sensitization via amplification of temporal summation. However, future studies are needed to determine whether these findings generalize to clinical populations (eg, chronic pain). Copyright © 2012 International Association for the Study of Pain. Published by Elsevier B.V. All rights reserved.
McGregor, CIndy; Boyles, Robert; Murahashi, Laura; Sena, Tanya; Yarnall, Robert
2014-11-01
Posterior-to-anterior (PA) vertebral mobilization to the thoracic spine has been studied as an intervention for neck pain. Our purpose was to explore effects of a different mobilization technique, transverse vertebral pressure, on cervical range of motion (ROM) and pain when applied to the thoracic spine among participants with neck pain. A single-blinded quasi-experimental study with a one-group pretest-posttest design. A transverse group consisted of 21 participants whose neck pain increased with active movements. A non-intervention group of 20 asymptomatic participants was included simply to ensure rater blinding. The treatment group received Grades IV to IV+ transverse mobilizations at T1 through T4 bilaterally. Measurements taken immediately after intervention included pre/post cervical ROM, distant pressure pain threshold (PPT), and a numerical pain rating scale (NPRS). Analysis utilized t-tests and ordinal counterparts. The transverse group demonstrated significant gains in extension and bilateral rotation (P≤0.005) but not flexion or side-bend. A total of 57% of mobilized participants reported clinically meaningful decreased pain (P<0.001). Seven participants exceeded the PPT MDC95 of 0.36 kg/cm(2). The non-intervention group had no significant changes in ROM or NPRS scores. After 8 minutes of transverse mobilization to the upper thoracic spine, significant gains in cervical extension and bilateral rotation, and decreased pain scores were found. There were no adverse effects. Unlike other mobilization studies, PPT changes at a remote site were statistically but not clinically meaningful. Findings suggest that transverse mobilization would be a productive topic for controlled clinical trials.
Chronic pain among community-dwelling elderly: a population-based clinical study.
Rapo-Pylkkö, Susanna; Haanpää, Maija; Liira, Helena
2016-06-01
To present the occurrence, characteristics, etiology, interference, and medication of chronic pain among the elderly living independently at home. A total of 460 subjects in three cohorts aged 75, 80 and 85 years respectively received visits by communal home-care department nurses for a cross-sectional survey. Of them, 175 had chronic (duration ≥ 3 months) pain with an average intensity of ≥ 4/10 and/or ≥ moderate interference in daily life. Clinical assessment was performed for consenting subjects to define the location, intensity, etiology, type, interference and medications of chronic pain. According to home visits, elderly people with chronic pain rated their health and mobility worse and felt sadder, lonelier and more tired than those without chronic pain. A geriatrician made clinical assessments for 106 patients with chronic pain in 2009-2013. Of them, 66 had three, 35 had two and 5 had one pain condition. The worst pain was musculoskeletal in 88 (83%) of patients. Pain was pure nociceptive in 61 (58%), pure neuropathic in 9 (8%), combined nociceptive and neuropathic pain in 34 (32%), and idiopathic in 2 (2%) patients. On a numerical rating scale from 0 to 10, the mean and maximal intensity of the worst pain was 5.7 and 7.7, respectively, while the mean pain interference was 5.9. Mean pain intensity and maximal pain intensity decreased by age. Duration of pain was longer than 5 years in 51 (48%) patients. Regular pain medication was used by 82 (77%) patients, most commonly paracetamol or NSAIDs. Although pain limited the lives of the elderly with chronic pain, they were as satisfied with their lives as those without chronic pain. Elderly people in our study often suffered from chronic pain, mostly musculoskeletal pain, and the origin of pain was neuropathic in up to 40% of these cases. However, elderly people with chronic pain rarely used the medications specifically for neuropathic pain. Based on increased loneliness, sadness and tiredness, as well as
Association of hip pain with radiographic evidence of hip osteoarthritis: diagnostic test study
Nevitt, Michael C; Niu, Jingbo; Clancy, Mary M; Lane, Nancy E; Link, Thomas M; Vlad, Steven; Tolstykh, Irina; Jungmann, Pia M.; Felson, David T; Guermazi, Ali
2015-01-01
Study question Is there concordance between hip pain and radiographic hip osteoarthritis? Methods In this diagnostic test study, pelvic radiographs were assessed for hip osteoarthritis in two cohorts: the Framingham Osteoarthritis Study (community of Framingham, Massachusetts) and the Osteoarthritis Initiative (a multicenter longitudinal cohort study of osteoarthritis in the United States). Using visual representation of the hip joint, participants reported whether they had hip pain on most days and the location of the pain: anterior, groin, lateral, buttocks, or low back. In the Framingham study, participants with hip pain were also examined for hip pain with internal rotation. The authors analysed the agreement between radiographic hip osteoarthritis and hip pain, and for those with hip pain suggestive of hip osteoarthritis they calculated the sensitivity, specificity, positive predictive value, and negative predictive value of radiographs as the diagnostic test. Study answer and limitations In the Framingham study (n=946), only 15.6% of hips in patients with frequent hip pain showed radiographic evidence of hip osteoarthritis, and 20.7% of hips with radiographic hip osteoarthritis were frequently painful. The sensitivity of radiographic hip osteoarthritis for hip pain localised to the groin was 36.7%, specificity 90.5%, positive predictive value 6.0%, and negative predictive value 98.9%. Results did not differ much for hip pain at other locations or for painful internal rotation. In the Osteoarthritis Initiative study (n=4366), only 9.1% of hips in patients with frequent pain showed radiographic hip osteoarthritis, and 23.8% of hips with radiographic hip osteoarthritis were frequently painful. The sensitivity of definite radiographic hip osteoarthritis for hip pain localised to the groin was 16.5%, specificity 94.0%, positive predictive value 7.1%, and negative predictive value 97.6%. Results also did not differ much for hip pain at other locations. What this
Lai, H. Henry; Krieger, John N.; Pontari, Michel A.; Buchwald, Dedra; Hou, Xiaoling; Landis, J. Richard
2015-01-01
Purpose To describe bladder-associated symptoms in patients with urologic chronic pelvic pain syndromes (UCPPS) and to correlate these symptoms with urologic, non-urologic, psychosocial, and quality of life measures. Methods Participants were 233 women and 191 men with interstitial cystitis/bladder pain syndrome or chronic prostatitis/chronic pelvic pain syndrome in a multi-center study. They completed a battery of measures, including items asking if their pain worsened with bladder filling (“painful filling”) or if their urge to urinate was due to pain, pressure, or discomfort (“painful urgency”). Participants were categorized into 3 groups: 1) “both” painful filling and painful urgency, 2) “either” painful filling or painful urgency, or 3) “neither.” Results Seventy-five percent of men and 88% of women were categorized as “both” or “either.” These bladder characteristics were associated with more severe urologic symptoms (increased pain, frequency, urgency), higher somatic symptom burden, depression, and worse quality of life (all p<0.01, 3-group trend test). A gradient effect was observed across groups (both > either > neither). Compared to those in the “neither” group, men categorized as “both” or “either” reported more frequent UCPPS symptom flares, catastrophizing, and irritable bowel syndrome, and women categorized as “both” or “either” were more likely to have negative affect and chronic fatigue syndrome. Conclusions Men and women with bladder symptoms characterized as painful filling or painful urgency had more severe urologic symptoms, more generalized symptoms, and worse quality of life than participants who reported neither characteristic, suggesting that these symptom characteristics might represent important subsets of UCPPS patients. PMID:26192257
The Impact of Social Isolation on Pain Interference: A Longitudinal Study.
Karayannis, Nicholas V; Baumann, Isabel; Sturgeon, John A; Melloh, Markus; Mackey, Sean C
2018-04-12
Evidence suggests social interactions play an important role in pain perception. The aim of this study was to determine whether social isolation (SI) in people with persistent pain determines pain interference (PI) and physical function over time. Patients seeking care at a tertiary pain management referral center were administered the Patient Reported Outcome Measurement Information System (PROMIS®) SI, PI, physical function, depression, and average pain intensity item banks at their initial consultation and subsequent visits as part of their routine clinical care. We used a post hoc simulation of an experiment using propensity score matching (n = 4,950) and carried out a cross-lagged longitudinal analysis (n = 312) of retrospective observational data. Cross-lagged longitudinal analysis showed that SI predicted PI at the next time point, above and beyond the effects of pain intensity and covariates, but not vice versa. These data support the importance of SI as a factor in pain-related appraisal and coping and demonstrate that a comprehensive assessment of the individuals' social context can provide a better understanding of the differential trajectories for a person living with pain. Our study provides evidence that the impact of pain is reduced in individuals who perceive a greater sense of inclusion from and engagement with others. This study enhances the understanding of how social factors affect pain and have implications for how the effectiveness of therapeutic interventions may be improved. Therapeutic interventions aimed at increasing social connection hold merit in reducing the impact of pain on engagement with activities.
Social laughter is correlated with an elevated pain threshold
Dunbar, R. I. M.; Baron, Rebecca; Frangou, Anna; Pearce, Eiluned; van Leeuwen, Edwin J. C.; Stow, Julie; Partridge, Giselle; MacDonald, Ian; Barra, Vincent; van Vugt, Mark
2012-01-01
Although laughter forms an important part of human non-verbal communication, it has received rather less attention than it deserves in both the experimental and the observational literatures. Relaxed social (Duchenne) laughter is associated with feelings of wellbeing and heightened affect, a proximate explanation for which might be the release of endorphins. We tested this hypothesis in a series of six experimental studies in both the laboratory (watching videos) and naturalistic contexts (watching stage performances), using change in pain threshold as an assay for endorphin release. The results show that pain thresholds are significantly higher after laughter than in the control condition. This pain-tolerance effect is due to laughter itself and not simply due to a change in positive affect. We suggest that laughter, through an endorphin-mediated opiate effect, may play a crucial role in social bonding. PMID:21920973
Social laughter is correlated with an elevated pain threshold.
Dunbar, R I M; Baron, Rebecca; Frangou, Anna; Pearce, Eiluned; van Leeuwen, Edwin J C; Stow, Julie; Partridge, Giselle; MacDonald, Ian; Barra, Vincent; van Vugt, Mark
2012-03-22
Although laughter forms an important part of human non-verbal communication, it has received rather less attention than it deserves in both the experimental and the observational literatures. Relaxed social (Duchenne) laughter is associated with feelings of wellbeing and heightened affect, a proximate explanation for which might be the release of endorphins. We tested this hypothesis in a series of six experimental studies in both the laboratory (watching videos) and naturalistic contexts (watching stage performances), using change in pain threshold as an assay for endorphin release. The results show that pain thresholds are significantly higher after laughter than in the control condition. This pain-tolerance effect is due to laughter itself and not simply due to a change in positive affect. We suggest that laughter, through an endorphin-mediated opiate effect, may play a crucial role in social bonding.
Wan, Dawn Wong Lit; Arendt-Nielsen, Lars; Wang, Kelun; Xue, Charlie Changli; Wang, Yanyi; Zheng, Zhen
2018-03-27
Healthy humans can be divided into the pain adaptive (PA) and the pain nonadaptive (PNA) groups; PA showed a greater decrease in pain rating to a cold pressor test (CPT) than PNA. This study examined if the dichotomy of pain adaptability existed in individuals with chronic musculoskeletal pain. CPTs at 2°C and 7°C were used to assess the status of pain adaptability in participants with either chronic nonspecific low back pain or knee osteoarthritis. The participants' potency of conditioned pain modulation (CPM) and local inhibition were measured. The strengths of pain adaptability at both CPTs were highly correlated. PA and PNA did not differ in their demographic characteristics, pain thresholds from thermal and pressure stimuli, or potency of local inhibition or CPM. PA reached their maximum pain faster than PNA (t 41 = -2.76, P < .01), and had a gradual reduction of pain unpleasantness over 7 days whereas PNA did not (F 6,246 = 3.01, P = .01). The dichotomy of pain adaptability exists in musculoskeletal pain patients. Consistent with the healthy human study, the strength of pain adaptability and potency of CPM are not related. Pain adaptability could be another form of endogenous pain inhibition of which clinical implication is yet to be understood. The dichotomy of pain adaptability was identified in healthy humans. The current study confirms that this dichotomy also exists in individuals with chronic musculoskeletal pain, and could be reliably assessed with CPTs at 2°C and 7°C. Similar to the healthy human study, pain adaptability is not associated with CPM, and may reflect the temporal aspect of pain inhibition. Copyright © 2018 The American Pain Society. Published by Elsevier Inc. All rights reserved.
Parents’ Management of Children’s Pain at Home after Surgery
Vincent, Catherine; Chiappetta, Maria; Beach, Abigail; Kiolbasa, Carolyn; Latta, Kelsey; Maloney, Rebekah; Van Roeyen, Linda Sue
2012-01-01
Purpose We tested Home Pain Management for Children (HPMC) for effects on pain intensity, analgesics administered, satisfaction, and use of healthcare services over 3 post-discharge days. Design and Methods In this quasi-experimental study with 108 children and their parents, we used the numeric rating scale (NRS) or the Faces Pain Scale-Revised (FPS-R), calculated percentages of analgesics administered, and asked questions about expectations, satisfaction, and services. Between-group differences were tested with t-tests and ANOVA. Results After HPMC, children reported moderate pain and parents administered more analgesics on 2 study days. Parents and children were satisfied; parents used few services. Written instructions and a brief interactive session were not sufficient to change parents’ analgesic administration practices to relieve their children’s pain. Practice Implications Further research is needed to develop and test effective education interventions to facilitate relief of children’s post-operative pain. PMID:22463471
Pain, frailty and comorbidity on older men: the CHAMP study.
Blyth, Fiona M; Rochat, Stephane; Cumming, Robert G; Creasey, Helen; Handelsman, David J; Le Couteur, David G; Naganathan, Vasi; Sambrook, Philip N; Seibel, Markus J; Waite, Louise M
2008-11-15
Intrusive pain is likely to have a serious impact on older people with limited ability to respond to additional stressors. Frailty is conceptualised as a functional and biological pattern of decline accumulating across multiple physiological systems, resulting in a decreased capacity to respond to additional stressors. We explored the relationship between intrusive pain, frailty and comorbid burden in 1705 community-dwelling men aged 70 or more who participated in the baseline phase of the CHAMP study, a large epidemiological study of healthy ageing based in Sydney, Australia. 9.4% of men in the study were frail (according to the commonly-used Cardiovascular Health Study frailty criteria).Using a combination of self-report and clinical measures, we found an association between frailty and intrusive pain that remained after accounting for demographic characteristics, number of comorbidities, self-reported depressed mood and arthritis (adjusted odds ratio 1.7 (95% confidence interval (CI) 1.1-2.7), p=0.0149). The finding that adjusting for depressed mood, but not a history of arthritis, attenuated the relationship between frailty and intrusive pain points to a key role for central mechanisms. Additionally, men with the highest overall health burden (frail plus high comorbid burden) were most likely to report intrusive pain (adjusted odds ratio 3.0 (95% CI 1.6-5.5), p=0.0004). These findings provide support for the concept that intrusive pain is an important challenge for older men with limited capacity to respond to additional physical stressors. To our knowledge, this is the first study to explore specifically the relationship between pain and frailty.
Burzinski, Cindy A.; Cox, Jennifer; Kloke, John; Stegner, Aaron; Cook, Dane B.; Singles, Janice; Mirgain, Shilagh; Coe, Christopher L.; Bačkonja, Miroslav
2016-01-01
Objective. To assess benefits of mindfulness meditation and cognitive behavioral therapy (CBT)-based intervention for opioid-treated chronic low back pain (CLBP). Design. 26-week parallel-arm pilot randomized controlled trial (Intervention and Usual Care versus Usual Care alone). Setting. Outpatient. Subjects. Adults with CLBP, prescribed ≥30 mg/day of morphine-equivalent dose (MED) for at least 3 months. Methods. The intervention comprised eight weekly group sessions (meditation and CLBP-specific CBT components) and 30 minutes/day, 6 days/week of at-home practice. Outcome measures were collected at baseline, 8, and 26 weeks: primary-pain severity (Brief Pain Inventory) and function/disability (Oswestry Disability Index); secondary-pain acceptance, opioid dose, pain sensitivity to thermal stimuli, and serum pain-sensitive biomarkers (Interferon-γ; Tumor Necrosis Factor-α; Interleukins 1ß and 6; C-reactive Protein). Results. Thirty-five (21 experimental, 14 control) participants were enrolled and completed the study. They were 51.8 ± 9.7 years old, 80% female, with severe CLBP-related disability (66.7 ± 11.4), moderate pain severity (5.8 ± 1.4), and taking 148.3 ± 129.2 mg/day of MED. Results of the intention-to-treat analysis showed that, compared with controls, the meditation-CBT group reduced pain severity ratings during the study (P = 0.045), with between-group difference in score change reaching 1 point at 26 weeks (95% Confidence Interval: 0.2,1.9; Cohen’s d = 0.86), and decreased pain sensitivity to thermal stimuli (P < 0.05), without adverse events. Exploratory analyses suggested a relationship between the extent of meditation practice and the magnitude of intervention benefits. Conclusions. Meditation-CBT intervention reduced pain severity and sensitivity to experimental thermal pain stimuli in patients with opioid-treated CLBP. PMID:26968850
Genetic studies of human neuropathic pain conditions: a review
Zorina-Lichtenwalter, Katerina; Parisien, Marc; Diatchenko, Luda
2018-01-01
Abstract Numerous studies have shown associations between genetic variants and neuropathic pain disorders. Rare monogenic disorders are caused by mutations of substantial effect size in a single gene, whereas common disorders are likely to have a contribution from multiple genetic variants of mild effect size, representing different biological pathways. In this review, we survey the reported genetic contributors to neuropathic pain and submit them for validation in a 150,000-participant sample of the U.K. Biobank cohort. Successfully replicated association with a neuropathic pain construct for 2 variants in IL10 underscores the importance of neuroimmune interactions, whereas genome-wide significant association with low back pain (P = 1.3e-8) and false discovery rate 5% significant associations with hip, knee, and neck pain for variant rs7734804 upstream of the MAT2B gene provide evidence of shared contributing mechanisms to overlapping pain conditions at the molecular genetic level. PMID:29240606
Anxiety and stress can predict pain perception following a cognitive stress.
Hoeger Bement, Marie; Weyer, Andy; Keller, Manda; Harkins, April L; Hunter, Sandra K
2010-08-04
Hoeger Bement, M.K., A. Weyer, M. Keller, A. Harkins, and S.K. Hunter. Anxiety and stress can predict pain perception following a cognitive stressor. PHYSIOL BEHAV 000-000. The purpose of this study was to investigate the influence of a cognitive stressor on pain perception and determine individual characteristics that may predict the pain response. Twenty-five subjects participated in three sessions: one familiarization and two experimental. The experimental sessions involved measurement of pain perception before and after 1) mental math tasks (stressor session) and 2) quiet rest (control session). Pain threshold and ratings were assessed with a mechanical noxious stimulus. Changes in stress and anxiety were examined with self-reported and physiological measures including questionnaires, visual analogue scales, and salivary cortisol levels. During the control session, stress and anxiety decreased and pain reports remain unchanged. During the stressor session, stress and anxiety increased and pain reports were variable among subjects. Based on the pain response to mental math, subjects were divided into three groups (increase, decrease or no change in pain). The increase-pain group (n=8) had lower baseline stress and anxiety, lower baseline pain reports, and large anxiety response following the mental math. In contrast, the decrease-pain group (n=9) had higher baseline stress and anxiety levels, higher baseline pain reports, and a large increase in cortisol levels. Thus, the differential response in the changes in pain perception was related to anxiety and stress levels prior to and during the cognitive stressor, indicating that psychosocial characteristics can help determine the stress-induced pain response. Copyright 2010 Elsevier Inc. All rights reserved.
Schmidt, Stefan; Naranjo, José Raúl; Brenneisen, Christina; Gundlach, Julian; Schultz, Claudia; Kaube, Holger; Hinterberger, Thilo; Jeanmonod, Daniel
2012-01-01
Objectives Several recent studies report the presence of a specific EEG pattern named Thalamocortical Dysrhythmia (TCD) in patients with severe chronic neurogenic pain. This is of major interest since so far no neuroscientific indicator of chronic pain could be identified. We investigated whether a TCD-like pattern could be found in patients with moderate chronic back pain, and we compared patients with neuropathic and non-neuropathic pain components. We furthermore assessed the presence of psychopathology and the degree of psychological functioning and examined whether the strength of the TCD-related EEG markers is correlated with psychological symptoms and pain ratings. Design Controlled clinical trial with age and sex matched healthy controls. Methods Spontaneous EEG was recorded in 37 back pain patients and 37 healthy controls. Results We were not able to observe a statistically significant TCD effect in the EEG data of the whole patient group, but a subsample of patients with evidence for root damage showed a trend in this direction. Pain patients showed markedly increased psychopathology. In addition, patients' ratings of pain intensity within the last 1 to 12 months showed strong correlations with EEG power, while psychopathology was correlated to the peak frequency. Conclusion Out of several possible interpretations the most likely conclusion is that only patients with severe pain as well as root lesions with consecutive thalamic deafferentation develop the typical TCD pattern. Our primary method of defining ‘neuropathic pain’ could not reliably determine if such a deafferentation was present. Nevertheless the analysis of a specific subsample as well as correlations between pain ratings, psychopathology and EEG power and peak frequency give some support to the TCD concept. Trial Registration ClinicalTrials.gov NCT00744575 PMID:22431961
Williams, Suzanne; Holzhauser, Kerri; Bonney, Donna; Burmeister, Elizabeth; Gilhotra, Yuri; Oliver, Randall; Gordon, Kerry
2012-08-01
In 2007, the Mater Children's Hospital Emergency Department participated in the Emergency Care Pain Management Initiative funded by the National Health and Medical Research Council National Institute of Clinical Studies (NHMRC-NICS). The findings of this NHMRC-NICS research across eleven paediatric emergency departments highlighted deficits in pain management of abdominal pain. Specifically pain assessment, timeliness of analgesia, and pain management guidelines were found to be lacking. In response to the NICS report local practice was reviewed and a pilot research project undertaken to develop a clinical guideline for the pain management of abdominal pain in children presenting to the emergency department. The guideline was developed by an expert panel and trialled using a pre and post intervention design. The results demonstrated improved compliance to assessment and documentation of pain scores and assimilation of the best practice principles recommended in the guideline. This project raised local awareness in the pain management of abdominal pain and provides baseline information for future improvement. The guideline has been trialled in the clinical setting of paediatric emergency and has the potential to improve pain management practices in children presenting to the emergency department with abdominal pain. Copyright © 2012 College of Emergency Nursing Australasia Ltd. Published by Elsevier Ltd. All rights reserved.
Idvall, Ewa; Holm, Charlotta; Runeson, Ingrid
2005-09-01
Tonsillectomy is one of the most common paediatric surgical procedures. This study aimed to investigate children's experience of pain and the nonpharmacological strategies that they used to manage pain after tonsillectomy. A further aim was to investigate parental views on these same phenomena. Six children (aged seven to 18 years) and their parents (four mothers and two fathers) were interviewed separately on the day after tonsillectomy. The data were analysed using a qualitative approach. Pain experiences were divided into the categories of physiological pain and psychological pain. Children rated their 'worst pain' during the past 24 hours between 6 and 10 (visual analogue scale, 0-10). The non-pharmacological strategies used most frequently to manage pain were thermal regulation (physical method) and distraction (cognitive-behavioural method) according to the framework used. Specific non-pharmacological strategies for pain management relative to different surgical procedures need to be considered.
Visuospatial and verbal memory in chronic pain patients: an explorative study.
Busch, Hillevi; Montgomery, William; Melin, Bo; Lundberg, Ulf
2006-09-01
Cognitive bias, such as selective memory for pain-related information, is frequently observed in chronic pain patients and is assessed mostly using verbal material. Beside word lists, the current study used photographs of people presenting pain behaviors to assess memory bias in chronic pain patients. Chronic pain patients were hypothesized to show better recall of pain-related words and pictures as compared to pain-free controls. Twenty-eight female chronic neck patients and 28 pain-free female controls completed two computerized pictorial memory games and two word recall tasks. Patients and controls performed equally well in the neutral pictorial memory game. In the pain-related game, patients performed significantly worse than controls. No significant differences were found in the word recall task. The result is discussed in terms of cognitive avoidance.
Ethnic differences in pain perception and patient-controlled analgesia usage for postoperative pain.
Tan, Ene-Choo; Lim, Yvonne; Teo, Yik-Ying; Goh, Rachelle; Law, Hai-Yang; Sia, Alex T
2008-09-01
There are reports suggesting that sensitivity to and tolerance of both clinical and experimental pain differ among ethnic groups. We examined self-rated pain score and morphine usage in 1034 women who underwent elective lower cesarian section (LSCS) for their deliveries. Data on pain scores and amount of total morphine use according to patient-controlled analgesia were collected every 4 hours. Overall, lowest pain scores were recorded 12 hours after surgery and highest at 24 hours. Morphine consumption was highest within the first 4 hours and lowest between 12 and 16 hours. There were statistically significant ethnic group differences in pain scores (P = 1.7 x 10(-7)) and morphine usage (P = 2.8 x 10(-15)) between ethnic groups, with Indians having the highest mean pain score and using the highest amount of morphine. The ethnic differences in pain score and morphine self-administration persisted after controlling for age, body mass index, and duration of operation. Our findings of highly significant ethnic group difference in self-reported pain level and the amount of analgesia self-administered may have implications on optimal management of acute postoperative pain. Inadequate management of pain after cesarian deliveries might affect the emotional well-being and physical recovery of patients and affect mother-child bonding.
Campbell, Claudia M; Buenaver, Luis F; Raja, Srinivasa N; Kiley, Kasey B; Swedberg, Lauren J; Wacnik, Paul W; Cohen, Steven P; Erdek, Michael A; Williams, Kayode A; Christo, Paul J
2015-07-01
Spinal cord stimulation (SCS) has become a widely used treatment option for a variety of pain conditions. Substantial variability exists in the degree of benefit obtained from SCS and patient selection is a topic of expanding interest and importance. However, few studies have examined the potential benefits of dynamic quantitative sensory testing (QST) to develop objective measures of SCS outcomes or as a predictive tool to help patient selection. Psychological characteristics have been shown to play an important role in shaping individual differences in the pain experience and may aid in predicting responses to SCS. Static laboratory pain-induction measures have also been examined in their capacity for predicting SCS outcomes. The current study evaluated clinical, psychological and laboratory pain measures at baseline, during trial SCS lead placement, as well as 1 month and 3 months following permanent SCS implantation in chronic pain patients who received SCS treatment. Several QST measures were conducted, with specific focus on examination of dynamic models (central sensitization and conditioned pain modulation [CPM]) and their association with pain outcomes 3 months post SCS implantation. Results suggest few changes in QST over time. However, central sensitization and CPM at baseline were significantly associated with clinical pain at 3 months following SCS implantation, controlling for psycho/behavioral factors and pain at baseline. Specifically, enhanced central sensitization and reduced CPM were associated with less self-reported pain 3 months following SCS implantation. These findings suggest a potentially important role for dynamic pain assessment in individuals undergoing SCS, and hint at potential mechanisms through which SCS may impart its benefit. Wiley Periodicals, Inc.
Butler, Stephen; Peterson, Magnus; Eriksson, Margaretha
2015-01-01
Objectives To describe referred pain patterns provoked from intra-pelvic structures in women with chronic pelvic pain (CPP) persisting after childbirth with the purpose to improve diagnostics and give implications for treatment. Materials and Methods In this descriptive and comparative study 36 parous women with CPP were recruited from a physiotherapy department waiting list and by advertisements in newspapers. A control group of 29 parous women without CPP was consecutively assessed for eligibility from a midwifery surgery. Inclusion criterion for CPP was: moderate pain in the sacral region persisting at least six months after childbirth confirmed by pelvic pain provocation tests. Exclusion criteria in groups with and without CPP were: persistent back or pelvic pain with onset prior to pregnancy, previous back surgery and positive neurological signs. Pain was provoked by palpation of 13 predetermined intra-pelvic anatomical landmarks. The referred pain distribution was expressed in pain drawings and described in pain maps and calculated referred pain areas. Results Pain provoked by palpation of the posterior intra-pelvic landmarks was mostly referred to the sacral region and pain provoked by palpation of the ischial and pubic bones was mostly referred to the groin and pubic regions, with or without pain referred down the ipsilateral leg. The average pain distribution area provoked by palpation of all 13 anatomical landmarks was 30.3 mm² (19.2 to 53.7) in women with CPP as compared to 3.2 mm² (1.0 to 5.1) in women without CPP, p< 0.0001. Conclusions Referred pain patterns provoked from intra-pelvic landmarks in women with CPP are consistent with sclerotomal sensory innervation. Magnification of referred pain patterns indicates allodynia and central sensitization. The results suggest that pain mapping can be used to evaluate and confirm the pain experience among women with CPP and contribute to diagnosis. PMID:25793999
Pain in dementia: prevalence and associated factors: protocol of a multidisciplinary study.
van Kooten, Janine; Delwel, Suzanne; Binnekade, Tarik T; Smalbrugge, Martin; van der Wouden, Johannes C; Perez, Roberto S G M; Rhebergen, Didi; Zuurmond, Wouter W A; Stek, Max L; Lobbezoo, Frank; Hertogh, Cees M P M; Scherder, Erik J A
2015-03-21
Pain is a common problem in people with dementia, however the exact prevalence of pain in dementia subtypes, e.g. Alzheimer's Disease (AD), Vascular Dementia (VaD), Frontotemporal Dementia (FTD) and dementia with Lewy Bodies (DLB), is unknown, as is the relation between pain and the different subtypes of dementia. In this study, the prevalence of pain in people with dementia will be investigated per dementia subtype and the relationship between the various subtypes of dementia and the presence of specific types of pain (i.e. musculoskeletal pain, neuropathic pain and orofacial pain) will be examined. Secondly, associations between various types of pain, cognitive functioning, neuropsychiatric symptoms and quality of life in people with dementia will be examined. A third purpose is to study the value of the assessment of autonomic responses in assessing pain in people with dementia. Finally, the effect of feedback to the attending physician on the presence of pain, based on examination by investigators with backgrounds in neuropsychology, geriatric dentistry and elderly care medicine, will be evaluated. A cross-sectional, partially longitudinal observational study in 400 participants with dementia, aged 60 years and older. Participants will be recruited from an outpatient memory clinic and dementia special care units. All participants will be examined by an elderly care medicine trainee, a dentist with experience in geriatric dentistry, and a neuropsychologist. The primary outcome is presence of pain. Secondary outcomes will include oral health, autonomic responses to pain stimulus, vital sensibility and gnostic sensibility, musculoskeletal examination, cognitive functioning, neuropsychiatric symptoms, and quality of life. This study will help to enhance our knowledge regarding the prevalence of different types of pain in different dementia subtypes i.e. AD, VaD, FTD and DLB. This study also aims to contribute to a better understanding of oral health status in
Botulinum Toxin for the Treatment of Neuropathic Pain
Park, JungHyun; Park, Hue Jung
2017-01-01
Botulinum toxin (BoNT) has been used as a treatment for excessive muscle stiffness, spasticity, and dystonia. BoNT for approximately 40 years, and has recently been used to treat various types of neuropathic pain. The mechanism by which BoNT acts on neuropathic pain involves inhibiting the release of inflammatory mediators and peripheral neurotransmitters from sensory nerves. Recent journals have demonstrated that BoNT is effective for neuropathic pain, such as postherpetic neuralgia, trigeminal neuralgia, and peripheral neuralgia. The purpose of this review is to summarize the experimental and clinical evidence of the mechanism by which BoNT acts on various types of neuropathic pain and describe why BoNT can be applied as treatment. The PubMed database was searched from 1988 to May 2017. Recent studies have demonstrated that BoNT injections are effective treatments for post-herpetic neuralgia, diabetic neuropathy, trigeminal neuralgia, and intractable neuropathic pain, such as poststroke pain and spinal cord injury. PMID:28837075
Franceschi, F; Togni, S; Belcaro, G; Dugall, M; Luzzi, R; Ledda, A; Pellegrini, L; Eggenhoffner, R; Giacomelli, L
2016-10-01
Several experimental studies and clinical trials support the potential of Boswellia serrata extracts (BSE) for the treatment of various inflammatory diseases. The aim of this registry study was to assess the safety and the efficacy of a novel lecithin-based delivery form of Boswellia serrata extract (Casperome®) in the supportive management of osteo-muscular pain. 52 healthy young rugby players with acute knee pain and inflammation were recruited. Informed participants freely decided to follow either a standard management (SM) to control joint pain (control group = 27) or SM associated with oral daily supplementation with Casperome® (supplement group =25). Parameters associated with osteo-muscular pain and inflammation, and measurements of joint health and functions were assessed at the inclusion and after a 4-week supplementation. A significant beneficial effect of Casperome® vs SM alone was observed for all the parameters evaluated, namely: local pain on effort; pain-free walking distance (treadmill test); minimal joint effusion; structural damage (joint, tendons, muscles) and intramuscular hematomas; thermal imaging of the anterior knee; Visual Analog Scale for Pain (VAS Pain); need for concomitant drugs and medical attention; measurement of inflammatory biomarkers. Our registry study suggests that Casperome® supplementation could represent an effective and safe, integrated approach for the treatment of osteo-muscular pain and inflammation.
DeClaire, Jeffrey H; Aiello, Paige M; Warritay, Olayinka K; Freeman, Dwight C
2017-09-01
We compared the effectiveness of liposomal bupivacaine to ropivacaine, each as part of multimodal pain management, in total knee arthroplasty (TKA) postoperative pain control. This prospective, double blind study randomized 96 TKA patients into a control group (periarticular injection of ropivacaine, ketorolac, morphine, and epinephrine in saline; 100cc) or an experimental group (periarticular injection of bupivacaine, ketorolac, morphine, and epinephrine in saline; 80cc plus 1.3% liposomal bupivacaine 20cc; total injection 100cc). The postoperative use of narcotics, visual analog pain scores, hours to ambulate 100 feet, and length of hospital stay were recorded. There was no significant difference between the two groups (control N = 49, experiment N = 47) in mean narcotic use per hour, total narcotic use during hospital stay, time to ambulate 100 feet, length of hospital stay, or visual analog score for pain postoperatively. There is no benefit in the use of liposomal bupivacaine compared with ropivacaine for postoperative pain control in TKA. Copyright © 2017 Elsevier Inc. All rights reserved.
Mittinty, Manasi M; Vanlint, Simon; Stocks, Nigel; Mittinty, Murthy N; Moseley, G Lorimer
2018-04-25
Chronic pain affects an estimated 1 in 10 adults globally regardless of age, gender, ethnicity, income or geography. Chronic pain, a multifactorial problem requires multiple interventions. One intervention which demonstrates promising results to patient reported outcomes is pain education. However, patient perspective on pain education and its impact remains fairly unknown. A cross-sectional study involving individuals with chronic pain examined their perspectives on pain education; did it change their understanding about their pain and self-management and did it have any impact on their perceived pain intensity and recovery. The study complied with CHERRIES guidelines and the protocol was locked prior to data collection. Primary outcomes were pain intensity and participants' expectation of recovery. Univariate and multiple logistic regressions were used to analyze the data. Five hundred and seventy three people participated; full data sets were available for 465. Participants who observed changes in their pain cognition and self-management following pain education reported lower pain intensity and greater expectation of recovery than participants who did not observe changes to cognition and management. The results suggest that individuals who observed changes to pain cognition and self-management on receiving pain education reported lower pain intensity and higher expectations of recovery than their counterparts who did not perceive any changes to pain cognition and self-management. Pain intensity and expectations about recovery are primary considerations for people in pain. What influences these factors is not fully understood, but education about pain is potentially important. The results suggest that individuals who observed changes to pain cognition and self-management on receiving pain education reported lower pain intensity and higher expectations of recovery than their counterparts who did not perceive any changes to pain cognition and self-management. The
Nurse Perceptions of Pain in Pediatric Traumatic Brain Injury: A Pilot Study.
McCaa, Robin
2017-01-01
Pain assessment in the pediatric population is challenging because of age, developmental stage, and patient cooperation. Cognitive impairment, impaired communication, and physical disability that may accompany traumatic brain injury (TBI) further complicate pain assessments. A pilot descriptive qualitative research study was conducted to investigate nurse perceptions of pain in pediatric patients diagnosed with TBI. Specifically, this study sought to answer the following questions: a) Is pain accurately assessed in this population? b) Is pain adequately treated in this population? and c) What obstacles exist, if any, to the assessment and treatment of pain? A convenience sample of three registered nurses employed in a pediatric neurosurgery setting participated in this study. Each nurse participated in one individual, semi-structured, face-to-face interview lasting approximately 30 minutes. Interviews were transcribed verbatim and analyzed for common themes. Common themes identified across all interviews were a) challenging assessments; b) limited, although effective, treatments; and c) communication as an area of opportunity for improvement. Implications for practice and policy include a need for more sensitive pain assessment tools to improve the objectivity and accuracy of pain assessment, clarification of care priorities and organization of care from clinical and management perspectives, and additional research in alternative pain treatments for this population. Findings from this study will guide the development of a larger, more comprehensive study, with the aim of improving practice and policy in pain management for this population.
Cold Pressor Pain Sensitivity in Twins Discordant for Chronic Fatigue Syndrome
Ullrich, Phil; Afari, Niloofar; Jacobsen, Clemma; Goldberg, Jack; Buchwald, Dedra
2010-01-01
Objective Individuals with chronic fatigue syndrome (CFS) experience many pain symptoms. The present study examined whether pain and fatigue ratings and pain threshold and tolerance levels for cold pain differed between twins with CFS and their cotwins without CFS. Design Cotwin control design to assess cold pain sensitivity, pain, and fatigue in monozygotic twins discordant for CFS. Patients and Setting Fifteen twin pairs discordant for CFS recruited from the volunteer Chronic Fatigue Twin Registry at the University of Washington. Results Although cold pain threshold and tolerance levels were slightly lower in twins with CFS than their cotwins without CFS, these differences failed to reach statistical significance. Subjective ratings of pain and fatigue at multiple time points during the experimental protocol among twins with CFS were significantly higher than ratings of pain (p = 0.003) and fatigue (p < 0.001) by their cotwins without CFS. Conclusions These results, while preliminary, highlight the perceptual and cognitive components to the pain experience in CFS. Future studies should focus on examining the heritability of pain sensitivity and the underlying mechanisms involved in the perception of pain sensitivity in CFS. PMID:17371408
Sklempe Kokic, Iva; Ivanisevic, Marina; Uremovic, Melita; Kokic, Tomislav; Pisot, Rado; Simunic, Bostjan
2017-03-06
To investigate the effect of a supervised, structured exercise programme on the occurrence and severity of pregnancy-related lumbopelvic pain. Randomized controlled trial. A total of 45 pregnant women were randomly assigned to 2 groups: an experimental group (n = 20; mean age 32.8 (standard deviation (SD) 3.6) years) and a control group (n = 22; mean age 32.2 years (SD 4.9)). Exercise intervention for the experimental group consisted of aerobic and resistance exercises performed bi-weekly from the date of inclusion into the study until the end of pregnancy, together with at least 30 min of brisk daily walks. A numeric rating scale, Roland-Morris Disability Questionnaire (RMDQ), and Pelvic Girdle Questionnaire (PGQ) were used to measure outcomes. The control group received only standard antenatal care. There were significant differences between the 2 groups on the numeric rating scale, PGQ and RMDQ scores in the 36th week of pregnancy (p = 0.017; p = 0.005; p < 0.001, respectively) in favour of the experimental group. The exercise programme had a beneficial effect on the severity of lumbopelvic pain in pregnancy, reducing the intensity of pain and the level of disability experienced as a result.
Efficient conditioned pain modulation despite pain persistence in painful diabetic neuropathy.
Granovsky, Yelena; Nahman-Averbuch, Hadas; Khamaisi, Mogher; Granot, Michal
2017-05-01
Alleviation of pain, by either medical or surgical therapy, is accompanied by transition from less efficient, or pro-nociceptive, to efficient conditioned pain modulation (CPM). Spontaneous decrease or resolution of pain with disease progression is reported for some patients with painful diabetic neuropathy (PDN). To explore whether CPM changes similarly in parallel to spontaneous resolution of pain in PDN patients. In this cross-sectional study, thirty-three patients with PDN underwent psychophysical assessment of pain modulation on the forearm, remote from the clinical pain. Pain duration was not correlated with neuropathic pain intensity, yet, it correlated with CPM efficiency; patients with longer pain duration had same pain level, but more efficient CPM than those with short-pain duration (ρ = -0.417; P = 0.025, Spearman correlation). Patients with pain more than 2 years (median split) expressed efficient CPM that was not different from that of healthy controls. These patients also had lower temporal summation of pain than the short-pain duration patients group ( P < 0.05). The 2 patient groups did not differ in clinical pain characteristics or use of analgesics. Pro-nociception, expressed by less efficient CPM and high temporal summation that usually accompanies clinical painful conditions, seems to "normalize" with chronicity of the pain syndrome. This is despite continuing pain, suggesting that pro-nociceptivity in pain syndromes is multifactorial. Because the pain modulation profile affects success of therapy, this suggests that different drugs might express different efficacy pending on duration of the pain in patients with PDN.
Efficient conditioned pain modulation despite pain persistence in painful diabetic neuropathy
Granovsky, Yelena; Nahman-Averbuch, Hadas; Khamaisi, Mogher; Granot, Michal
2017-01-01
Abstract Introduction: Alleviation of pain, by either medical or surgical therapy, is accompanied by transition from less efficient, or pro-nociceptive, to efficient conditioned pain modulation (CPM). Spontaneous decrease or resolution of pain with disease progression is reported for some patients with painful diabetic neuropathy (PDN). Objectives: To explore whether CPM changes similarly in parallel to spontaneous resolution of pain in PDN patients. Methods: In this cross-sectional study, thirty-three patients with PDN underwent psychophysical assessment of pain modulation on the forearm, remote from the clinical pain. Results: Pain duration was not correlated with neuropathic pain intensity, yet, it correlated with CPM efficiency; patients with longer pain duration had same pain level, but more efficient CPM than those with short-pain duration (ρ = −0.417; P = 0.025, Spearman correlation). Patients with pain more than 2 years (median split) expressed efficient CPM that was not different from that of healthy controls. These patients also had lower temporal summation of pain than the short-pain duration patients group (P < 0.05). The 2 patient groups did not differ in clinical pain characteristics or use of analgesics. Conclusion: Pro-nociception, expressed by less efficient CPM and high temporal summation that usually accompanies clinical painful conditions, seems to “normalize” with chronicity of the pain syndrome. This is despite continuing pain, suggesting that pro-nociceptivity in pain syndromes is multifactorial. Because the pain modulation profile affects success of therapy, this suggests that different drugs might express different efficacy pending on duration of the pain in patients with PDN. PMID:29392208
Ickmans, Kelly; Malfliet, Anneleen; De Kooning, Margot; Goudman, Lisa; Hubloue, Ives; Schmitz, Tom; Goubert, Dorien; Aguilar-Ferrandiz, Maria Encarnacion
2017-09-01
Individuals with chronic whiplash associated disorders (WAD) present persistent pain in the absence of structural pathology. In these people, altered central pain processing and central sensitization are observed. The role of personal factors, such as gender and age, on pain processing mechanisms in chronic WAD, however, is still unclear. This study investigated possible gender- and age-related differences in self-reported and experimental pain measurements in people with chronic WAD. Besides the exercise-induced response on pain measurements between gender and age subgroups was recorded. Case-control study. University Hospital, Brussels. Self-reported pain and experimental pain measurements (pressure pain thresholds [PPT], occlusion cuff pressure, temporal summation, and conditioned pain modulation) were performed in 52 individuals (26 chronic WAD patients and 26 healthy controls), before and after a submaximal cycle exercise. Lower PPTs and occlusion cuff pressures were shown in chronic WAD in comparison with healthy controls. No gender and age differences regarding PPTs, occlusion cuff pressures and conditioned pain modulation were found in chronic WAD. Within the chronic WAD group, men showed higher self-reported pain compared to women and younger adults showed enhanced generalized pain facilitation compared to older adults. In addition, chronic WAD patients are able to inhibit exercise-induced hyperalgesia, but no gender and age differences in pain response following exercise were found. This study was sufficiently powered to detect differences between the chronic WAD and control group. However, a sufficient power was not reached when patients were divided in age and gender groups. Furthermore, only mechanical stimuli were included in the experimental pain measurements. Besides, psychosocial factors were not taken into account. Some alterations of altered pain processing are present in chronic WAD patients, however not in response to exercise. No gender and
Tai Chi for Posttraumatic Stress Disorder and Chronic Musculoskeletal Pain: A Pilot Study.
Tsai, Pao-Feng; Kitch, Stephanie; Chang, Jason Y; James, G Andrew; Dubbert, Patricia; Roca, J Vincent; Powers, Cheralyn H
2018-06-01
Explore the feasibility of a Tai Chi intervention to improve musculoskeletal pain, emotion, cognition, and physical function in individuals with posttraumatic stress disorder. Two-phase, one-arm quasi-experimental design. Phase 1: 11 participants completed one Tai Chi session, feasibility questionnaire, and were offered participation in Phase 2, a 12-week Tai Chi intervention. Ten participants participated in Phase 2. Pain intensity, interference, physical function scales, an emotional battery, and cognition tests were used for pre- and postintervention outcome measures. Paired t tests and thematic analysis were used for analysis. In Phase 1, most felt Tai Chi would benefit health (90.9%) and expressed interest in continuing Tai Chi (6.73 out of 7). Phase 2 results showed improvement in fear-affect (raw t = -2.64, p = .03; age adjusted t = -2.90, p = .02), fear-somatic arousal (raw t = -2.53, p = .035), List Sorting Working Memory (raw t = 2.62, p = .031; age adjusted t = 2.96, p = .018), 6-Minute Walk Test ( t = 3.541, p = .008), and current level of Pain Intensity ( t = -4.00, p = .004). Tai Chi is an acceptable, holistic treatment to individuals with musculoskeletal pain and posttraumatic stress disorder. It may reduce pain, improve emotion, memory, and physical function.
Rathleff, Camilla Rams; Stephenson, Aoife; Mellor, Rebecca; Matthews, Mark; Crossley, Kay; Vicenzino, Bill
2017-01-01
Patellofemoral Pain (PFP) is highly prevalent among adults and adolescents. Localized mechanical hyperalgesia around the knee and tibialis anterior have been observed in people with PFP, but limited knowledge of potential manifestations of central sensitisation exists. The aims of this study were to study conditioned pain modulation (CPM) and wide-spread hyperalgesia in adults with PFP. This assessor-blinded cross-sectional study design compared CPM and mechanical pressure pain thresholds (PPT) between 33 adults (23 females) diagnosed with PFP and 32 age and sex matched pain-free controls. The investigator taking the PPT measurements was blinded to which participants had PFP. PPTs were reliably measured using a Somedic hand-held pressure algometer at three sites: 1) The centre of the patella, 2) the tibialis anterior muscle and 3) a remote site on the lateral epicondyle. For the assessment of CPM, experimental pain was induced to the contralateral hand by immersion into a cold water bath (conditioning stimulus), and assessment of PPTs (the test stimulus) was performed before and immediately after the conditioning stimulation. On average, the CPM paradigm induced a significant increase in PPTs across the three sites (6.3–13.5%, P<0.05), however there was no difference in CPM between young adults with PFP compared to the control group, (F(1,189) = 0.39, P = 0.89). There was no difference in mechanical PPTs between the two groups (F(1,189) = 0.03, P = 0.86). Contrary to our a-priori hypothesis, we found no difference in CPM or PPT between young adults with PFP and age and sex matched pain-free controls. PMID:29220355
Using non-contact therapeutic touch to manage post-surgical pain in the elderly.
McCormack, Guy L
2009-01-01
The purpose of this study was to investigate the effects of non-contact therapeutic touch on post-surgical pain in an elderly population receiving occupational therapy in an acute care hospital unit in the United States. Ninety participants were randomly assigned to three groups (experimental, control and placebo) using a three-group experimental pre-test-post-test design and a randomized clinical trial. The experimental group received the non-contact touch intervention, the control group received routine care and the placebo group received the sound of a metronome set at a steady slow pace. Objective measures included the Memorial Pain Scale, the Tellegen Absorption Scale, the Health Attribution Scale and measures of pulse rate and pupil size, which were performed as repeated measures. In the experimental group, 22 out of 30 (73%) demonstrated a statistically significant decrease in pain intensity scores from pre-test to post-test (t [7] = 7.24, p < 0.01) and were better able to participate in occupations. Further research is recommended to replicate this study. 2009 John Wiley & Sons, Ltd
Tse, Mimi M Y; Chan, M F; Benzie, Iris F F
2005-01-01
The prevalence of unrelieved postoperative pain is high and may lead to adverse effects including prolonged hospitalization and delayed recovery. Distraction may be an effective pain-relieving strategy, and can be implemented by several means including affective imaging, games, and possibly music. The aim of this study was to explore the effect of music therapy on postoperative pain. Fifty-seven patients (24 females, 33 males; mean +/- SD age 39.9 +/- 14.35 years [range 15 to 69 years] were matched for age and sex and then nonselectively assigned to either an experimental (n = 27) or a control (n = 30) group. Music was played intermittently to members of the experimental group during the first 24 hour postoperative period. Pain intensity was measured using the Pain Verbal Rating Scales (VRS). Significant decreases in pain intensity over time were found in the experimental group compared to the control group (p < 0.0001). In addition, the experimental group had a lower systolic blood pressure and heart rate, and took fewer oral analgesics for pain. These findings suggest that music therapy is an effective nonpharmacologic approach for postoperative pain management.
Hinson, Jeremiah S.; Mistry, Binoy; Hsieh, Yu-Hsiang; Risko, Nicholas; Scordino, David; Paziana, Karolina; Peterson, Susan; Omron, Rodney
2017-01-01
Introduction Our goal was to reduce ordering of coagulation studies in the emergency department (ED) that have no added value for patients presenting with chest pain. We hypothesized this could be achieved via implementation of a stopgap measure in the electronic medical record (EMR). Methods We used a pre and post quasi-experimental study design to evaluate the impact of an EMR-based intervention on coagulation study ordering for patients with chest pain. A simple interactive prompt was incorporated into the EMR of our ED that required clinicians to indicate whether patients were on anticoagulation therapy prior to completion of orders for coagulation studies. Coagulation order frequency was measured via detailed review of randomly sampled encounters during two-month periods before and after intervention. We classified existing orders as clinically indicated or non-value added. Order frequencies were calculated as percentages, and we assessed differences between groups by chi-square analysis. Results Pre-intervention, 73.8% (76/103) of patients with chest pain had coagulation studies ordered, of which 67.1% (51/76) were non-value added. Post-intervention, 38.5% (40/104) of patients with chest pain had coagulation studies ordered, of which 60% (24/40) were non-value added. There was an absolute reduction of 35.3% (95% confidence interval [CI]: 22.7%, 48.0%) in the total ordering of coagulation studies and 26.4% (95% CI: 13.8%, 39.0%) in non-value added order placement. Conclusion Simple EMR-based interactive prompts can serve as effective deterrents to indiscriminate ordering of diagnostic studies. PMID:28210363
Hinson, Jeremiah S; Mistry, Binoy; Hsieh, Yu-Hsiang; Risko, Nicholas; Scordino, David; Paziana, Karolina; Peterson, Susan; Omron, Rodney
2017-02-01
Our goal was to reduce ordering of coagulation studies in the emergency department (ED) that have no added value for patients presenting with chest pain. We hypothesized this could be achieved via implementation of a stopgap measure in the electronic medical record (EMR). We used a pre and post quasi-experimental study design to evaluate the impact of an EMR-based intervention on coagulation study ordering for patients with chest pain. A simple interactive prompt was incorporated into the EMR of our ED that required clinicians to indicate whether patients were on anticoagulation therapy prior to completion of orders for coagulation studies. Coagulation order frequency was measured via detailed review of randomly sampled encounters during two-month periods before and after intervention. We classified existing orders as clinically indicated or non-value added. Order frequencies were calculated as percentages, and we assessed differences between groups by chi-square analysis. Pre-intervention, 73.8% (76/103) of patients with chest pain had coagulation studies ordered, of which 67.1% (51/76) were non-value added. Post-intervention, 38.5% (40/104) of patients with chest pain had coagulation studies ordered, of which 60% (24/40) were non-value added. There was an absolute reduction of 35.3% (95% confidence interval [CI]: 22.7%, 48.0%) in the total ordering of coagulation studies and 26.4% (95% CI: 13.8%, 39.0%) in non-value added order placement. Simple EMR-based interactive prompts can serve as effective deterrents to indiscriminate ordering of diagnostic studies.
King, Christopher D.; Wong, Fong; Currie, Tom; Mauderli, Andre P.; Fillingim, Roger B.; Riley, Joseph L.
2013-01-01
Females with Irritable Bowel Syndrome (IBS) and Temporomandibular Disorder (TMD) are characterized by enhanced sensitivity to experimental pain. One possible explanation for this observation is deficiencies in pain modulation systems like Diffuse Noxious Inhibitory Control (DNIC). In a few studies that used brief stimuli, chronic pain patients demonstrate reduced DNIC. The purpose of this study was to compare sensitivity to prolonged heat pain and the efficacy of DNIC in controls to IBS and TMD patients. Heat pain (experimental stimulus; 44.0-49.0°C), which was applied to left palm, was continuously rated during three 30-second trials across three separate testing sessions under the following conditions: without a conditioning stimulus; during concurrent immersion of the right foot in a 23.0°C (control); and during noxious cold immersion in a (DNIC; 8.0-16.0°C) water bath. Compared to controls, IBS and TMD patients reported increased sensitivity to heat pain and failed to demonstrate pain inhibition due to DNIC. Controls showed a significant reduction in pain during the DNIC session. These findings support the idea that chronic pain patients are not only more pain sensitive and demonstrate reduced pain inhibition by pain, possibly because of dysfunction of endogenous pain inhibition systems. PMID:19278784
Acute psychosocial stress reduces pain modulation capabilities in healthy men.
Geva, Nirit; Pruessner, Jens; Defrin, Ruth
2014-11-01
Anecdotes on the ability of individuals to continue to function under stressful conditions despite injuries causing excruciating pain suggest that acute stress may induce analgesia. However, studies exploring the effect of acute experimental stress on pain perception show inconsistent results, possibly due to methodological differences. Our aim was to systematically study the effect of acute stress on pain perception using static and dynamic, state-of-the-art pain measurements. Participants were 29 healthy men who underwent the measurement of heat-pain threshold, heat-pain intolerance, temporal summation of pain, and conditioned pain modulation (CPM). Testing was conducted before and during exposure to the Montreal Imaging Stress Task (MIST), inducing acute psychosocial stress. Stress levels were evaluated using perceived ratings of stress and anxiety, autonomic variables, and salivary cortisol. The MIST induced a significant stress reaction. Although pain threshold and pain intolerance were unaffected by stress, an increase in temporal summation of pain and a decrease in CPM were observed. These changes were significantly more robust among individuals with stronger reaction to stress ("high responders"), with a significant correlation between the perception of stress and the performance in the pain measurements. We conclude that acute psychosocial stress seems not to affect the sensitivity to pain, however, it significantly reduces the ability to modulate pain in a dose-response manner. Considering the diverse effects of stress in this and other studies, it appears that the type of stress and the magnitude of its appraisal determine its interactions with the pain system. Copyright © 2014 International Association for the Study of Pain. Published by Elsevier B.V. All rights reserved.
Pain education to prevent chronic low back pain: a study protocol for a randomised controlled trial.
Traeger, Adrian C; Moseley, G Lorimer; Hübscher, Markus; Lee, Hopin; Skinner, Ian W; Nicholas, Michael K; Henschke, Nicholas; Refshauge, Kathryn M; Blyth, Fiona M; Main, Chris J; Hush, Julia M; Pearce, Garry; McAuley, James H
2014-06-02
Low back pain (LBP) is the leading cause of disability worldwide. Of those patients who present to primary care with acute LBP, 40% continue to report symptoms 3 months later and develop chronic LBP. Although it is possible to identify these patients early, effective interventions to improve their outcomes are not available. This double-blind (participant/outcome assessor) randomised controlled trial will investigate the efficacy of a brief educational approach to prevent chronic LBP in 'at-risk' individuals. Participants will be recruited from primary care practices in the Sydney metropolitan area. To be eligible for inclusion participants will be aged 18-75 years, with acute LBP (<4 weeks' duration) preceded by at least a 1 month pain-free period and at-risk of developing chronic LBP. Potential participants with chronic spinal pain and those with suspected serious spinal pathology will be excluded. Eligible participants who agree to take part will be randomly allocated to receive 2×1 h sessions of pain biology education or 2×1 h sessions of sham education from a specially trained study physiotherapist. The study requires 101 participants per group to detect a 1-point difference in pain intensity 3 months after pain onset. Secondary outcomes include the incidence of chronic LBP, disability, pain intensity, depression, healthcare utilisation, pain attitudes and beliefs, global recovery and recurrence and are measured at 1 week post-intervention, and at 3, 6 and 12 months post LBP onset. Ethical approval was obtained from the University of New South Wales Human Ethics Committee in June 2013 (ref number HC12664). Outcomes will be disseminated through publication in peer-reviewed journals and presentations at international conference meetings. https://www.anzctr.org.au/Trial/Registration/TrialReview.aspx?ACTRN=12612001180808. Published by the BMJ Publishing Group Limited. For permission to use (where not already granted under a licence) please go
Effectiveness of Self-Hypnosis on the Relief of Experimental Dental Pain: A Randomized Trial.
Wolf, Thomas Gerhard; Wolf, Dominik; Below, Dagna; d'Hoedt, Bernd; Willershausen, Brita; Daubländer, Monika
2016-01-01
This randomized, controlled clinical trial evaluates the effectiveness of self-hypnosis on pain perception. Pain thresholds were measured, and a targeted, standardized pain stimulus was created by electrical stimulation of the dental pulp of an upper anterior tooth. Pain stimulus was rated by a visual analogue scale (VAS). The pain threshold under self-hypnosis was higher (57.1 ± 17.1) than without hypnotic intervention (39.5 ± 11.8) (p < .001). Pain was rated lower on the VAS with self-hypnosis (4.0 ± 3.8) than in the basal condition without self-hypnosis (7.1 ± 2.7) (p < .001). Self-hypnosis can be used in clinical practice as an adjunct to the gold standard of local anesthesia for pain management, as well as an alternative in individual cases.
McGregor, CIndy; Boyles, Robert; Murahashi, Laura; Sena, Tanya; Yarnall, Robert
2014-01-01
Objective: Posterior-to-anterior (PA) vertebral mobilization to the thoracic spine has been studied as an intervention for neck pain. Our purpose was to explore effects of a different mobilization technique, transverse vertebral pressure, on cervical range of motion (ROM) and pain when applied to the thoracic spine among participants with neck pain. Methods: A single-blinded quasi-experimental study with a one-group pretest–posttest design. A transverse group consisted of 21 participants whose neck pain increased with active movements. A non-intervention group of 20 asymptomatic participants was included simply to ensure rater blinding. The treatment group received Grades IV to IV+ transverse mobilizations at T1 through T4 bilaterally. Measurements taken immediately after intervention included pre/post cervical ROM, distant pressure pain threshold (PPT), and a numerical pain rating scale (NPRS). Analysis utilized t-tests and ordinal counterparts. Results: The transverse group demonstrated significant gains in extension and bilateral rotation (P≤0.005) but not flexion or side-bend. A total of 57% of mobilized participants reported clinically meaningful decreased pain (P<0.001). Seven participants exceeded the PPT MDC95 of 0.36 kg/cm2. The non-intervention group had no significant changes in ROM or NPRS scores. Discussion: After 8 minutes of transverse mobilization to the upper thoracic spine, significant gains in cervical extension and bilateral rotation, and decreased pain scores were found. There were no adverse effects. Unlike other mobilization studies, PPT changes at a remote site were statistically but not clinically meaningful. Findings suggest that transverse mobilization would be a productive topic for controlled clinical trials. PMID:25395827
Pain management in home hospice patients: A retrospective descriptive study.
Campbell, Cathy L; Kelly, Meghan; Rovnyak, Virginia
2017-09-01
The development and evaluation of evidence-based, safe, and effective home-based pain management models for caregivers implementation is receiving greater attention in the literature because of international initiatives intended to increase the number of people who receive end-of-life care in home-based settings. The purpose of this "retrospective descriptive design" study was to describe pharmacological pain management and outcomes for 40 cancer and non-cancer patients receiving hospice care at home. While the median pain score was higher at admission in the cancer group than in the hospice care at home group, the difference was not significant at or within 48 hour of admission. Overall, there was a significant decrease in pain from the first measurement to the second. Within the last seven days of life, the majority of participants were not able to provide a pain severity score when asked to evaluate the effectiveness of pain management, thus their caregiver provided a proxy evaluation. Pain management was effective in the home setting. More research is needed on the best methods to teach lay caregivers to assess pain and evaluate the effectiveness of pharmacological modalities to manage pain. © 2017 John Wiley & Sons Australia, Ltd.
Computer Simulation for Pain Management Education: A Pilot Study.
Allred, Kelly; Gerardi, Nicole
2017-10-01
Effective pain management is an elusive concept in acute care. Inadequate knowledge has been identified as a barrier to providing optimal pain management. This study aimed to determine student perceptions of an interactive computer simulation as a potential method for learning pain management, as a motivator to read and learn more about pain management, preference over traditional lecture, and its potential to change nursing practice. A post-computer simulation survey with a mixed-methods descriptive design was used in this study. A college of nursing in a large metropolitan university in the Southeast United States. A convenience sample of 30 nursing students in a Bachelor of Science nursing program. An interactive computer simulation was developed as a potential alternative method of teaching pain management to nursing students. Increases in educational gain as well as its potential to change practice were explored. Each participant was asked to complete a survey consisting of 10 standard 5-point Likert scale items and 5 open-ended questions. The survey was used to evaluate the students' perception of the simulation, specifically related to educational benefit, preference compared with traditional teaching methods, and perceived potential to change nursing practice. Data provided descriptive statistics for initial evaluation of the computer simulation. The responses on the survey suggest nursing students perceive the computer simulation to be entertaining, fun, educational, occasionally preferred over regular lecture, and with potential to change practice. Preliminary data support the use of computer simulation in educating nursing students about pain management. Copyright © 2017 American Society for Pain Management Nursing. Published by Elsevier Inc. All rights reserved.
Continuous neurophatic orofacial pain: A retrospective study of 23 cases.
Sotorra-Figuerola, Dídac; Sánchez-Torres, Alba; Valmaseda-Castellón, Eduard; Gay-Escoda, Cosme
2016-04-01
To determine the clinical characteristics of Continuous Neuropathic Orofacial Pain in patients that suffer Persistent Idiopathic Facial Pain (PIFP), Painful Post-Traumatic Trigeminal Neuropathy (PPTTN) or Burning Mouth Syndrome (BMS) and to describe their treatment. A retrospective observational study was made, reviewing the clinical history of the patients diagnosed with Continuous Neuropathic Orofacial Pain between 2004 and 2011 at the Orofacial Pain Unit of the Master of Oral Surgery and Implantology of the University of Barcelona and at the Orofacial Pain Unit of the Teknon Medical Center of Barcelona. The average age of the patients with Continuous Neuropathic Orofacial Pain was 54.5, with a clear female predominance (86.9%, n=20). Of all patients, 60.9% (n=14) were suffering a PIFP, 21.7% (n=5) had a BMS and 17.4% (n=4) were presenting a PPTTN. The pain quality described by the patients with Continuous Neuropathic Orofacial Pain was oppressive (43.47%, n=10), widely represented by patients with PIFP, and burning (39.13%, n=9) being the only quality that described patients with BMS. The treatment carried out with the patients was only pharmacologic. The most used drugs for the treatment of PIFP and PPTTN were clonazepam (50%, n=9) and amitriptyline (44.44%, n=8). However, a 55.5% (n=10) of the patients with PIFP or PPTTN required the association of two or more drugs for a correct pain control. All the patients with BMS responded satisfactorily to clonazepam. Continuous Neuropathic Orofacial Pain is a little known condition among the general population, physicians and dentists. This favors a late diagnosis and inaccurate treatments which entail unnecessary suffering. It is important to inform both the general population and health professionals concerning this painful condition. Continuous neuropathic orofacial pain, persistent idiopathic facial pain, painful post-traumatic trigeminal neuropathy, burning mouth syndrome, atypical odontalgia.
Sato, Junya; Mori, Megumi; Nihei, Satoru; Takeuchi, Satoshi; Kashiwaba, Masahiro; Kudo, Kenzo
2017-01-01
In an evaluation of chemotherapy-induced peripheral neuropathy (CIPN), objectivity may be poor because the evaluation is determined by the patient's subjective assessment. In such cases, management of neuropathy may be delayed and CIPN symptoms may become severe. In this pilot study, we attempted an objective evaluation of CIPN using a quantitative pain measurement system (Pain Vision ® ). The subjects were patients with gynecologic cancer who underwent chemotherapy using taxane and platinum drugs. The grade of the peripheral sensory nerve disorder was based on the Common Terminology Criteria for Adverse Events (CTC-AE) ver. 4.0 and was evaluated before the initiation of therapy and up to six chemotherapy cycles. A symptom scale assessed by the patients using a peripheral neuropathy questionnaire (PNQ) was also evaluated. Simultaneously during these evaluations, graded electric current was applied from the probe to a fingertip and measured both the lowest perceptible current and lowest current perceived as pain by Pain Vision ® . From these values, the pain degree was calculated from the following formula: (pain perception current value - lowest perceptible current value) ÷ lowest perceptible current value × 100. We compared the pain degrees by Pain Vision ® during CIPN development with the value obtained before chemotherapy initiation. Forty-one patients were enrolled. In the evaluation by a medical professional, 28 (64.3%) patients developed CIPN during 2.5 ± 1.1 chemotherapy cycles (mean ± standard deviation). The pain degree by Pain Vision ® at grade 1 and 2 CIPN development according to the evaluation (CTC-AE) was significantly decreased compared to that before chemotherapy initiation (126.0 ± 114.5 vs. 69.8 ± 46.8, p = 0.001, and 126.0 ± 114.5 vs. 32.8 ± 32.6, p = 0.004). Changes in the pain degree by Pain Vision ® were also found during scale B and C, D CIPN development in the patient evaluation (PNQ) (115.9 ± 112.4 vs. 70
Walters, Jenna L; Baxter, Kelly; Chapman, Hannah; Jackson, Tracy; Sethuramachandran, Adinarayanan; Couldridge, Marcus; Joshi, Hem Raj; Kundra, Pankaj; Liu, Xulei; Nair, Divya; Sullivan, Bonnie; Shotwell, Matthew S; Jense, Ryan J; Kassebaum, Nicholas J; McQueen, K A Kelly
2017-11-01
Evaluation and treatment of chronic pain worldwide are limited by the lack of standardized assessment tools incorporating consistent definitions of pain chronicity and specific queries of known social and psychological risk factors for chronic pain. The Vanderbilt Global Pain Survey (VGPS) was developed as a tool to address these concerns, specifically in the low- and middle-income countries where global burden is highest. The VGPS was developed using standardized and cross-culturally validated metrics, including the Brief Pain Inventory and World Health Organization Disability Assessment Scale, as well as the Pain Catastrophizing Scale, the Fibromyalgia Survey Questionnaire along with queries about pain attitudes to assess the prevalence of chronic pain and disability along with its psychosocial and emotional associations. The VGPS was piloted in both Nepal and India over a 1-month period in 2014, allowing for evaluation of this tool in 2 distinctly diverse cultures. Prevalence of chronic pain in Nepal and India was consistent with published data. The Nepali cohort displayed a pain point prevalence of 48%-50% along with some form of disability present in approximately one third of the past 30 days. Additionally, 11% of Nepalis recorded pain in 2 somatic sites and 39% of those surveyed documented a history of a traumatic event. In the Indian cohort, pain point prevalence was approximately 24% to 41% based on the question phrasing, and any form of disability was present in 6 of the last 30 days. Of the Indians surveyed, 11% reported pain in 2 somatic sites, with only 4% reporting a previous traumatic event. Overall, Nepal had significantly higher chronic pain prevalence, symptom severity, widespread pain, and self-reported previous traumatic events, yet lower reported pain severity. Our findings confirm prevalent chronic pain, while revealing pertinent cultural differences and survey limitations that will inform future assessment strategies. Specific areas for
Claes, Nathalie; Vlaeyen, Johan W S; Crombez, Geert
2016-09-01
Previous research shows that goal-directed behavior might be modulated by cues that predict (dis)similar outcomes. However, the literature investigating this modulation with pain outcomes is scarce. Therefore, this experiment investigated whether environmental cues predicting pain or reward modulate defensive pain responding. Forty-eight healthy participants completed a joystick movement task with two different movement orientations. Performing one movement was associated with a painful stimulus, whereas performance of another movement was associated with reward, i.e. lottery tickets. In a subsequent task, participants learned to associate three different cues withpain, reward, or neither of the two. Next, these cues were integrated in the movement task. This study demonstrates that in general, aversive cues enhance and appetitive cues reduce pain-related fear. Furthermore, we found that incongruence between the outcomes predicted by the movement and the cue results in more oscillatory behavior, i.e., participants were more willing to perform a painful movement when a cue predicting reward was simultaneously presented, and vice versa. Similarly, when given a choice, participants preferred to perform the reward movement, unless there was an incongruence between the outcomes predicted by the movements and cues. Taken together, these results provide experimental evidence that environmental cues are capable of modulating pain-related fear and avoidance behavior. Copyright © 2016 Elsevier Ltd. All rights reserved.
Referred knee pain in a young athlete: a case study.
Tippett, S R
1994-02-01
Parapatellar pain is a common complaint in the active adolescent patient population. Patello-femoral pain syndrome, Osgood-Schlatter disease, Sinding-Larsen-Johansson syndrome, patellar tendinitis, and other stress failure conditions are the primary causes of these parapatellar symptoms. Not all cases of knee discomfort are related to knee pathology. This case study discusses hip pathology as a source of referred knee pain in an 8-year-old male athlete. Care must be taken to evaluate all possible sources of both primary and referred pain in all cases.
Palmgren, Per J; Andreasson, Daniel; Eriksson, Magnus; Hägglund, Andreas
2009-01-01
Background Although cervical pain is widespread, most victims are only mildly and occasionally affected. A minority, however, suffer chronic pain and/or functional impairments. Although there is abundant literature regarding nontraumatic neck pain, little focuses on diagnostic criteria. During the last decade, research on neck pain has been designed to evaluate underlying pathophysiological mechanisms, without noteworthy success. Independent researchers have investigated postural balance and cervicocephalic kinesthetic sensibility among patients with chronic neck pain, and have (in most cases) concluded the source of the problem is a reduced ability in the neck's proprioceptive system. Here, we investigated cervicocephalic kinesthetic sensibility and postural balance among patients with nontraumatic chronic neck pain. Methods Ours was a two-group, observational pilot study of patients with complaints of continuous neck pain during the 3 months prior to recruitment. Thirteen patients with chronic neck pain of nontraumatic origin were recruited from an institutional outpatient clinic. Sixteen healthy persons were recruited as a control group. Cervicocephalic kinesthetic sensibility was assessed by exploring head repositioning accuracy and postural balance was measured with computerized static posturography. Results Parameters of cervicocephalic kinesthetic sensibility were not reduced. However, in one of six test movements (flexion), global repositioning errors were significantly larger in the experimental group than in the control group (p < .05). Measurements did not demonstrate any general impaired postural balance, and varied substantially among participants in both groups. Conclusion In patients with nontraumatic chronic neck pain, we found statistically significant global repositioning errors in only one of six test movements. In this cohort, we found no evidence of impaired postural balance. Head repositioning accuracy and computerized static posturography are
Lehmkuhl, D; Meissner, W; Neugebauer, E A M
2011-09-01
Demonstration of improved postoperative pain management by implementation of the S3 guidelines on treatment of acute perioperative and posttraumatic pain, by the integrated quality management concept "quality management acute pain" of the TÜV Rheinland or by participation in the benchmark project "Quality improvement in postoperative pain management" (QUIPS). A prospective controlled study (pre-post design) was carried out in hospitals with various levels of care comparing three hospital groups (n = 17/7/3, respectively). Group 1: participation in the QUIPS project (intraclinic and interclinic comparison of outcome data of postoperative pain treatment), group 2: participation in the quality management acute pain program (certified by TÜV Rheinland), group 3: control group with no involvement in either of the two concepts. In all three groups, an anonymous data collection was performed consisting of patient-reported pain intensity, side effects, pain disability and patient satisfaction. Pain therapy intervention was carried out only in group 2 by an integrated quality management concept (certification project: Quality management acute pain) with a package of measures to improve structure, process and outcome quality. The TÜV Rheinland certified clinics (group 2) showed a significant improvement in the pre-post comparison (before versus after certification) in the areas maximum pain (from visual analogue scale VAS 4.6 to 3.7), stress pain (5.3 to 3.9), pain-related impairment (proportion of patients with pain-linked decreased mobility and movement 26% to 16.1%, coughing and breathing 23.1% to 14.3%) and patient satisfaction (from 13.2 to 13.7; scale 0 completely unsatisfied, 15 very satisfied). The clinics with participation in QUIPS for 2 years also showed a significant improvement in stress pain (numeric rating scale NRS for pain 4.5 to 4.2), pain-linked-limitation of coughing and breathing (28% to 23.6%), and patient satisfaction (from 11.9 to 12.4). There were
Dancing in pain: pain appraisal and coping in dancers.
Anderson, Ruth; Hanrahan, Stephanie J
2008-01-01
This study investigated the relationships between the type of pain experienced (performance pain and injury pain), the cognitive appraisal of pain and pain coping styles in dancers. Fifty-one professional ballet and contemporary dancers (17 males and 34 females), with the mean age of 25.9 years, completed a general pain questionnaire, the Pain Appraisal Inventory, the Survey of Pain Attitudes Control Subscale, and the Sports Inventory for Pain. Multivariate analyses of variance indicated that both the cognitive appraisal of the pain and pain coping styles did not differ according to the type of pain experienced or the pain severity. However, it was found that dancers with performance pain of either low or high severity were more likely to dance in pain than dancers experiencing injury pain. Multiple regression analyses indicated that the appraisal of pain as threatening was predictive of the use of avoidance and catastrophizing pain coping styles. Overall, results indicated that dancers may not differentiate between performance pain and injury pain, or modify their appraisal and coping strategies according to the characteristics of the pain experienced. The study highlighted an opportunity for increased education for dancers in recognizing the difference between pain considered to be a routine aspect of training and pain which is a signal of serious injury.
Vervoort, Tine; Caes, Line; Crombez, Geert; Koster, Ernst; Van Damme, Stefaan; Dewitte, Marieke; Goubert, Liesbet
2011-08-01
The attentional demand of pain has primarily been investigated within an intrapersonal context. Little is known about observers' attentional processing of another's pain. The present study investigated, within a sample of parents (n=65; 51 mothers, 14 fathers) of school children, parental selective attention to children's facial display of pain and the moderating role of child's facial expressiveness of pain and parental catastrophizing about their child's pain. Parents performed a dot-probe task in which child facial display of pain (of varying pain expressiveness) were presented. Findings provided evidence of parental selective attention to child pain displays. Low facial displays of pain appeared sufficiently and also, as compared with higher facial displays of pain, equally capable of engaging parents' attention to the location of threat. Severity of facial displays of pain had a nonspatial effect on attention; that is, there was increased interference (ie, delayed responding) with increasing facial expressiveness. This interference effect was particularly pronounced for high-catastrophizing parents, suggesting that being confronted with increasing child pain displays becomes particularly demanding for high-catastrophizing parents. Finally, parents with higher levels of catastrophizing increasingly attended away from low pain expressions, whereas selective attention to high-pain expressions did not differ between high-catastrophizing and low-catastrophizing parents. Theoretical implications and further research directions are discussed. Copyright © 2011 International Association for the Study of Pain. Published by Elsevier B.V. All rights reserved.
Zeidan, F.; Grant, J.A.; Brown, C.A.; McHaffie, J.G.; Coghill, R.C.
2013-01-01
The cognitive modulation of pain is influenced by a number of factors ranging from attention, beliefs, conditioning, expectations, mood, and the regulation of emotional responses to noxious sensory events. Recently, mindfulness meditation has been found attenuate pain through some of these mechanisms including enhanced cognitive and emotional control, as well as altering the contextual evaluation of sensory events. This review discusses the brain mechanisms involved in mindfulness meditation-related pain relief across different meditative techniques, expertise and training levels, experimental procedures, and neuroimaging methodologies. Converging lines of neuroimaging evidence reveal that mindfulness meditation-related pain relief is associated with unique appraisal cognitive processes depending on expertise level and meditation tradition. Moreover, it is postulated that mindfulness meditation-related pain relief may share a common final pathway with other cognitive techniques in the modulation of pain. PMID:22487846
Degenhardt, Louisa; Lintzeris, Nicholas; Campbell, Gabrielle; Bruno, Raimondo; Cohen, Milton; Farrell, Michael; Hall, Wayne D
2015-02-01
There is increasing debate about cannabis use for medical purposes, including for symptomatic treatment of chronic pain. We investigated patterns and correlates of cannabis use in a large community sample of people who had been prescribed opioids for chronic non-cancer pain. The POINT study included 1514 people in Australia who had been prescribed pharmaceutical opioids for chronic non-cancer pain. Data on cannabis use, ICD-10 cannabis use disorder and cannabis use for pain were collected. We explored associations between demographic, pain and other patient characteristics and cannabis use for pain. One in six (16%) had used cannabis for pain relief, 6% in the previous month. A quarter reported that they would use it for pain relief if they had access. Those using cannabis for pain on average were younger, reported greater pain severity, greater interference from and poorer coping with pain, and more days out of role in the past year. They had been prescribed opioids for longer, were on higher opioid doses, and were more likely to be non-adherent with their opioid use. Those using cannabis for pain had higher pain interference after controlling for reported pain severity. Almost half (43%) of the sample had ever used cannabis for recreational purposes, and 12% of the entire cohort met criteria for an ICD-10 cannabis use disorder. Cannabis use for pain relief purposes appears common among people living with chronic non-cancer pain, and users report greater pain relief in combination with opioids than when opioids are used alone. Copyright © 2014 Elsevier Ireland Ltd. All rights reserved.
A Pilot Study of Mindfulness Meditation for Pediatric Chronic Pain
Waelde, Lynn C.; Feinstein, Amanda B.; Bhandari, Rashmi; Griffin, Anya; Yoon, Isabel A.; Golianu, Brenda
2017-01-01
Despite advances in psychological interventions for pediatric chronic pain, there has been little research examining mindfulness meditation for these conditions. This study presents data from a pilot clinical trial of a six-week manualized mindfulness meditation intervention offered to 20 adolescents aged 13–17 years. Measures of pain intensity, functional disability, depression and parent worry about their child’s pain were obtained at baseline and post-treatment. Results indicated no significant changes in pain or depression, however functional disability and frequency of pain functioning complaints improved with small effect sizes. Parents’ worry about child’s pain significantly decreased with a large effect size. Participants rated intervention components positively and most teens suggested that the number of sessions be increased. Three case examples illustrate mindfulness meditation effects and precautions. Mindfulness meditation shows promise as a feasible and acceptable intervention for youth with chronic pain. Future research should optimize intervention components and determine treatment efficacy. PMID:28445406
Prevalence of pain among residents in Japanese nursing homes: a descriptive study.
Takai, Yukari; Yamamoto-Mitani, Noriko; Chiba, Yumi; Nishikawa, Yuri; Sugai, Yuichi; Hayashi, Kunihiko
2013-06-01
It is often observed that pain causes substantial problems for nursing home residents. However, there has been little research about the prevalence of pain for nursing home residents in Japan. This study aimed to examine the prevalence of pain in older adults living in nursing homes in Japan by using self-reporting and the Abbey Pain Scale-Japanese version (APS-J) and to explore factors related to pain. This is a descriptive study. Residents in two Special Nursing Homes for the Elderly in Tokyo, Japan, were asked to participate in this study, with the exclusion of short-term temporary residents. Data collected from participating residents included their demographics and the results from the Barthel Index, the Folstein Mini-Mental State Examination, the APS-J, and the Verbal Descriptor Scale for pain. The residents were divided into two groups: residents able to report their pain (self-report group) and residents not able to report their pain. The second group was assessed by using the APS-J (APS-J group). The Mann-Whitney U test, the χ2 test, and logistic analyses were performed to derive factors related to pain prevalence. Data were obtained from 171 residents. The prevalence of pain in the self-report group (n = 96) was 41.7%. For the 75 residents unable to report their pain, 52.0% were assessed by the APS-J to have pain. The overall pain prevalence of all residents was 46.2%. Age, Barthel Index score, and length of time of institutionalization were significantly associated with residents' pain in the APS-J group. Logistic regression analysis showed that contracture (odds ratio 3.8) and previous injury (odds ratio 3.4) were associated with residents' pain in the self-report group, whereas only the length of nursing home stay (odds ratio 1.03) was a predictor for pain in the APS-J group. Nearly one-half of residents had pain when they moved or were moved. Pain assessment and management is needed for residents. Copyright © 2013 American Society for Pain
Hsieh, Yi-Chuan; Cheng, Su-Fen; Tsay, Pei-Kwei; Su, Wen-Jen; Cho, Yen-Hua; Chen, Chi-Wen
2017-12-01
This study aimed to evaluate the effects of cognitive-behavioral program on pain and medical fear in hospitalized school-aged children receiving intravenous (IV) placement. This study used an quasi-experimental design. Thirty-five participants were assigned to the experimental group and 33 to the control group in the acute internal medicine ward of a children's hospital. The cognitive-behavioral program entailed having the patients read an educational photo book about IV placement before the procedure and having them watch their favorite music video during the procedure. The outcome measures were numeric rating scales for pain intensity and fear during the procedure. After applying the cognitive-behavioral program, the mean scores on pain and fear decreased in the experimental group. However, the difference in pain intensity between these two groups was nonsignificant. The intensity of fear in the experimental group was significantly lower than that in the control group. In this study, the cognitive-behavioral program used with school-aged hospitalized children promoted less fear during IV placement. The results of this study can serve as a reference for empirical nursing care and as care guidance for clinical IV injections involving children. Copyright © 2017. Published by Elsevier B.V.
Painful Temporomandibular Disorder: Decade of Discovery from OPPERA Studies.
Slade, G D; Ohrbach, R; Greenspan, J D; Fillingim, R B; Bair, E; Sanders, A E; Dubner, R; Diatchenko, L; Meloto, C B; Smith, S; Maixner, W
2016-09-01
In 2006, the OPPERA project (Orofacial Pain: Prospective Evaluation and Risk Assessment) set out to identify risk factors for development of painful temporomandibular disorder (TMD). A decade later, this review summarizes its key findings. At 4 US study sites, OPPERA recruited and examined 3,258 community-based TMD-free adults assessing genetic and phenotypic measures of biological, psychosocial, clinical, and health status characteristics. During follow-up, 4% of participants per annum developed clinically verified TMD, although that was a "symptom iceberg" when compared with the 19% annual rate of facial pain symptoms. The most influential predictors of clinical TMD were simple checklists of comorbid health conditions and nonpainful orofacial symptoms. Self-reports of jaw parafunction were markedly stronger predictors than corresponding examiner assessments. The strongest psychosocial predictor was frequency of somatic symptoms, although not somatic reactivity. Pressure pain thresholds measured at cranial sites only weakly predicted incident TMD yet were strongly associated with chronic TMD, cross-sectionally, in OPPERA's separate case-control study. The puzzle was resolved in OPPERA's nested case-control study where repeated measures of pressure pain thresholds revealed fluctuation that coincided with TMD's onset, persistence, and recovery but did not predict its incidence. The nested case-control study likewise furnished novel evidence that deteriorating sleep quality predicted TMD incidence. Three hundred genes were investigated, implicating 6 single-nucleotide polymorphisms (SNPs) as risk factors for chronic TMD, while another 6 SNPs were associated with intermediate phenotypes for TMD. One study identified a serotonergic pathway in which multiple SNPs influenced risk of chronic TMD. Two other studies investigating gene-environment interactions found that effects of stress on pain were modified by variation in the gene encoding catechol O
Children’s Forgetting of Pain-Related Memories
Briere, Jennifer L.; von Baeyer, Carl L.
2016-01-01
Objective Given that forgetting negative experiences can help children cope with these experiences, we examined their ability to forget negative aspects of painful events. Methods 86 children aged 7–15 years participated in a retrieval-induced forgetting task whereby they repeatedly retrieved positive details of a physically painful experience, and an experimental pain task (cold-pressor task). Results Repeatedly retrieving positive details of a prior pain experience produced forgetting of the negative aspects of that experience. Pain-related self-efficacy predicted retrieval-induced forgetting; children with a poorer belief in their ability to cope with pain experienced less forgetting. Children who had a more difficult time forgetting prior negative experiences were more anxious about the pain task and reported higher pain thresholds. Conclusions Understanding children’s memory for painful experiences may help improve their pain management and coping ability. PMID:26666267
Fletcher, Claire; Bradnam, Lynley; Barr, Christopher
2016-05-01
Chronic pain is prevalent in the western world; however fear of pain often has a greater impact than the degree of initial injury. The aim of this study was to explore the relationship between knowledge of the neurophysiology of pain and fear avoidance in individuals diagnosed with chronic pain. Twenty-nine people with chronic musculoskeletal pain were recruited and completed questionnaires to determine their understanding of pain neurophysiology and the degree of their fear avoidance beliefs. There was an inverse relationship between knowledge of pain neurophysiology and the level of fear avoidance. Patients with higher pain knowledge reported less fear avoidance and lower perceived disability due to pain. There was no relationship with the educational level or compensable status for either variable. The findings suggest that fear avoidance is positively influenced by neurophysiology of pain education, so that a higher level of pain knowledge is associated with less activity-related fear. The clinical implication is that reducing fear avoidance/kinesiophobia using neurophysiology of pain education in people with chronic pain may provide an effective strategy to help manage fear avoidance and related disability in the chronic pain population in order to improve treatment outcomes.
Valencia, Carolina; Kindler, Lindsay L.; Fillingim, Roger B.; George, Steven Z.
2011-01-01
Recent reports suggest deficits in conditioned pain modulation (CPM) and enhanced suprathreshold heat pain response (SHPR) potentially play a role in the development of chronic pain. The purpose of this study was to investigate whether central pain processing was altered in 2 musculoskeletal shoulder pain models. The goals of this study were to determine whether central pain processing: 1) differs between healthy subjects and patients with clinical shoulder pain, 2) changes with induction of exercise induced muscle pain (EIMP), and 3) changes 3 months after shoulder surgery. Fifty eight patients with clinical shoulder pain and 56 age and sex matched healthy subjects were included in these analyses. The healthy cohort was examined before inducing EIMP, and 48 and 96 hours later. The clinical cohort was examined before shoulder surgery and 3 months later. CPM did not differ between the cohorts, however; SHPR was elevated for patients with shoulder pain compared to healthy controls. Induction of acute shoulder pain with EIMP resulted in increased shoulder pain intensity but did not change CPM or SHPR. Three months following shoulder surgery clinical pain intensity decreased but CPM was unchanged from pre-operative assessment. In contrast SHPR was decreased and showed values comparable with healthy controls at 3 months. Therefore, the present study suggests that: 1) clinical shoulder pain is associated with measurable changes in central pain processing, 2) exercise-induced shoulder pain did not affect measures of central pain processing, and 3) elevated SHPR was normalized with shoulder surgery. Collectively our findings support neuroplastic changes in pain modulation were associated with decreases in clinical pain intensity only, and could be detected more readily with thermal stimuli. PMID:22208804
Goyal, Nitin; McKenzie, James; Sharkey, Peter F; Parvizi, Javad; Hozack, William J; Austin, Matthew S
2013-01-01
Postoperative pain after total knee arthroplasty remains one of the most important challenges facing patients undergoing this surgery. Providing a balance of adequate analgesia while limiting the functional impact of regional anesthesia and minimizing opioid side effects is critical to minimize adverse events and improve patient satisfaction. We asked whether bupivacaine delivered through an elastomeric device decreases the (1) patients' perception of pain after TKA; (2) narcotic consumption; and (3) narcotic-related side effects as compared with a placebo. In this prospective, double-blind, placebo-controlled study, all patients received standardized regional anesthesia, a preemptive and multimodal analgesic protocol, and a continuous intraarticular infusion at 5 mL/hour through an elastomeric infusion pump. The patients were randomized to receive either an infusion pump filled with (1) 300 mL of 0.5% bupivacaine, the experimental group (n = 75); or (2) 300 mL of 0.9% normal saline solution, the control group (n = 75). Data concerning postoperative pain levels through a visual analog scale, postoperative opioid consumption, opioid-related side effects, and complications were collected and analyzed. Patients in the experimental group receiving the bupivacaine reported a reduction in pain levels in highest, lowest, and current visual analog scale scores compared with the placebo group on the first postoperative day and highest visual analog scale score on postoperative Day 2 along with a 33% reduction in opioid consumption on postoperative Day 2 and a 54% reduction on postoperative Day 3. In patients undergoing TKA, continuous intraarticular analgesia provided an effective adjunct for pain relief in the immediate postoperative period without the disadvantages encountered with other analgesic methods.
Effects of intravenous propranolol on heat pain sensitivity in healthy men.
Schweinhardt, P; Abulhasan, Y B; Koeva, V; Balderi, T; Kim, D J; Alhujairi, M; Carli, F
2013-05-01
Clinical studies have shown opioid-sparing effects of β-adrenergic antagonists perioperatively and β-blockers are being investigated for chronic musculoskeletal pain. However, the direct analgesic effects of β-blockers have rarely been examined in healthy humans. In a randomized, counter-balanced, double-blind, within-subject crossover design, we tested the effect of the lipophilic β-blocker propranolol (0.035 mg/kg body weight i.v.) on heat pain sensitivity in 39 healthy males, compared with placebo. To test for peripheral versus central effects, the peripherally acting β-blocker sotalol was also examined. Experimental stimuli were brief superficial noxious heat stimuli applied to the volar forearm. Non-painful cold stimuli were included to test for specificity. Sedation, mood and anxiety were assessed to investigate potential mechanisms underlying any analgesic effect. β-blocker effects on blood pressure were incorporated into the analysis because of a known inverse relationship between pain sensitivity and systolic blood pressure. Propranolol significantly decreased perceived intensity of heat pain stimuli but only in participants with small propranolol-induced blood pressure decreases. Even in this group, the effect was small (4%). Propranolol did not influence perceived intensity of non-noxious stimuli and had no effect on sedation, anxiety or mood. Sotalol did not influence heat pain sensitivity. Propranolol decreased pain sensitivity but its analgesic effects were small and counteracted by blood pressure decreases. The analgesic effects were not mediated by peripheral β-receptor blockade, sedation, mood or anxiety. The small effect indicates that the utility of β-blockers for clinical pain must be related to factors that do not play a significant role for experimental pain. © 2012 European Federation of International Association for the Study of Pain Chapters.
Dowman, Robert; Ritz, Benjamin; Fowler, Kathleen
2016-08-01
Connectionist modeling was used to investigate the brain mechanisms responsible for pain's ability to shift attention away from another stimulus modality and toward itself. Different connectionist model architectures were used to simulate the different possible brain mechanisms underlying this attentional bias, where nodes in the model simulated the brain areas thought to mediate the attentional bias, and the connections between the nodes simulated the interactions between the brain areas. Mathematical optimization techniques were used to find the model parameters, such as connection strengths, that produced the best quantitative fits of reaction time and event-related potential data obtained in our previous work. Of the several architectures tested, two produced excellent quantitative fits of the experimental data. One involved an unexpected pain stimulus activating somatic threat detectors in the dorsal posterior insula. This threat detector activity was monitored by the medial prefrontal cortex, which in turn evoked a phasic response in the locus coeruleus. The locus coeruleus phasic response resulted in a facilitation of the cortical areas involved in decision and response processes time-locked to the painful stimulus. The second architecture involved the presence of pain causing an increase in general arousal. The increase in arousal was mediated by locus coeruleus tonic activity, which facilitated responses in the cortical areas mediating the sensory, decision, and response processes involved in the task. These two neural network architectures generated competing predictions that can be tested in future studies.
Predictors of Low Back Pain Onset in a Prospective British Study
Power, Chris; Frank, John; Hertzman, Clyde; Schierhout, Gill; Li, Leah
2001-01-01
Objectives. This study examined predictors of low back pain onset in a British birth cohort. Methods. Univariate and multivariate analyses focused on individuals who experienced onset of low back pain at 32 to 33 years of age (n= 571) and individuals who were pain free (n = 5210). Participants were members of the 1958 British birth cohort. Results. Incident pain was elevated among those with psychological distress at 23 years of age (adjusted odds ratio [OR] = 2.52, 95% confidence interval [CI] = 1.65, 3.86) and among persistent moderate or heavy smokers (adjusted OR = 1.63, 95% CI = 1.23, 2.17). Significant univariate associations involving other factors (e.g., social class, childhood emotional status, body mass index, job satisfaction) did not persist in multivariate analyses. Conclusions. This prospectively studied cohort provides evidence that psychological distress more than doubles later risk of low back pain, with smoking having a modest independent effect. Other prospective studies are needed to confirm these findings before implications for low back pain prevention can be assessed. PMID:11574334
Yamada, Keiko; Wakaizumi, Kenta; Fukai, Kyosuke; Iso, Hiroyasu; Sobue, Tomotaka; Shibata, Masahiko; Matsudaira, Ko
2017-10-05
This study was performed to identify the prevalence, influence, and risk factors associated with chronic pain among Japanese industry workers. We investigated 2,544 participants working at a manufacturing company A, a manufacturing company B, and 16 branch shops of a retail chain company C. The participants responded to self-administered questionnaires related to pain. Furthermore, data obtained from the lifestyle interview sheet of an annual health screening examination and those obtained from the questionnaires were merged. We analyzed the association between lifestyles, psychosocial factors, and chronic pain. Age- and sex-adjusted odds ratios were calculated with a 95% confidence interval using the logistic regression model. Of 2,544 participants, 1,914 (1,224 men and 690 women) completed the questionnaire, and the response rate was 75.2%. The prevalence of chronic pain over 3 months was 42.7% and that of chronic pain with work disability was 11.3%. A higher proportion of obesity, smoking habit, insomnia, psychological stress, depressive state, workaholic nature, low social support from supervisors and coworkers, high job demand, low job control, and job dissatisfaction was observed in workers with chronic pain than in workers without pain. Several risk factors of chronic pain in Japanese industry workers were found. Obesity, smoking habits, sleep disorders, workplace environment, and mental state should be taken into account as risk factors associated with chronic pain issues and general occupational health.
Attentional processing of other's facial display of pain: an eye tracking study.
Vervoort, Tine; Trost, Zina; Prkachin, Kenneth M; Mueller, Sven C
2013-06-01
The present study investigated the role of observer pain catastrophizing and personal pain experience as possible moderators of attention to varying levels of facial pain expression in others. Eye movements were recorded as a direct and continuous index of attention allocation in a sample of 35 undergraduate students while viewing slides presenting picture pairs consisting of a neutral face combined with either a low, moderate, or high expressive pain face. Initial orienting of attention was measured as latency and duration of first fixation to 1 of 2 target images (i.e., neutral face vs pain face). Attentional maintenance was measured by gaze duration. With respect to initial orienting to pain, findings indicated that participants reporting low catastrophizing directed their attention more quickly to pain faces than to neutral faces, with fixation becoming increasingly faster with increasing levels of facial pain expression. In comparison, participants reporting high levels of catastrophizing showed decreased tendency to initially orient to pain faces, fixating equally quickly on neutral and pain faces. Duration of the first fixation revealed no significant effects. With respect to attentional maintenance, participants reporting high catastrophizing and pain intensity demonstrated significantly longer gaze duration for all face types (neutral and pain expression), relative to low catastrophizing counterparts. Finally, independent of catastrophizing, higher reported pain intensity contributed to decreased attentional maintenance to pain faces vs neutral faces. Theoretical implications and further research directions are discussed. Copyright © 2013 International Association for the Study of Pain. Published by Elsevier B.V. All rights reserved.
Feasibility study of Transcutaneous Electrical Nerve Stimulation (TENS) for cancer bone pain.
Bennett, Michael I; Johnson, Mark I; Brown, Sarah R; Radford, Helen; Brown, Julia M; Searle, Robert D
2010-04-01
This multicenter study assessed the feasibility of conducting a phase III trial of transcutaneous electrical nerve stimulation (TENS) in patients with cancer bone pain recruited from palliative care services. Eligible patients received active and placebo TENS for 1 hour at site of pain in a randomized crossover design; median interval between applications 3 days. Responses assessed at 30 and 60 minutes included numerical and verbal ratings of pain at rest and on movement, and pain relief. Recruitment, tolerability, adverse events, and effectiveness of blinding were also evaluated. Twenty-four patients were randomised and 19 completed both applications. The intervention was well tolerated. Five patients withdrew: 3 due to deteriorating performance status, and 2 due to increased pain (1 each following active and placebo TENS). Confidence interval estimation around the differences in outcomes between active and placebo TENS suggests that TENS has the potential to decrease pain on movement more than pain on rest. Nine patients did not consider that a placebo was used; the remaining 10 correctly identified placebo TENS. Feasibility studies are important in palliative care prior to undertaking clinical trials. Our findings suggest that further work is required on recruitment strategies and refining the control arm before evaluating TENS in cancer bone pain. Cancer bone pain is common and severe, and partly mediated by hyperexcitability. Animal studies suggest that Transcutaneous Electrical Nerve Stimulation can reduce hyperalgesia. This study examined the feasibility of evaluating TENS in patients with cancer bone pain in order to optimize methods before a phase III trial. Copyright 2010 American Pain Society. Published by Elsevier Inc. All rights reserved.
Menopause affects pain depending on pain type and characteristics.
Meriggiola, Maria Cristina; Nanni, Michela; Bachiocco, Valeria; Vodo, Stellina; Aloisi, Anna M
2012-05-01
Women are more affected than men by many chronic pain conditions, suggesting the effect of sex-related mechanisms in their occurrence. The role of gonadal hormones has been studied but with contrasting results depending on the pain syndrome, reproductive status, and hormone considered. The aim of the present study was to evaluate the pain changes related to the menopausal transition period. In this observational study, postmenopausal women were asked to evaluate the presence of pain in their life during the premenopausal and postmenopausal periods and its modification with menopause. One hundred one women were enrolled and completed questionnaires on their sociodemographic status, pain characteristics, and evolution. The most common pain syndromes were headache (38%), osteoarticular pain (31%), and cervical/lumbar pain (21%). Pain was present before menopause in 66 women, ceased with menopause in 17, and started after menopause in 18. Data were used for cluster analysis, which allowed the division of participants into four groups. In the first, all women experienced headaches that disappeared or improved with menopause. The second group included osteoarticular pain; the pain improved in half of these women and remained stable in the other half. The third group had cervical/lumbar pain, which disappeared or improved with menopause in all. The fourth group presented different kinds of moderate pain, which worsened in all. The present study provides preliminary data suggesting that menopause can affect pain depending on the painful condition experienced by the woman. This underlines the different interactions of menopause-related events with body structures involved in pain.