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Sample records for experimental pain study

  1. Heritability of pain catastrophizing and associations with experimental pain outcomes: a twin study.

    PubMed

    Trost, Zina; Strachan, Eric; Sullivan, Michael; Vervoort, Tine; Avery, Ally R; Afari, Niloofar

    2015-03-01

    This study used a twin paradigm to examine genetic and environmental contributions to pain catastrophizing and 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, which suggests 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

  2. Heritability of pain catastrophizing and associations with experimental pain outcomes: a twin study.

    PubMed

    Trost, Zina; Strachan, Eric; Sullivan, Michael; Vervoort, Tine; Avery, Ally R; Afari, Niloofar

    2015-03-01

    This study used a twin paradigm to examine genetic and environmental contributions to pain catastrophizing and 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, which suggests 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.

  3. Heritability of Pain Catastrophizing and Associations with Experimental Pain Outcomes: A Twin Study

    PubMed Central

    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

  4. Decreased pain sensitivity among people with schizophrenia: a meta-analysis of experimental pain induction studies.

    PubMed

    Stubbs, Brendon; Thompson, Trevor; Acaster, Sarah; Vancampfort, Davy; Gaughran, Fiona; Correll, Christoph U

    2015-11-01

    Patients with schizophrenia report reduced pain sensitivity in clinical studies, but experimental studies are required to establish pain sensitivity as a potential endophenotype. We conducted a systematic review of electronic databases from database inception until April 15, 2015, including experimental studies investigating pain among patients with schizophrenia spectrum disorder vs healthy controls. A random-effect meta-analysis yielding Hedges' g ±95% confidence intervals (CIs) as the effect size (ES) measure was conducted. Primary outcome was a pooled composite of pain threshold and pain tolerance; secondary outcomes included these parameters individually, plus sensory threshold, physiological pain response, and pain intensity or unpleasantness. Across 17 studies, patients with schizophrenia spectrum disorder (n = 387; age, 30.7 ± 6.9 years; females, 31.9%; illness duration, 7.0 ± 5.7 years) were compared with controls (n = 483; age, 29.5 ± 7.4 years; females, 31.0%). Patients had elevated pain threshold/pain tolerance vs controls (ES = 0.583; 95% CI, 0.212-0.954; P = 0.002; studies = 15). Results were similar in antipsychotic-free individuals (ES = 0.599; 95% CI, 0.291-0.907; P < 0.0001; studies = 8), with trend-level significance in antipsychotic-treated individuals (ES = 0.566; 95% CI, -0.007 to 1.125; P = 0.047; studies = 9). Likewise, patients with schizophrenia had increased pain tolerance (ES = 0.566; 95% CI, 0.235-0.897; P = 0.0001; studies = 6), sensory threshold (ES = 1.16; 95% CI, 0.505-1.727; P < 0.0001; studies = 5), and pain threshold (ES = 0.696; 95% CI, 0.407-0.986; P < 0.001; studies = 9), as well as reduced physiological response to noxious stimuli (ES = 0.456; 95% CI, 0.131-0.783; P = 0.006) and pain intensity/unpleasantness ratings (ES = 0.547; 95% CI, 0.146-0.949; P = 0.008). Findings were similarly significant in antipsychotic-free patients with schizophrenia (analysable parameters = 4) and antipsychotic-treated individuals (analysable

  5. Muscle pain: animal and human experimental and clinical studies.

    PubMed

    Marchettini, P

    1993-10-01

    The search for the identification of the sensory apparatus encoding muscle pain sensation in humans is recounted. Basic neurophysiologic animal studies, leading to a description of slowly conducting afferent from muscle and definition of high threshold polymodal muscle nociceptors, and pioneer psychophysic human studies together with recent microneurographic experiments in humans are described. The phenomena of muscle pain broad localization and distant referral are discussed, and clinical implications are extrapolated to interpret muscle pain as a localizing sign of mononeuropathy or radiculopathy. The identification of human muscle nociceptors has defined the scientific standard to test emerging clinical descriptions having muscle pain as a symptom.

  6. The effects of slow breathing on affective responses to pain stimuli: an experimental study.

    PubMed

    Zautra, Alex J; Fasman, Robert; Davis, Mary C; Craig, Arthur D Bud

    2010-04-01

    This study examined whether breathing rate affected self-reported pain and emotion following thermal pain stimuli in women with fibromyalgia syndrome (FM: n=27) or age-matched healthy control women (HC: n=25). FM and HC were exposed to low and moderate thermal pain pulses during paced breathing at their normal rate and one-half their normal rate. Thermal pain pulses were presented in four blocks of four trials. Each block included exposure to both mild and moderate pain trials, and periods of both normal and slow paced breathing. Pain intensity and unpleasantness were recorded immediately following each pain trial, and positive and negative affect were assessed at the end of each block of trials. Compared to normal breathing, slow breathing reduced ratings of pain intensity and unpleasantness, particularly for moderately versus mildly painful thermal stimuli. The effects of slow breathing on pain ratings were less reliable for FM patients than for HCs. Slow versus normal breathing decreased negative affect ratings following thermal pain pulses for both groups, and increased positive affect reports, but only for healthy controls with high trait negative affect. Participants who reported higher levels of trait positive affect prior to the experiment showed greater decreases in negative affect as a result of slow versus normal breathing. These experimental findings provide support for prior reports on the benefits of yogic breathing and mindful Zen meditation for pain and depressed affect. However, chronic pain patients may require more guidance to obtain therapeutic benefit from reduced breathing rates.

  7. Assessing experimental visceral pain in dairy cattle: A pilot, prospective, blinded, randomized, and controlled study focusing on spinal pain proteomics.

    PubMed

    Rialland, P; Otis, C; de Courval, M-L; Mulon, P-Y; Harvey, D; Bichot, S; Gauvin, D; Livingston, A; Beaudry, F; Hélie, P; Frank, D; Del Castillo, J R E; Troncy, E

    2014-01-01

    Few studies have verified the validity of behavioral and physiological methods of pain assessment in cattle. This prospective, blinded, randomized controlled experimental study aimed to validate different methods of pain assessment during acute and chronic (up to 21 d postintervention) conditions in dairy cattle, in response to 3 analgesic treatments for traumatic reticuloperitonitis. Cerebrospinal fluid (CSF) biomarkers and mechanical sensitization were measured as indicators of centralized pain. Proteomics in the CSF were examined to detect specific (to pain intensity) and sensitive (responsive to analgesia) markers. Recordings of spontaneous behavior with video analysis, telemetered motor activity, pain scales, electrodermal activity, and plasma cortisol concentration were quantified at regular intervals. Cows were assigned to group 1 (n=4, standard control receiving aspirin), group 2 (n=5, test group receiving preemptive tolfenamic acid), or group 3 (n=3, positive control receiving preemptive multimodal analgesia composed of epidural morphine, plus tolfenamic acid and butorphanol). Rescue analgesia was administered as needed. Generalized estimating equations tested group differences and the influence of rescue analgesia on the measurements. All 3 groups demonstrated a long-term decrease in a CSF protein identified as transthyretin. The decrease in transthyretin expression inversely correlated with the expected level of analgesia (group 1<2<3). Moreover, in group 1, CSF noradrenaline decreased long term, cows were hypersensitive to mechanical stimulation, and they demonstrated signs of discomfort with higher motor activity and "agitation while lying" recorded from video analysis. Decreased "feeding behavior," observer-reported pain scales, electrodermal activity, and plasma cortisol concentration were inconsistent to differentiate pain intensity between groups. In summary, changes in CSF biomarkers and mechanical sensitization reflected modulation of central

  8. No Effect of a Single Session of Transcranial Direct Current Stimulation on Experimentally Induced Pain in Patients with Chronic Low Back Pain – An Exploratory Study

    PubMed Central

    Luedtke, Kerstin; May, Arne; Jürgens, Tim P.

    2012-01-01

    Transcranial direct current stimulation (tDCS) has been shown to modulate cortical excitability. A small number of studies suggested that tDCS modulates the response to experimental pain paradigms. No trials have been conducted to evaluate the response of patients already suffering from pain, to an additional experimental pain before and after tDCS. The present study investigated the effect of a single session of anodal, cathodal and sham stimulation (15 mins/1 mA) over the primary motor cortex on the perceived intensity of repeated noxious thermal and electrical stimuli and on elements of quantitative sensory testing (thermal pain and perception thresholds) applied to the right hand in 15 patients with chronic low back pain. The study was conducted in a double-blind sham-controlled and cross-over design. No significant alterations of pain ratings were found. Modalities of quantitative sensory testing remained equally unchanged. It is therefore hypothesized that a single 15 mins session of tDCS at 1 mA may not be sufficient to alter the perception of experimental pain and in patients with chronic pain. Further studies applying repetitive tDCS to patients with chronic pain are required to fully answer the question whether experimental pain perception may be influenced by tDCS over the motor cortex. PMID:23189136

  9. No effect of a single session of transcranial direct current stimulation on experimentally induced pain in patients with chronic low back pain--an exploratory study.

    PubMed

    Luedtke, Kerstin; May, Arne; Jürgens, Tim P

    2012-01-01

    Transcranial direct current stimulation (tDCS) has been shown to modulate cortical excitability. A small number of studies suggested that tDCS modulates the response to experimental pain paradigms. No trials have been conducted to evaluate the response of patients already suffering from pain, to an additional experimental pain before and after tDCS. The present study investigated the effect of a single session of anodal, cathodal and sham stimulation (15 mins/1 mA) over the primary motor cortex on the perceived intensity of repeated noxious thermal and electrical stimuli and on elements of quantitative sensory testing (thermal pain and perception thresholds) applied to the right hand in 15 patients with chronic low back pain. The study was conducted in a double-blind sham-controlled and cross-over design. No significant alterations of pain ratings were found. Modalities of quantitative sensory testing remained equally unchanged. It is therefore hypothesized that a single 15 mins session of tDCS at 1 mA may not be sufficient to alter the perception of experimental pain and in patients with chronic pain. Further studies applying repetitive tDCS to patients with chronic pain are required to fully answer the question whether experimental pain perception may be influenced by tDCS over the motor cortex. PMID:23189136

  10. Experimental tooth clenching. A model for studying mechanisms of muscle pain.

    PubMed

    Dawson, Andreas

    2013-01-01

    The overall goal of this thesis was to broaden knowledge of pain mechanisms in myofascial temporomandibular disorders (M-TMD). The specific aims were to: Develop a quality assessment tool for experimental bruxism studies (study I). Investigate proprioceptive allodynia after experimental tooth clenching exercises (study II). Evaluate the release of serotonin (5-HT), glutamate, pyruvate, and lactate in healthy subjects (study III) and in patients with M-TMD (study IV), after experimental tooth clenching exercises. In (I), tool development comprised 5 steps: (i) preliminary decisions, (ii) item generation, (iii) face-validity assessment, (iv) reliability and discriminative validity testing, and (v) instrument refinement. After preliminary decisions and a literature review, a list of 52 items to be considered for inclusion in the tool was generated. Eleven experts were invited to participate on the Delphi panel, of which 10 agreed. After four Delphi rounds, 8 items remained and were included in the Quality Assessment Tool for Experimental Bruxism Studies (Qu-ATEBS). Inter-observer reliability was acceptable (k = 0.77), and discriminative validity high (phi coefficient 0.79; P < 0.01). During refinement, 1 item was removed; the final tool comprised 7 items. In (II), 16 healthy females participated in three 60-min sessions, each with 24- and 48-h follow-ups. Participants were randomly assigned to a repetitive experimental tooth clenching task with a clenching level of 10%, 20%, or 40% of maximal voluntary clenching force (MVCF). Pain intensity, fatigue, perceived intensity of vibration (PIV), perceived discomfort (PD), and pressure pain threshold (PPT) were measured throughout. A significant increase in pain intensity and fatigue but not in PD was observed over time. A significant increase in PIV was only observed at 40 min, and PPT decreased significantly over time at 50 and 60 min compared to baseline. In (III), 30 healthy subjects (16 females, and 14 males

  11. Experimental tooth clenching. A model for studying mechanisms of muscle pain.

    PubMed

    Dawson, Andreas

    2013-01-01

    The overall goal of this thesis was to broaden knowledge of pain mechanisms in myofascial temporomandibular disorders (M-TMD). The specific aims were to: Develop a quality assessment tool for experimental bruxism studies (study I). Investigate proprioceptive allodynia after experimental tooth clenching exercises (study II). Evaluate the release of serotonin (5-HT), glutamate, pyruvate, and lactate in healthy subjects (study III) and in patients with M-TMD (study IV), after experimental tooth clenching exercises. In (I), tool development comprised 5 steps: (i) preliminary decisions, (ii) item generation, (iii) face-validity assessment, (iv) reliability and discriminative validity testing, and (v) instrument refinement. After preliminary decisions and a literature review, a list of 52 items to be considered for inclusion in the tool was generated. Eleven experts were invited to participate on the Delphi panel, of which 10 agreed. After four Delphi rounds, 8 items remained and were included in the Quality Assessment Tool for Experimental Bruxism Studies (Qu-ATEBS). Inter-observer reliability was acceptable (k = 0.77), and discriminative validity high (phi coefficient 0.79; P < 0.01). During refinement, 1 item was removed; the final tool comprised 7 items. In (II), 16 healthy females participated in three 60-min sessions, each with 24- and 48-h follow-ups. Participants were randomly assigned to a repetitive experimental tooth clenching task with a clenching level of 10%, 20%, or 40% of maximal voluntary clenching force (MVCF). Pain intensity, fatigue, perceived intensity of vibration (PIV), perceived discomfort (PD), and pressure pain threshold (PPT) were measured throughout. A significant increase in pain intensity and fatigue but not in PD was observed over time. A significant increase in PIV was only observed at 40 min, and PPT decreased significantly over time at 50 and 60 min compared to baseline. In (III), 30 healthy subjects (16 females, and 14 males

  12. Pain in experimental autoimmune encephalitis: a comparative study between different mouse models

    PubMed Central

    2012-01-01

    Background Pain can be one of the most severe symptoms associated with multiple sclerosis (MS) and develops with varying levels and time courses. MS-related pain is difficult to treat, since very little is known about the mechanisms underlying its development. Animal models of experimental autoimmune encephalomyelitis (EAE) mimic many aspects of MS and are well-suited to study underlying pathophysiological mechanisms. Yet, to date very little is known about the sensory abnormalities in different EAE models. We therefore aimed to thoroughly characterize pain behavior of the hindpaw in SJL and C57BL/6 mice immunized with PLP139-151 peptide or MOG35-55 peptide respectively. Moreover, we studied the activity of pain-related molecules and plasticity-related genes in the spinal cord and investigated functional changes in the peripheral nerves using electrophysiology. Methods We analyzed thermal and mechanical sensitivity of the hindpaw in both EAE models during the whole disease course. Qualitative and quantitative immunohistochemical analysis of pain-related molecules and plasticity-related genes was performed on spinal cord sections at different timepoints during the disease course. Moreover, we investigated functional changes in the peripheral nerves using electrophysiology. Results Mice in both EAE models developed thermal hyperalgesia during the chronic phase of the disease. However, whereas SJL mice developed marked mechanical allodynia over the chronic phase of the disease, C57BL/6 mice developed only minor mechanical allodynia over the onset and peak phase of the disease. Interestingly, the magnitude of glial changes in the spinal cord was stronger in SJL mice than in C57BL/6 mice and their time course matched the temporal profile of mechanical hypersensitivity. Conclusions Diverse EAE models bearing genetic, clinical and histopathological heterogeneity, show different profiles of sensory and pathological changes and thereby enable studying the mechanistic basis

  13. Pain hypervigilance is associated with greater clinical pain severity and enhanced experimental pain sensitivity among adults with symptomatic knee osteoarthritis

    PubMed Central

    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

  14. Indirect Acquisition of Pain-Related Fear: An Experimental Study of Observational Learning Using Coloured Cold Metal Bars

    PubMed Central

    Helsen, Kim; Vlaeyen, Johan W. S.; Goubert, Liesbet

    2015-01-01

    Background Previous research has demonstrated that pain-related fear can be acquired through observation of another’s pain behaviour during an encounter with a painful stimulus. The results of two experimental studies were presented, each with a different pain stimulus, of which the aim was to investigate the effect of observational learning on pain expectancies, avoidance behaviour, and physiological responding. Additionally, the study investigated whether certain individuals are at heightened risk to develop pain-related fear through observation. Finally, changes in pain-related fear and pain intensity after exposure to the feared stimulus were examined. Methods During observational acquisition, healthy female participants watched a video showing coloured cold metal bars being placed against the neck of several models. In a differential fear conditioning paradigm, one colour was paired with painful facial expressions, and another colour was paired with neutral facial expressions of the video models. During exposure, both metal bars with equal temperatures (-25° or +8° Celsius) were placed repeatedly against participants’ own neck. Results Results showed that pain-related beliefs can be acquired by observing pain in others, but do not necessarily cause behavioural changes. Additionally, dispositional empathy might play a role in the acquisition of these beliefs. Furthermore, skin conductance responses were higher when exposed to the pain-associated bar, but only in one of two experiments. Differential pain-related beliefs rapidly disappeared after first-hand exposure to the stimuli. Conclusions This study enhances our understanding of pain-related fear acquisition and subsequent exposure to the feared stimulus, providing leads for pain prevention and management strategies. PMID:25806969

  15. Vicarious pain while observing another in pain: an experimental approach

    PubMed Central

    Vandenbroucke, S.; Crombez, G.; Van Ryckeghem, D. M. L.; Brass, M.; Van Damme, S.; Goubert, L.

    2013-01-01

    Objective: This study aimed at developing an experimental paradigm to assess vicarious pain experiences. We further explored the putative moderating role of observer's characteristics such as hypervigilance for pain and dispositional empathy. Methods: Two experiments are reported using a similar procedure. Undergraduate students were selected based upon whether they reported vicarious pain in daily life, and categorized into a pain responder group or a comparison group. Participants were presented a series of videos showing hands being pricked whilst receiving occasionally pricking (electrocutaneous) stimuli themselves. In congruent trials, pricking and visual stimuli were applied to the same spatial location. In incongruent trials, pricking and visual stimuli were in the opposite spatial location. Participants were required to report on which location they felt a pricking sensation. Of primary interest was the effect of viewing another in pain upon vicarious pain errors, i.e., the number of trials in which an illusionary sensation was reported. Furthermore, we explored the effect of individual differences in hypervigilance to pain, dispositional empathy and the rubber hand illusion (RHI) upon vicarious pain errors. Results: Results of both experiments indicated that the number of vicarious pain errors was overall low. In line with expectations, the number of vicarious pain errors was higher in the pain responder group than in the comparison group. Self-reported hypervigilance for pain lowered the probability of reporting vicarious pain errors in the pain responder group, but dispositional empathy and the RHI did not. Conclusion: Our paradigm allows measuring vicarious pain experiences in students. However, the prevalence of vicarious experiences of pain is low, and only a small percentage of participants display the phenomenon. It remains however unknown which variables affect its occurrence. PMID:23781187

  16. Can personality traits and gender predict the response to morphine? An experimental cold pain study.

    PubMed

    Pud, Dorit; Yarnitsky, David; Sprecher, Elliot; Rogowski, Zeev; Adler, Rivka; Eisenberg, Elon

    2006-02-01

    The aim of the present study was to examine the possible role of personality traits, in accordance with Cloninger's theory, and gender, in the variability of responsiveness to opioids. Specifically, it was intended to test whether or not the three personality dimensions - harm avoidance (HA), reward dependence (RD) and novelty seeking (NS) - as suggested by Cloninger, can predict inter-personal differences in responsiveness to morphine after exposure to experimental cold pain. Thirty-four healthy volunteers (15 females, 19 males) were given the cold pressor test (CPT). Pain threshold, tolerance, and magnitude (VAS) were measured before and after (six measures, 30 min apart) the administration of either 0.5 mg/kg oral morphine sulphate (n=21) or 0.33 mg/kg oral active placebo (diphenhydramine) (n=13) in a randomized, double blind design. Assessment of the three personality traits, according to Cloninger's Tridimensional Personality Questionnaire, was performed before the CPT. A high HA score (but not RD, NS, or baseline values of the three pain parameters) predicted a significantly larger pain relief following the administration of morphine sulphate (but not of the placebo). Women exhibited a larger response in response to both treatments, as indicated by a significantly increased threshold and tolerance following morphine sulphate as well as significantly increased tolerance and decreased magnitude following placebo administration. The present study confirms the existence of individual differences in response to analgesic treatment. It suggests that high HA personality trait is associated with better responsiveness to morphine treatment, and that females respond better than men to both morphine and placebo.

  17. Isolated and combined effects of electroacupuncture and meditation in reducing experimentally induced ischemic pain: a pilot study.

    PubMed

    Choi, Kyung-Eun; Musial, Frauke; Amthor, Nadine; Rampp, Thomas; Saha, Felix J; Michalsen, Andreas; Dobos, Gustav J

    2011-01-01

    Acupuncture and meditation are promising treatment options for clinical pain. However, studies investigating the effects of these methods on experimental pain conditions are equivocal. Here, the effects of electroacupuncture (EA) and meditation on the submaximum effort tourniquet technique (SETT), a well-established, opiate-sensitive pain paradigm in experimental placebo research were studied. Ten experienced meditators (6 male subjects) and 13 nonmeditators (6 male subjects) were subjected to SETT (250 mmHG) on one baseline (SETT only) and two treatment days (additional EA contralaterally to the SETT, either at the leg on ST36 and LV3 or at the arm on LI4 and LI10 in randomized order). Numeric Rating Scale (NRS) ratings (scale 0-10) were recorded every 3 min. During baseline, meditation induced significantly greater pain tolerance in meditators when compared with the control group. Both the EA conditions significantly increased pain tolerance and reduced pain ratings in controls. Furthermore, EA diminished the group difference in pain sensitivity, indicating that meditators had no additional benefit from acupuncture. The data suggest that EA as a presumable bottom-up process may be as effective as meditation in controlling experimental SETT pain. However, no combined effect of both the techniques could be observed.

  18. Dysfunctional pain inhibition in patients with chronic whiplash-associated disorders: an experimental study.

    PubMed

    Daenen, Liesbeth; Nijs, Jo; Roussel, Nathalie; Wouters, Kristien; Van Loo, Michel; Cras, Patrick

    2013-01-01

    Inefficient endogenous pain inhibition, in particular impaired conditioned pain modulation (CPM), may disturb central pain processing in patients with chronic whiplash-associated disorders (WAD). Previous studies revealed that abnormal central pain processing is responsible for a wide range of symptoms in patients with chronic WAD. Hence, the present study aimed at examining the functioning of descending pain inhibitory pathways, and in particular CPM, in patients with chronic WAD. Thirty-five patients with chronic WAD and 31 healthy controls were subjected to an experiment evaluating CPM. CPM was induced by an inflated occlusion cuff and evaluated by comparing temporal summation (TS) of pressure pain prior to and during cuff inflation. Temporal summation was provoked by means of 10 consecutive pressure pulses at upper and lower limb location. Pain intensity of first, fifth, and 10th pressure pulse was rated. During heterotopic noxious conditioning stimulation, TS of pressure pain was significantly depleted among healthy controls. In contrast, TS was quite similar prior to and during cuff inflation in chronic WAD, providing evidence for dysfunctional CPM in patients with chronic WAD. The present study demonstrates a lack of endogenous pain inhibitory pathways, and in particularly CPM, in patients with chronic WAD, and hence provides additional evidence for the presence of central sensitization in chronic WAD.

  19. An experimental study of shared sensitivity to physical pain and social rejection.

    PubMed

    Eisenberger, Naomi I; Jarcho, Johanna M; Lieberman, Matthew D; Naliboff, Bruce D

    2006-12-15

    Recent evidence points to a possible overlap in the neural systems underlying the distressing experience that accompanies physical pain and social rejection (Eisenberger et al., 2003). The present study tested two hypotheses that stem from this suggested overlap, namely: (1) that baseline sensitivity to physical pain will predict sensitivity to social rejection and (2) that experiences that heighten social distress will heighten sensitivity to physical pain as well. In the current study, participants' baseline cutaneous heat pain unpleasantness thresholds were assessed prior to the completion of a task that manipulated feelings of social distress. During this task, participants played a virtual ball-tossing game, allegedly with two other individuals, in which they were either continuously included (social inclusion condition) or they were left out of the game by either never being included or by being overtly excluded (social rejection conditions). At the end of the game, three pain stimuli were delivered and participants rated the unpleasantness of each. Results indicated that greater baseline sensitivity to pain (lower pain unpleasantness thresholds) was associated with greater self-reported social distress in response to the social rejection conditions. Additionally, for those in the social rejection conditions, greater reports of social distress were associated with greater reports of pain unpleasantness to the thermal stimuli delivered at the end of the game. These results provide additional support for the hypothesis that pain distress and social distress share neurocognitive substrates. Implications for clinical populations are discussed. PMID:16890354

  20. Neuronal and immunological basis of action of antidepressants in chronic pain - clinical and experimental studies.

    PubMed

    Mika, Joanna; Zychowska, Magdalena; Makuch, Wioletta; Rojewska, Ewelina; Przewlocka, Barbara

    2013-01-01

    The current knowledge of the pharmacological actions of the tricyclic antidepressants (TCAs) has slowly evolved through their over 40-year history. Chronic pain represents one of the most important public health problems, and antidepressants are an essential part of the therapeutic strategy in addition to classical analgesics. This article reviews the available evidence on the efficacy and safety of antidepressants in chronic pain conditions; namely, headaches, low back pain, fibromyalgia, cancer pain and especially neuropathic pain. TCAs are traditionally the main type of depression medication used to treat chronic pain. Recently, new antidepressants were introduced into clinical use, with a significant reduction in side effects and equivalent efficacy on mood disorders. These new drugs that are effective for chronic pain belong to the tetracyclic antidepressants (TeCAs) group (amoxapine, maprotiline), the serotonin and noradrenaline reuptake inhibitors (SNRIs) group (duloxetine, venlafaxine, milnacipran) and the atypical antidepressants group (bupropion, trazodone, mirtazapine, nefazodone). In this review, we present the available publications on TCAs (amitriptyline, doxepin, imipramine, desipramine, nortriptyline), TeCAs (amoxapine, maprotiline), selective serotonin reuptake inhibitors (SSRIs) (citalopram, fluoxetine, paroxetine), SNRIs (duloxetine, venlafaxine, milnacipran) and atypical antidepressants (bupropion) for the treatment of neuropathic pain. We also review analgesics acting as both opioid receptor agonists and also acting as aminergic reuptake inhibitors. Existing data are insufficient to conclude which of these new classes of antidepressants has the best clinical profile and will be the most effective in the treatment of neuropathic pain; in addition, a lower incidence of side effects should be considered. Increased experimental and translational research is a key for further improvement of the treatment of chronic pain with antidepressants. However

  1. [Treatment of chronic back pain with antidepressant cymbalta: an experimental study].

    PubMed

    Voznesenskaia, T G; Leonova, A R; Kaverina, I V

    2007-01-01

    Thirty-two patients at the acute stage of chronic back pain have been studied. Cymbalta was used as a monotherapy in dosage 60 mg daily during 6 weeks simultaneously with traditional non-pharmacological therapy. Treatment efficacy was assessed using self-rating methods and quantitative scales measuring pain intensity as well as Spilberger trait/state anxiety inventory, Beck depression scale, Plutchik scale measuring psychological defense mechanisms, quality of sleep, quality of life and evaluation of autonomic dysfunction. The treatment with cymbalta resulted in significant reduction of pain in 90% patients, with full stopping of the syndrome in 10% and marked reduction in 55%. The stopping of pain syndrome was correlated with significant improvement of emotional status and quality of life and sleep normalization of the patients. PMID:18379477

  2. Reduced habituation to experimental pain in migraine patients: a CO(2) laser evoked potential study.

    PubMed

    Valeriani, M; de Tommaso, M; Restuccia, D; Le Pera, D; Guido, M; Iannetti, G D; Libro, G; Truini, A; Di Trapani, G; Puca, F; Tonali, P; Cruccu, G

    2003-09-01

    The habituation to sensory stimuli of different modalities is reduced in migraine patients. However, the habituation to pain has never been evaluated. Our aim was to assess the nociceptive pathway function and the habituation to experimental pain in patients with migraine. Scalp potentials were evoked by CO(2) laser stimulation (laser evoked potentials, LEPs) of the hand and facial skin in 24 patients with migraine without aura (MO), 19 patients with chronic tension-type headache (CTTH), and 28 control subjects (CS). The habituation was studied by measuring the changes of LEP amplitudes across three consecutive repetitions of 30 trials each (the repetitions lasted 5 min and were separated by 5-min intervals). The slope of the regression line between LEP amplitude and number of repetitions was taken as an index of habituation. The LEPs consisted of middle-latency, low-amplitude responses (N1, contralateral temporal region, and P1, frontal region) followed by a late, high-amplitude, negative-positive complex (N2/P2, vertex). The latency and amplitude of these responses were similar in both patients and controls. While CS and CTTH patients showed a significant habituation of the N2/P2 response, in MO patients this LEP component did not develop any habituation at all after face stimulation and showed a significantly lower habituation than in CS after hand stimulation. The habituation index of the vertex N2/P2 complex exceeded the normal limits in 13 out of the 24 MO patients and in none of the 19 CTTH patients (P<0.0001; Fisher's exact test). Moreover, while the N1-P1 amplitude showed a significant habituation in CS after hand stimulation, it did not change across repetitions in MO patients. In conclusion, no functional impairment of the nociceptive pathways, including the trigeminal pathways, was found in either MO or CTTH patients. But patients with migraine had a reduced habituation, which probably reflects an abnormal excitability of the cortical areas involved in

  3. Reduced habituation to experimental pain in migraine patients: a CO(2) laser evoked potential study.

    PubMed

    Valeriani, M; de Tommaso, M; Restuccia, D; Le Pera, D; Guido, M; Iannetti, G D; Libro, G; Truini, A; Di Trapani, G; Puca, F; Tonali, P; Cruccu, G

    2003-09-01

    The habituation to sensory stimuli of different modalities is reduced in migraine patients. However, the habituation to pain has never been evaluated. Our aim was to assess the nociceptive pathway function and the habituation to experimental pain in patients with migraine. Scalp potentials were evoked by CO(2) laser stimulation (laser evoked potentials, LEPs) of the hand and facial skin in 24 patients with migraine without aura (MO), 19 patients with chronic tension-type headache (CTTH), and 28 control subjects (CS). The habituation was studied by measuring the changes of LEP amplitudes across three consecutive repetitions of 30 trials each (the repetitions lasted 5 min and were separated by 5-min intervals). The slope of the regression line between LEP amplitude and number of repetitions was taken as an index of habituation. The LEPs consisted of middle-latency, low-amplitude responses (N1, contralateral temporal region, and P1, frontal region) followed by a late, high-amplitude, negative-positive complex (N2/P2, vertex). The latency and amplitude of these responses were similar in both patients and controls. While CS and CTTH patients showed a significant habituation of the N2/P2 response, in MO patients this LEP component did not develop any habituation at all after face stimulation and showed a significantly lower habituation than in CS after hand stimulation. The habituation index of the vertex N2/P2 complex exceeded the normal limits in 13 out of the 24 MO patients and in none of the 19 CTTH patients (P<0.0001; Fisher's exact test). Moreover, while the N1-P1 amplitude showed a significant habituation in CS after hand stimulation, it did not change across repetitions in MO patients. In conclusion, no functional impairment of the nociceptive pathways, including the trigeminal pathways, was found in either MO or CTTH patients. But patients with migraine had a reduced habituation, which probably reflects an abnormal excitability of the cortical areas involved in

  4. Effects of a Hypnotic Induction and an Unpleasantness-Focused Analgesia Suggestion on Pain Catastrophizing to an Experimental Heat Stimulus: A Preliminary Study.

    PubMed

    Adachi, Tomonori; Nakae, Aya; Sasaki, Jun

    2016-01-01

    Pain catastrophizing is associated with greater levels of pain. While many studies support the efficacy of hypnosis for pain, the effect on pain catastrophizing remains unclear. The present study evaluated the effect of hypnosis on pain catastrophizing using experimental heat stimulation. Twenty-two pain patients engaged in 3 conditions: baseline (no suggestion), hypnotic induction, and hypnotic induction plus analgesia suggestion. Participants with higher baseline pain showed a significant reduction in rumination following hypnotic induction plus analgesia suggestion and significant reductions in pain due to both the hypnotic induction alone and the hypnotic induction plus analgesia suggestion. The findings suggest that unpleasantness-focused hypnotic analgesia reduces pain via its effect on the rumination component of pain catastrophizing. PMID:27585727

  5. Brain Network Response to Acupuncture Stimuli in Experimental Acute Low Back Pain: An fMRI Study

    PubMed Central

    Shi, Yu; Liu, Ziping; Zhang, Shanshan; Li, Qiang; Guo, Shigui; Yang, Jiangming; Wu, Wen

    2015-01-01

    Most neuroimaging studies have demonstrated that acupuncture can significantly modulate brain activation patterns in healthy subjects, while only a few studies have examined clinical pain. In the current study, we combined an experimental acute low back pain (ALBP) model and functional magnetic resonance imaging (fMRI) to explore the neural mechanisms of acupuncture analgesia. All ALBP subjects first underwent two resting state fMRI scans at baseline and during a painful episode and then underwent two additional fMRI scans, once during acupuncture stimulation (ACUP) and once during tactile stimulation (SHAM) pseudorandomly, at the BL40 acupoint. Our results showed that, compared with the baseline, the pain state had higher regional homogeneity (ReHo) values in the pain matrix, limbic system, and default mode network (DMN) and lower ReHo values in frontal gyrus and temporal gyrus; compared with the OFF status, ACUP yielded broad deactivation in subjects, including nearly all of the limbic system, pain status, and DMN, and also evoked numerous activations in the attentional and somatosensory systems; compared with SHAM, we found that ACUP induced more deactivations and fewer activations in the subjects. Multiple brain networks play crucial roles in acupuncture analgesia, suggesting that ACUP exceeds a somatosensory-guided mind-body therapy for ALBP. PMID:26161117

  6. Brain Network Response to Acupuncture Stimuli in Experimental Acute Low Back Pain: An fMRI Study.

    PubMed

    Shi, Yu; Liu, Ziping; Zhang, Shanshan; Li, Qiang; Guo, Shigui; Yang, Jiangming; Wu, Wen

    2015-01-01

    Most neuroimaging studies have demonstrated that acupuncture can significantly modulate brain activation patterns in healthy subjects, while only a few studies have examined clinical pain. In the current study, we combined an experimental acute low back pain (ALBP) model and functional magnetic resonance imaging (fMRI) to explore the neural mechanisms of acupuncture analgesia. All ALBP subjects first underwent two resting state fMRI scans at baseline and during a painful episode and then underwent two additional fMRI scans, once during acupuncture stimulation (ACUP) and once during tactile stimulation (SHAM) pseudorandomly, at the BL40 acupoint. Our results showed that, compared with the baseline, the pain state had higher regional homogeneity (ReHo) values in the pain matrix, limbic system, and default mode network (DMN) and lower ReHo values in frontal gyrus and temporal gyrus; compared with the OFF status, ACUP yielded broad deactivation in subjects, including nearly all of the limbic system, pain status, and DMN, and also evoked numerous activations in the attentional and somatosensory systems; compared with SHAM, we found that ACUP induced more deactivations and fewer activations in the subjects. Multiple brain networks play crucial roles in acupuncture analgesia, suggesting that ACUP exceeds a somatosensory-guided mind-body therapy for ALBP. PMID:26161117

  7. The Effect of Oral Morphine on Pain-Related Brain Activation - An Experimental Functional Magnetic Resonance Imaging Study.

    PubMed

    Hansen, Tine Maria; Olesen, Anne Estrup; Graversen, Carina; Drewes, Asbjørn Mohr; Frøkjaer, Jens Brøndum

    2015-11-01

    Knowledge about cerebral mechanisms underlying pain perception and effect of analgesic drugs is important for developing methods for diagnosis and treatment of pain. The aim was to explore altered brain activation before and after morphine treatment using functional magnetic resonance imaging recorded during experimental painful heat stimulation. Functional magnetic resonance imaging data were recorded and analysed in 20 healthy volunteers (13 men and 7 women, 24.9 ± 2.6 years) in a randomized, double-blind, placebo-controlled, cross-over study. Painful stimulations were applied to the right forearm using a contact heat evoked potential stimulator (CHEPS) before and after treatment with 30 mg oral morphine and placebo. CHEPS stimulations before treatment induced activation in the anterior cingulate cortex, secondary somatosensory cortex/insula, thalamus and cerebellum (n = 16, p < 0.05). In response to morphine treatment, the spatial extent of these pain-specific areas decreased (n = 20). Reduced pain-induced activation was seen in the right insula, anterior cingulate cortex and inferior parietal cortex after morphine treatment compared to before treatment (n = 16, p < 0.05), and sensory ratings of pain perception were significantly reduced after morphine treatment (p = 0.02). No effect on pain-induced brain activation was seen after placebo treatment compared to before treatment (n = 12, p > 0.05). In conclusion, heat stimulation activated areas in the 'pain matrix' and a clinically relevant dose of orally administered morphine revealed significant changes in brain areas where opioidergic pathways are predominant. The method may be useful to investigate the mechanisms of analgesics.

  8. The effect of experimental low back pain on lumbar muscle activity in people with a history of clinical low back pain: a muscle functional MRI study.

    PubMed

    Danneels, Lieven; Cagnie, Barbara; D'hooge, Roseline; De Deene, Yves; Crombez, Geert; Vanderstraeten, Guy; Parlevliet, Thierry; Van Oosterwijck, Jessica

    2016-02-01

    In people with a history of low back pain (LBP), structural and functional alterations have been observed at several peripheral and central levels of the sensorimotor pathway. These existing alterations might interact with the way the sensorimotor system responds to pain. We examined this assumption by evaluating the lumbar motor responses to experimental nociceptive input of 15 participants during remission of unilateral recurrent LBP. Quantitative T2 images (muscle functional MRI) were taken bilaterally of multifidus, erector spinae, and psoas at several segmental levels (L3 upper and L4 upper and lower endplate) and during several conditions: 1) at rest, 2) upon trunk-extension exercise without pain, and 3) upon trunk-extension exercise with experimental induced pain at the clinical pain-side (1.5-ml intramuscular hypertonic saline injections in erector spinae). Following experimental pain induction, muscle activity levels similarly reduced for all three muscles, on both painful and nonpainful sides, and at multiple segmental levels (P = 0.038). Pain intensity and localization from experimental LBP were similar as during recalled clinical LBP episodes. In conclusion, unilateral and unisegmental experimental LBP exerts a generalized and widespread decrease in lumbar muscle activity during remission of recurrent LBP. This muscle response is consistent with previous observed patterns in healthy people subjected to the same experimental pain paradigm. It is striking that similar inhibitory patterns in response to pain could be observed, despite the presence of preexisting alterations in the lumbar musculature during remission of recurrent LBP. These results suggest that motor output can modify along the course of recurrent LBP.

  9. Spontaneous Chronic Pain After Experimental Thoracotomy Revealed by Conditioned Place Preference: Morphine Differentiates Tactile Evoked Pain From Spontaneous Pain.

    PubMed

    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

  10. Spontaneous Chronic Pain After Experimental Thoracotomy Revealed by Conditioned Place Preference: Morphine Differentiates Tactile Evoked Pain From Spontaneous Pain.

    PubMed

    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

  11. Experimental pain ratings and reactivity of cortisol and soluble tumor necrosis factor-α receptor II following a trial of hypnosis: Results of a randomized controlled pilot study

    PubMed Central

    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

  12. The influence of experimental pain intensity in the local and referred pain area on somatosensory perception in the area of referred pain.

    PubMed

    Kosek, Eva; Hansson, Per

    2002-01-01

    The aim of this study was to investigate the influence of experimental pain intensity in the local and referred pain area on somatosensory perception thresholds in the area of referred pain. Pain was induced by intramuscular electrical stimulation of the left infraspinatus muscle in 12 healthy individuals. The stimulation corresponded to the local pain threshold ("mild local pain"), the referred pain threshold ("mild referred pain"), and a pain intensity corresponding to 2 on a 10-point category scale in the referred pain area ("moderate referred pain"). Quantitative sensory testing was performed to assess perception thresholds in the referred pain area and the homologous contralateral area before and during stimulation. Perception thresholds to light touch (LTTs), pressure pain (PPTs), and to innocuous as well as noxious warmth and cold were assessed. During stimulation the LTTs increased in the referred pain area compared to baseline, uninfluenced by pain intensity. Perception thresholds to innocuous cold and warmth increased bilaterally during the stimulation, without relation to pain intensity. Heat pain thresholds were not affected. Compared to baseline, PPTs increased bilaterally during stimulation corresponding to "mild local pain" and "mild referred pain", respectively, and a further increase was seen during "moderate referred pain". The decreased sensitivity to innocuous cold, warmth, and pressure pain was bilateral, indicating activation of endogenous net inhibitory mechanisms interacting bilaterally. We found no influence of pain intensity on somatosensory thresholds restricted to the referred pain area and light touch was the only affected modality in the referred pain area only.

  13. Experimental Pain Responses Support Peripheral and Central Sensitization in Patients with Unilateral Shoulder Pain

    PubMed Central

    Coronado, Rogelio A.; Simon, Corey B.; Valencia, Carolina; George, Steven Z.

    2013-01-01

    Objective The aims of this study were to 1) examine the pattern of experimental pain responses in the affected and non-affected extremities in patients with shoulder pain and 2) explore the intra-individual association between sensitization states derived from experimental pain testing. Methods Experimental pain responses from 58 patients with shoulder pain (17 females, ages 18 to 52) were compared to those from 56 age- and sex-matched healthy volunteers (16 females, ages 21 to 58). Experimental pain responses included pressure pain threshold (PPT), thermal pain threshold and tolerance, and suprathreshold heat pain response (SHPR). Comparisons were made between the affected and non-affected extremity of clinical participants and the average response of extremities in healthy participants. Peripheral and central sensitization indexes were computed for clinical participants using standardized scores and percentile cut-offs based on the data from the healthy control sample. Experimental pain responses in clinical participants observed beyond the 25th and 75th percentile of healthy control sample responses were used for investigation of intra-individual association of sensitization states. Results PPT on the affected side acromion and masseter of clinical participants were diminished compared to their non-affected side (p < 0.015). Bilateral sensitivity in clinical participants was noted for PPT at the acromion and SHPR (p < 0.015). Peripheral and central sensitization indexes demonstrated that individuals with shoulder pain present with variable patterns of peripheral and central sensitization. Conclusions Collectively, experimental pain responses supported peripheral and central sensitization in response to pressure and thermal stimuli. No clear association was made between individuals exhibiting peripheral or central sensitization and suggests heterogeneity in pain processing in this clinical population. PMID:23619203

  14. The influence of experimentally induced pain on shoulder muscle activity.

    PubMed

    Diederichsen, Louise Pyndt; Winther, Annika; Dyhre-Poulsen, Poul; Krogsgaard, Michael R; Nørregaard, Jesper

    2009-04-01

    Muscle function is altered in painful shoulder conditions. However, the influence of shoulder pain on muscle coordination of the shoulder has not been fully clarified. The aim of the present study was to examine the effect of experimentally induced shoulder pain on shoulder muscle function. Eleven healthy men (range 22-27 years), with no history of shoulder or cervical problems, were included in the study. Pain was induced by 5% hypertonic saline injections into the supraspinatus muscle or subacromially. Seated in a shoulder machine, subjects performed standardized concentric abduction (0 degrees -105 degrees) at a speed of approximately 120 degrees/s, controlled by a metronome. During abduction, electromyographic (EMG) activity was recorded by intramuscular wire electrodes inserted in two deeply located shoulder muscles and by surface-electrodes over six superficially located shoulder muscles. EMG was recorded before pain, during pain and after pain had subsided and pain intensity was continuously scored on a visual analog scale (VAS). During abduction, experimentally induced pain in the supraspinatus muscle caused a significant decrease in activity of the anterior deltoid, upper trapezius and the infraspinatus and an increase in activity of lower trapezius and latissimus dorsi muscles. Following subacromial injection a significantly increased muscle activity was seen in the lower trapezius, the serratus anterior and the latissimus dorsi muscles. In conclusion, this study shows that acute pain both subacromially and in the supraspinatus muscle modulates coordination of the shoulder muscles during voluntary movements. During painful conditions, an increased activity was detected in the antagonist (latissimus), which support the idea that localized pain affects muscle activation in a way that protects the painful structure. Further, the changes in muscle activity following subacromial pain induction tend to expand the subacromial space and thereby decrease the load

  15. Pain referral and regional deep tissue hyperalgesia in experimental human hip pain models.

    PubMed

    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.

  16. Experimental pelvic pain facilitates pain provocation tests and causes regional hyperalgesia.

    PubMed

    Palsson, Thorvaldur Skuli; Graven-Nielsen, Thomas

    2012-11-01

    The extra-articular sacroiliac joint (SIJ) structure is a potential source for low back and pelvic pain. This study hypothesised that experimental pain induced in a superficial pelvic ligament causes (1) hyperalgesia to pressure, (2) distinct pain referral, and (3) an increased frequency of positive pain provocation tests of the SIJ complex. Thirty healthy subjects (15 females) participated in this study designed as a randomised crossover trial. Pain was induced in the long posterior sacroiliac ligament by injection of hypertonic saline, with the contralateral ligament injected with isotonic saline as control. Pain intensity was assessed on an electronic visual analogue scale (VAS). Pressure pain thresholds (PPTs) and pain provocation tests were assessed on 3 occasions: at baseline, after injection, and when pain had subsided. PPT sites were located bilaterally at the injection site, lateral to spinous processes of S2 and L5, and at the gluteus medius and gastrocnemius muscles. Hypertonic saline caused significantly higher VAS scores and more extended pain referral than isotonic saline (P<0.001). PPTs at the injection site and lateral to S2 were significantly reduced after hypertonic saline compared with baseline and isotonic saline (P<0.002). Significantly more subjects had positive pain provocation tests after hypertonic (67% of subjects) compared with isotonic saline (20%; P<0.001). These data demonstrate that the extra-articular SIJ structure accommodates nociceptors that are capable of inducing pain referral and regional hyperalgesia sensitive to manual pain provocation tests similar to what previously have been found in pelvic girdle pain patients.

  17. A human experimental model of episodic pain.

    PubMed

    Petrini, Laura; Hennings, Kristian; Li, Xi; Negro, Francesco; Arendt-Nielsen, Lars

    2014-12-01

    An experimental model of daily episodic pain was developed to investigate peripheral sensitization and cortical reorganization in healthy individuals. Two experiments (A and B) were conducted. Experiments A and B consisted of one and five consecutive days, respectively, in which the participants were subjected to 45 min of intense painful cutaneous electrical stimulation (episodic pain session), using a stimulus paradigm that in animals has been shown to induce long-term potentiation. These electrical stimulations produced a verbal pain rating of approximately 85 on a 0-100 verbal rating scale (VRS). Physiological (blood flow and axon flare reflex), psychophysical (perception threshold and verbal pain ratings) and electrophysiological (128 channels recorded somatosensory evoked potential (SEP)) measurements were recorded. The stimulation evoked a visible axon flare reflex and caused significantly increased cutaneous blood flow around the site of the stimulation. Axon flare reflex and blood flow reached a plateau on day one in all the subjects and no significant changes between the days were observed. The results showed that the effect of the electrical stimulations changed over the five days; pain potentiation was induced on the first day (significant increase in the verbal pain ratings during the 45 min stimulation) but not on any of the subsequent days. After five days of subsequent pain induction, the global field power showed a significant reduction in P2 amplitude in the late stage (200-370 ms, in the central-parietal area). In conclusion, the results suggest that in healthy individuals this model of episodic pain produces a rapid adaptation after day one and that generates significant SEP changes at day five.

  18. SPONTANEOUS CHRONIC PAIN AFTER EXPERIMENTAL THORACTOMY REVEALED BY CONDITIONED PLACE PREFERENCE: morphine differentiates tactile evoked pain from spontaneous pain

    PubMed Central

    Hung, Ching-Hsia; Wang, Jeffrey Chi-Fei; Strichartz, Gary

    2015-01-01

    Chronic pain following surgery limits social activity, interferes with work and causes emotional suffering. A major component of such pain is 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 (40mg/kg) gave equivalent 2-3h long relief of tactile hypersensitivity, when tested 12-14 days post-operative. 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 one conditioning sesssion with morphine or gabapentin, both vs saline. The gabapentin-conditioned, but not the morphine-conditioned rats showed a significant preference for the analgesia-paired chamber, despite the two agents’ equivalent effect 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 two aspects of long-term post-operative pain. PMID:26116369

  19. A Novel Magnetic Stimulator Increases Experimental Pain Tolerance in Healthy Volunteers - A Double-Blind Sham-Controlled Crossover Study

    PubMed Central

    Kortekaas, Rudie; Konopka, Karl-Heinz; Harbers, Marten; van der Hoeven, Johannes H.; van Wijhe, Marten; Aleman, André; Maurits, Natasha M.

    2013-01-01

    The ‘complex neural pulse’TM (CNP) is a neuromodulation protocol employing weak pulsed electromagnetic fields (PEMF). A pioneering paper reported an analgesic effect in healthy humans after 30 minutes of CNP-stimulation using three nested whole head coils. We aimed to devise and validate a stimulator with a novel design entailing a multitude of small coils at known anatomical positions on a head cap, to improve applicability. The main hypothesis was that CNP delivery with this novel device would also increase heat pain thresholds. Twenty healthy volunteers were enrolled in this double-blind, sham-controlled, crossover study. Thirty minutes of PEMF (CNP) or sham was applied to the head. After one week the other treatment was given. Before and after each treatment, primary and secondary outcomes were measured. Primary outcome was heat pain threshold (HPT) measured with thermal quantitative sensory testing. Other outcomes were warmth detection threshold, and aspects of cognition, emotion and motor performance. As hypothesized heat pain threshold was significantly increased after the PEMF stimulation. All other outcomes were unaltered by the PEMF but there was a trend level reduction of cognitive performance after PEMF stimulation as measured by the digit-symbol substitution task. Results from this pilot study suggest that our device is able to stimulate the brain and to modulate its function. This is in agreement with previous studies that used similar magnetic field strengths to stimulate the brain. Specifically, pain control may be achieved with PEMF and for this analgesic effect, coil design does not appear to play a dominant role. In addition, the flexible configuration with small coils on a head cap improves clinical applicability. Trial Registration Dutch Cochrane Centre NTR1093 PMID:23620795

  20. Postamputation pain: studies on mechanisms.

    PubMed

    Nikolajsen, Lone

    2012-10-01

    Amputation is followed by both painful and non-painful phantom phenomena in a large number of amputees. Non-painful phantom sensations rarely pose any clinical problem, but 60-80% of all amputees also experience painful sensations (i.e. phantom pain) located to the missing limb. The severity of phantom pain usually decreases with time, but severe pain persists in 5-10% of patients. Pain in the residual limb (i.e. stump pain) is another consequence of amputation. Both stump and phantom pain can be very difficult to treat. Treatment guidelines used for other neuropathic pain conditions are probably the best approximation, especially for the treatment of stump pain. The aim of the present doctoral thesis was to explore some of the mechanisms underlying pain after amputation. Ten studies were carried out (I-X). My PhD thesis from 1998 dealt with pain before the amputation and showed that preamputation pain increases the risk of phantom pain after amputation (I). A perioperative epidural blockade, however, did not reduce the incidence of pain or abnormal sensory phenomena after amputation (II, III). The importance of sensitization before amputation for the subsequent development of pain is supported by study IV, in which pressure pain thresholds obtained at the limb before amputation were inversely related to stump and phantom pain after 1 week. Afferent input from the periphery is likely to contribute to postamputation pain as sodium channels were upregulated in human neuromas (VI), although neuroma removal did not always alleviate phantom pain (V). Sensitization of neurons in the spinal cord also seems to be involved in pain after amputation as phantom pain was reduced by ketamine, an NMDA-receptor antagonist. Another NMDA-receptor antagonist, memantine, and gabapentin, a drug working by binding to the δ2α-subunit of voltage-gated calcium channels, had no effect on phantom pain (VII-IX). Supraspinal factors are also important for pain after amputation as

  1. Ultrasound guided, painful electrical stimulation of lumbar facet joint structures: an experimental model of acute low back pain.

    PubMed

    O'Neill, Søren; Graven-Nielsen, Thomas; Manniche, Claus; Arendt-Nielsen, Lars

    2009-07-01

    Quantitative sensory testing has indicated generalized muscle hyperalgesia in patients with chronic low back pain. The temporal development of such hyperalgesia is not well understood. The aim of the present study was to demonstrate whether generalized muscle hyperalgesia can develop within minutes of acute low back pain using a new experimental model of lumbar facet joint pain. Thirteen healthy volunteers were included and baseline pressure pain thresholds were assessed at eight separate sites, outside the area of evoked low back and referred pain. Using ultrasonography, two electrode needles were placed either side of a lumbar facet joint (right L3-4) and used to induce experimental low back pain for 10 min with continuous stimulation. Thresholds, stimulus-response relationships, distribution and quality of the electrically induced pain were recorded. Electrical facet joint stimulation induced low back pain and pain referral into the anterior leg, ipsilaterally, proximal to the knee, similar to what is observed clinically. Pressure pain thresholds did not change significantly before, during and after facet joint stimulation. In conclusion, we describe a novel model of acute experimental low back pain and demonstrate that generalized hyperalgesia did not develop within minutes of acute low back pain. PMID:19376652

  2. Nonpainful wide-area compression inhibits experimental pain

    PubMed Central

    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

  3. Differences in pain-related fear acquisition and generalization: an experimental study comparing patients with fibromyalgia and healthy controls.

    PubMed

    Meulders, Ann; Jans, Anne; Vlaeyen, Johan W S

    2015-01-01

    Anomalies in fear learning, such as failure to inhibit fear to safe stimuli, lead to sustained anxiety, which in turn may augment pain. In the same vein, stimulus generalization is adaptive as it enables individuals to extrapolate the predictive value of 1 stimulus to similar stimuli. However, when fear spreads in an unbridled way to novel technically safe stimuli, stimulus generalization becomes maladaptive and may lead to dysfunctional avoidance behaviors and culminate in severe pain disability. In a voluntary movement conditioning paradigm, we compared the acquisition and generalization of pain-related fear in patients with fibromyalgia (FM) and healthy controls. During acquisition, participants received predictable pain in 1 context (ie, 1 movement predicts pain, whereas another does not), and unpredictable pain in another (ie, pain never contingent upon movement). Fear generalization to novel movements (resembling the original painful or nonpainful movement) was tested in both contexts. Results indicated that the FM group showed slower differential acquisition of pain-related fear in the predictable context, and more contextual pain-related fear in the unpredictable context. Fear of movement-related pain spreads selectively to novel movements similar to the original painful movement, and not to those resembling the nonpainful movement in the healthy controls, but nondifferential fear generalization was observed in FM. As expected, in the unpredictable context, we also observed nondifferential fear generalization; this effect was more pronounced in FM. Given the status of overgeneralization as a plausible transdiagnostic pathogenic marker, we believe that this research might increase our knowledge about pathogenesis of musculoskeletal widespread pain. PMID:25599307

  4. Differences in pain-related fear acquisition and generalization: an experimental study comparing patients with fibromyalgia and healthy controls.

    PubMed

    Meulders, Ann; Jans, Anne; Vlaeyen, Johan W S

    2015-01-01

    Anomalies in fear learning, such as failure to inhibit fear to safe stimuli, lead to sustained anxiety, which in turn may augment pain. In the same vein, stimulus generalization is adaptive as it enables individuals to extrapolate the predictive value of 1 stimulus to similar stimuli. However, when fear spreads in an unbridled way to novel technically safe stimuli, stimulus generalization becomes maladaptive and may lead to dysfunctional avoidance behaviors and culminate in severe pain disability. In a voluntary movement conditioning paradigm, we compared the acquisition and generalization of pain-related fear in patients with fibromyalgia (FM) and healthy controls. During acquisition, participants received predictable pain in 1 context (ie, 1 movement predicts pain, whereas another does not), and unpredictable pain in another (ie, pain never contingent upon movement). Fear generalization to novel movements (resembling the original painful or nonpainful movement) was tested in both contexts. Results indicated that the FM group showed slower differential acquisition of pain-related fear in the predictable context, and more contextual pain-related fear in the unpredictable context. Fear of movement-related pain spreads selectively to novel movements similar to the original painful movement, and not to those resembling the nonpainful movement in the healthy controls, but nondifferential fear generalization was observed in FM. As expected, in the unpredictable context, we also observed nondifferential fear generalization; this effect was more pronounced in FM. Given the status of overgeneralization as a plausible transdiagnostic pathogenic marker, we believe that this research might increase our knowledge about pathogenesis of musculoskeletal widespread pain.

  5. Hypnosis and Local Anesthesia for Dental Pain Relief-Alternative or Adjunct Therapy?-A Randomized, Clinical-Experimental Crossover Study.

    PubMed

    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.

  6. Hypnosis and Local Anesthesia for Dental Pain Relief-Alternative or Adjunct Therapy?-A Randomized, Clinical-Experimental Crossover Study.

    PubMed

    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. PMID:27585724

  7. Pain perception in people with Down syndrome: a synthesis of clinical and experimental research

    PubMed Central

    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

  8. Postural Responses to a Suddenly Released Pulling Force in Older Adults with Chronic Low Back Pain: An Experimental Study

    PubMed Central

    Lee, Pei-Yun; Lin, Sang-I; Liao, Yu-Ting; Lin, Ruey-Mo; Hsu, Che-Chia; Huang, Kuo-Yuan; Chen, Yi-Ting

    2016-01-01

    Chronic low back pain (CLBP), one of the most common musculoskeletal conditions in older adults, might affect balance and functional independence. The purpose of this study was to investigate the postural responses to a suddenly released pulling force in older adults with and without CLBP. Thirty community-dwelling older adults with CLBP and 26 voluntary controls without CLBP were enrolled. Participants were required to stand on a force platform while, with one hand, they pulled a string that was fastened at the other end to a 2-kg or to a 4-kg force in the opposite direction at a random order. The number of times the participants lost their balance and motions of center of pressure (COP) when the string was suddenly released were recorded. The results demonstrated that although the loss of balance rates for each pulling force condition did not differ between groups, older adults with CLBP had poorer postural responses: delayed reaction, larger displacement, higher velocity, longer path length, and greater COP sway area compared to the older controls. Furthermore, both groups showed larger postural responses in the 4-kg pulling force condition. Although aging is generally believed to be associated with declining balance and postural control, these findings highlight the effect of CLBP on reactive balance when responding to an externally generated force in an older population. This study also suggests that, for older adults with CLBP, in addition to treating them for pain and disability, reactive balance evaluation and training, such as reaction and movement strategy training should be included in their interventions. Clinicians and older patients with CLBP need to be made aware of the significance of impaired reactive balance and the increased risk of falls when encountering unexpected perturbations. PMID:27622646

  9. Postural Responses to a Suddenly Released Pulling Force in Older Adults with Chronic Low Back Pain: An Experimental Study.

    PubMed

    Lee, Pei-Yun; Lin, Sang-I; Liao, Yu-Ting; Lin, Ruey-Mo; Hsu, Che-Chia; Huang, Kuo-Yuan; Chen, Yi-Ting; Tsai, Yi-Ju

    2016-01-01

    Chronic low back pain (CLBP), one of the most common musculoskeletal conditions in older adults, might affect balance and functional independence. The purpose of this study was to investigate the postural responses to a suddenly released pulling force in older adults with and without CLBP. Thirty community-dwelling older adults with CLBP and 26 voluntary controls without CLBP were enrolled. Participants were required to stand on a force platform while, with one hand, they pulled a string that was fastened at the other end to a 2-kg or to a 4-kg force in the opposite direction at a random order. The number of times the participants lost their balance and motions of center of pressure (COP) when the string was suddenly released were recorded. The results demonstrated that although the loss of balance rates for each pulling force condition did not differ between groups, older adults with CLBP had poorer postural responses: delayed reaction, larger displacement, higher velocity, longer path length, and greater COP sway area compared to the older controls. Furthermore, both groups showed larger postural responses in the 4-kg pulling force condition. Although aging is generally believed to be associated with declining balance and postural control, these findings highlight the effect of CLBP on reactive balance when responding to an externally generated force in an older population. This study also suggests that, for older adults with CLBP, in addition to treating them for pain and disability, reactive balance evaluation and training, such as reaction and movement strategy training should be included in their interventions. Clinicians and older patients with CLBP need to be made aware of the significance of impaired reactive balance and the increased risk of falls when encountering unexpected perturbations. PMID:27622646

  10. Sex differences in experimental pain among healthy children: a systematic review and meta-analysis.

    PubMed

    Boerner, Katelynn E; Birnie, Kathryn A; Caes, Line; Schinkel, Meghan; Chambers, Christine T

    2014-05-01

    Sex differences in response to experimental pain are commonly reported in systematic reviews in the adult literature. The objective of the present research was to conduct a systematic review and meta-analysis of sex differences in healthy children's responses to experimental pain (e.g., cold pressor, heat pain, pressure pain) and, where possible, to conduct analyses separately for children and adolescents. A search was conducted of electronic databases for published papers in English of empirical research using experimental pain tasks to examine pain-related outcomes in healthy boys and girls between 0 and 18 years of age. Eighty articles were eligible for inclusion and were coded to extract information relevant to sex differences. The systematic review indicated that, across different experimental pain tasks, the majority of studies reported no significant differences between boys and girls on pain-related outcomes. However, the meta-analysis of available combined data found that girls reported significantly higher cold pressor pain intensity compared to boys in studies where the mean age of participants was greater than 12 years. Additionally, a meta-analysis of heat pain found that boys had significantly higher tolerance than girls overall, and boys had significantly higher heat pain threshold than girls in studies where the mean age of participants was 12 years or younger. These findings suggest that developmental stage may be relevant for understanding sex differences in pain.

  11. Experimental reduction of pain catastrophizing modulates pain report but not spinal nociception as verified by mediation analyses.

    PubMed

    Terry, Ellen L; Thompson, Kathryn A; Rhudy, Jamie L

    2015-08-01

    Pain catastrophizing is associated with enhanced pain; however, the mechanisms by which it modulates pain are poorly understood. Evidence suggests that catastrophizing modulates supraspinal processing of pain but does not modulate spinal nociception (as assessed by nociceptive flexion reflex [NFR]). Unfortunately, most NFR studies have been correlational. To address this, this study experimentally reduced catastrophizing to determine whether it modulates spinal nociception (NFR). Healthy pain-free participants (N = 113) were randomly assigned to a brief 30-minute catastrophizing reduction manipulation or a control group that received pain education. Before and after manipulations, 2 types of painful stimuli were delivered to elicit (1) NFR (single trains of stimuli) and (2) temporal summation of NFR (3 stimulations at 2 Hz). After each set of stimuli, participants were asked to report their pain intensity and unpleasantness, as well as their situation-specific catastrophizing. Manipulation checks verified that catastrophizing was effectively reduced. Furthermore, pain intensity and unpleasantness to both stimulation types were reduced by the catastrophizing manipulation, effects that were mediated by catastrophizing. Although NFRs were not affected by the catastrophizing manipulation, temporal summation of NFR was reduced. However, this effect was not mediated by catastrophizing. These results indicate that reductions in catastrophizing lead to reductions in pain perception but do not modulate spinal nociception and provides further evidence that catastrophizing modulates pain at the supraspinal, not the spinal, level.

  12. Human experimental pain models: A review of standardized methods in drug development

    PubMed Central

    Reddy, K. Sunil kumar; Naidu, M. U. R.; Rani, P. Usha; Rao, T. Ramesh Kumar

    2012-01-01

    Human experimental pain models are essential in understanding the pain mechanisms and appear to be ideally suited to test analgesic compounds. The challenge that confronts both the clinician and the scientist is to match specific treatments to different pain-generating mechanisms and hence reach a pain treatment tailored to each individual patient. Experimental pain models offer the possibility to explore the pain system under controlled settings. Standardized stimuli of different modalities (i.e., mechanical, thermal, electrical, or chemical) can be applied to the skin, muscles, and viscera for a differentiated and comprehensive assessment of various pain pathways and mechanisms. Using a multimodel-multistructure testing, the nociception arising from different body structures can be explored and modulation of specific biomarkers by new and existing analgesic drugs can be profiled. The value of human experimental pain models is to link animal and clinical pain studies, providing new possibilities for designing successful clinical trials. Spontaneous pain, the main compliant of the neuropathic patients, but currently there is no human model available that would mimic chronic pain. Therefore, current human pain models cannot replace patient studies for studying efficacy of analgesic compounds, although being helpful for proof-of-concept studies and dose finding. PMID:23626642

  13. The role of experimentally-induced subacromial pain on shoulder strength and throwing accuracy.

    PubMed

    Wassinger, Craig A; Sole, Gisela; Osborne, Hamish

    2012-10-01

    Shoulder injuries often comprise two separate yet related components, structural tissue damage and pain. The role of each of these components on shoulder function is difficult to ascertain. Experimental pain models allow the assessment of consequences of localized pain when applied to healthy individuals. By understanding the role of pain on shoulder function, clinicians will be able to more efficiently assess and treat shoulder injuries. The objective of the study was to evaluate the role of experimentally-induced sub-acromial pain on shoulder isokinetic rotational strength and throwing accuracy. This was a block counterbalanced, crossover, repeated measures study design utilizing 20 individuals without self-reported shoulder or cervical pathology. Shoulder function was measured with and without experimental pain injection (2 mL of 5% hypertonic saline) in the sub-acromial space. Functional tasks consisted of shoulder rotational strength utilizing isokinetic testing and throwing accuracy via the functional throwing performance index. The hypertonic saline induced moderate pain levels in all participants (4.3-5.1/10). Normalized shoulder internal (t = 3.76, p = 0.001) and external (t = 3.12, p = 0.006) rotation strength were both diminished in the painful condition compared to the pain free condition. Throwing accuracy was also reduced while the participants experienced pain (t = 3.99, p = 0.001). Moderate levels of experimental shoulder pain were sufficient to negatively influence shoulder strength and throwing accuracy in participants without shoulder pathology.

  14. Electromyographic response of shoulder muscles to acute experimental subacromial pain.

    PubMed

    Sole, Gisela; Osborne, Hamish; Wassinger, Craig

    2014-08-01

    This study investigated effects of experimentally-induced subacromial pain, induced via hypertonic saline injection, on shoulder muscles activity. Electromyographic activity of 20 healthy participants was assessed for humeral elevation and descent for the control and experimental pain conditions, using fine wire electrodes for subscapularis and supraspinatus and surface electrodes for middle deltoid, upper trapezius, lower trapezius, infraspinatus, and serratus anterior. Normalized mean amplitudes were analyzed for each muscle for four phases for elevation and descent, respectively. Repeated measures analysis of variances (ANOVAs) were used to determine differences between muscle activity in the control and experimental condition for the four phases of elevation and descent. Differences for mean normalized amplitudes were not significant during humeral elevation. Increased activity was found for the pain condition for serratus anterior and middle deltoid during the first (120-90°) and third (60-30°) parts and decreased activity for infraspinatus in the second half of descent (60-0°). No significant differences were found during descent for upper and lower trapezius, subscapularis and supraspinatus. While increased serratus anterior activity during 60-30° of descent may be protective, increased middle deltoid and decreased infraspinatus activity during the same range may threaten subacromial tissues in that range. Overall the changes in muscle activation were individual specific, particularly during the concentric elevation phase. PMID:24685367

  15. Between-muscle differences in the adaptation to experimental pain.

    PubMed

    Hug, François; Hodges, Paul W; van den Hoorn, Wolbert; Tucker, Kylie

    2014-11-15

    This study aimed to determine whether muscle stress (force per unit area) can be redistributed between individual heads of the quadriceps muscle when pain is induced into one of these heads. Elastography was used to measure muscle shear elastic modulus (an index of muscle stress). Electromyography (EMG) was recorded from vastus lateralis (VL), vastus medialis (VM), and rectus femoris (RF). In experiment I (n = 20), participants matched a knee extension force, and thus any reduction of stress within the painful muscle would require compensation by other muscles. In experiment II (n = 13), participants matched VL EMG amplitude and were free to vary external force such that intermuscle compensation would be unnecessary to maintain the experimental task. In experiments I and II, pain was induced by injection of hypertonic saline into VM or RF. Experiment III aimed to establish whether voluntary drive to the individual muscles could be controlled independently. Participants (n = 13) were asked to voluntarily reduce activation of VM or RF while maintaining knee extension force. During VM pain, there was no change in shear elastic modulus (experiments I and II) or EMG amplitude of VM (experiment II). In contrast, RF pain was associated with a reduction in RF elastic modulus (experiments I and II: -8 to -17%) and EMG amplitude (experiment II). Participants could voluntarily reduce EMG amplitude of RF (-26%; P = 0.003) but not VM (experiment III). These results highlight between-muscle differences in adaptation to pain that might be explained by their function (monoarticular vs. biarticular) and/or the neurophysiological constraints associated to their activation.

  16. Long-Term Effects of Interprofessional Biopsychosocial Rehabilitation for Adults with Chronic Non-Specific Low Back Pain: A Multicentre, Quasi-Experimental Study

    PubMed Central

    Semrau, Jana; Hentschke, Christian; Buchmann, Jana; Meng, Karin; Vogel, Heiner; Faller, Hermann; Bork, Hartmut; Pfeifer, Klaus

    2015-01-01

    Background 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. Methods 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). Results 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. Conclusion The interprofessional and interdisciplinary, biopsychosocial rehabilita-tion program PASTOR shows some improvements of the long-term effectiveness of inpatient

  17. Sex, Gender, and Pain: A Review of Recent Clinical and Experimental Findings

    PubMed Central

    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

  18. Effect of experimental muscle pain on maximal voluntary activation of human biceps brachii muscle.

    PubMed

    Khan, Serajul I; McNeil, Chris J; Gandevia, Simon C; Taylor, Janet L

    2011-09-01

    Muscle pain has widespread effects on motor performance, but the effect of pain on voluntary activation, which is the level of neural drive to contracting muscle, is not known. To determine whether induced muscle pain reduces voluntary activation during maximal voluntary contractions, voluntary activation of elbow flexors was assessed with both motor-point stimulation and transcranial magnetic stimulation over the motor cortex. In addition, we performed a psychophysical experiment to investigate the effect of induced muscle pain across a wide range of submaximal efforts (5-75% maximum). In all studies, elbow flexion torque was recorded before, during, and after experimental muscle pain by injection of 1 ml of 5% hypertonic saline into biceps. Injection of hypertonic saline evoked deep pain in the muscle (pain rating ∼5 on a scale from 0 to 10). Experimental muscle pain caused a small (∼5%) but significant reduction of maximal voluntary torque in the motor-point and motor cortical studies (P < 0.001 and P = 0.045, respectively; n = 7). By contrast, experimental muscle pain had no significant effect on voluntary activation when assessed with motor-point and motor cortical stimulation although voluntary activation tested with motor-point stimulation was reduced by ∼2% in contractions after pain had resolved (P = 0.003). Furthermore, induced muscle pain had no significant effect on torque output during submaximal efforts (P > 0.05; n = 6), which suggests that muscle pain did not alter the relationship between the sense of effort and production of voluntary torque. Hence, the present study suggests that transient experimental muscle pain in biceps brachii has a limited effect on central motor pathways. PMID:21737829

  19. Adult attachment and reports of pain in experimentally-induced pain.

    PubMed

    Andrews, Nicole Emma; Meredith, Pamela Joy; Strong, Jenny

    2011-05-01

    Attachment theory has been proposed as a framework for understanding the development of chronic pain, with evidence supporting the overrepresentation of insecure attachment styles in chronic pain populations and links between insecure attachment and factors known to impact one's ability to cope with pain. The present study sought to extend two earlier studies exploring the relationships between adult attachment and communication of an acute pain experience, in anticipation of providing insight into individual differences in vulnerability in development of chronic pain. It was hypothesised that: (a) fearful attachment would be associated with perceptions of the pain as less intense, and (b) anxious attachment would be associated with lower pain thresholds. A convenience sample of 82 healthy adults completed self-report measures of attachment, neuroticism, and negative affect prior to taking part in a coldpressor pain inducement task. Results demonstrated that fearful attachment was associated with lower levels of pain intensity throughout the coldpressor task. In addition, dismissing attachment was also associated with less intense pain, as well as increased coldpressor endurance (tolerance) in the presence of a known assessor. These associations were retained after controlling for measures of neuroticism, negative affect, age, and social desirability. The results of this study are consistent with the proposition that fearful and dismissing individuals tend to mask their underlying distress caused by the pain experience, potentially leading to difficulties coping with pain over time.

  20. Experimental human pain models in gastro-esophageal reflux disease and unexplained chest pain

    PubMed Central

    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

  1. Central Pain Processing in Early-Stage Parkinson's Disease: A Laser Pain fMRI Study

    PubMed Central

    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

  2. Isometric force production parameters during normal and experimental low back pain conditions

    PubMed Central

    Descarreaux, Martin; Blouin, Jean-Sébastien; Teasdale, Normand

    2005-01-01

    Background The control of force and its between-trial variability are often taken as critical determinants of motor performance. Subjects performed isometric trunk flexion and extension forces without and with experiment pain to examine if pain yields changes in the control of trunk forces. The objective of this study is to determine if experimental low back pain modifies trunk isometric force production. Methods Ten control subjects participated in this study. They were required to exert 50 and 75% of their isometric maximal trunk flexion and extension torque. In a learning phase preceding the non painful and painful trials, visual and verbal feedbacks were provided. Then, subjects were asked to perform 10 trials without any feedback. Time to peak torque, time to peak torque variability, peak torque variability as well as constant and absolute error in peak torque were calculated. Time to peak and peak dF/dt were computed to determine if the first peak of dF/dt could predict the peak torque achieved. Results Absolute and constant errors were higher in the presence of a painful electrical stimulation. Furthermore, peak torque variability for the higher level of force was increased with in the presence of experimental pain. The linear regressions between peak dF/dt, time to peak dF/dt and peak torque were similar for both conditions. Experimental low back pain yielded increased absolute and constant errors as well as a greater peak torque variability for the higher levels of force. The control strategy, however, remained the same between the non painful and painful condition. Cutaneous pain affects some isometric force production parameters but modifications of motor control strategies are not implemented spontaneously. Conclusions It is hypothesized that adaptation of motor strategies to low back pain is implemented gradually over time. This would enable LBP patients to perform their daily tasks with presumably less pain and more accuracy. PMID:15703067

  3. Vitamin D, Race, and Experimental Pain Sensitivity in Older Adults with Knee Osteoarthritis

    PubMed Central

    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

  4. Effects of coping statements on experimental pain in chronic pain patients

    PubMed Central

    Roditi, Daniela; Robinson, Michael E; Litwins, Nola

    2009-01-01

    The present study measured the effects of catastrophizing self-statements and positive coping self-statements on cold pressor-induced pain. Participants were 58 adult chronic pain patients with current facial pain. It was hypothesized that catastrophizing would lead to a decrease in pain endurance whereas positive coping would lead to an increase in pain endurance. It was also hypothesized that catastrophizing would lead to an increase in peak pain intensity whereas positive coping would lead to a decrease in peak pain intensity. At pretest, participants submerged their nondominant hand in the cold pressor. Pain sensitivity ranges (PSR) were subsequently determined by calculating the difference between tolerance and threshold times. Ratings of peak pain intensity were measured using a pressure sensitive bladder/transducer. Participants underwent random assignment to either a catastrophizing group or a positive coping self-statement group. ANCOVA results revealed that on average, participants employing catastrophizing statements as a coping strategy experienced significantly lower PSR (M = 35.53, SD = 39.71) compared to participants employing positive coping self-statements (M = 73.70, SD = 86.14) when controlling for pretest PSR. Group assignment had no significant influence on peak pain intensity ratings. Thus, our results reveal that manipulation of coping causes changes in pain endurance. PMID:21197299

  5. Mechanisms of acupuncture analgesia for clinical and experimental pain.

    PubMed

    Staud, Roland; Price, Donald D

    2006-05-01

    There is convincing evidence that acupuncture (AP) is effective for the treatment of postoperative and chemotherapy-induced nausea/vomiting, as well as postoperative dental pain. Less convincing data support AP's efficacy for chronic pain conditions, including headache, fibromyalgia and low back pain. There is no evidence that AP is effective in treating addiction, insomnia, obesity, asthma or stroke deficits. AP seems to be efficacious for alleviating experimental pain by increasing pain thresholds in human subjects and it appears to activate analgesic brain mechanisms through the release of neurohumoral factors, some of which can be inhibited by the opioid antagonist naloxone. In contrast to placebo analgesia, AP-related pain relief takes some time to develop and to resolve. Furthermore, repetitive use of AP analgesia can result in tolerance that demonstrates cross-tolerance with morphine. However, it appears that not all forms of AP are equally effective for providing analgesia. In particular, electro-AP seems to best deliver stimuli that activate powerful opioid and nonopioid analgesic mechanisms. Thus, future carefully controlled clinical trials using adequate electro-AP may be able to provide the necessary evidence for relevant analgesia in chronic pain conditions, such as headache, fibromyalgia, irritable bowel syndrome and low back pain. PMID:16734514

  6. Assessing efficacy of non-opioid analgesics in experimental pain models in healthy volunteers: an updated review

    PubMed Central

    Staahl, Camilla; Olesen, Anne Estrup; Andresen, Trine; Arendt-Nielsen, Lars; Drewes, Asbjørn Mohr

    2009-01-01

    AIM Experimental pain models may help to evaluate the mechanisms of analgesics and target the clinical indications for their use. This review, the second in a series of two, addresses how the efficacy of non-opioid analgesics have been assessed in human volunteers using experimental pain models. METHODS A literature search was completed for randomized controlled studies that included human experimental pain models, healthy volunteers and non-opioid analgesics. RESULTS Nonsteroidal anti-inflammatory drugs worked against various types of acute pain as well as in hyperalgesia. Analgesia from paracetamol was difficult to detect in experimental pain and the pain needed to be assessed with very sensitive methods like evoked brain potentials. The N-methyl-D-aspartate antagonists exemplified by ketamine generally needed strong, long-lasting or repeated pain in the skin for detectable analgesia, whereas pain in muscle and viscera generally was more easily attenuated. Gabapentin worked well in several models, particularly those inducing hyperalgesia, whereas lamotrigine was weak in modulation of experimental pain. Imipramine attenuated pain in most experimental models, whereas amitriptyline had weaker effects. Delta-9-tetrahydrocannabinol attenuated pain in only a few models. CONCLUSIONS Pain induction and assessment are very important for the sensitivity of the pain models. Generally, experimental pain models need to be designed with careful consideration of the pharmacological mechanisms and pharmacokinetics of analgesics. The drawback with the different study designs is also discussed. This knowledge can aid the decisions that need to be taken when designing experimental pain studies for compounds entering Phase I and II trials. PMID:19740390

  7. Naturally occurring muscle pain during exercise: assessment and experimental evidence.

    PubMed

    Cook, D B; O'Connor, P J; Eubanks, S A; Smith, J C; Lee, M

    1997-08-01

    The objectives were: (i) to present a method for assessing muscle pain during exercise, (ii) to provide reliability and validity data in support of the measurement tool, (iii) to test whether leg muscle pain threshold during exercise was related to a commonly used measure of pain threshold pain during test, (iv) to examine the relationship between pain and exertion ratings, (v) to test whether leg muscle pain is related to performance, and (vi) to test whether a large dose of aspirin would delay leg muscle pain threshold and/or reduce pain ratings during exercise. In study 1, seven females and seven males completed three 1-min cycling bouts at three different randomly ordered power outputs. Pain was assessed using a 10-point pain scale. High intraclass correlations (R from 0.88 to 0.98) indicated that pain intensity could be rated reliably using the scale. In study 2, 11 college-aged males (age 21.3 +/- 1.3 yr) performed a ramped (24 W.min-1) maximal cycle ergometry test. A button was depressed when leg muscle pain threshold was reached. Pain threshold occurred near 50% of maximal capacity: 50.3 (+/- 12.9% Wmax), 48.6 (+/- 14.8% VO2max), and 55.8 (+/- 12.9% RPEmax). Pain intensity ratings obtained following pain threshold were positively accelerating function of the relative exercise intensity. Volitional exhaustion was associated with pain ratings of 8.2 (+/- 2.5), a value most closely associated with the verbal anchor "very strong pain." In study 3, participants completed the same maximal exercise test as in study 2 as well as leg cycling at 60 rpm for 8 s at four randomly ordered power outputs (100, 150, 200, and 250 W) on a separate day. Pain and RPE ratings were significantly lower during the 8-s bouts compared to those obtained at the same power outputs during the maximal cycle test. The results suggest that noxious metabolites of muscle contraction play a role in leg muscle pain during exercise. In study 4, moderately active male subjects (N = 19) completed

  8. Gut pain reactions in man: an experimental investigation using short and long duration transmucosal electrical stimulation.

    PubMed

    Arendt-Nielsen, L; Drewes, A M; Hansen, J B; Tage-Jensen, U

    1997-02-01

    Visceral pain is a substantial, clinical problem but unfortunately few experimental models are available to study this phenomenon in man. In the present study we inserted a stimulation catheter 5-10 cm into the ileo-sigmoidostomy of nine patients. The catheter contained six small, flexible electrodes separated by 4 mm. The gut was stimulated by single burst, repeated burst (five stimuli delivered at 2 Hz), or continuous burst stimuli (4 Hz for 30, 60, 90, and 120 s). The sensation (ST), pain detection (PDT), and pain tolerance (PTT) thresholds to single/repeated burst stimuli were determined. The location/size/sensitivity of referred pain after repeated/continuous stimulation were characterized. The brain potentials to single burst stimuli and to increasing stimulus intensity were measured. ST to single burst stimuli was easy to determine (8 mA) and to reproduce. The patients found it difficult to determine the PDT and PTT to single burst stimuli, however both thresholds were easily determined for repeated burst stimuli. The pain thresholds to single burst stimuli were twice as high as the thresholds to repeated burst stimuli, indicating the importance of central temporal summation for visceral pain. Minor changes in the stimulus location resulted in changes of the referred pain projection site. The words most frequently selected (78%) from the McGill Pain Questionnaire to describe repeated burst stimulations were shooting, pricking, flashing, and boring. The amplitude of the brain potentials increased at increasing stimulus intensity. A stimulus intensity giving an initial pain rating of around 5 on a 0-10 visual analog scale (VAS) was used for continuous stimulation. A general increase of the pain intensity and the area of referred pain was found during this stimulation. It was concluded that electrical stimulation of the human gut provokes pain and especially long sequences of visceral stimuli are adequate to evoke referred pain mimicking pain profiles of

  9. Experimental tonic hand pain modulates the corticospinal plasticity induced by a subsequent hand deafferentation.

    PubMed

    Mavromatis, N; Gagné, M; Voisin, J I A V; Reilly, K T; Mercier, C

    2016-08-25

    Sensorimotor reorganization is believed to play an important role in the development and maintenance of phantom limb pain, but pain itself might modulate sensorimotor plasticity induced by deafferentation. Clinical and basic research support this idea, as pain prior to amputation increases the risk of developing post-amputation pain. The aim of this study was to examine the influence of experimental tonic cutaneous hand pain on the plasticity induced by temporary ischemic hand deafferentation. Sixteen healthy subjects participated in two experimental sessions (Pain, No Pain) in which transcranial magnetic stimulation was used to assess corticospinal excitability in two forearm muscles (flexor carpi radialis and flexor digitorum superficialis) before (T0, T10, T20, and T40) and after (T60 and T75) inflation of a cuff around the wrist. The cuff was inflated at T45 in both sessions and in the Pain session capsaicin cream was applied on the dorsum of the hand at T5. Corticospinal excitability was significantly greater during the Post-inflation phase (p=0.002) and increased similarly in both muscles (p=0.861). Importantly, the excitability increase in the Post-inflation phase was greater for the Pain than the No-Pain condition (p=0.006). Post-hoc analyses revealed a significant difference between the two conditions during the Post-inflation phase (p=0.030) but no difference during the Pre-inflation phase (p=0.601). In other words, the corticospinal facilitation was greater when pain was present prior to cuff inflation. These results indicate that pain can modulate the plasticity induced by another event, and could partially explain the sensorimotor reorganization often reported in chronic pain populations. PMID:27291642

  10. Analgesics as Reinforcers with Chronic Pain: Evidence from Operant Studies

    PubMed Central

    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

  11. The transcendental meditation technique and acute experimental pain.

    PubMed

    Mills, W W; Farrow, J T

    1981-04-01

    The Transcendental Meditation (TM) technique decreases the distress associated with the experience of acute experimental pain. Fifteen advanced mediators and 15 controls were administered the cold pressor test before and after a 20 minute period of meditation (TM group) or relaxation (control group). Verbal reports of the intensity of pain sensation and pain distress were obtained at intervals during the cold pressor trials. Skin resistance and heart rate were measured throughout. The mean distress level for the TM group was significantly lower than controls during both trials; the mean pain sensation level for the TM group did not differ significantly from controls during either trial. Heart rate and skin resistant changed for both groups in the expected manner, with no significant differences between groups. The validity, implications, and possible causes of these results are discussed.

  12. Experimenter Effects on Pain Reporting in Women Vary across the Menstrual Cycle

    PubMed Central

    Vigil, Jacob M.; DiDomenico, Jared; Strenth, Chance; Coulombe, Patrick; Kruger, Eric; Mueller, Andrea A.; Guevara Beltran, Diego; Adams, Ian

    2015-01-01

    Background. Separate lines of research have shown that menstrual cycling and contextual factors such as the gender of research personnel influence experimental pain reporting. Objectives. This study examines how brief, procedural interactions with female and male experimenters can affect experimentally reported pain (cold pressor task, CPT) across the menstrual cycle. Methods. Based on the menstrual calendars 94 naturally cycling women and 38 women using hormonal contraceptives (Mage = 19.83,  SD = 3.09) were assigned to low and high fertility groups. This assignment was based on estimates of their probability of conception given their current cycle day. Experimenters (12 males, 7 females) engaged in minimal procedural interactions with participants before the CPT was performed in solitude. Results. Naturally cycling women in the high fertility group showed significantly higher pain tolerance (81 sec, d = .79) following interactions with a male but not a female experimenter. Differences were not found for women in the low fertility or contraceptive groups. Discussion. The findings illustrate that menstrual functioning moderates the effect that experimenter gender has on pain reporting in women. Conclusion. These findings have implications for standardizing pain measurement protocols and understanding how basic biopsychosocial mechanisms (e.g., person-perception systems) can modulate pain experiences. PMID:25892990

  13. Clinical pharmacology of analgesics assessed with human experimental pain models: bridging basic and clinical research

    PubMed Central

    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

  14. Sex differences in how social networks and relationship quality influence experimental pain sensitivity.

    PubMed

    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

  15. A randomized, double-blind, positive-controlled, 3-way cross-over human experimental pain study of a TRPV1 antagonist (V116517) in healthy volunteers and comparison with preclinical profile.

    PubMed

    Arendt-Nielsen, Lars; Harris, Steve; Whiteside, Garth T; Hummel, Michele; Knappenberger, Terri; OʼKeefe, Sarah; Kapil, Ram; Kyle, Don

    2016-09-01

    This experimental, translational, experimental pain, single-center, randomized, double-blind, single-dose, 3-treatment, 3-period cross-over proof-of-concept volunteer trial studied the efficacy of a novel TRPV1 antagonist (V116517) on capsaicin- and UV-B-induced hyperalgesia. Heat and pressure pain thresholds, von Frey stimulus-response functions, and neurogenic inflammation were assessed together with safety. Each treatment period was 4 days. The 3 single oral treatments were 300 mg V116517, 400 mg celecoxib (a COX-2 inhibitor), and placebo. The heat pain detection and tolerance thresholds were increased significantly (P < 0.0001) by V116517. Heat pain detection and tolerance thresholds showed significantly less capsaicin hyperalgesia after V116517 (P = 0.004 and P < 0.0001, respectively). Celecoxib reduced UV-B-provoked pressure pain sensitization (P = 0.01). Laser Doppler flowmetry and erythema index after UV-B were significantly (P < 0.0001) reduced by celecoxib. Stimulus-response function in capsaicin-treated areas showed significant differences between both celecoxib and placebo and between V116517 and placebo. The body temperature showed no change, and no side effects were reported for any of the treatments. The TRPV1 antagonists and the COX-2 inhibitor showed different antihyperalgesic profiles indicating different clinical targets. In addition, the preclinical profile of V116517 in rat models of UV-B and capsaicin-induced hypersensitivity was compared with the human experimental data and overall demonstrated an alignment between 2 of the 3 end points tested. The TRPV1 antagonist showed a potent antihyperalgesic action without changing the body temperature but heat analgesia may be a potential safety issue. PMID:27168361

  16. 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.

  17. Adaptability to pain is associated with potency of local pain inhibition, but not conditioned pain modulation: a healthy human study.

    PubMed

    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.

  18. The effect of spinal manipulative therapy on experimentally induced pain: a systematic literature review

    PubMed Central

    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

  19. Inflammation-induced pain sensitization in men and women: does sex matter in experimental endotoxemia?

    PubMed Central

    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

  20. Inflammation-induced pain sensitization in men and women: does sex matter in experimental endotoxemia?

    PubMed

    Wegner, Alexander; Elsenbruch, Sigrid; Rebernik, Laura; Roderigo, Till; Engelbrecht, Elisa; Jäger, Marcus; Engler, Harald; Schedlowski, Manfred; Benson, Sven

    2015-10-01

    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.

  1. Inflammation-induced pain sensitization in men and women: does sex matter in experimental endotoxemia?

    PubMed

    Wegner, Alexander; Elsenbruch, Sigrid; Rebernik, Laura; Roderigo, Till; Engelbrecht, Elisa; Jäger, Marcus; Engler, Harald; Schedlowski, Manfred; Benson, Sven

    2015-10-01

    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

  2. Pain management in trauma: A review study

    PubMed Central

    Ahmadi, Alireza; Bazargan-Hejazi, Shahrzad; Heidari Zadie, Zahra; Euasobhon, Pramote; Ketumarn, Penkae; Karbasfrushan, Ali; Amini-Saman, Javad; Mohammadi, Reza

    2016-01-01

    Abstract: Background: Pain in trauma has a role similar to the double-edged sword. On the one hand, pain is a good indicator to determine the severity and type of injury. On the other hand, pain can induce sever complications and it may lead to further deterioration of the patient. Therefore, knowing how to manage pain in trauma patients is an important part of systemic approach in trauma. The aim of this manuscript is to provide information about pain management in trauma in the Emergency Room settings. Methods: In this review we searched among electronic and manual documents covering a 15-yr period between 2000 and 2016. Our electronic search included Pub Med, Google scholar, Web of Science, and Cochrane databases. We looked for articles in English and in peer-reviewed journals using the following keywords: acute pain management, trauma, emergency room and injury. Results: More than 3200 documents were identified. After screening based on the study inclusion criteria, 560 studies that had direct linkage to the study aim were considered for evaluation based World Health Organization (WHO) pain ladder chart. Conclusions: To provide adequate pain management in trauma patients require: adequate assessment of age-specific pharmacologic pain management; identification of adequate analgesic to relieve moderate to severe pain; cognizance of serious adverse effects of pain medications and weighting medications against their benefits, and regularly reassessing patients and reevaluating their pain management regimen. Patient-centered trauma care will also require having knowledge of barriers to pain management and discussing them with the patient and his/her family to identify solutions. PMID:27414816

  3. Complex regional pain syndrome (CRPS) or continuous unilateral distal experimental pain stimulation in healthy subjects does not bias visual attention towards one hemifield.

    PubMed

    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.

  4. Pain Behavior Changes Following Disc Puncture Relate to Nucleus Pulposus Rather than to the Disc Injury Per Se: An Experimental Study in Rats

    PubMed Central

    Nilsson, Elin; Nakamae, Toshio; Olmarker, Kjell

    2011-01-01

    It has previously been demonstrated that disc puncture in the rat induced changes in grooming and wet dog shakes, two behavioral changes that may be linked to discomfort and neuropathic pain. In this study the aim was to separate the effects of disc injury and the epidural presence of nucleus pulposus. Following anesthesia, the L4-5 disc was exposed using a dorsal approach. Ten rats received a superficial disc injury without nucleus pulposus leakage and ten rats received nucleus pulposus from a donor rat without disc injury. In ten animals the L4-5 disc was punctured using a ventral approach, with 10 corresponding controls. Spontaneous behavior was assessed after surgery. The data was matched to historical control of dorsal sham surgery and disc puncture. The study showed that the effects of nucleus pulposus were more pronounced than the effects induced by the disc injury. Ventral disc puncture did not induce any behavioral changes different from sham exposure. In conclusion, the data from the study indicate that behavioral changes induced by disc puncture are more likely to relate to the epidural presence of nucleus pulposus than the disc injury per se. PMID:21566734

  5. Antinociceptive Interaction of Tramadol with Gabapentin in Experimental Mononeuropathic Pain.

    PubMed

    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.

  6. The effect of cognitive bias modification for interpretation on avoidance of pain during an acute experimental pain task.

    PubMed

    Jones, Emma Blaisdale; Sharpe, Louise

    2014-08-01

    Research confirms that patients with chronic pain show a tendency to interpret ambiguous stimuli as pain related. However, whether modifying these interpretive pain biases impacts pain outcomes is unknown. This study aimed to demonstrate that interpretation biases towards pain can be modified, and that changing these biases influences pain outcomes in the cold pressor task. One hundred and six undergraduate students were randomly allocated to receive either threatening or reassuring information regarding the cold pressor. They also were randomly allocated to 1 of 2 conditions in the Ambiguous Scenarios Task, in which they were trained to have either a threatening interpretation of pain (pain bias condition) or a nonthreatening interpretation of pain (no pain bias condition). Therefore, the study had a 2 (threat/reassuring)×2 (pain bias/no pain bias) design. Analyses showed that a bias was induced contingent on condition, and that the threat manipulation was effective. Participants in the pain bias condition hesitated more before doing the cold pressor task than those in the no pain bias condition, as did those in the threat compared with the reassurance condition. The major finding was that interpretive bias mediated the relationship between bias condition and hesitance time, supporting the causal role of interpretive biases for avoidance behaviors in current chronic pain models. No differences were found on other pain outcomes regarding bias or threat, and the efficacy of the bias modification was not impacted by different levels of threat. These results suggest that cognitive bias modification should be further explored as a potential intervention in pain.

  7. Common trace elements alleviate pain in an experimental mouse model.

    PubMed

    Tamba, Bogdan I; Leon, Maria-Magdalena; Petreus, Tudor

    2013-04-01

    Trace elements represent a group of essential metals or metaloids necessary for life, present in minute amounts. Analgesic adjuvants can enhance the effect of other pain drugs or be used for pain control themselves. Previous studies on the effects of trace elements on nociception and their potential use as analgesic adjuvants have yielded conflicting results. In this study, we tested the hypothesis that three vital trace elements (Zn²⁺, Mg²⁺, Cu²⁺) have direct antinociceptive effects. Groups of eight Swiss mice were intraperitoneally (i.p) injected with incremental concentrations of Zn²⁺ sulfate (0.5, 2.0 mg/kg), Zn²⁺ citrate (0.125, 0.5 mg/kg), Mg²⁺ chloride (37.5, 75, 150 mg/kg), Cu²⁺ chloride (0.5, 1.0, 2.0 mg/kg), and Cu²⁺ sulfate (0.5, 1.0 mg/kg) or saline (control). Evaluations were made by hot plate (HP) and tail flick (TF) tests for central antinociceptive effect, writhing test (WT) for visceral antinociceptive effect, and activity cage (AC) test for spontaneous behavior. Zn²⁺ induced pain inhibition in HP/TF tests (up to 17%) and WT (up to 25%), with no significant differences among the salts used. Mg²⁺ salts induced pain inhibition for all performed tests (up to 85% in WT). Cu²⁺ salts showed antinociceptive effects for HP/TF (up to 28.6%) and WT (57.28%). Only Mg²⁺ and Cu²⁺ salts have displayed significant effects in AC (Mg²⁺ anxiolytic/depressant effect; Cu²⁺ anxiolytic effect). We interpret these data to mean that all tested trace elements induced antinociceptive effects in central and visceral pain tests. Our data indicate the potential use of these cheap adjuvants in pain therapy. PMID:23362003

  8. Endogenous Opioid Antagonism in Physiological Experimental Pain Models: A Systematic Review

    PubMed Central

    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

  9. Kinesthetic illusions attenuate experimental muscle pain, as do muscle and cutaneous stimulation.

    PubMed

    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. PMID:25935692

  10. Opioid pathways activation mediates the activity of nicorandil in experimental models of nociceptive and inflammatory pain.

    PubMed

    Dutra, Marcela M G B; Nascimento Júnior, Elias B; Godin, Adriana M; Brito, Ana Mercy S; Melo, Ivo S F; Augusto, Paulo S A; Rodrigues, Felipe F; Araújo, Débora P; de Fátima, Ângelo; Coelho, Márcio M; Machado, Renes R

    2015-12-01

    We have previously demonstrated that nicorandil inhibits the second phase of the nociceptive response induced by formaldehyde. In the present study, we evaluated the effects induced by nicorandil in other models of nociceptive and inflammatory pain in mice and also whether opioid pathways activation mediates its activity. As we have previously demonstrated, per os (p.o.) administration of nicorandil (50, 100 or 150mg/kg; -1h) inhibited the second phase of the nociceptive response induced by intraplantar (i.pl.) injection of formaldehyde. Nicorandil (50, 100 or 150mg/kg; p.o., -1h) also exhibited activity in models of inflammatory pain induced by i.pl. injection of carrageenan (300μg) and nociceptive pain induced by exposure to noxious heat (50°C). Intraperitoneal (i.p.) administration of the opioid antagonist naltrexone (1, 5 or 10mg/kg, -30min) attenuated or abolished the antinociceptive activity of nicorandil (100mg/kg, p.o.) in the three experimental pain models. In conclusion, we demonstrate that nicorandil exhibits activity in different models of nociceptive and inflammatory pain. The demonstration that the antinociceptive effect induced by nicorandil is markedly attenuated by an opioid antagonist provides solid information about an important mechanism mediating the activity of this antianginal drug. Altogether, our data suggest that the clinical pain relief induced by nicorandil in heart ischemic conditions may result from both vasodilation and intrinsic analgesic activity. PMID:26522924

  11. Stress and thermoregulation: different sympathetic responses and different effects on experimental pain.

    PubMed

    Fechir, M; Schlereth, T; Kritzmann, S; Balon, S; Pfeifer, N; Geber, C; Breimhorst, M; Eberle, T; Gamer, M; Birklein, F

    2009-10-01

    Stress and thermoregulation both activate the sympathetic nervous system (SNS) but might differently affect pain. Studies investigating possible interactions in patients are problematic because of the high prevalence of SNS disturbances in patients. We therefore analyzed the influence of these different sympathetic challenges on experimentally-induced pain in healthy subjects. SNS was activated in two different ways: by mental stress (Stroop task, mental arithmetic task), and by thermoregulatory stimulation using a water-perfused thermal suit (7 degrees C, 32 degrees C, or 50 degrees C). Attentional effects of the mental stress tasks were controlled by using easy control tasks. Both, stress and thermoregulatory stimuli, robustly activated SNS parameters. However, the patterns of activation were different. While stress co-activated heart rate, blood pressure, peripheral vasoconstriction and sweating, thermal stimulation either increased blood pressure (cold) or heart rate and sweating (warm). Only stress was able to induce a significant reduction of pain. The control tasks neither activated the SNS nor altered pain perception. Our results suggest that (1) different patterns of sympathetic activation can be recorded after stress and thermoregulatory challenges and (2) that only stress is able to interfere with sensation of experimental pain. Whether SNS activation is causally responsible for analgesia needs to be further investigated.

  12. Experimental muscle pain results in reorganization of coordination among trapezius muscle subdivisions during repetitive shoulder flexion.

    PubMed

    Falla, Deborah; Farina, Dario; Graven-Nielsen, Thomas

    2007-04-01

    The aim of the study was to examine the effect of experimental unilateral upper trapezius muscle pain on the relative activation of trapezius muscle subdivisions bilaterally during repetitive movement of the upper limb. Surface EMG signals were detected from nine healthy subjects from the upper, middle and lower divisions of trapezius during a repetitive bilateral shoulder flexion task. Measurements were performed before and after injection of 0.5 ml hypertonic (pain condition) and isotonic (control) saline into the upper division of the right trapezius muscle in two experimental sessions. On the painful side, upper trapezius showed decreased EMG amplitude (average rectified value, ARV) and lower trapezius increased ARV throughout the entire task following the injection of hypertonic saline (40.0 +/- 22.2 vs. 26.0 +/- 17.4 microV, and 12.5 +/- 7.6 vs. 25.6 +/- 14.8 microV, respectively, at the beginning of the contraction). On the side contralateral to pain, greater estimates of ARV were identified for the upper division of trapezius as the task progressed (37.4 +/- 20.2 vs. 52.7 +/- 28.4 microV, at the end of the contraction). Muscle fiber conduction velocity did not change with pain in all three divisions of the right trapezius muscle. The results suggest that local elicitation of nociceptive afferents in the upper division of the trapezius induces reorganization in the coordinated activity of the three subdivisions of the trapezius in repetitive dynamic tasks.

  13. Parenting in the context of chronic pain: A controlled study of parents with chronic pain

    PubMed Central

    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

  14. The genetic influences on oxycodone response characteristics in human experimental pain.

    PubMed

    Olesen, Anne E; Sato, Hiroe; Nielsen, Lecia M; Staahl, Camilla; Droney, Joanne; Gretton, Sophy; Branford, Ruth; Drewes, Asbjørn M; Arendt-Nielsen, Lars; Riley, Julia; Ross, Joy

    2015-08-01

    Human experimental pain studies are of value to study basic pain mechanisms under controlled conditions. The aim of this study was to investigate whether genetic variation across selected mu-, kappa- and delta-opioid receptor genes (OPRM1, OPRK1and OPRD1, respectively) influenced analgesic response to oxycodone in healthy volunteers. Experimental multimodal, multitissue pain data from previously published studies carried out in Caucasian volunteers were used. Data on thermal skin pain tolerance threshold (PTT) (n = 37), muscle pressure PTT (n = 31), mechanical visceral PTT (n = 43) and thermal visceral PTT (n = 41) were included. Genetic associations with pain outcomes were explored. Nineteen opioid receptor genetic polymorphisms were included in this study. Variability in oxycodone response to skin heat was associated with OPRM1 single-nucleotide polymorphisms (SNPs) rs589046 (P < 0.0001) and rs563649 (P < 0.0001). Variability in oxycodone response to visceral pressure was associated with four OPRM1 SNPs: rs589046 (P = 0.015), rs1799971 (P = 0.045), rs9479757 (P = 0.009) and rs533586 (P = 0.046). OPRM1 SNPs were not associated with oxycodone visceral heat threshold, however, one OPRD1 rs419335 reached significance (P = 0.015). Another OPRD1 SNP rs2234918 (P = 0.041) was associated with muscle pressure. There were no associations with OPRK1 SNPs and oxycodone response for any of the pain modalities. Associations were found between analgesic effects of oxycodone and OPRM1 and OPRD1 SNPs; therefore, variation in opioid receptor genes may partly explain responder characteristics to oxycodone.

  15. Chronic pain in Australia: a prevalence study.

    PubMed

    Blyth, F M; March, L M; Brnabic, A J; Jorm, L R; Williamson, M; Cousins, M J

    2001-01-01

    This study reports chronic pain prevalence in a randomly selected sample of the adult Australian population. Data were collected by Computer-Assisted Telephone Interview (CATI) using randomly generated telephone numbers and a two-stage stratified sample design. Chronic pain was defined as pain experienced every day for three months in the six months prior to interview. There were 17,543 completed interviews (response rate=70.8%). Chronic pain was reported by 17.1% of males and 20.0% of females. For males, prevalence peaked at 27.0% in the 65--69 year age group and for females, prevalence peaked at 31.0% in the oldest age group (80--84 years). Having chronic pain was significantly associated with older age, female gender, lower levels of completed education, and not having private health insurance; it was also strongly associated with receiving a disability benefit (adjusted OR=3.89, P<0.001) or unemployment benefit (adjusted OR=1.99, P<0.001); being unemployed for health reasons (adjusted OR=6.41, P<0.001); having poor self-rated health (adjusted OR=7.24, P<0.001); and high levels of psychological distress (adjusted OR=3.16, P<0.001). Eleven per cent of males and 13.5% of females in the survey reported some degree of interference with daily activities caused by their pain. Prevalence of interference was highest in the 55--59 year age group in both males (17.2%) and females (19.7%). Younger respondents with chronic pain were proportionately most likely to report interference due to pain, affecting 84.3% of females and 75.9% of males aged 20--24 years with chronic pain. Within the subgroup of respondents reporting chronic pain, the presence of interference with daily activities caused by pain was significantly associated with younger age; female gender; and not having private health insurance. There were strong associations between having interfering chronic pain and receiving disability benefits (adjusted OR=3.31, P<0.001) or being unemployed due to health reasons

  16. Evaluation of pain in rats through facial expression following experimental tooth movement.

    PubMed

    Liao, Lina; Long, Hu; Zhang, Li; Chen, Helin; Zhou, Yang; Ye, Niansong; Lai, Wenli

    2014-04-01

    This study was carried out to evaluate pain in rats by monitoring their facial expressions following experimental tooth movement. Male Sprague-Dawley rats were divided into the following five groups based on the magnitude of orthodontic force applied and administration of analgesics: control; 20 g; 40 g; 80 g; and morphine + 40 g. Closed-coil springs were used to mimic orthodontic forces. The facial expressions of each rat were videotaped, and the resulting rat grimace scale (RGS) coding was employed for pain quantification. The RGS score increased on day 1 but showed no significant change thereafter in the control and 20-g groups. In the 40- and 80-g groups, the RGS scores increased on day 1, peaked on day 3, and started to decrease on day 5. At 14 d, the RGS scores were similar in control and 20-, 40-, and 80-g groups and did not return to baseline. The RGS scores in the morphine + 40-g group were significantly lower than those in the control group. Our results reveal that coding of facial expression is a valid method for evaluation of pain in rats following experimental tooth movement. Inactivated springs (no force) still cause discomfort and result in an increase in the RGS. The threshold force magnitude required to evoke orthodontic pain in rats is between 20 and 40 g.

  17. Concept priming and pain: an experimental approach to understanding gender roles in sex-related pain differences.

    PubMed

    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.

  18. IL-17 is not essential for inflammation and chronic pelvic pain development in an experimental model of chronic prostatitis/chronic pelvic pain syndrome.

    PubMed

    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.

  19. Pharmacodynamic modelling of placebo and buprenorphine effects on event-related potentials in experimental pain.

    PubMed

    Juul, Rasmus V; Foster, David J R; Upton, Richard N; Andresen, Trine; Graversen, Carina; Drewes, Asbjørn M; Christrup, Lona L; Kreilgaard, Mads

    2014-10-01

    The purpose of the study was to investigate placebo and buprenorphine effects on event-related potentials (ERPs) in experimental pain and the potential benefit of population pharmacodynamic modelling in data analysis. Nineteen healthy volunteers received transdermal placebo and buprenorphine in a cross-over study. Drug plasma concentrations and ERPs after electrical stimulation at the median nerve with intensity adjusted to pain detection threshold were recorded until 144 hrs after administration. Placebo and concentration-effect models were fitted to data using non-linear mixed-effects modelling implemented in NONMEM (V7.2.0.). Pharmacodynamic models were developed to adequately describe both placebo and buprenorphine ERP data. Models predicted significant placebo effects, but did not predict significant effects related to buprenorphine concentration. Models revealed that ERPs varied both between subjects and between study occasions. ERPs were found to be reproducible within subjects and occasions as population variance was found to be eight times higher than the unexplained variances. Between-subject variance accounted for more than 75% of the population variance. In conclusion, pharmacodynamic modelling was successfully implemented to allow for placebo and variability correction in ERP of experimental pain. Improved outcome of ERP studies can be expected if variation between subjects and study occasions can be identified and described.

  20. Perception of experimental pain is reduced after provoked waking from rapid eye movement sleep.

    PubMed

    Daya, Vivek G; Bentley, Alison J

    2010-06-01

    Patients with chronic pain often complain of pain when they wake at night, but the accuracy of their perception of the pain after waking at night is unknown. While cognitive functions are reduced for a short time after waking from sleep, a situation known as sleep inertia, it is unclear how sleep inertia may affect the perception of pain. We investigated the effects of sleep inertia on the perception of experimentally induced pain. Fourteen male volunteers were exposed to a randomized thermal heat stimulus of 43.1 degrees C 'hot' and 46.5 degrees C 'hurting' during provoked waking from Stage 2 sleep, slow wave sleep and rapid eye movement (REM) sleep. Subjects rated their pain on awakening on a Visual Analogue Scale at 30 s after awakening and each minute thereafter for 5 min. We found no change in pain perception over the 5-min period irrespective of temperature used or sleep stage. However, perceived pain when awoken abruptly from REM sleep was significantly lower than the awake score for both the hot (P = 0.0069) and hurting (P = 0.0025) temperatures. Pain perception when woken from Stage 2 sleep or slow wave sleep was not significantly different from perception when awake. Our findings indicate that sleep inertia reduces pain perception when awoken abruptly from REM. This suggests that patients who wake up in pain either perceive accurately the pain they are experiencing, or at worst underestimate the level of pain if woken from REM sleep.

  1. Current studies on myofascial pain syndrome.

    PubMed

    Kuan, Ta-Shen

    2009-10-01

    Recent studies have clarified the nature of myofascial trigger points (MTrPs). In an MTrP region, multiple hyperirritable loci can be found. The sensory components of the MTrP locus are sensitized nociceptors that are responsible for pain, referred pain, and local twitch responses. The motor components are dysfunctional endplates that are responsible for taut band formation as a result of excessive acetylcholine (ACh) leakage. The concentrations of pain- and inflammation-related substances are increased in the MTrP region. It has been hypothesized that excessive ACh release, sarcomere shortening, and release of sensitizing substances are three essential features that relate to one another in a positive feedback cycle. This MTrP circuit is the connection among spinal sensory (dorsal horn) neurons responsible for the MTrP phenomena. Recent studies suggest that measurement of biochemicals associated with pain and inflammation in the MTrP region, the sonographic study of MTrPs, and the magnetic resonance elastography for taut band image are potential tools for the diagnosis of MTrPs. Many methods have been used to treat myofascial pain, including laser therapy, shockwave therapy, and botulinum toxin type A injection. PMID:19728962

  2. Current studies on myofascial pain syndrome.

    PubMed

    Kuan, Ta-Shen

    2009-10-01

    Recent studies have clarified the nature of myofascial trigger points (MTrPs). In an MTrP region, multiple hyperirritable loci can be found. The sensory components of the MTrP locus are sensitized nociceptors that are responsible for pain, referred pain, and local twitch responses. The motor components are dysfunctional endplates that are responsible for taut band formation as a result of excessive acetylcholine (ACh) leakage. The concentrations of pain- and inflammation-related substances are increased in the MTrP region. It has been hypothesized that excessive ACh release, sarcomere shortening, and release of sensitizing substances are three essential features that relate to one another in a positive feedback cycle. This MTrP circuit is the connection among spinal sensory (dorsal horn) neurons responsible for the MTrP phenomena. Recent studies suggest that measurement of biochemicals associated with pain and inflammation in the MTrP region, the sonographic study of MTrPs, and the magnetic resonance elastography for taut band image are potential tools for the diagnosis of MTrPs. Many methods have been used to treat myofascial pain, including laser therapy, shockwave therapy, and botulinum toxin type A injection.

  3. Comparison between the Analgesic Effect of two Techniques on the Level of Pain Perception During venipuncture in Children up to 7 Years of Age: A Quasi-Experimental Study

    PubMed Central

    Gupta, Vivek Vardhan; Kaur, Amanlo; Singla, Ruku; Chitkara, Neha; Bajaj, Krushnan V.; Rawat, H.C.L

    2014-01-01

    Background: Distraction techniques are often provided by nurses, parents or child life specialists and help in pain alleviation during procedures. The use of non pharmacological procedures to cope with pain behaviour is less costly and most of these procedures can be administered by a nurse. Hence, the aim of the present study was to assess and compare the analgesic effect of holding the child by a family member versus holding the child by a family member along with an animation distraction intervention on the level of pain perception during venipuncture in children up to seven years of age. Materials and Methods: Purposive sampling technique was used to select 70 children admitted in paediatric ward of Guru Gobind Singh Medical Hospital, Faridkot, 35 children in each group viz. Group 1(child held by family member during venipuncture) and Group 2 (child held by family member along with an animation distraction during venipuncture) and video clippings were made for each subject in both groups. Standardized FLACC pain scale was used to assess the level of pain during venipuncture by seeing the video clips of procedure in both groups. Results: Findings revealed that the mean pain score of Group 1 was 3.86 and that of Group 2 was 2.43. Findings revealed that in Group 1 majority 31(88.57%) got severe pain and none remained relaxed during venipuncture whereas in Group 2 majority 10(28.58%) got moderate pain, 09(25.71%) remained relaxed and only 07(20%) got severe pain. The comparison of mean pain score of both groups was checked statistically by computing independent t-test and the value of t comes out to be 7.199 with p-value 0.000*** which was found to be highly significant. Conclusion: The study concluded that when during painful procedures like venipuncture if children are given any non-pharmacological intervention like animated distraction along with their family member it helps in managing the pain. In other words, it distracts/diverts the child’s attention from

  4. Effect of experimentally induced low back pain on postural sway with breathing.

    PubMed

    Smith, Michelle; Coppieters, Michel W; Hodges, Paul W

    2005-09-01

    Although breathing perturbs balance, in healthy individuals little sway is detected in ground reaction forces because small movements of the spine and lower limbs compensate for the postural disturbance. When people have chronic low back pain (LBP), sway at the ground is increased, possibly as a result of reduced compensatory motion of the trunk. The aim of this study was to determine whether postural compensation for breathing is reduced during experimentally induced pain. Subjects stood on a force plate with eyes open, eyes closed, and while breathing with hypercapnoea before and after injection of hypertonic saline into the right lumbar longissimus muscle to induce LBP. Motion of the lumbar spine, pelvis, and lower limbs was measured with four inclinometers fixed over bony landmarks. During experimental pain, motion of the trunk in association with breathing was reduced. However, despite this reduction in motion, there was no increase in postural sway with breathing. These data suggest that increased body sway with breathing in people with chronic LBP is not simply because of reduced trunk movement, but instead, indicates changes in coordination by the central nervous system that are not replicated by experimental nociceptor stimulation.

  5. Effect of endocannabinoid degradation on pain: role of FAAH polymorphisms in experimental and postoperative pain in women treated for breast cancer.

    PubMed

    Cajanus, Kristiina; Holmström, Emil J; Wessman, Maija; Anttila, Verneri; Kaunisto, Mari A; Kalso, Eija

    2016-02-01

    Fatty acid amide hydrolase (FAAH) metabolizes the endocannabinoid anandamide, which has an important role in nociception. We investigated the role of common FAAH single-nucleotide polymorphisms (SNPs) in experimentally induced and postoperative pain. One thousand women undergoing surgery for breast cancer participated in the study. They were tested for cold (n = 900) and heat pain (n = 1000) sensitivity. After surgery, their pain intensities and analgesic consumption were carefully registered. FAAH genotyping was performed using MassARRAY platform and genome-wide chip (n = 926). Association between 8 FAAH SNPs and 9 pain phenotypes was analyzed using linear regression models. The results showed that carrying 2 copies of a missense variant converting proline at position 129 to threonine (rs324420) resulted in significantly lower cold pain sensitivity and less need for postoperative analgesia. More specifically, rs324420 and another highly correlated SNP, rs1571138, associated significantly with cold pain intensity (corrected P value, 0.0014; recessive model). Patients homozygous for the minor allele (AA genotype) were less sensitive to cold pain (β = -1.48; 95% CI, -2.14 to -0.8). Two other SNPs (rs3766246 and rs4660928) showed nominal association with cold pain, and SNPs rs4141964, rs3766246, rs324420, and rs1571138 nominal association with oxycodone consumption. In conclusion, FAAH gene variation was shown to associate with cold pain sensitivity with P129T/rs324420 being the most likely causal variant as it is known to reduce the FAAH enzyme activity. The same variant showed nominal association with postoperative oxycodone consumption. Our conclusions are, however, limited by the lack of replication and the results should be replicated in an independent cohort.

  6. Experimental pain processing in individuals with cognitive impairment: current state of the science.

    PubMed

    Defrin, Ruth; Amanzio, Martina; de Tommaso, Marina; Dimova, Violeta; Filipovic, Sasa; Finn, David P; Gimenez-Llort, Lydia; Invitto, Sara; Jensen-Dahm, Christina; Lautenbacher, Stefan; Oosterman, Joukje M; Petrini, Laura; Pick, Chaim G; Pickering, Gisele; Vase, Lene; Kunz, Miriam

    2015-08-01

    Cognitive impairment (CI) can develop during the course of ageing and is a feature of many neurological and neurodegenerative diseases. Many individuals with CI have substantial, sustained, and complex health care needs, which frequently include pain. However, individuals with CI can have difficulty communicating the features of their pain to others, which in turn presents a significant challenge for effective diagnosis and treatment of their pain. Herein, we review the literature on responsivity of individuals with CI to experimental pain stimuli. We discuss pain responding across a large number of neurological and neurodegenerative disorders in which CI is typically present. Overall, the existing data suggest that pain processing is altered in most individuals with CI compared with cognitively intact matched controls. The precise nature of these alterations varies with the type of CI (or associated clinical condition) and may also depend on the type of pain stimulation used and the type of pain responses assessed. Nevertheless, it is clear that regardless of the etiology of CI, patients do feel noxious stimuli, with more evidence for hypersensitivity than hyposensitivity to these stimuli compared with cognitively unimpaired individuals. Our current understanding of the neurobiological mechanisms underpinning these alterations is limited but may be enhanced through the use of animal models of CI, which also exhibit alterations in nociceptive responding. Further research using additional behavioural indices of pain is warranted. Increased understanding of altered experimental pain processing in CI will facilitate the development of improved diagnostic and therapeutic approaches for pain in individuals with CI.

  7. Experimental pain processing in individuals with cognitive impairment: current state of the science.

    PubMed

    Defrin, Ruth; Amanzio, Martina; de Tommaso, Marina; Dimova, Violeta; Filipovic, Sasa; Finn, David P; Gimenez-Llort, Lydia; Invitto, Sara; Jensen-Dahm, Christina; Lautenbacher, Stefan; Oosterman, Joukje M; Petrini, Laura; Pick, Chaim G; Pickering, Gisele; Vase, Lene; Kunz, Miriam

    2015-08-01

    Cognitive impairment (CI) can develop during the course of ageing and is a feature of many neurological and neurodegenerative diseases. Many individuals with CI have substantial, sustained, and complex health care needs, which frequently include pain. However, individuals with CI can have difficulty communicating the features of their pain to others, which in turn presents a significant challenge for effective diagnosis and treatment of their pain. Herein, we review the literature on responsivity of individuals with CI to experimental pain stimuli. We discuss pain responding across a large number of neurological and neurodegenerative disorders in which CI is typically present. Overall, the existing data suggest that pain processing is altered in most individuals with CI compared with cognitively intact matched controls. The precise nature of these alterations varies with the type of CI (or associated clinical condition) and may also depend on the type of pain stimulation used and the type of pain responses assessed. Nevertheless, it is clear that regardless of the etiology of CI, patients do feel noxious stimuli, with more evidence for hypersensitivity than hyposensitivity to these stimuli compared with cognitively unimpaired individuals. Our current understanding of the neurobiological mechanisms underpinning these alterations is limited but may be enhanced through the use of animal models of CI, which also exhibit alterations in nociceptive responding. Further research using additional behavioural indices of pain is warranted. Increased understanding of altered experimental pain processing in CI will facilitate the development of improved diagnostic and therapeutic approaches for pain in individuals with CI. PMID:26181216

  8. Antihyperalgesic effect of pentoxifylline on experimental inflammatory pain.

    PubMed

    Vale, Mariana L; Benevides, Verônica M; Sachs, Daniela; Brito, Gerly A C; da Rocha, Francisco A C; Poole, Stephen; Ferreira, Sérgio H; Cunha, Fernando Q; Ribeiro, Ronaldo A

    2004-12-01

    The antihyperalgesic effect of pentoxifylline was investigated in three experimental pain models. Pentoxifylline (0.5-1.6 mg kg(-1)) given 30 min before the stimulus significantly inhibited the writhing response induced by the intraperitoneal (i.p.) administration of either acetic acid (-90%) or zymosan (-83%), but not that of iloprost, in mice, as well as the zymosan-induced articular hyperalgesia in the zymosan arthritis in rats (-50%). Pentoxifylline also inhibited the mechanical hypernociception in rats induced by the intraplantar injection of either carrageenin (-81%), bradykinin (-56%) or tumor necrosis factor alpha (TNF-alpha; -46%), but not that induced by interleukin-1beta (IL-1beta) or prostaglandin E(2) (PGE(2)). Pentoxifylline did not inhibit the nociceptive response in the hot plate test in mice. Further, the antinociceptive effect of pentoxifylline in the writhing test in mice and the zymosan-induced articular hyperalgesia were not reversed by the coadministration of the opioid receptor antagonist naloxone. Thus, pentoxifylline antinociceptive effect is probably not mediated at a central level. Pentoxifylline significantly reduced TNF-alpha (-43%) and IL-1beta (-42%) concentrations in the joint exudates of rats stimulated by intra-articular injection of zymosan and the production of both cytokines (-66 and -86%, respectively) by mouse peritoneal macrophages stimulated in vivo with zymosan as well as the expression of TNF-alpha at the tissue level in carrageenin-injected rat paws. In conclusion, the antinociceptive activity of pentoxifylline is associated with the inhibition of the release of both TNF-alpha and IL-1beta.

  9. Is it better to have controlled and lost than never to have controlled at all? An experimental investigation of control over pain.

    PubMed

    Crombez, Geert; Eccleston, Christopher; De Vlieger, Petra; Van Damme, Stefaan; De Clercq, Armand

    2008-07-31

    Trying to control pain is a common human goal. But little is know about what happens when one loses control over pain. This paper reports an experiment with 74 healthy volunteers, half of whom were given control over a pain stimulus and subsequently lost control, and half of whom never had control over the pain. This study investigates whether having had control and lost it would result in a more unpleasant pain experience, more fear about impending pain, a heightened vigilance to pain, and greater interference on a secondary task. Participants in the experimental group first learned to avoid a painful stimulus by correctly responding to a card sorting task, but later on lost control over the painful stimulus. In the yoked comparison group, participants had no control over the painful stimulus from the beginning. Results indicated that losing control over pain and, relatedly, attempting to control uncontrollable pain have significant costs such as a higher fear of the impending pain stimulus and retarded performance on a secondary task. When attempts to avoid pain are blocked, individuals persist in their avoidance attempts, try harder, and narrow their focus of attention upon the problem to be solved. These findings are discussed within the context of a dual process model of coping with uncontrollable adverse events [Brandtstädter J, Renner G. Tenacious goal pursuit and flexible goal adjustment: explication and age-related analysis of assimilative and accommodative strategies of coping. Psychol Aging 1990;5:58-67] and possible mechanisms for perseverance with ineffective solutions.

  10. Center of Pressure Displacement of Standing Posture during Rapid Movements Is Reorganised Due to Experimental Lower Extremity Muscle Pain

    PubMed Central

    Shiozawa, Shinichiro; Hirata, Rogerio Pessoto; Graven-Nielsen, Thomas

    2015-01-01

    Background 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. Methods 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. Results 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). Conclusions 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. PMID:26680777

  11. Pain point system scale (PPSS): a method for postoperative pain estimation in retrospective studies

    PubMed Central

    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

  12. Satisfaction with and Perception of Pain Management among Palliative Patients with Breakthrough Pain: A Qualitative Study.

    PubMed

    Pathmawathi, Subramanian; Beng, Tan Seng; Li, Lee Mei; Rosli, Roshaslina; Sharwend, Supermanian; Kavitha, Rasaiah R; Christopher, Boey Chiong Meng

    2015-08-01

    Breakthrough pain is a significant contributor to much suffering by patients. The experience of intense pain may interfere with, and affect, daily life functioning and has major consequences on patients' well-being if it is not well managed. The area of breakthrough pain has not been fully understood. This study thus aimed to explore the experiences of breakthrough pain among palliative patients. A qualitative study based on a series of open-ended interviews among 21 palliative patients suffering from pain at an urban tertiary hospital in Malaysia was conducted. Five themes were generated: (i) pain viewed as an unbearable experience causing misery in the lives of patients, (ii) deterioration of body function and no hope of recovery, (iii) receiving of inadequate pain management for pain, (iv) insensitivity of healthcare providers toward patients' pain experience, and (v) pain coping experiences of patients. The findings revealed that nonpharmacologic approaches such as psychosocial support should be introduced to the patients. Proper guidance and information should be given to healthcare providers to improve the quality of patient care. Healthcare providers should adopt a sensitive approach in caring for patients' needs. The aim is to meet the needs of the patients who want to be pain free or to attain adequate relief of their pain for breakthrough pain. PMID:26256219

  13. Spared nerve injury model to study orofacial pain

    PubMed Central

    Pozza, Daniel Humberto; Castro-Lopes, José Manuel; Neto, Fani Lourença; Avelino, António

    2016-01-01

    Background & objectives: There are many difficulties in generating and testing orofacial pain in animal models. Thus, only a few and limited models that mimic the human condition are available. The aim of the present research was to develop a new model of trigeminal pain by using a spared nerve injury (SNI) surgical approach in the rat face (SNI-face). Methods: Under anaesthesia, a small incision was made in the infraorbital region of adult male Wistar rats. Three of the main infraorbital nerve branches were tightly ligated and a 2 mm segment distal to the ligation was resected. Control rats were sham-operated by exposing the nerves. Chemical hyperalgesia was evaluated 15 days after the surgery by analyzing the time spent in face grooming activity and the number of head withdrawals in response to the orofacial formalin test. Results: SNI-face rats presented a significant increase of the formalin-induced pain-related behaviours evaluated both in the acute and tonic phases (expected biphasic pattern), in comparison to sham controls. Interpretation & conclusions: The SNI-face model in the rat appears to be a valid approach to evaluate experimental trigeminal pain. Ongoing studies will test the usefulness of this model to evaluate therapeutic strategies for the treatment of orofacial pain. PMID:27241642

  14. CCR2 chemokine receptor signaling mediates pain in experimental osteoarthritis

    PubMed Central

    Miller, Rachel E.; Tran, Phuong B.; Das, Rosalina; Ghoreishi-Haack, Nayereh; Ren, Dongjun; Miller, Richard J.; Malfait, Anne-Marie

    2012-01-01

    Osteoarthritis is one of the leading causes of chronic pain, but almost nothing is known about the mechanisms and molecules that mediate osteoarthritis-associated joint pain. Consequently, treatment options remain inadequate and joint replacement is often inevitable. Here, we use a surgical mouse model that captures the long-term progression of knee osteoarthritis to longitudinally assess pain-related behaviors and concomitant changes in the innervating dorsal root ganglia (DRG). We demonstrate that monocyte chemoattractant protein (MCP)-1 (CCL2) and its high-affinity receptor, chemokine (C-C motif) receptor 2 (CCR2), are central to the development of pain associated with knee osteoarthritis. After destabilization of the medial meniscus, mice developed early-onset secondary mechanical allodynia that was maintained for 16 wk. MCP-1 and CCR2 mRNA, protein, and signaling activity were temporarily up-regulated in the innervating DRG at 8 wk after surgery. This result correlated with the presentation of movement-provoked pain behaviors, which were maintained up to 16 wk. Mice that lack Ccr2 also developed mechanical allodynia, but this started to resolve from 8 wk onwards. Despite severe allodynia and structural knee joint damage equal to wild-type mice, Ccr2-null mice did not develop movement-provoked pain behaviors at 8 wk. In wild-type mice, macrophages infiltrated the DRG by 8 wk and this was maintained through 16 wk after surgery. In contrast, macrophage infiltration was not observed in Ccr2-null mice. These observations suggest a key role for the MCP-1/CCR2 pathway in establishing osteoarthritis pain. PMID:23185004

  15. Memory and pain: tests of mood congruity and state dependent learning in experimentally induced and clinical pain.

    PubMed

    Pearce, S A; Isherwood, S; Hrouda, D; Richardson, P H; Erskine, A; Skinner, J

    1990-11-01

    The associative network theory of memory [2] is outlined along with the concepts of mood congruity and state dependent learning. Two experiments are reported which investigate the occurrence of these effects where memory for pain is concerned. In experiment 1 the performance of 25 chronic pain patients was compared with that of 25 non-patient controls on a test involving both immediate and delayed recall of a mixed list of stimulus words of 3 types: pain-related, negative or neutral. No significant group differences were found in overall rates of immediate recall. As predicted, however, pain patients recalled more pain-related words than non-patient controls (P less than 0.001). On delayed recall the same significant group x word-type interaction was obtained (P less than 0.02), but in addition the non-patient controls recalled significantly more words overall (P less than 0.02). These results provide some evidence for the occurrence of a mood congruity effect. Experiment 2 investigated state dependent learning and mood congruity effects in experimentally induced pain. Twenty volunteer subjects were allocated to 1 of 4 conditions in which a wordlist (as in experiment 1) was presented following either a painful stimulus (cold pressor test) or a non-painful one (warm water) and was then recalled immediately following further exposure to stimulus conditions which were congruent with the original stimulus (warm/warm and cold/cold conditions) or non-congruent (warm/cold and cold/warm conditions). A 3-way split plot ANOVA yielded no significant main effects for group or word-type, but a significant interaction emerged between state at encoding and at recall (P less than 0.04).(ABSTRACT TRUNCATED AT 250 WORDS)

  16. Argument for the need of investigation of the relationship between body fatness and experimental pain sensitivity.

    PubMed

    Astita, Rehab A; Tashani, Osama A; Sharp, Duncan; Johnson, Mark I

    2015-01-01

    In this communication, we argue about the need for an extensive investigation of the relationship between body fatness and fat distribution and experimental pain to explore the factors that might contribute to the increased prevalence of pain conditions in obese individuals. PMID:26085491

  17. Preclinical studies of low back pain

    PubMed Central

    2013-01-01

    Chronic low back pain is a major cause of disability and health care costs. Current treatments are inadequate for many patients. A number of preclinical models have been developed that attempt to mimic aspects of clinical conditions that contribute to low back pain. These involve application of nucleus pulposus material near the lumbar dorsal root ganglia (DRG), chronic compression of the DRG, or localized inflammation of the DRG. These models, which are primarily implemented in rats, have many common features including behavioral hypersensitivity of the hindpaw, enhanced excitability and spontaneous activity of sensory neurons, and locally elevated levels of inflammatory mediators including cytokines. Clinically, epidural injection of steroids (glucocorticoids) is commonly used when more conservative treatments fail, but clinical trials evaluating these treatments have yielded mixed results. There are relatively few preclinical studies of steroid effects in low back pain models. One preclinical study suggests that the mineralocorticoid receptor, also present in the DRG, may have pro-inflammatory effects that oppose the activation of the glucocorticoid receptor. Although the glucocorticoid receptor is the target of anti-inflammatory steroids, many clinically used steroids activate both receptors. This could be one explanation for the limited effects of epidural steroids in some patients. Additional preclinical research is needed to address other possible reasons for limited efficacy of steroids, such as central sensitization or presence of an ongoing inflammatory stimulus in some forms of low back pain. PMID:23537369

  18. Voluntary wheel running delays disease onset and reduces pain hypersensitivity in early experimental autoimmune encephalomyelitis (EAE).

    PubMed

    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. PMID:26033473

  19. Voluntary wheel running delays disease onset and reduces pain hypersensitivity in early experimental autoimmune encephalomyelitis (EAE).

    PubMed

    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.

  20. An experimental paradigm for the prediction of Post-Operative Pain (PPOP).

    PubMed

    Landau, Ruth; Kraft, John C; Flint, Lisa Y; Carvalho, Brendan; Richebé, Philippe; Cardoso, Monica; Lavand'homme, Patricia; Granot, Michal; Yarnitsky, David; Cahana, Alex

    2010-01-01

    Many women undergo cesarean delivery without problems, however some experience significant pain after cesarean section. Pain is associated with negative short-term and long-term effects on the mother. Prior to women undergoing surgery, can we predict who is at risk for developing significant postoperative pain and potentially prevent or minimize its negative consequences? These are the fundamental questions that a team from the University of Washington, Stanford University, the Catholic University in Brussels, Belgium, Santa Joana Women's Hospital in São Paulo, Brazil, and Rambam Medical Center in Israel is currently evaluating in an international research collaboration. The ultimate goal of this project is to provide optimal pain relief during and after cesarean section by offering individualized anesthetic care to women who appear to be more 'susceptible' to pain after surgery. A significant number of women experience moderate or severe acute post-partum pain after vaginal and cesarean deliveries. (1) Furthermore, 10-15% of women suffer chronic persistent pain after cesarean section. (2) With constant increase in cesarean rates in the US (3) and the already high rate in Brazil, this is bound to create a significant public health problem. When questioning women's fears and expectations from cesarean section, pain during and after it is their greatest concern. (4) Individual variability in severity of pain after vaginal or operative delivery is influenced by multiple factors including sensitivity to pain, psychological factors, age, and genetics. The unique birth experience leads to unpredictable requirements for analgesics, from 'none at all' to 'very high' doses of pain medication. Pain after cesarean section is an excellent model to study post-operative pain because it is performed on otherwise young and healthy women. Therefore, it is recommended to attenuate the pain during the acute phase because this may lead to chronic pain disorders. The impact of

  1. Genes contributing to pain sensitivity in the normal population: an exome sequencing study.

    PubMed

    Williams, Frances M K; Scollen, Serena; Cao, Dandan; Memari, Yasin; Hyde, Craig L; Zhang, Baohong; Sidders, Benjamin; Ziemek, Daniel; Shi, Yujian; Harris, Juliette; Harrow, Ian; Dougherty, Brian; Malarstig, Anders; McEwen, Robert; Stephens, Joel C; Patel, Ketan; Menni, Cristina; Shin, So-Youn; Hodgkiss, Dylan; Surdulescu, Gabriela; He, Wen; Jin, Xin; McMahon, Stephen B; Soranzo, Nicole; John, Sally; Wang, Jun; Spector, Tim D

    2012-01-01

    Sensitivity to pain varies considerably between individuals and is known to be heritable. Increased sensitivity to experimental pain is a risk factor for developing chronic pain, a common and debilitating but poorly understood symptom. To understand mechanisms underlying pain sensitivity and to search for rare gene variants (MAF<5%) influencing pain sensitivity, we explored the genetic variation in individuals' responses to experimental pain. Quantitative sensory testing to heat pain was performed in 2,500 volunteers from TwinsUK (TUK): exome sequencing to a depth of 70× was carried out on DNA from singletons at the high and low ends of the heat pain sensitivity distribution in two separate subsamples. Thus in TUK1, 101 pain-sensitive and 102 pain-insensitive were examined, while in TUK2 there were 114 and 96 individuals respectively. A combination of methods was used to test the association between rare variants and pain sensitivity, and the function of the genes identified was explored using network analysis. Using causal reasoning analysis on the genes with different patterns of SNVs by pain sensitivity status, we observed a significant enrichment of variants in genes of the angiotensin pathway (Bonferroni corrected p = 3.8×10(-4)). This pathway is already implicated in animal models and human studies of pain, supporting the notion that it may provide fruitful new targets in pain management. The approach of sequencing extreme exome variation in normal individuals has provided important insights into gene networks mediating pain sensitivity in humans and will be applicable to other common complex traits.

  2. Are Indians and females less tolerant to pain? An observational study using a laboratory pain model.

    PubMed

    Das Gupta, E; Zailinawati, A H; Lim, A W; Chan, J B; Yap, S H; Hla, Y Y; Kamil, M A; Teng, C L

    2009-06-01

    In Malaysia, it is a common belief among health care workers that females and Indians have lower pain threshold. This experience, although based on anecdotal experience in the healthcare setting, does not allow differentiation between pain tolerance, and pain expression. To determine whether there is a difference in the tolerance to pain between the three main ethnic groups, namely the Malays, Chinese and Indians as well as between males and females. This was a prospective study, using a laboratory pain model (ischaemic pain tolerance) to determine the pain tolerance of 152 IMU medical students. The mean age of the students was 21.8 years (range 18-29 years). All of them were unmarried. The median of ischaemic pain tolerance for Malays, Chinese and Indians were 639s, 695s and 613s respectively (p = 0.779). However, statistically significant difference in ischaemic pain tolerance for males and females Indian students were observed. Possible ethnic difference in pain tolerance in casual observation is not verified by this laboratory pain model. Difference in pain tolerance between genders is shown only for Indians. PMID:20058568

  3. Effects of experimentally induced low back pain on the sit-to-stand movement and electroencephalographic contingent negative variation.

    PubMed

    Jacobs, Jesse V; Yaguchi, Chie; Kaida, Chizuru; Irei, Mariko; Naka, Masami; Henry, Sharon M; Fujiwara, Katsuo

    2011-11-01

    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.

  4. Surgeons' aims and pain assessment strategies when managing paediatric post-operative pain: A qualitative study.

    PubMed

    Twycross, Alison M; Williams, Anna M; Finley, G Allen

    2015-12-01

    Children experience moderate to severe pain post-operatively. Nurses have been found to have a variety of aims in this context. Surgeons' aims when managing post-operative pain have not been explored. This qualitative study set out to explore paediatric surgeons' aims when managing post-operative pain in one paediatric hospital in Canada. Consultant surgeons (n = 8) across various specialities took part in semi-structured interviews. Surgeons' overarching aim was to keep the child comfortable. Various definitions of comfortable were given, relating to the child's experience of pain itself and their ability to undertake activities of daily living. Children's behavioural pain cues seem to be a primary consideration when making treatment decisions. Parents' views regarding their child's pain were also seen as important, suggesting children may not be seen as competent to make decisions on their own behalf. The need to maintain a realistic approach was emphasised and pain management described as a balancing act. Surgeons may draw on both tacit and explicit knowledge when assessing children's pain. There appears to be an expectation among surgeons that some pain is to be expected post-operatively and that the diagnostic value of pain may, in some cases, supersede concerns for the child's pain experience. PMID:24728398

  5. Surgeons' aims and pain assessment strategies when managing paediatric post-operative pain: A qualitative study.

    PubMed

    Twycross, Alison M; Williams, Anna M; Finley, G Allen

    2015-12-01

    Children experience moderate to severe pain post-operatively. Nurses have been found to have a variety of aims in this context. Surgeons' aims when managing post-operative pain have not been explored. This qualitative study set out to explore paediatric surgeons' aims when managing post-operative pain in one paediatric hospital in Canada. Consultant surgeons (n = 8) across various specialities took part in semi-structured interviews. Surgeons' overarching aim was to keep the child comfortable. Various definitions of comfortable were given, relating to the child's experience of pain itself and their ability to undertake activities of daily living. Children's behavioural pain cues seem to be a primary consideration when making treatment decisions. Parents' views regarding their child's pain were also seen as important, suggesting children may not be seen as competent to make decisions on their own behalf. The need to maintain a realistic approach was emphasised and pain management described as a balancing act. Surgeons may draw on both tacit and explicit knowledge when assessing children's pain. There appears to be an expectation among surgeons that some pain is to be expected post-operatively and that the diagnostic value of pain may, in some cases, supersede concerns for the child's pain experience.

  6. Imaging studies in patients with spinal pain

    PubMed Central

    Ferrari, Robert

    2016-01-01

    Abstract Objective To evaluate an a priori threshold for advanced imaging in patients with spinal pain. Design Patients with spinal pain in any region for 6 to 52 weeks were assessed to determine if radiologic studies beyond x-ray scans were indicated, including magnetic resonance imaging (MRI), computed tomography (CT), and radionuclide bone scans. An a priori threshold was set before MRI, CT, or bone scans would be considered. Those who did not have MRI, CT, or bone scans ordered were followed for at least 1 year to determine if any of them went on to be diagnosed with a more serious spinal disorder (eg, infection, fracture, spondylitis, tumour, neurologic compression). Setting Four large primary care clinics in Edmonton, Alta. Participants A total of 1003 consecutively presenting patients with symptoms suspected to be related to the spine (for a duration of generally 6 to 52 weeks) who had not already undergone advanced imaging and did not have a diagnosis of nonbenign back pain. Main outcome measures Number of cases of nonbenign spinal disorder in participants who underwent advanced imaging and participants who did not undergo advanced imaging (ie, did not have any red flags). Results There were 399 women (39.8%) and 604 men (60.2%). The mean (SD) age of the group was 47.2 (14.6) years. The mean (SD) duration of symptoms was 15.1 (8.6) weeks. Of the 1003 participants, 110 met an a priori threshold for undergoing at least 1 of MRI, CT, or bone scan. In these 110 participants, there were newly diagnosed cases of radiculopathy (n = 12), including a case of cauda equina syndrome; spondyloarthropathy (n = 6); occult fracture (n = 2); solitary metastasis (n = 1); epidural lipomatosis (n = 1); osteomyelitis (n = 1), and retroperitoneal hematoma (n = 1), each of which was considered likely to be the cause of the patient’s spinal symptoms. The remaining 893 participants were followed for at least 1 year and none showed evidence of a nonbenign cause of his or her

  7. The effect of experimental pain on motor training performance and sensorimotor integration.

    PubMed

    Dancey, Erin; Murphy, Bernadette; Srbely, John; Yielder, Paul

    2014-09-01

    Experimental pain is known to affect neuroplasticity of the motor cortex as well as motor performance, but less is known about neuroplasticity of somatosensory processing in the presence of pain. Early somatosensory evoked potentials (SEPs) provide a mechanism for investigating alterations in sensory processing and sensorimotor integration (SMI). The overall aim of this study was to investigate the interactive effects of acute pain, motor training, and sensorimotor processing. Two groups of twelve participants (N = 24) were randomly assigned to either an intervention (capsaicin cream) or placebo (inert lotion) group. SEP amplitudes were collected by stimulation of the median nerve at baseline, post-application and post-motor training. Participants performed a motor sequence task while reaction time and accuracy data were recorded. The amplitude of the P22-N24 complex was significantly increased following motor training for both groups F(2,23) = 3.533, p < 0.05, while Friedman's test for the P22-N30 complex showed a significant increase in the intervention group [χ(2) (df = 2, p = 0.016) = 8.2], with no significant change in the placebo group. Following motor training, reaction time was significantly decreased for both groups F(1,23) = 59.575, p < 0.01 and overall accuracy differed by group [χ(2) (df = 3, p < 0.001) = 19.86], with post hoc testing indicating that the intervention group improved in accuracy following motor training [χ(2) (df = 1, p = 0.001) = 11.77] while the placebo group had worse accuracy [χ(2) (df = 1, p = 0.006) = 7.67]. The improved performance in the presence of capsaicin provides support for the enhancement of knowledge acquisition with the presence of nontarget stimuli. In addition, the increase in SEP peak amplitudes suggests that early SEP changes are markers of SMI changes accompanying motor training and acute pain.

  8. Heritability of responses to painful stimuli in women: a classical twin study.

    PubMed

    Norbury, Timothy A; MacGregor, Alex J; Urwin, Jane; Spector, Tim D; McMahon, Stephen B

    2007-11-01

    There is as yet no conclusive evidence for the heritability of pain sensitivity in humans. We performed a classical twin study to evaluate the relative contributions of genetic and environmental factors on responses to painful stimuli in women. Ninety-eight pairs of twins, 51 monozygotic (MZ) and 47 dizygotic (DZ), were recruited from the TwinsUK adult registry held at St Thomas' Hospital, London. The correlation of quantitative sensory testing scores for the different responses to painful stimuli were compared between the MZ and DZ twin pairs and structural equation modelling was used to provide an estimate of the heritability. Statistically significant genetic components (varying between 22 and 55%) were seen for the responses to the majority of painful stimuli including: heat pain threshold (HPT), the pain rating during induction of a thermal burn, the secondary areas of punctate hyperalgesia and brush evoked allodynia following the induction of a 45 degrees C thermal burn, and the pain ratings during the iontophoresis of adenosine triphosphate (ATP) and acid. The area of skin flare following thermal burn induction did not have a significant genetic component; rather common environmental factors provided the greatest contribution (65%). In our experiment neither shared genetic nor environmental features were significant in determining the extent of thermal sensitisation. In summary we show that sensitivity to a variety of experimental thermal, mechanical and chemical pain-producing stimuli has a genetic contribution. Our study demonstrates the importance of genetic factors in determining human experimental pain sensitivity, and opens the way for its use as a phenotype in gene discovery. Since experimental pain sensitivity is known to be a predictor for pathological pain, our data imply that genetic factors have an important aetiological contribution towards clinical pain states. PMID:17932101

  9. Case study: the painful os trigonum syndrome.

    PubMed

    Brown, G P; Feehery, R V; Grant, S M

    1995-07-01

    The painful os trigonum syndrome is one cause of posterolateral ankle pain. This syndrome is most prevalent in athletes who perform frequent and/or forceful plantar flexion. The painful os trigonum may be misdiagnosed as Achilles and/or peroneal tendinitis. In this case, the patient was misdiagnosed for 15 months and treated for tendinitis. The appropriate clinical tests to evaluate the os trigonum as a source of posterolateral ankle pain are outlined. The surgical and postoperative management for the patient are discussed. Clinicians should be aware of the painful os trigonum syndrome as a possible source of posterolateral ankle pain.

  10. High- and low-frequency transcutaneous electrical nerve stimulation does not reduce experimental pain in elderly individuals

    PubMed Central

    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

  11. High- and low-frequency transcutaneous electrical nerve stimulation does not reduce experimental pain in elderly individuals.

    PubMed

    Bergeron-Vézina, Kayla; Corriveau, Hélène; Martel, Marylie; Harvey, Marie-Philippe; Léonard, Guillaume

    2015-10-01

    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.

  12. Burn patients' experience of pain management: a qualitative study.

    PubMed

    Yuxiang, Li; Lingjun, Zhou; Lu, Tang; Mengjie, Liu; Xing, Ming; Fengping, Shen; Jing, Cui; Xianli, Meng; Jijun, Zhao

    2012-03-01

    Pain is a major problem after burns and researchers continue to report that pain from burns remains undertreated. The inadequate pain control results in adverse sequalae physically and psychologically in the burn victims. A better understanding of a burn patient's experience is important in identifying the factors responsible for undertreated pain and establishing effective pain management guidelines or recommendation in the practice of pain relief for burn injuries. This study sought to explore and describe the experience that patients have about pain related to burn-injury during hospitalization. Semi-structured interviews were conducted on eight patients with moderate to severe pain from burn injuries recruited from a Burn Centre in Northwest China. Data was collected by in-depth interviews and qualitative description after full transcription of each interview. Analysis involved the identification of themes and the development of a taxonomy of patients' experience of burn pain and its management. Three themes were indentified: (1) patients' experience of pain control, (2) patients' perception on burn pain management, and (3) patients' expectation of burn pain management. Findings from this study suggested that patients experience uncontrolled pain both physically and psychologically which may serve as an alert for awareness of health professionals to recognize and establish a multidisciplinary pain management team for burn victims, including surgeons, critical care specialists, anesthesiologists, nurses, psychologists, and social workers to accomplish safe and effective strategies for pain control to reach an optimal level of pain management in burn patients. It also provides insights and suggestions for future research directions to address this significant clinical problem.

  13. Pain perception and hypnosis: findings from recent functional neuroimaging studies.

    PubMed

    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. PMID:25719519

  14. Sensory Re-Weighting in Human Bipedal Postural Control: The Effects of Experimentally-Induced Plantar Pain.

    PubMed

    Pradels, Antoine; Pradon, Didier; Hlavačková, Petra; Diot, Bruno; Vuillerme, Nicolas

    2013-01-01

    The present study was designed to assess the effects of experimentally-induced plantar pain on the displacement of centre of foot pressure during unperturbed upright stance in different sensory conditions of availability and/or reliability of visual input and somatosensory input from the vestibular system and neck. To achieve this goal, fourteen young healthy adults were asked to stand as still as possible in three sensory conditions: (1) No-vision, (2) Vision, and (3) No-vision - Head tilted backward, during two experimental conditions: (1) a No-pain condition, and (2) a condition when a painful stimulation was applied to the plantar surfaces of both feet (Plantar-pain condition). Centre of foot pressure (CoP) displacements were recorded using a force platform. Results showed that (1) experimentally-induced plantar pain increased CoP displacements in the absence of vision (No-vision condition), (2) this deleterious effect was more accentuated when somatosensory information from the vestibular and neck was altered (No-vision - Head tilted backward condition) and (3) this deleterious effect was suppressed when visual information was available (Vision condition). From a fundamental point of view, these results lend support to the sensory re-weighting hypothesis whereby the central nervous system dynamically and selectively adjusts the relative contributions of sensory inputs (i.e. the sensory weightings) in order to maintain balance when one or more sensory channels are altered by the task (novel or challenging), environmental or individual conditions. From a clinical point of view, the present findings further suggest that prevention and treatment of plantar pain may be relevant for the preservation or improvement of balance control, particularly in situations (or individuals) in which information provided by the visual, neck proprioceptive and vestibular systems is unavailable or disrupted. PMID:23840337

  15. Sensory Re-Weighting in Human Bipedal Postural Control: The Effects of Experimentally-Induced Plantar Pain

    PubMed Central

    Pradels, Antoine; Pradon, Didier; Hlavačková, Petra; Diot, Bruno; Vuillerme, Nicolas

    2013-01-01

    The present study was designed to assess the effects of experimentally-induced plantar pain on the displacement of centre of foot pressure during unperturbed upright stance in different sensory conditions of availability and/or reliability of visual input and somatosensory input from the vestibular system and neck. To achieve this goal, fourteen young healthy adults were asked to stand as still as possible in three sensory conditions: (1) No-vision, (2) Vision, and (3) No-vision – Head tilted backward, during two experimental conditions: (1) a No-pain condition, and (2) a condition when a painful stimulation was applied to the plantar surfaces of both feet (Plantar-pain condition). Centre of foot pressure (CoP) displacements were recorded using a force platform. Results showed that (1) experimentally-induced plantar pain increased CoP displacements in the absence of vision (No-vision condition), (2) this deleterious effect was more accentuated when somatosensory information from the vestibular and neck was altered (No-vision – Head tilted backward condition) and (3) this deleterious effect was suppressed when visual information was available (Vision condition). From a fundamental point of view, these results lend support to the sensory re-weighting hypothesis whereby the central nervous system dynamically and selectively adjusts the relative contributions of sensory inputs (i.e. the sensory weightings) in order to maintain balance when one or more sensory channels are altered by the task (novel or challenging), environmental or individual conditions. From a clinical point of view, the present findings further suggest that prevention and treatment of plantar pain may be relevant for the preservation or improvement of balance control, particularly in situations (or individuals) in which information provided by the visual, neck proprioceptive and vestibular systems is unavailable or disrupted. PMID:23840337

  16. Pelvic organ cross-sensitization to enhance bladder and urethral pain behaviors in rats with experimental colitis.

    PubMed

    Yoshikawa, S; Kawamorita, N; Oguchi, T; Funahashi, Y; Tyagi, P; Chancellor, M B; Yoshimura, N

    2015-01-22

    Neural cross-sensitization has been postulated as a mechanism underlying overlaps of chronic pelvic pain disorders such as bladder pain syndrome/interstitial cystitis (BPS/IC) and irritable bowel syndrome (IBS). Animals with experimental colitis have been used to study the underlying mechanisms for overlapped pelvic pain symptoms, and shown to exhibit bladder overactivity evidenced by frequent voiding; however, it has not directly been evaluated whether pain sensation derived from the lower urinary tract is enhanced in colitis models. Also, the cross-sensitization between the colon and urethra has not been studied previously. In the present study, we therefore investigated pain behaviors induced by nociceptive stimuli in the lower urinary tract and the involvement of C-fiber afferent pathways using rats with colitis induced by intracolonic application of 2,4,6-trinitrobenzenesulfonic acid (TNBS). In TNBS-induced colitis rats at 10 days, intravesical application of resiniferatoxin (RTx) induced a significantly greater number of episodes of both licking and freezing behaviors, which were reduced by capsaicin-sensitive C-fiber afferent desensitization. Histochemical studies using fluorescent dye tracers injected into the colon, bladder or urethra showed that dichotomized afferent neurons comprised 6.9-14.5% of L1, L6 and S1 dorsal root ganglion (DRG) neurons innervating the colon or the lower urinary tract. Transient receptor potential vanilloid 1 (TRPV1) mRNA expression was significantly increased in, the bladder, urethra and S1 DRG in colitis rats. An increase in myeloperoxidase (MPO) activity was found in the colon, but not in the bladder or urethra after intracolonic TNBS treatment. These results indicate that TNBS-induced colitis increased pain sensitivity in the bladder and urethra via activation of C-fiber afferent pathways due to colon-to-bladder and colon-to-urethral cross-sensitization, suggesting the contribution of pelvic organ cross

  17. Pelvic pain after childbirth: a longitudinal population study.

    PubMed

    Bjelland, Elisabeth Krefting; Owe, Katrine Mari; Pingel, Ronnie; Kristiansson, Per; Vangen, Siri; Eberhard-Gran, Malin

    2016-03-01

    In this longitudinal population study, the aims were to study associations of mode of delivery with new onset of pelvic pain and changes in pelvic pain scores up to 7 to 18 months after childbirth. We included 20,248 participants enrolled in the Norwegian Mother and Child Cohort Study (1999-2008) without preexisting pelvic pain in pregnancy. Data were obtained by 4 self-administered questionnaires and linked to the Medical Birth Registry of Norway. A total of 4.5% of the women reported new onset of pelvic pain 0 to 3 months postpartum. Compared to unassisted vaginal delivery, operative vaginal delivery was associated with increased odds of pelvic pain (adjusted odds ratio [OR]: 1.30; 95% confidence interval [CI]: 1.06-1.59). Planned and emergency cesarean deliveries were associated with reduced odds of pelvic pain (adjusted OR: 0.48; 95% CI: 0.31-0.74 and adjusted OR: 0.65; 95% CI: 0.49-0.87, respectively). Planned cesarean delivery, young maternal age, and low Symptom Checklist-8 scores were associated with low pelvic pain scores after childbirth. A history of pain was the only factor associated with increased pelvic pain scores over time (P = 0.047). We conclude that new onset of pelvic pain after childbirth was not commonly reported, particularly following cesarean delivery. Overall, pelvic pain scores were rather low at all time points and women with a history of pain reported increased pelvic pain scores over time. Hence, clinicians should follow up women with pelvic pain after a difficult childbirth experience, particularly if they have a history of pain. PMID:26588694

  18. Pelvic pain after childbirth: a longitudinal population study.

    PubMed

    Bjelland, Elisabeth Krefting; Owe, Katrine Mari; Pingel, Ronnie; Kristiansson, Per; Vangen, Siri; Eberhard-Gran, Malin

    2016-03-01

    In this longitudinal population study, the aims were to study associations of mode of delivery with new onset of pelvic pain and changes in pelvic pain scores up to 7 to 18 months after childbirth. We included 20,248 participants enrolled in the Norwegian Mother and Child Cohort Study (1999-2008) without preexisting pelvic pain in pregnancy. Data were obtained by 4 self-administered questionnaires and linked to the Medical Birth Registry of Norway. A total of 4.5% of the women reported new onset of pelvic pain 0 to 3 months postpartum. Compared to unassisted vaginal delivery, operative vaginal delivery was associated with increased odds of pelvic pain (adjusted odds ratio [OR]: 1.30; 95% confidence interval [CI]: 1.06-1.59). Planned and emergency cesarean deliveries were associated with reduced odds of pelvic pain (adjusted OR: 0.48; 95% CI: 0.31-0.74 and adjusted OR: 0.65; 95% CI: 0.49-0.87, respectively). Planned cesarean delivery, young maternal age, and low Symptom Checklist-8 scores were associated with low pelvic pain scores after childbirth. A history of pain was the only factor associated with increased pelvic pain scores over time (P = 0.047). We conclude that new onset of pelvic pain after childbirth was not commonly reported, particularly following cesarean delivery. Overall, pelvic pain scores were rather low at all time points and women with a history of pain reported increased pelvic pain scores over time. Hence, clinicians should follow up women with pelvic pain after a difficult childbirth experience, particularly if they have a history of pain.

  19. Pain-related fear predicts reduced spinal motion following experimental back injury.

    PubMed

    Trost, Zina; France, Christopher R; Sullivan, Michael J; Thomas, James S

    2012-05-01

    The current study examined the prospective relationship between pain-related fear and altered motor behavior, as well as perceived interference, among 51 healthy participants following induction of delayed-onset muscle soreness (DOMS) to the trunk extensor muscles. Healthy participants without history of back pain completed standardized reaches to high and low targets at self-paced and rapid speeds before and after induction of acute low back pain using a DOMS paradigm. Pain-related fear was assessed prior to DOMS induction. Three-dimensional joint motions of the thoracic spine, lumbar spine, and hip were recorded using an electromagnetic tracking device. DOMS-induced differences between high- and low-fear participants were observed for lumbar spine flexion, but not for thoracic or hip flexion. Pain-related fear scores were not predictive of lumbar flexion during baseline, but predicted reduced lumbar flexion during self- and fast-paced trials to low target locations once DOMS was induced. Pain-related fear was likewise predictive of perceived interference in life activities following DOMS induction. The findings suggest that initially pain-free individuals with high pain-related fear adopt avoidant spinal strategies during common reaching movements shortly after injury is sustained, which may comprise a risk factor for future pain and disability. PMID:22377437

  20. The Effects of Experimentally Induced Low Back Pain on Spine Rotational Stiffness and Local Dynamic Stability.

    PubMed

    Ross, Gwyneth B; Mavor, Matthew; Brown, Stephen H M; Graham, Ryan B

    2015-09-01

    Local dynamic stability, quantified using the maximum finite-time Lyapunov exponent (λ max), and the muscular contributions to spine rotational stiffness can provide pertinent information regarding the neuromuscular control of the spine during movement tasks. The primary goal of the present study was to assess if experimental capsaicin-induced low back pain (LBP) affects spine stability and the neuromuscular control of repetitive trunk movements in a group of healthy participants with no history of LBP. Fourteen healthy males were recruited for this investigation. Each participant was asked to complete three trials (baseline, in pain, and recovery) of 35 cycles of a repetitive trunk flexion/extension task at a rate of 0.25 Hz. Local dynamic stability and the muscular contributions to lumbar spine rotational stiffness were significantly impaired during the LBP trial compared to the baseline trial (p < 0.05); however, there was a trend for these measures to recover after a 1 h rest. This study provides evidence that capsaicin can effectively induce LBP, thereby altering spine rotational stiffness and local dynamic stability. Future research should directly compare the effects capsaicin-induced LBP and intramuscular/intraligamentous induced LBP on these same variables.

  1. Reorganization of muscle synergies during multidirectional reaching in the horizontal plane with experimental muscle pain

    PubMed Central

    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

  2. Duration of Analgesia Induced by Acupuncture-Like TENS on Experimental Heat Pain

    PubMed Central

    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. PMID:27335882

  3. Effect of Catechol-O-methyltransferase-gene (COMT) Variants on Experimental and Acute Postoperative Pain in 1,000 Women undergoing Surgery for Breast Cancer

    PubMed Central

    Kambur, Oleg; Kaunisto, Mari A.; Tikkanen, Emmi; Leal, Suzanne M.; Ripatti, Samuli; Kalso, Eija A.

    2016-01-01

    Background Catechol-O-methyltransferase (COMT) metabolizes catecholamines in different tissues. Polymorphisms in COMT gene can attenuate COMT activity and increase sensitivity to pain. Human studies exploring the effect of COMT polymorphisms on pain sensitivity have mostly included small, heterogeneous samples and have ignored several important single nucleotide polymorphisms (SNPs). This study examines the effect of COMT polymorphisms on experimental and postoperative pain phenotypes in a large ethnically homogeneous female patient cohort. Methods Intensity of cold (+2–4°C) and heat (+48°C) pain and tolerance to cold pain were assessed in 1,000 patients scheduled for breast cancer surgery. Acute postoperative pain and oxycodone requirements were recorded. Twenty-two COMT SNPs were genotyped and their association with six pain phenotypes analyzed with linear regression. Results There was no association between any of the tested pain phenotypes and SNP rs4680. The strongest association signals were seen between rs165774 and heat pain intensity as well as rs887200 and cold pain intensity. In both cases, minor allele carriers reported less pain. Neither of these results remained significant after strict multiple testing corrections. When analyzed further, the effect of rs887200 was, however, shown to be significant and consistent throughout the cold pressure test. No evidence of association between the SNPs and postoperative oxycodone consumption was found. Conclusions SNPs rs887200 and rs165774 located in the untranslated regions of the gene had the strongest effects on pain sensitivity. Their effect on pain is described here for the first time. These results should be confirmed in further studies and the potential functional mechanisms of the variants studied. PMID:24343288

  4. Pain anticipatory phenomena in patients with central poststroke pain: a magnetoencephalography study.

    PubMed

    Gopalakrishnan, Raghavan; Burgess, Richard C; Lempka, Scott F; Gale, John T; Floden, Darlene P; Machado, Andre G

    2016-09-01

    Central poststroke pain (CPSP) is characterized by hemianesthesia associated with unrelenting chronic pain. The final pain experience stems from interactions between sensory, affective, and cognitive components of chronic pain. Hence, managing CPSP will require integrated approaches aimed not only at the sensory but also the affective-cognitive spheres. A better understanding of the brain's processing of pain anticipation is critical for the development of novel therapeutic approaches that target affective-cognitive networks and alleviate pain-related disability. We used magnetoencephalography (MEG) to characterize the neural substrates of pain anticipation in patients suffering from intractable CPSP. Simple visual cues evoked anticipation while patients awaited impending painful (PS), nonpainful (NPS), or no stimulus (NOS) to their nonaffected and affected extremities. MEG responses were studied at gradiometer level using event-related fields analysis and time-frequency oscillatory analysis upon source localization. On the nonaffected side, significantly greater responses were recorded during PS. PS (vs. NPS and NOS) exhibited significant parietal and frontal cortical activations in the beta and gamma bands, respectively, whereas NPS (vs. NOS) displayed greater activation in the orbitofrontal cortex. On the affected extremity, PS (vs. NPS) did not show significantly greater responses. These data suggest that anticipatory phenomena can modulate neural activity when painful stimuli are applied to the nonaffected extremity but not the affected extremity in CPSP patients. This dichotomy may stem from the chronic effects of pain on neural networks leading to habituation or saturation. Future clinically effective therapies will likely be associated with partial normalization of the neurophysiological correlates of pain anticipation. PMID:27358316

  5. 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

  6. Continuous neurophatic orofacial pain: A retrospective study of 23 cases

    PubMed Central

    Sotorra-Figuerola, Dídac; Sánchez-Torres, Alba; Valmaseda-Castellón, Eduard

    2016-01-01

    Background 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. Material and Methods 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. Results 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. Conclusions 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. Key words:Continuous neuropathic orofacial pain, persistent idiopathic facial pain, painful post-traumatic trigeminal neuropathy

  7. Racial bias in pain perception and response: experimental examination of automatic and deliberate processes

    PubMed Central

    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

  8. Conditioned Pain Modulation and Situational Pain Catastrophizing as Preoperative Predictors of Pain following Chest Wall Surgery: A Prospective Observational Cohort Study

    PubMed Central

    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

  9. Pilot study of a compassion meditation intervention in chronic pain

    PubMed Central

    Chapin, Heather L; Darnall, Beth D; Seppala, Emma M; Doty, James R; Hah, Jennifer M; Mackey, Sean C

    2016-01-01

    Background The emergence of anger as an important predictor of chronic pain outcomes suggests that treatments that target anger may be particularly useful within the context of chronic pain. Eastern traditions prescribe compassion cultivation to treat persistent anger. Compassion cultivation has been shown to influence emotional processing and reduce negativity bias in the contexts of emotional and physical discomfort, thus suggesting it may be beneficial as a dual treatment for pain and anger. Our objective was to conduct a pilot study of a 9-week group compassion cultivation intervention in chronic pain to examine its effect on pain severity, anger, pain acceptance and pain-related interference. We also aimed to describe observer ratings provided by patients’ significant others and secondary effects of the intervention. Methods Pilot clinical trial with repeated measures design that included a within-subjects wait-list control period. Twelve chronic pain patients completed the intervention (F= 10). Data were collected from patients at enrollment, treatment baseline and post-treatment; participant significant others contributed data at the enrollment and post-treatment time points. Results In this predominantly female sample, patients had significantly reduced pain severity and anger and increased pain acceptance at post-treatment compared to treatment baseline. Significant other qualitative data corroborated patient reports for reductions in pain severity and anger. Conclusions Compassion meditation may be a useful adjunctive treatment for reducing pain severity and anger, and for increasing chronic pain acceptance. Patient reported reductions in anger were corroborated by their significant others. The significant other corroborations offer a novel contribution to the literature and highlight the observable emotional and behavioral changes in the patient participants that occurred following the compassion intervention. Future studies may further examine how

  10. Independent psychophysical measurement of experimental modulations in the somatotopy of cutaneous heat-pain stimuli.

    PubMed

    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.

  11. Current pain education within undergraduate medical studies across Europe: Advancing the Provision of Pain Education and Learning (APPEAL) study

    PubMed Central

    Briggs, Emma V; Battelli, Daniele; Gordon, David; Kopf, Andreas; Ribeiro, Sofia; Puig, Margarita M; Kress, Hans G

    2015-01-01

    Objectives 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. Design and methods 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. Results 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. Conclusions Documented pain teaching in many European medical schools falls far short of what might be expected given the

  12. Factors associated with increased risk for pain catastrophizing in patients with chronic neck pain: A retrospective cross-sectional study.

    PubMed

    Park, Sang Jun; Lee, Rippy; Yoon, Duck Mi; Yoon, Kyung Bong; Kim, Kiwook; Kim, Shin Hyung

    2016-09-01

    Pain catastrophizing is becoming increasingly recognized as a clinically important psychological factor in chronic musculoskeletal pain. In this retrospective cross-sectional study, we have identified factors associated with an increased risk for pain catastrophizing in chronic neck pain (CNP) patients. We obtained data from our medical database on 331 patients who were treated for neck pain as their chief complaint at our clinic. The Pain Catastrophizing Scale (PCS) was used to define a high pain catastrophizing state (PCS score ≥21) in this study. Patient demographics, pain-related factors, and psychological factors were evaluated with logistic regression analysis to identify risk factors of high pain catastrophizing among patients with CNP. A total of 256 patients with CNP satisfied the study inclusion criteria and were included in the analyses. The median PCS score was 16 (range, 0-45), and 86 of 256 patients (33.5%) reported a PCS score ≥21. In multivariate analysis, high pain intensity, clinical insomnia, and a high level of depression/anxiety were strongly associated with high pain catastrophizing in patients with CNP. Depression was the strongest predictor of high pain catastrophizing, with an odds ratio of 7.35 (95% confidence interval 2.23-24.22). High pain catastrophizing was not significantly related to age, gender, comorbidities, or neck pain-related physical symptoms. In conclusion, poor psychological states should be addressed as an important part of pain management in CNP patients who are susceptible to high pain catastrophizing. PMID:27631217

  13. [Pathophysiology of neuropathic pain: review of experimental models and proposed mechanisms].

    PubMed

    Garcia-Larrea, Luis; Magnin, Michel

    2008-02-01

    Neuropathic pain can be conceptualized as the result of an "aberrant learning" process, associated with maladaptive plasticity of the nervous system. A number of modifications of the peripheral nervous system have been described in animal models of neuropathic pain, but their relation with different symptoms in humans is far from fully understood. We note in particular ectopic discharges in damaged myelinated fibers, abnormal activity in undamaged fibers, overexpression of calcium channels increasing the release of excitatory neurotransmitters, and sympathetic sprouting towards the spinal ganglia. Spinal mechanisms involve central sensitization, kindling and potentiation phenomena. Underlying these phenomena may be connectivity changes--still controversial--of non-nociceptive terminals and variations in the sensitivity of postsynaptic receptors. Also contributing to these pathophysiologic modifications are attenuation of spinal inhibition by selective neuronal loss and the development of inflammatory phenomena, including cytokine secretion by macrophages and glial cells. Changes in the dorsal horn modify the activity of projections towards the brainstem and increase spinal hyperactivity still further by feedback loops. These effects are delayed, suggesting that maintenance of spinal sensitization requires the involvement of mechanisms of descending facilitation involving the brainstem. These phenomena induce changes in the activity of thalamocortical networks, which develop autonomous processes that maintain the pain. The cortical representation of body areas change after nervous lesions, and these changes may correlate with the emergence of pain. Neuropathic allodynia and hyperalgesia are supported by cortical modifications that experimental models reproduce very incompletely. Experimental allodynia and neuropathic allodynia share the activation of the cortical pain matrix as well as the bilateralization of insular activity. However, although experimental

  14. An Epidemiological Study of Neuropathic Pain Symptoms in Canadian Adults

    PubMed Central

    VanDenKerkhof, Elizabeth G.; Mann, Elizabeth G.; Torrance, Nicola; Smith, Blair H.; Johnson, Ana; Gilron, Ian

    2016-01-01

    The reported prevalence of neuropathic pain ranges from 6.9% to 10%; however the only Canadian study reported 17.9%. The objective of this study was to describe the epidemiology of neuropathic pain in Canada. A cross-sectional survey was conducted in a random sample of Canadian adults. The response rate was 21.1% (1504/7134). Likely or possible neuropathic pain was defined using a neuropathic pain-related diagnosis and a positive outcome on the Self-Report Leeds Assessment of Neuropathic Symptoms and Signs pain scale (S-LANSS) or the Douleur Neuropathique 4 (DN4) Questions. The prevalence of likely neuropathic pain was 1.9% (S-LANSS) and 3.4% (DN4) and that of possible neuropathic pain was 5.8% (S-LANSS) and 8.1% (DN4). Neuropathic pain was highest in economically disadvantaged males. There is a significant burden of neuropathic pain in Canada. The low response rate and a slightly older and less educated sample than the Canadian population may have led to an overestimate of neuropathic pain. Population prevalence varies by screening tool used, indicating more work is needed to develop reliable measures. Population level screening targeted towards high risk groups should improve the sensitivity and specificity of screening, while clinical examination of those with positive screening results will further refine the estimate of prevalence. PMID:27445636

  15. The TARGET pain study: Lessons from a painful marathon.

    PubMed

    Thom, Ogilvie N; Keijzers, Gerben; Taylor, David McD; Fatovich, Daniel M; Finucci, Daniel P; Furyk, Jeremy; Jin, Sang-Won; Macdonald, Stephen Pj; Mitenko, Hugh Ma; Richardson, Joanna R; Ting, Joseph Ys; Gibbs, Clinton R; Chalkley, Dane R

    2016-10-01

    This perspective article summarises the experience of conducting a multicentre research project. We describe expected and unexpected hurdles we experienced as well as suggesting possible solutions for researchers embarking on multicentre studies. PMID:27346063

  16. The TARGET pain study: Lessons from a painful marathon.

    PubMed

    Thom, Ogilvie N; Keijzers, Gerben; Taylor, David McD; Fatovich, Daniel M; Finucci, Daniel P; Furyk, Jeremy; Jin, Sang-Won; Macdonald, Stephen Pj; Mitenko, Hugh Ma; Richardson, Joanna R; Ting, Joseph Ys; Gibbs, Clinton R; Chalkley, Dane R

    2016-10-01

    This perspective article summarises the experience of conducting a multicentre research project. We describe expected and unexpected hurdles we experienced as well as suggesting possible solutions for researchers embarking on multicentre studies.

  17. Hypnotherapy of a pain disorder: a clinical case study.

    PubMed

    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. PMID:25719524

  18. Intensive interdisciplinary outpatient pain management program for chronic back pain: a pilot study

    PubMed Central

    Artner, Juraj; Kurz, Stephan; Cakir, Balkan; Reichel, Heiko; Lattig, Friederike

    2012-01-01

    Background Chronic back pain is relatively resistant to unimodal therapy regimes. The aim of this study was to introduce and evaluate the short-term outcome of a three-week intensive multidisciplinary outpatient program for patients with back pain and sciatica, measured according to decrease of functional impairment and pain. Methods The program was designed for patients suffering from chronic back pain to provide intensive interdisciplinary therapy in an outpatient setting, consisting of interventional injection techniques, medication, exercise therapy, back education, ergotherapy, traction, massage therapy, medical training, transcutaneous electrical nerve stimulation, aquatraining, and relaxation. Results Based on Oswestry Disability Index (ODI) and Numeric Rating Scale (NRS) scores, a significant improvement in pain intensity and functionality of 66.83% NRS and an ODI of 33.33% were achieved by our pain program within 3 weeks. Conclusion This paper describes the organization and short-term outcome of an intensive multidisciplinary program for chronic back pain on an outpatient basis provided by our orthopedic department, with clinically significant results. PMID:22826641

  19. Guidelines on the recognition of pain, distress and discomfort in experimental animals and an hypothesis for assessment.

    PubMed

    Morton, D B; Griffiths, P H

    1985-04-20

    Under the 1876 Cruelty to Animals Act it is necessary to recognise pain so that an assessment may be made to determine if it is 'an experiment calculated to give pain' and 'to prevent the animal feeling pain'. Under the conditions of the licence it is also necessary to recognise 'severe pain which is likely to endure' and 'suffering considerable pain'. In the White Paper May 1983 (Command 8883) it is stated that: 'in the application of controls the concept of pain should be applied in a wide sense' and 'the Home Secretary's practice has been to interpret the concept of pain to include disease, other disturbances of normal health, adverse change in physiology, discomfort and distress'. The draft European Convention for the Protection of Vertebrate Animals used for Experimental and other Purposes, aims to control, subject to specific exceptions, any experimental or other scientific procedure which 'may cause pain, suffering, distress or lasting harm'. (The White Paper states that UK control will be stricter than the Council of Europe proposals.) Thus, there is a considerable onus on the experimenter to recognise pain (not to define it) and to alleviate it. It is intended that this article should be of help, not only to newcomers inexperienced in the recognition of pain, but also possibly to those relatively experienced workers who may be called upon to evaluate the pain involved in a new model or an individual animal.(ABSTRACT TRUNCATED AT 250 WORDS)

  20. Experimental Muscle Pain Impairs the Synergistic Modular Control of Neck Muscles.

    PubMed

    Gizzi, Leonardo; Muceli, Silvia; Petzke, Frank; Falla, Deborah

    2015-01-01

    A motor task can be performed via different patterns of muscle activation that show regularities that can be factorized in combinations of a reduced number of muscle groupings (also referred to as motor modules, or muscle synergies). In this study we evaluate whether an acute noxious stimulus induces a change in the way motor modules are combined to generate movement by neck muscles. The neck region was selected as it is a region with potentially high muscular redundancy. We used the motor modules framework to assess the redistribution of muscular activity of 12 muscles (6 per side) in the neck region of 8 healthy individuals engaged in a head and neck aiming task, in non-painful conditions (baseline, isotonic saline injection, post pain) and after the injection of hypertonic saline into the right splenius capitis muscle. The kinematics of the task was similar in the painful and control conditions. A general decrease of activity was noted for the injected muscle during the painful condition together with an increase or decrease of the activity of the other muscles. Subjects did not adopt shared control strategies (motor modules inter subject similarity at baseline 0.73±0.14); the motor modules recorded during the painful condition could not be used to reconstruct the activation patterns of the control conditions, and the painful stimulus triggered a subject-specific redistribution of muscular activation (i.e., in some subjects the activity of a given muscle increased, whereas in other subjects it decreased with pain). Alterations of afferent input (i.e., painful stimulus) influenced motor control at a multi muscular level, but not kinematic output. These findings provide new insights into the motor adaptation to pain.

  1. Experimental Muscle Pain Impairs the Synergistic Modular Control of Neck Muscles

    PubMed Central

    Gizzi, Leonardo; Muceli, Silvia; Petzke, Frank; Falla, Deborah

    2015-01-01

    A motor task can be performed via different patterns of muscle activation that show regularities that can be factorized in combinations of a reduced number of muscle groupings (also referred to as motor modules, or muscle synergies). In this study we evaluate whether an acute noxious stimulus induces a change in the way motor modules are combined to generate movement by neck muscles. The neck region was selected as it is a region with potentially high muscular redundancy. We used the motor modules framework to assess the redistribution of muscular activity of 12 muscles (6 per side) in the neck region of 8 healthy individuals engaged in a head and neck aiming task, in non-painful conditions (baseline, isotonic saline injection, post pain) and after the injection of hypertonic saline into the right splenius capitis muscle. The kinematics of the task was similar in the painful and control conditions. A general decrease of activity was noted for the injected muscle during the painful condition together with an increase or decrease of the activity of the other muscles. Subjects did not adopt shared control strategies (motor modules inter subject similarity at baseline 0.73±0.14); the motor modules recorded during the painful condition could not be used to reconstruct the activation patterns of the control conditions, and the painful stimulus triggered a subject-specific redistribution of muscular activation (i.e., in some subjects the activity of a given muscle increased, whereas in other subjects it decreased with pain). Alterations of afferent input (i.e., painful stimulus) influenced motor control at a multi muscular level, but not kinematic output. These findings provide new insights into the motor adaptation to pain. PMID:26382606

  2. Toll-like Receptor 4 and Comorbid Pain in Interstitial Cystitis/Bladder Pain Syndrome: A Multidisciplinary Approach to the Study of Chronic Pelvic Pain Research Network Study

    PubMed Central

    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

  3. Study of Patient Pain Management after Heart Surgery

    PubMed Central

    Sattari, Mohammadreza; Baghdadchi, Mohammad Ebrahim; Kheyri, Marzieh; Khakzadi, Hassan; Ozar Mashayekhi, Simin

    2013-01-01

    Purpose: To investigate postoperative pain control and analgesic use after heart surgery. Methods: 20 patients undergone heart surgery, randomly entered the study. Each patient was asked to score his pain intensity on visual analog scale (VAS) at four different occasions. Results: 120 patients aged 59 year-old; including 81 male were enrolled in the study. 69.2% had coronary artery disease and 16.7% had heart-valve problem. Main types of surgeries were coronary artery bypass surgery (70.5%) and valve repairement (23%). Duration of ICU stay was 4.78±2.7 days and duration of intubations was 17.38 ± 36.46 hours. Pre-surgery pain relief was administrated to 42% of the subjects and morphine and promethazine was the main pre-surgery analgesia medication. Post surgery analgesic included morphine (injection), petidine (injection) and NSAIDS (oral or rectal). According to VAS, mean pain level, 1 and 4 hours after extubation, and before and one hour after transferring to wards was 5.05±2.5, 4.09±2.0, 3.52±1.8, 2.36±1.89, respectively. Although the level of pain reported was mostly moderate, 80% were reported satisfaction with their post-surgery pain management. Conclusion: A closer pain management control is needed for patients after heart surgery. Introduction of newer pain management techniques, medications and dosages could reduce the pain and suffering. PMID:24312863

  4. Analgesic effects of transcutaneous electrical nerve stimulation and interferential current on experimental ischemic pain models: frequencies of 50 hz and 100 hz.

    PubMed

    Bae, Young-Hyeon; Lee, Suk Min

    2014-12-01

    [Purpose] This study compared the analgesic effects of transcutaneous electrical nerve stimulation (TENS) and interferential currents (IFC) on induced ischemic pain in healthy volunteers. [Subjects] The subjects were 36 volunteers (18 male, 18 female) without known pathology that could cause pain. Their mean age was 24.5±2.2 years. [Methods] A single-blind and parallel-group method was used. Subjects were randomly allocated to receive each 50 Hz TENS, 50 Hz IFC, 100 Hz TENS, and 100 Hz IFC. This study experimentally induced ischemic pain in otherwise pain-free subjects using a modified version of the submaximal effort tourniquet technique. Subjects completed twelve cycles of the ischemic-induced pain test. The primary outcome measure was the change in self-reported of pain intensity during one of four possible treatments. [Results] There were significant effects for Time, which were attributed to a significant reduction in pain intensity for all groups. There were no significant effects for groups or group-time interaction. The 50 Hz IFC treatment was more comfortable than the other treatments in the present study, and it is likely to be better accepted and tolerated by patients. [Conclusion] We conclude that there were no differences in the analgesic effects of the four treatments under the present experimental conditions. The 50 Hz IFC treatment is more comfortable than the other treatments.

  5. The relationship of adult attachment to emotion, catastrophizing, control, threshold and tolerance, in experimentally-induced pain.

    PubMed

    Meredith, Pamela J; Strong, Jenny; Feeney, Judith A

    2006-01-01

    Although insecure attachment has been associated with a range of variables linked with problematic adjustment to chronic pain, the causal direction of these relationships remains unclear. Adult attachment style is, theoretically, developmentally antecedent to cognitions, emotions and behaviours (and might therefore be expected to contribute to maladjustment). It can also be argued, however, that the experience of chronic pain increases attachment insecurity. This project examined this issue by determining associations between adult attachment characteristics, collected prior to an acute (coldpressor) pain experience, and a range of emotional, cognitive, pain tolerance, intensity and threshold variables collected during and after the coldpressor task. A convenience sample of 58 participants with no history of chronic pain was recruited. Results demonstrated that attachment anxiety was associated with lower pain thresholds; more stress, depression, and catastrophizing; diminished perceptions of control over pain; and diminished ability to decrease pain. Conversely, secure attachment was linked with lower levels of depression and catastrophizing, and more control over pain. Of particular interest were findings that attachment style moderated the effects of pain intensity on the tendency to catastrophize, such that insecurely attached individuals were more likely to catastrophize when reporting high pain intensity. This is the first study to link attachment with perceptions of pain in a pain-free sample. These findings cast anxious attachment as a vulnerability factor for chronic pain following acute episodes of pain, while secure attachment may provide more resilience.

  6. UBC researcher's back-pain studies focus on space travel.

    PubMed

    Robinson, M

    1996-01-01

    Researchers at the University of British Columbia have been studying back pain that develops in astronauts in space. Their findings not only may help astronauts cope with future space travel, but also lead to new treatments for Earth-bound patients who experience back pain.

  7. A Validity Study of the Pain Apperception Test

    ERIC Educational Resources Information Center

    Haase, Richard F.; And Others

    1975-01-01

    This study assessed the validity of the Pain Apperception Test (PAT) against an accepted and validated predictive measure of pain tolerance, a Kinesthetic After Effects Task (KAE). As well, it replicated an earlier finding by Petrovich that suggested that scores derived from the PAT are related significantly to neuroticism. (Author/RK)

  8. Pain and anxiety control: an online study guide.

    PubMed

    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.

  9. Laughter, Humor and Pain Perception in Children: A Pilot Study

    PubMed Central

    Hilber, Sherry Dunay; Mintzer, Lisa Libman; Castaneda, Marleen; Glover, Dorie; Zeltzer, Lonnie

    2009-01-01

    Although there are many clinical programs designed to bring humor into pediatric hospitals, there has been very little research with children or adolescents concerning the specific utility of humor for children undergoing stressful or painful procedures. Rx Laughter™, a non-profit organization interested in the use of humor for healing, collaborated with UCLA to collect preliminary data on a sample of 18 children aged 7–16 years. Participants watched humorous video-tapes before, during and after a standardized pain task that involved placing a hand in cold water. Pain appraisal (ratings of pain severity) and pain tolerance (submersion time) were recorded and examined in relation to humor indicators (number of laughs/smiles during each video and child ratings of how funny the video was). Whereas humor indicators were not significantly associated with pain appraisal or tolerance, the group demonstrated significantly greater pain tolerance while viewing funny videos than when viewing the videos immediately before or after the cold-water task. The results suggest that humorous distraction is useful to help children and adolescents tolerate painful procedures. Further study is indicated to explore the specific mechanism of this benefit. PMID:18955244

  10. [Neuropathic pain and neuroplasticity in functional imaging studies].

    PubMed

    Maihöfner, C; Nickel, F T; Seifert, F

    2010-04-01

    Neuropathic pain syndromes are characterised by the occurrence of spontaneous ongoing and stimulus-induced pain. Stimulus-induced pain (hyperalgesia and allodynia) may result from sensitisation processes in the peripheral (primary hyperalgesia) or central (secondary hyperalgesia) nervous system. The underlying pathophysiological mechanisms at the nociceptor itself and at spinal synapses have become better understood. However, the cerebral processing of hyperalgesia and allodynia is still controversially discussed. In recent years, neuroimaging methods (functional magnetic resonance imaging, fMRI; magnetoencephalography, MEG; positron emission tomography, PET) have provided new insights into the aberrant cerebral processing of neuropathic pain. The present paper reviews different cerebral mechanisms contributing to chronicity processes in neuropathic pain syndromes. These mechanisms include reorganisation of cortical somatotopic maps in sensory or motor areas (highly relevant for phantom limb pain and CRPS), increased activity in primary nociceptive areas, recruitment of new cortical areas usually not activated by nociceptive stimuli and aberrant activity in brain areas normally involved in descending inhibitory pain networks. Moreover, there is evidence from PET studies for changes of excitatory and inhibitory transmitter systems. Finally, advanced methods of structural brain imaging (voxel-based morphometry, VBM) show significant structural changes suggesting that chronic pain syndromes may be associated with neurodegeneration.

  11. Effects of COX inhibition on experimental pain and hyperalgesia during and after remifentanil infusion in humans.

    PubMed

    Lenz, Harald; Raeder, Johan; Draegni, Tomas; Heyerdahl, Fridtjof; Schmelz, Martin; Stubhaug, Audun

    2011-06-01

    Opioids may enhance pain sensitivity resulting in opioid-induced hyperalgesia (OIH). Activation of spinal cyclooxygenase may play a role in the development of OIH. The aim of this study was to demonstrate remifentanil-induced postinfusion hyperalgesia in an electrical pain and a cold pain model, and to investigate whether COX-2 (parecoxib) or COX-1 (ketorolac) inhibition could prevent hyperalgesia after remifentanil infusion. Sixteen healthy males were enrolled in this randomized, double-blind, placebo-controlled crossover study. Each subject went through 4 sessions: control, remifentanil, parecoxib+remifentanil, and ketorolac+remifentanil. Transcutaneous electrical stimulation induced acute pain and areas of pinprick hyperalgesia. The areas of pinprick hyperalgesia were assessed before, during, and after a 30-minute infusion of either remifentanil or saline. The cold-pressor test (CPT) was performed before, at the end of, and 1 hour after the infusions. The subjects received a bolus of either saline, 40 mg parecoxib, or 30 mg ketorolac intravenously after the first CPT. The areas of pinprick hyperalgesia and CPT pain after the end of remifentanil infusion increased significantly compared to control (P < 0.001 and P = 0.005, respectively). Pretreatment with parecoxib or ketorolac reduced the postinfusion area of pinprick hyperalgesia (P < 0.001 and P = 0.001, respectively), compared to the remifentanil group. Parecoxib reduced the area significantly more than ketorolac (P = 0.009). In the CPT, pretreatment with parecoxib or ketorolac did not prevent postinfusion hyperalgesia. These results demonstrated OIH in both models, and may suggest that COX-2 inhibition is more important than COX-1 inhibition in reducing hyperalgesia. Remifentanil-induced hyperalgesia was demonstrated for both electrically induced pain and cold-pressor pain. Both parecoxib and ketorolac prevented hyperalgesia in the electrical model, parecoxib to a larger extent.

  12. Manipulating the Placebo Response in Experimental Pain by Altering Doctor’s Performance Style

    PubMed Central

    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

  13. Correlative study of 3 pain rating scales among obstetric patients.

    PubMed

    Akinpelu, A O; Olowe, O O

    2002-06-01

    The relationship between pain scores obtained on the Visual Analog Scale (VAS) the Box Numerical Scale (BNS) and Verbal Rating Scale (VRS) was studied. The subjects were 35 volunteer female patients who had their babies through caesarian section 1-3 days prior to the study. Demographic data and pain scores were collected through a questionnaire, which was available in both English and Yoruba, the two most commonly spoken languages in Ibadan where the study was carried out. Data were analysed using Pearson Product, Moment Correlation Coefficient, and One-way Analysis of Variance. Results indicated that there was no significant difference between the pain scores obtained on the 3 pain rating scales. Significant correlations existed between pain scores obtained on the VAS and VRS (r = 0.48, p = 0.003); VAS and BNS (r = 0.74, P = 0.000); BNS and VRS (r = 0.74, P = 0.000). High educational attainment improved correlation between the scales in this study. It was concluded that the three pain rating scales measure the same construct, and could be used for pain measurement in obstetrically related conditions in this environment.

  14. Pain neurophysiology education improves cognitions, pain thresholds, and movement performance in people with chronic whiplash: a pilot study.

    PubMed

    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.

  15. A Clinical Experimental Model to Evaluate Analgesic Effect of Remote Ischemic Preconditioning in Acute Postoperative Pain

    PubMed Central

    Pereira, Francisco Elano Carvalho; Mello, Irene Lopes; Pimenta, Fernando Heladio de Oliveira Medeiros; Costa, Debora Maia; Wong, Deysi Viviana Tenazoa; Fernandes, Claudia Regina; Lima Junior, Roberto César; Gomes, Josenília M. Alves

    2016-01-01

    This study aims to evaluate the viability of a clinical model of remote ischemic preconditioning (RIPC) and its analgesic effects. It is a prospective study with twenty (20) patients randomly divided into two groups: control group and RIPC group. The opioid analgesics consumption in the postoperative period, the presence of secondary mechanical hyperalgesia, the scores of postoperative pain by visual analog scale, and the plasma levels interleukins (IL-6) were evaluated. The tourniquet applying after spinal anesthetic block was safe, producing no pain for all patients in the tourniquet group. The total dose of morphine consumption in 24 hours was significantly lower in RIPC group than in the control group (p = 0.0156). The intensity analysis of rest pain, pain during coughing and pain in deep breathing, showed that visual analogue scale (VAS) scores were significantly lower in RIPC group compared to the control group: p = 0.0087, 0.0119, and 0.0015, respectively. There were no differences between groups in the analysis of presence or absence of mechanical hyperalgesia (p = 0.0704) and in the serum levels of IL-6 dosage over time (p < 0.0001). This clinical model of remote ischemic preconditioning promoted satisfactory analgesia in patients undergoing conventional cholecystectomy, without changing serum levels of IL-6. PMID:27446611

  16. A Clinical Experimental Model to Evaluate Analgesic Effect of Remote Ischemic Preconditioning in Acute Postoperative Pain.

    PubMed

    Pereira, Francisco Elano Carvalho; Mello, Irene Lopes; Pimenta, Fernando Heladio de Oliveira Medeiros; Costa, Debora Maia; Wong, Deysi Viviana Tenazoa; Fernandes, Claudia Regina; Lima Junior, Roberto César; Gomes, Josenília M Alves

    2016-01-01

    This study aims to evaluate the viability of a clinical model of remote ischemic preconditioning (RIPC) and its analgesic effects. It is a prospective study with twenty (20) patients randomly divided into two groups: control group and RIPC group. The opioid analgesics consumption in the postoperative period, the presence of secondary mechanical hyperalgesia, the scores of postoperative pain by visual analog scale, and the plasma levels interleukins (IL-6) were evaluated. The tourniquet applying after spinal anesthetic block was safe, producing no pain for all patients in the tourniquet group. The total dose of morphine consumption in 24 hours was significantly lower in RIPC group than in the control group (p = 0.0156). The intensity analysis of rest pain, pain during coughing and pain in deep breathing, showed that visual analogue scale (VAS) scores were significantly lower in RIPC group compared to the control group: p = 0.0087, 0.0119, and 0.0015, respectively. There were no differences between groups in the analysis of presence or absence of mechanical hyperalgesia (p = 0.0704) and in the serum levels of IL-6 dosage over time (p < 0.0001). This clinical model of remote ischemic preconditioning promoted satisfactory analgesia in patients undergoing conventional cholecystectomy, without changing serum levels of IL-6. PMID:27446611

  17. Space Adaptation Back Pain: A Retrospective Study

    NASA Technical Reports Server (NTRS)

    Kerstman, Eric

    2009-01-01

    Astronaut back pain is frequently reported in the early phase of space flight as they adapt to microgravity. The epidemiology of space adaptation back pain (SABP) has not been well established. This presentation seeks to determine the exact incidence of SABP among astronauts, develop a case definition of SABP, delineate the nature and pattern of SABP, review available treatments and their effectiveness in relieving SABP; and identify any operational impact of SABP. A retrospective review of all available mission medical records of astronauts in the U.S. space program was performed. It was revealed that the incidence of SABP has been determined to be 53% among astronauts in the U.S. space program; most cases of SABP are mild, self-limited, or respond to available treatment; there are no currently accepted preventive measures for SABP; it is difficult to predict who will develop SABP; the precise mechanism and spinal structures responsible for SABP are uncertain; there was no documented evidence of direction operational mission impact related to SABP; and, that there was the potential for mission impact related to uncontrolled pain, sleep disturbance, or the adverse side effects pf anti-inflammatory medications

  18. How pain empathy depends on ingroup/outgroup decisions: A functional magnet resonance imaging study.

    PubMed

    Ruckmann, Judith; Bodden, Maren; Jansen, Andreas; Kircher, Tilo; Dodel, Richard; Rief, Winfried

    2015-10-30

    Showing empathy is crucial for social functioning and empathy is related to group membership. The aim of the current study was to investigate the influence of experimentally generated groups on empathy for pain in a functional magnetic resonance imaging (fMRI) paradigm. Thirty healthy participants underwent a minimal group paradigm to create two groups. While BOLD contrast was measured using fMRI, subjects were instructed to empathize with ingroup and outgroup members, who were depicted in a picture paradigm of painful and neutral situations. Behavioral measure of state empathy was measured using a visual analog scale. Furthermore, self-reported trait empathy measures were obtained. Repeated-measures ANOVAs were conducted for fMRI and behavioral data. In addition to a main effect of pain in pain-related areas, a main effect of group in areas belonging to the visual cortex was found. Although there was no ingroup bias for empathy ratings, subjects showed altered neural activation in regions of the right fusiform gyrus, the cerebellum, the hippocampal and amygdala region during the pain×group interaction. Activation in the preceding structures, revealed by the interaction of pain by group, suggests that activation in the pallidum might reflect specific empathy for pain-related regulation processes. PMID:26323252

  19. How pain empathy depends on ingroup/outgroup decisions: A functional magnet resonance imaging study.

    PubMed

    Ruckmann, Judith; Bodden, Maren; Jansen, Andreas; Kircher, Tilo; Dodel, Richard; Rief, Winfried

    2015-10-30

    Showing empathy is crucial for social functioning and empathy is related to group membership. The aim of the current study was to investigate the influence of experimentally generated groups on empathy for pain in a functional magnetic resonance imaging (fMRI) paradigm. Thirty healthy participants underwent a minimal group paradigm to create two groups. While BOLD contrast was measured using fMRI, subjects were instructed to empathize with ingroup and outgroup members, who were depicted in a picture paradigm of painful and neutral situations. Behavioral measure of state empathy was measured using a visual analog scale. Furthermore, self-reported trait empathy measures were obtained. Repeated-measures ANOVAs were conducted for fMRI and behavioral data. In addition to a main effect of pain in pain-related areas, a main effect of group in areas belonging to the visual cortex was found. Although there was no ingroup bias for empathy ratings, subjects showed altered neural activation in regions of the right fusiform gyrus, the cerebellum, the hippocampal and amygdala region during the pain×group interaction. Activation in the preceding structures, revealed by the interaction of pain by group, suggests that activation in the pallidum might reflect specific empathy for pain-related regulation processes.

  20. 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

  1. Is HIV Painful? An Epidemiologic Study of the Prevalence and Risk Factors for Pain in HIV-Infected Patients

    PubMed Central

    Lawson, Edwina; Sabin, Caroline; Perry, Nicky; Richardson, Daniel; Gilleece, Yvonne; Churchill, Duncan; Dean, Gill; Williams, Debbie; Fisher, Martin; Walker-Bone, Karen

    2016-01-01

    Objectives To evaluate the prevalence, impact and risk factors for pain among a cohort of HIV-infected adults treated with combination anti-retroviral therapy (cART) if indicated according to current guidelines. Methods This was a cross-sectional epidemiological observational study. All patients attending one HIV-outpatient centre in the UK in a 10-month period were eligible. Patients completed a validated questionnaire enquiring about demographics, HIV factors and symptoms of pain. Results Of 1050 eligible participants, 859 (82%) completed a questionnaire. The 1-month period prevalence of pain lasting > 1 day was 62.8% amongst whom 63% reported current pain. The prevalence of pain at most anatomical sites was broadly similar to that observed in population studies using the same questionnaires except that we found considerably higher rates of foot/ankle pain. The median duration of pain was 3 years (range 0-51 years) and the median pain score was 5.0 on an 11-point visual analogue score. Over 40% of people in pain had consulted their primary care physician and > 20% were taking analgesics daily. Independent risk factors for current pain were older age (p=0.001), time since diagnosis of HIV infection (p=0.001) and receipt of a protease inhibitor-based regimen (p=0.04). Discussion Pain, and notably foot/ankle pain, is common among adults living with prevalent HIV and is associated with substantial morbidity and healthcare utilisation. PMID:25329144

  2. Pilot Study of Exercise Therapy on Painful Diabetic Peripheral Neuropathy

    PubMed Central

    Yoo, Min; D’Silva, Linda; Martin, Katherine; Sharma, Neena; Pasnoor, Mamatha; LeMaster, Joseph

    2015-01-01

    Objective Painful diabetic peripheral neuropathy (DPN) is a common complication of diabetes. While the beneficial effect of exercise on diabetes is well established, its effect specifically on painful DPN has not been thoroughly explored. The objective of this pilot study was to examine the effect of aerobic exercise on pain in people with DPN. Methods Fourteen sedentary individuals (mean age 57±5.11 years) with painful DPN were enrolled in a 16-week, supervised aerobic exercise program. The Brief Pain Inventory-Diabetic Peripheral Neuropathy (BPI-DPN) was used to assess pain intensity (worst, least, average, now) and pain interference with daily life (activity, mood, walk, normal work, relationship, sleep, enjoyment of life) pre- and post -intervention. Body mass index (BMI), maximum oxygen uptake (VO2max), hemoglobin A1c (HbA1c), and blood pressure were also measured pre-and post-intervention as secondary outcomes of interest. Results Significant reductions in pain interference were observed with walking (4.93±3.03 pre to 3.29±2.89 post, p=0.016), normal work (5.39±3.32 pre to 3.79±3.04 post, p=0.032), relationship with others (3.96±3.53 pre to 1.29±1.27 post, p=0.006), sleep (5.11±3.04 pre to 3.5±3.03 post, p=0.02), and the overall pain interference (4.65±2.70 pre to 2.97±2.22 post, p=0.013) following the intervention; however, there was no change in pain intensity. VO2max increased significantly post-intervention (16.02±3.84ml/kg/min pre to 17.18±4.19ml/kg/min, p=0.028), while BMI, HbA1c, and blood pressure remained unchanged. Conclusion These preliminary results suggest that perceived pain interference may be reduced following an aerobic exercise intervention among people with painful DPN, without a change in pain intensity. Further validation by a RCT is needed. PMID:25800666

  3. The effects of prior pain experience on neural correlates of empathy for pain: An fMRI study.

    PubMed

    Preis, Mira A; Schmidt-Samoa, Carsten; Dechent, Peter; Kroener-Herwig, Birgit

    2013-03-01

    Neuroimaging studies have revealed partially shared neural substrates for both the actual experience of pain and empathy elicited by the pain of others. We examined whether prior pain exposure increased neural activity in the anterior midcingulate cortex (aMCC) and bilateral anterior insula (AI) as a correlate of empathy for pain. Participants (N=64: 32 women, 32 men) viewed pictures displaying exposure to pressure pain (pain pictures) and pictures without any cue of pain (neutral pictures). Prior to the experiment, half of the participants were exposed to the same pain stimulus as the one seen in the pain pictures (pain exposure condition); the other half had no such experience (touch exposure condition). A balanced sex ratio was kept, to investigate possible sex differences. In the region-of-interest analyses, participants of the pain exposure condition showed decreased activity in the right AI and the aMCC relative to participants of the touch exposure condition. While in men, no differences were found in relation to their exposure condition, women with pain exposure showed decreased activity in the aMCC and additionally, in bilateral AI. Based on the entire sample, whole brain analyses revealed stronger activation in the retrosplenial cortex, dorsomedial prefrontal cortex, and medial prefrontal cortex in the pain exposure condition. In conclusion, prior pain exposure did not increase, but decreased activity in regions regularly associated with empathy for pain. However, pain experience increased activity in regions associated with memory retrieval, perspective taking, and top-down emotion regulation, which might facilitate empathizing with others.

  4. Inter-individual responses to experimental muscle pain: Baseline anxiety ratings and attitudes to pain do not determine the direction of the sympathetic response to tonic muscle pain in humans.

    PubMed

    Kobuch, Sophie; Fazalbhoy, Azharuddin; Brown, Rachael; Macefield, Vaughan G

    2016-06-01

    We have recently shown that intramuscular infusion of hypertonic saline, causing pain lasting ~60min, increases muscle sympathetic nerve activity (MSNA) in one group of subjects, yet decreases it in another. Across subjects these divergent sympathetic responses to long-lasting muscle pain are consistent over time and cannot be foreseen on the basis of baseline MSNA, blood pressure, heart rate or sex. We predicted that differences in anxiety or attitudes to pain may account for these differences. Psychometric measures were assessed prior to the induction of pain using the State and Trait Anxiety Inventory (STAI), Pain Vigilance and Awareness Questionnaire (PVAQ), Pain Anxiety Symptoms Scale (PASS) and Pain Catastrophising Scale (PCS); PCS was also administered after the experiment. MSNA was recorded from the common peroneal nerve, before and during a 45-minute intramuscular infusion of hypertonic saline solution into the tibialis anterior muscle of 66 awake human subjects. Forty-one subjects showed an increase in mean burst amplitude of MSNA (172.8±10.6%) while 25 showed a decrease (69.9±3.8%). None of the measured psychological parameters showed significant differences between the increasing and the decreasing groups. We conclude that inter-individual anxiety or pain attitudes do not determine whether MSNA increases or decreases during long-lasting experimental muscle pain in healthy human subjects. PMID:27106401

  5. Painful Bladder Filling and Painful Urgency Are Distinct Characteristics in Men and Women with Urologic Chronic Pelvic Pain Syndromes – A MAPP Research Network Study

    PubMed Central

    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

  6. Biochemical and pharmacological assessment of MAP-kinase signaling along pain pathways in experimental rodent models: a potential tool for the discovery of novel antinociceptive therapeutics.

    PubMed

    Edelmayer, Rebecca M; Brederson, Jill-Desiree; Jarvis, Michael F; Bitner, Robert S

    2014-02-01

    Injury to the peripheral or central nervous system can induce changes within the nervous tissues that promote a state of sensitization that may underlie conditions of pathological chronic pain. A key biochemical event in the initiation and maintenance of peripheral and central neuronal sensitization associated with chronic pain is the phosphorylation and subsequent activation of mitogen-activated protein kinases (MAPKs) and immediate early gene transcription factors, in particular cAMP-response element binding protein (CREB). In this commentary we review the preclinical data that describe anatomical and mechanistic aspects of nociceptive-induced signaling along nociceptive pathways including peripheral cutaneous axons, the dorsal root ganglia, spinal cord dorsal horn and cerebral cortex. In addition to the regional manifestation of nociceptive signaling, investigations have attempted to elucidate the cellular origin of biochemical nociceptive processing in which communication, i.e. cross-talk between neurons and glia is viewed as an essential component of pathogenic pain development. Here, we outline a research strategy by which nociceptive-induced cellular signaling in experimental pain models, specifically MAPK and CREB phosphorylation can be utilized to provide mechanistic insight into drug-target interaction along the nociceptive pathways. We describe a series of studies using nociceptive inflammatory and neuropathic pain models to investigate the effects of known pain therapeutics on nociceptive-induced biochemical signaling and present this as a complementary research strategy for assessing antinociceptive activity useful in the preclinical development of novel pain therapeutics.

  7. A single-blind placebo-controlled investigation into the analgesic effects of interferential currents on experimentally induced ischaemic pain in healthy subjects.

    PubMed

    Johnson, Mark I; Tabasam, Ghazala

    2002-05-01

    The aim of this single-blind placebo-controlled study was to examine the analgesic effects of interferential currents (IFC) on experimentally induced ischaemic pain. Ischaemic pain was induced using the submaximal effort tourniquet technique (SETT) and pain intensity was recorded using a visual analogue scale at 1-min intervals was used as the primary outcome measure. Following baseline recordings 30 healthy volunteers received either active IFC, sham IFC, or no treatment (10 subjects per group). Data were analysed by calculating the mean change in pain intensity at each 1-min interval by subtracting data during treatment from the baseline data. IFC was administered throughout the duration of the ischaemic pain test via four electrodes (quadripolar application) on the forearm. Active IFC delivered electrical currents at a 'strong but comfortable' intensity. A 'dummy' stimulator that delivered no current was used as sham IFC. Subjects in the no treatment control group were informed that the IFC device was not switched on. There were significant effects for Groups (P=0.04) which were attributed to a significant reduction in pain intensity for the IFC group when compared with sham and no-treatment control (P< or =0.05). There were no significant effects for Time (P=0.69) or Group-Time interaction (P=0.45). In conclusion, IFC produced significantly greater analgesia than sham and no-treatment control groups under the present experimental conditions.

  8. The re-evaluation of the measurement of pain in population-based epidemiological studies: The SHAMA study

    PubMed Central

    Flüß, Elisa; Bond, Christine M; Jones, Gareth T

    2015-01-01

    Background: While many pain patients rely on pain-relieving treatments to manage their pain, pain-related research commonly quantifies pain status using validated questionnaires without taking into account that information. This will lead to an underestimate of the burden of pain in the community. To ensure a more accurate assessment of the prevalence and severity of pain, this study aimed to develop a pain management questionnaire and to assess how much population-based pain estimates change when pain management is considered. Methods: This study was a cross-sectional population-based study in Grampian, north-east Scotland. A total of 4600 people, aged 25 years and over, were randomly selected from a population sample frame and sent a questionnaire on pain and pain management. Population estimates of pain were determined twice: with the use of standard pain status questionnaires (‘current pain’) and with the use of a newly developed enhanced pain status questionnaire to determine patients’ estimated pain without pain management (‘all pain’). Results: The prevalence of current pain was 50.5% (95% CI = 48.0, 52.9). Of those who reported no current pain, 11.6% (95% CI = 9.4, 13.8) reported that they would have had pain had they not managed their pain. Thus, the all pain prevalence was 56.2% (95% CI = 53.7, 58.7). This difference in prevalence rates was statistically significant (difference = 5.7%; 95% CI = 2.2, 9.2). Likewise, participants’ pain severity significantly increased when they estimated their pain without pain management (p < 0.001, Wilcoxon-signed rank test). Conclusions: Failure to assess pain management information results in an underestimation of pain prevalence and severity. This should be considered in future epidemiological studies. Summary points Pain management information is currently not considered for the assessment of pain in epidemiological population-based studies. Since pain management can affect

  9. Sleep deprivation, pain and prematurity: a review study.

    PubMed

    Bonan, Kelly Cristina Santos de Carvalho; Pimentel Filho, João da Costa; Tristão, Rosana Maria; Jesus, José Alfredo Lacerda de; Campos Junior, Dioclécio

    2015-02-01

    The aim was to describe current reports in the scientific literature on sleep in the intensive care environment and sleep deprivation associated with painful experiences in premature infant. A systematic search was conducted for studies on sleep, pain, premature birth and care of the newborn. Web of Knowledge, MEDLINE, LILACS, Cochrane Library, PubMed, EMBASE, Scopus, VHL and SciELO databases were consulted. The association between sleep deprivation and pain generates effects that are observed in the brain and the behavioral and physiological activity of preterm infants. Polysomnography in intensive care units and pain management in neonates allow comparison with the first year of life and term infants. We have found few references and evidence that neonatal care programs can influence sleep development and reduce the negative impact of the environment. This evidence is discussed from the perspective of how hospital intervention can improve the development of premature infants.

  10. Partners with Bad Temper: Reject or Cure? A Study of Chronic Pain and Aggression in Horses

    PubMed Central

    Fureix, Carole; Menguy, Hervé; Hausberger, Martine

    2010-01-01

    Background Experiencing acute pain can affect the social behaviour of both humans and animals and can increase the risk that they exhibit aggressive or violent behaviour. However, studies have focused mainly on the impact of acute rather than chronic painful experiences. As recent results suggest that chronic pain or chronic discomfort could increase aggressiveness in humans and other mammals, we tested here the hypothesis that, in horses, aggression towards humans (a common source of accidents for professionals) could be linked to regularly reported vertebral problems of riding horses. Methodology/Principal Findings Vertebral examination and standardized behavioural tests were made independently on the same horses. Here we showed that most horses severely affected by vertebral problems were prone to react aggressively towards humans (33/43 horses, chi-square test, df = 1, χ2 = 12.30, p<0.001), which was not the case for unaffected or slightly affected horses (9/16 horses, chi-square test, df = 1, χ2 = 0.25, p>0.05). The more affected they were, the fewer positive reactions they exhibited (rs = −0.31, p = 0.02). Conclusions/Significance This is to our knowledge the first experimental evidence of such a link between chronic discomfort/potential pain (inferred from the presence of vertebral problems) and aggression, suggesting that chronic painful experiences may act in ways similar to those of acute experiences. Chronic discomfort or pain may often be overlooked when facing “bad tempered” individuals, whether humans or animals. This experimental study confirms the importance of including chronic discomfort or pain as a major factor in interpersonal relations and models of aggression. PMID:20865160

  11. Interdisciplinary hospice team processes and multidimensional pain: a qualitative study.

    PubMed

    Dugan Day, Michele

    2012-01-01

    Hospice teams may address multidimensional pain through the synergistic interaction of team members from various professional disciplines during regularly scheduled team meetings. However, the occurrence of that critical exchange has not been adequately described or documented. The purpose of this qualitative study was to explore two processes in team pain palliation: communication and collaboration. Data were gathered through individual interviews and a 1-year observation of team members from two hospices (physicians, nurses, aides, chaplains, social workers). Utilizing constant comparison, 14 final thematic categories were discovered. Use of biopsychosocial/spiritual terms by all team members meant that the team had the common language needed to communicate about multidimensional pain. Interviews and observation revealed a gap in translating multidisciplinary communication in team meetings into collaborative acts for pain treatment. In addition, structural influences inhibited creativity in pain palliation. There was no mutual understanding of the purpose for team meetings, no recognition of the need to reflect on team process, or common definition of leadership. Social work roles in hospice should include leadership that moves teams toward interdisciplinary care for multidimensional pain.

  12. [Experimental studies of micromotor headpieces].

    PubMed

    Kanaev, V F; Repin, V A

    1982-01-01

    Experimental studies of handpieces for micromotors have been performed to make more precise their operating parameters. The special stand has been used for the measurements of the following data: head temperature, power losses in handpieces at no-load, and operating power required for machining by means of spherical burrs. The experimental results made it possible to specify more exactly the range of handpiece rotational speeds and to select optimum loads under reliability testing. PMID:7050601

  13. Experimental Pain and Opioid Analgesia in Volunteers at High Risk for Obstructive Sleep Apnea

    PubMed Central

    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

  14. Painful Temporomandibular Disorder: Decade of Discovery from OPPERA Studies.

    PubMed

    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

  15. Effects of cause of pain on the processing of pain in others: an ERP study.

    PubMed

    Lyu, Zhenyong; Meng, Jing; Jackson, Todd

    2014-09-01

    Determining how the perceived cause of pain influences the perception of pain in others has implications for prosocial behavior and moral reasoning. In this research, behavior and event-related potential (ERP) responses were recorded as 28 participants (12 men, 16 women) viewed images of painful situations said to be self-inflicted by the protagonist or caused by another person on the protagonist. As predicted, participants provided significantly higher pain intensity ratings for depictions featuring pain caused by another person than depictions of self-inflicted pain. ERP analyses showed no significant differences between protagonist alone and protagonist with other images of pain in the early negative component (N1). However, contrary to initial hypotheses, more positive P3 amplitudes were induced by images of self-inflicted pain in protagonists than images of protagonist pain caused by another person. Salience was considered as a key influence that may help to account for this pattern of findings.

  16. Balneotherapy for chronic low back pain: a randomized, controlled study.

    PubMed

    Kesiktas, Nur; Karakas, Sinem; Gun, Kerem; Gun, Nuran; Murat, Sadiye; Uludag, Murat

    2012-10-01

    A large number of treatments were used for patients with chronic low back pain. Frequent episodes have been reported very high. Although balneotherapy was found effective in this disease, there are not well-designed studies. We aimed to determine the effectiveness of balneotherapy versus physical therapy in patients with chronic low back pain. Exercise was added to both treatment programs. Sixty patients with chronic low back pain were randomly divided into two groups. Physical modalities plus exercise were applied to group 1, and group 2 was received balneotherapy plus exercise for ten sessions. The following parameters were measured: visual analogue scale at rest and movement for pain, paracetamol dose, manual muscle test for lumber muscles, modified Schoeber' test, Oswestry disability index, and Short-Form 36 at the beginning and end of the therapies and at the 3 months follow-up. The statistical analyses were performed using the SPSS 10.0 program. Both groups achieved significant improvements within themselves. But balneotherapy groups were improved at back extensor muscle test (P < 0.05), modified Schoeber's test (P < 0.03), Oswestry disability index, and the some scores of SF 36 (energy vitality, social function, role limitations related to physical problems, and general health P < 0.05). Balneotherapy combined with exercise therapy had advantages than therapy with physical modalities plus exercise in improving quality of life and flexibility of patients with chronic low back pain.

  17. A longitudinal study of low back pain in student nurses.

    PubMed

    Klaber Moffett, J A; Hughes, G I; Griffiths, P

    1993-06-01

    Results from a longitudinal study of low back pain in 199 student nurses followed up for 20 months show that 37% reported back pain which lasted for at least 3 consecutive days. The first incidence peaked markedly between 9 and 12 months into training, and coincided with work on wards described by the nurses as "heavy". A combination of personal characteristics are also associated with back pain reports, within this group of nurses. These include attitudes to health as measured by the Health Locus of Control, low levels of trait anxiety, increased neuroticism, and emotional disturbance as measured by the General Health Questionnaire, the strength endurance of the thigh muscles (quadriceps), and height. Recommendations are made for: (1) the consideration of a modified training programme for lifting and handling; and (2) the need for a standardized system of recording back problems as suggested by the DHSS-commissioned Robens Institute (University of Surrey) Report.

  18. Five-factor personality traits and pain sensitivity: a twin study.

    PubMed

    Vassend, Olav; Røysamb, Espen; Nielsen, Christopher S

    2013-05-01

    Factors underlying individual differences in pain responding are incompletely understood, but are likely to include genetic influences on basal pain sensitivity in addition to demographic characteristics such as age, sex, and ethnicity, and psychological factors including personality. This study sought to explore the relationship between personality traits and experimental pain sensitivity, and to determine to what extent the covariances between these phenotypes are mediated by common genetic and environmental factors. A sample composed of 188 twins, aged 23 to 35years, was included in the study. Heat pain intensity (HPI) and cold-pressor pain intensity (CPI) ratings were obtained using standardized pain testing procedures, and personality traits were assessed with the NEO Personality Inventory, Revised. Associations between personality and the pain sensitivity indices were examined using zero-order correlations and generalized estimating equations. Bivariate Cholesky models were used in the biometric analyses. The most robust finding was a significant phenotypic association between CPI and the personality facets Impulsiveness (a facet of Neuroticism) and Excitement-Seeking (a facet of Extraversion), and estimates of the genetic correlation were .37 (P<.05) and .43 (P<.05), respectively. In contrast, associations between HPI and personality seemed weak and unstable, but a significant effect of Angry Hostility (a facet of Neuroticism) emerged in generalized estimating equations analysis. Although the genetic correlation between these phenotypes was essentially zero, a weak but significant individual-specific environmental correlation emerged (re=.21, P<.05). Taken together, these findings suggest that CPI is more consistently related to personality dispositions than HPI, both phenotypically and genetically.

  19. Forced-exercise delays neuropathic pain in experimental diabetes: effects on voltage-activated calcium channels.

    PubMed

    Shankarappa, Sahadev A; Piedras-Rentería, Erika S; Stubbs, Evan B

    2011-07-01

    Physical exercise produces a variety of psychophysical effects, including altered pain perception. Elevated levels of centrally produced endorphins or endocannabinoids are implicated as mediators of exercise-induced analgesia. The effect of exercise on the development and persistence of disease-associated acute/chronic pain remains unclear. In this study, we quantified the physiological consequence of forced-exercise on the development of diabetes-associated neuropathic pain. Euglycemic control or streptozotocin (STZ)-induced diabetic adult male rats were subdivided into sedentary or forced-exercised (2-10 weeks, treadmill) subgroups and assessed for changes in tactile responsiveness. Two weeks following STZ-treatment, sedentary rats developed a marked and sustained hypersensitivity to von Frey tactile stimulation. By comparison, STZ-treated diabetic rats undergoing forced-exercise exhibited a 4-week delay in the onset of tactile hypersensitivity that was independent of glucose control. Exercise-facilitated analgesia in diabetic rats was reversed, in a dose-dependent manner, by naloxone. Small-diameter (< 30 μm) DRG neurons harvested from STZ-treated tactile hypersensitive diabetic rats exhibited an enhanced (2.5-fold) rightward (depolarizing) shift in peak high-voltage activated (HVA) Ca(2+) current density with a concomitant appearance of a low-voltage activated (LVA) Ca(2+) current component. LVA Ca(2+) currents present in DRG neurons from hypersensitive diabetic rats exhibited a marked depolarizing shift in steady-state inactivation. Forced-exercise attenuated diabetes-associated changes in HVA Ca(2+) current density while preventing the depolarizing shift in steady-state inactivation of LVA Ca(2+) currents. Forced-exercise markedly delays the onset of diabetes-associated neuropathic pain, in part, by attenuating associated changes in HVA and LVA Ca(2+) channel function within small-diameter DRG neurons possibly by altering opioidergic tone. PMID:21554321

  20. Informal hospice caregiver pain management concerns: A qualitative study

    PubMed Central

    Kelley, Marjorie; Demiris, George; Nguyen, Huong; Oliver, Debra P; Wittenberg-Lyles, Elaine

    2014-01-01

    Background Informal, unpaid, family caregivers provide much hospice care in the United States. These caregivers suffer physically, psychologically, emotionally, and socially from the burden of caring. The most often identified area of caregiver burden is the management of end-of-life pain. However, little empirical evidence exists of effective interventions to help caregivers manage end-of-life pain, and issues surrounding caregiver pain management remain vague and undefined. Understanding these concerns will inform the design of effective caregiver interventions. Aim The purpose of this study was to describe and organize caregiver pain management challenges faced by home hospice caregivers of cancer patients. Design A content analysis of secondary data, namely, recordings of caregiver interviews, was conducted to describe pain management issues. These interviews were part of a larger clinical trial. Setting/participants Multiple sessions with 29 informal caregivers, of patients dying of cancer, were audio-recorded. Subjects were purposively selected from two hospice programs in the Northwestern United States. Caregivers of noncancer patients were excluded from the study sample. Results A framework of six major themes with subordinate subthemes was developed through a literature review and peer review. The framework was used to organize the content of 87 caregiver interviews. The six major themes identified in the analysis included Caregiver-Centric Issues, Caregiver Medication Skills and Knowledge Issues, End-of-Life Symptom Knowledge Issues, Communication and Teamwork Issues, Organizational Skill Issues, and Patient-Centric Issues. Conclusion This analysis clearly articulated and classified caregiver issues surrounding pain management. Future hospice research may benefit from the use of this analysis and framework in the development of tools to alleviate this major cause of caregiver burden. PMID:23612959

  1. Breakthrough pain in patients with controlled or uncontrolled pain: An observational study

    PubMed Central

    Gatti, Antonio; Gentili, Marta; Baciarello, Marco; Lazzari, Marzia; Marzi, Rossella; Palombo, Elisa; Sabato, Alessandro F; Fanelli, Guido

    2014-01-01

    BACKGROUND: Breakthrough pain (BTP) is traditionally defined as a pain exacerbation in patients with chronic controlled pain. However, this definition has recently been challenged. OBJECTIVES: To evaluate the prevalence of unsatisfactory control in patients with chronic cancer pain, and investigate the frequency and intensity of BTP episodes. METHODS: A total of 665 patients with chronic cancer pain attending 21 pain therapy units in Italy were evaluated for baseline pain intensity and number of BTP episodes over a 30-day period. All patients started, continued or modified treatment for BTP at enrollment, according to medical judgment. RESULTS: The number of BTP events was higher in patients with uncontrolled baseline pain, although the intensity and duration of episodes were similar. In patients with uncontrolled baseline pain, the number of events decreased with time and reached values comparable with those reported in patients with controlled pain. Both the intensity of the pain and the duration of the BTP events exhibited similar values in the two groups at all time points, following increased monitoring and the prescription of analgesic medication. CONCLUSION: Patients with uncontrolled baseline pain experienced BTP flares with higher frequency, but similar intensity and duration with respect to patients with controlled pain at baseline. Notably, a close follow-up and adequate management of the BTP episodes led to an improvement of BTP in the observed patients. PMID:24945289

  2. Pain Perceptions of the Oldest Old: A Longitudinal Study

    ERIC Educational Resources Information Center

    Zarit, Steven H.; Griffiths, Patricia C.; Berg, Stig

    2004-01-01

    Purpose: This study assessed self-reported pain in the oldest old and examined its changes over time and in relation to other measures of health and functioning. Design and Methods: A population-based sample of the oldest old (86-92 years of age) residing in Sweden who were participating in a multiwave longitudinal investigation were interviewed…

  3. Identification of clusters of individuals relevant to temporomandibular disorders and other chronic pain conditions: the OPPERA study.

    PubMed

    Bair, Eric; Gaynor, Sheila; Slade, Gary D; Ohrbach, Richard; Fillingim, Roger B; Greenspan, Joel D; Dubner, Ronald; Smith, Shad B; Diatchenko, Luda; Maixner, William

    2016-06-01

    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

  4. Posterior shoulder pain and anterior instability: a preliminary clinical study.

    PubMed

    Castagna, Alessandro; Conti, Marco; Borroni, Mario; Massazza, Giuseppe; Vinci, Enzo; Franceschi, Giorgio; Garofalo, Raffaele

    2008-02-01

    Different clinical tests have been suggested in the literature as significant indicators of anterior shoulder instability. Sometimes patients with recurrent anterior shoulder instability may show some muscular guarding thus making the evaluation of specific clinical tests very difficult. These patients may also report a medical history with posterior shoulder pain that can be also elicited during some clinical manoeuvres. From September 2005 to September 2006 we prospectively studied patients who underwent an arthroscopic anterior capsuloplasty. Shoulder clinical examination was performed including anterior shoulder instability tests (drawer, apprehension and relocation tests). Furthermore the exam was focused on the presence of scapular dyskinesia and posterior shoulder pain. The patients were also evaluated with ASES, Rowe, SST (Simple Shoulder Test), Constant and UCLA (University of California at Los Angeles) scoring system preoperatively and at the latest follow-up time. In the period of this study we observed 16 patients treated for anterior gleno-humeral arthroscopic stabilisation, who preoperatively complained also of a posterior scapular pain. The pain was referred at the level of lower trapezium and upper rhomboids tendon insertion on the medial border of the scapula. It was also reproducible upon local palpation by the examiner. Four of these patients also referred pain in the region of the insertion of the infraspinatus and teres minor. After arthroscopic stabilisation the shoulder was immobilised in a sling with the arm in the neutral rotation for a period of 4 weeks. A single physician supervised shoulder rehabilitation. After a mean time of 6.8 months of follow-up, all the shoulder scores were significantly improved and, moreover, at the same time the patients referred the disappearance of the posterior pain. Posterior scapular shoulder pain seems to be another complaint and sign that can be found in patients affected by anterior shoulder instability

  5. Dynamic pain phenotypes are associated with spinal cord stimulation-induced reduction in pain: A repeated measures observational pilot study

    PubMed Central

    Campbell, Claudia M.; Buenaver, Luis F.; Raja, Srinivasa N.; Kiley, Kasey B.; Swedberg, Lauren; Wacnik, Paul W.; Cohen, Steven P.; Erdek, Michael A.; Williams, Kayode A.; Christo, Paul J.

    2015-01-01

    Objective 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. Methods The current study evaluated clinical, psychological and laboratory pain measures at baseline, during trial SCS lead placement, as well as one month and three 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 three months post SCS implantation. Results Results suggest few changes in QST over time. However, central sensitization and CPM at baseline were significantly associated with clinical pain at three 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 three months following SCS implantation. Conclusions 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. PMID:25800088

  6. Pain Experience in Hemophilia Patients: A Hermeneutic Phenomenological Study

    PubMed Central

    Rambod, Masoume; Sharif, Farkhondeh; Molazem, Zahra; Khair, Kate

    2016-01-01

    ABSTRACT Background: Pain, as a crucial subsequence of joint hemorrhages in hemophilia patients, is chronic, debilitating, and distracting. This study aimed to describe and interpret pain experiences of hemophilia patients in their lives. Methods: This qualitative study with hermeneutic phenomenological approach was conducted on fourteen hemophilia patients who had been referred to a hemophilia center affiliated to Shiraz University of Medical Sciences, Shiraz, Iran. The study question was “what is the meaning of pain in hemophilia patients’ lives? The data were collected through semi-structured interviews and field notes through purposeful sampling. Then, thematic analysis with van Manen’s six-step methodological framework was used. MAX.QDA qualitative software package, 2010, was used to analyze the data. Results: The three main themes that emerged in this study were “alteration in physical health”, “engagement in psychological problems”, and “impairment in social relationships”. Alteration in physical health consisted of three subthemes, namely “impairment of physical function”, “change in body physics”, and “disturbance in sleep quality”. In addition, two subthemes including “nostalgia of pain in adults with hemophilia” and “psychological distress” emerged from engagement in psychological problems. Finally, “loss of social activity” and “change in relationships” were related to impairment in social relationships. Conclusion: The present study highlighted alteration in physical health, engagement in psychological problems, and impairment in social relationship as a result of pain in hemophilia patients. Thus, healthcare providers and family members have to pay special attention to these problems. Besides, providing complementary therapy interventions is suggested for reducing these issues. PMID:27713894

  7. Associations among temporomandibular disorders, chronic neck pain and neck pain disability in computer office workers: a pilot study.

    PubMed

    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. PMID:26732204

  8. Pain relief with lidocaine 5% patch in localized peripheral neuropathic pain in relation to pain phenotype: a randomised, double-blind, and placebo-controlled, phenotype panel study.

    PubMed

    Demant, Dyveke T; Lund, Karen; Finnerup, Nanna B; Vollert, Jan; Maier, Christoph; Segerdahl, Märtha S; Jensen, Troels S; Sindrup, Søren H

    2015-11-01

    In neuropathic pain with irritable nociceptor (IN) phenotype, upregulation of sodium channels on nociceptors is supposed to be an important pain mechanism that may be targeted by topical sodium channel blockade. This randomised, double-blind, phenotype panel, crossover study with 4-week treatment periods of lidocaine 5% patch and placebo was performed to search for phenotype differences in effect. The primary efficacy measure was the total pain intensity on an 11-point numeric rating scale, and the primary objective was to compare the effect of lidocaine in patients with and without IN phenotype as defined by hypersensitivity and preserved small-fibre function determined by quantitative sensory testing. Forty-six patients with neuropathic pain due to nerve injury or postherpetic neuralgia were randomised. The modified intention-to-treat population comprised 15 patients with irritable nociceptor and 25 patients with nonirritable nociceptor. In the total sample, lidocaine reduced pain by 0.3 numeric rating scale points (95% confidence interval [CI]: 0.1-0.5) and pain-related sleep disturbance by 0.6 points (95% CI: 0.4-0.8) more than placebo (P = 0.007 and P < 0.001) and relieved pain by 0.4 verbal score (-1-5) points more (P = 0.036). For these measures, there was no significant interaction between treatment and phenotype, but there was a significant interaction for pain paroxysms (0.8, 95% CI: 0.4-1.2, P < 0.001) and deep aching pain (0.6, 95% CI: 0.1-1.0, P = 0.013). In conclusion, lidocaine 5% patch had an effect on peripheral neuropathic pain, and it may be most efficacious in patients with IN phenotype. The lack of significant phenotype differences may be caused by too low statistical power.

  9. Generating physical symptoms from visual cues: An experimental study.

    PubMed

    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. PMID:20183542

  10. Does weather affect daily pain intensity levels in patients with acute low back pain? A prospective cohort study.

    PubMed

    Duong, Vicky; Maher, Chris G; Steffens, Daniel; Li, Qiang; Hancock, Mark J

    2016-05-01

    The aim of this study was to investigate the influence of various weather parameters on pain intensity levels in patients with acute low back pain (LBP). We performed a secondary analysis using data from the PACE trial that evaluated paracetamol (acetaminophen) in the treatment of acute LBP. Data on 1604 patients with LBP were included in the analysis. Weather parameters (precipitation, temperature, relative humidity, and air pressure) were obtained from the Australian Bureau of Meteorology. Pain intensity was assessed daily on a 0-10 numerical pain rating scale over a 2-week period. A generalised estimating equation analysis was used to examine the relationship between daily pain intensity levels and weather in three different time epochs (current day, previous day, and change between previous and current days). A second model was adjusted for important back pain prognostic factors. The analysis did not show any association between weather and pain intensity levels in patients with acute LBP in each of the time epochs. There was no change in strength of association after the model was adjusted for prognostic factors. Contrary to common belief, the results demonstrated that the weather parameters of precipitation, temperature, relative humidity, and air pressure did not influence the intensity of pain reported by patients during an episode of acute LBP.

  11. Caloric Vestibular Stimulation Reduces Pain and Somatoparaphrenia in a Severe Chronic Central Post-Stroke Pain Patient: A Case Study.

    PubMed

    Spitoni, Grazia Fernanda; Pireddu, Giorgio; Galati, Gaspare; Sulpizio, Valentina; Paolucci, Stefano; Pizzamiglio, Luigi

    2016-01-01

    Central post-stroke pain is a neuropathic syndrome characterized by intolerable contralesional pain and, in rare cases, somatic delusions. To date, there is limited evidence for the effective treatments of this disease. Here we used caloric vestibular stimulation to reduce pain and somatoparaphrenia in a 57-year-old woman suffering from central post-stroke pain. Resting-state functional magnetic resonance imaging was used to assess the neurological effects of this treatment. Following vestibular stimulation we observed impressive improvements in motor skills, pain, and somatic delusions. In the functional connectivity study before the vestibular stimulation, we observed differences in the patient's left thalamus functional connectivity, with respect to the thalamus connectivity of a control group (N = 20), in the bilateral cingulate cortex and left insula. After the caloric stimulation, the left thalamus functional connectivity with these regions, which are known to be involved in the cortical response to pain, disappeared as in the control group. The beneficial use of vestibular stimulation in the reduction of pain and somatic delusion in a CPSP patient is now documented by behavioral and imaging data. This evidence can be applied to theoretical models of pain and body delusions. PMID:27028404

  12. Caloric Vestibular Stimulation Reduces Pain and Somatoparaphrenia in a Severe Chronic Central Post-Stroke Pain Patient: A Case Study

    PubMed Central

    2016-01-01

    Central post-stroke pain is a neuropathic syndrome characterized by intolerable contralesional pain and, in rare cases, somatic delusions. To date, there is limited evidence for the effective treatments of this disease. Here we used caloric vestibular stimulation to reduce pain and somatoparaphrenia in a 57-year-old woman suffering from central post-stroke pain. Resting-state functional magnetic resonance imaging was used to assess the neurological effects of this treatment. Following vestibular stimulation we observed impressive improvements in motor skills, pain, and somatic delusions. In the functional connectivity study before the vestibular stimulation, we observed differences in the patient’s left thalamus functional connectivity, with respect to the thalamus connectivity of a control group (N = 20), in the bilateral cingulate cortex and left insula. After the caloric stimulation, the left thalamus functional connectivity with these regions, which are known to be involved in the cortical response to pain, disappeared as in the control group. The beneficial use of vestibular stimulation in the reduction of pain and somatic delusion in a CPSP patient is now documented by behavioral and imaging data. This evidence can be applied to theoretical models of pain and body delusions. PMID:27028404

  13. Does weather affect daily pain intensity levels in patients with acute low back pain? A prospective cohort study.

    PubMed

    Duong, Vicky; Maher, Chris G; Steffens, Daniel; Li, Qiang; Hancock, Mark J

    2016-05-01

    The aim of this study was to investigate the influence of various weather parameters on pain intensity levels in patients with acute low back pain (LBP). We performed a secondary analysis using data from the PACE trial that evaluated paracetamol (acetaminophen) in the treatment of acute LBP. Data on 1604 patients with LBP were included in the analysis. Weather parameters (precipitation, temperature, relative humidity, and air pressure) were obtained from the Australian Bureau of Meteorology. Pain intensity was assessed daily on a 0-10 numerical pain rating scale over a 2-week period. A generalised estimating equation analysis was used to examine the relationship between daily pain intensity levels and weather in three different time epochs (current day, previous day, and change between previous and current days). A second model was adjusted for important back pain prognostic factors. The analysis did not show any association between weather and pain intensity levels in patients with acute LBP in each of the time epochs. There was no change in strength of association after the model was adjusted for prognostic factors. Contrary to common belief, the results demonstrated that the weather parameters of precipitation, temperature, relative humidity, and air pressure did not influence the intensity of pain reported by patients during an episode of acute LBP. PMID:26759130

  14. Association between sensitisation and pain-related behaviours in an experimental canine model of osteoarthritis.

    PubMed

    Rialland, Pascale; Otis, Colombe; Moreau, Maxim; Pelletier, Jean-Pierre; Martel-Pelletier, Johanne; Beaudry, Francis; Del Castillo, Jerome R E; Bertaim, Thierry; Gauvin, Dominique; Troncy, Eric

    2014-10-01

    Evaluation of nociceptive sensitisation in canine osteoarthritis studies has been poorly reported, or even related to other clinical symptoms. In 16 dogs, peak vertical force (PVF), subjective pain assessment using 3 scales, sympathetic stress response with electrodermal activity (EDA) measurement, and behavioural changes with video analysis and telemetered motor activity were quantified at baseline (D-7), and 28 and 56 days post transection of the cranial cruciate ligament. As markers of central sensitisation, selected spinal cord biomarkers (substance P and transthyretin) were quantified at D56. Electrical withdrawal thresholds on the stifle and the tail were measured as indicative of peripheral and central quantitative sensory testing (QST) sensitisation, respectively. The effects of vehicle administration (n=8) were compared with tiludronate (2mg/kg subcutaneously, q2 week, starting at D0) administration. Generalized estimated equations tested the association between the behavioural and physiological methods and QST sensitisation, and therefore the sensitivity of the methods for detecting treatment efficacy. Compared to tiludronate, at D56, vehicle-treated dogs had increased spinal substance P (P=0.01), concomitant decreased transthyretin (P=0.02), and (compared to baseline) demonstrated peripheral and central QST sensitisation, which was not present for tiludronate. Only PVF, the spontaneous behaviour "walking with full weight-bearing," and EDA were associated with occurrence of QST sensitisation and indicated significant tiludronate analgesic efficacy after inclusion of central QST sensitisation as a predictor variable in the statistical model. This study establishes the strong interest to implement QST as a predictor of canine osteoarthritis pain symptoms explained by pain sensitisation.

  15. A comparison of the clinical and experimental characteristics of four acute surgical pain models: dental extraction, bunionectomy, joint replacement, and soft tissue surgery.

    PubMed

    Singla, Neil K; Desjardins, Paul J; Chang, Phoebe D

    2014-03-01

    When a clinical trial of an analgesic produces a negative finding, it is important to consider the influence (if any) of experimental error on the validity of that result. Although efforts to identify and minimize experimental error in chronic pain investigations have begun in earnest, less work has been performed on the optimization of acute pain methodology. Of the acute surgical pain methodology articles that have been published over the last decade, almost all focus on either the dental or bunion model. Analgesics are typically evaluated in a variety of surgical models that eventually include hospital-based models (eg, joint replacement and soft tissue surgery). Every surgical procedure has unique clinical characteristics that must be considered to optimize study design and conduct. Much of the methodological knowledge garnered from bunion and dental studies is applicable to other surgical models, but some extrapolations are hazardous. The purposes of this review were (1) to qualitatively describe the clinical and experimental characteristics of the 4 classic surgical models: dental extraction, bunionectomy, joint replacement, and soft tissue surgery; and (2) to quantitatively compare the models by analyzing 3 factors: effect size, enrollment rate, and demographics. We found that the dental extraction and bunionectomy models had higher assay sensitivity than the joint replacement and soft tissue surgery models. It is probable that this finding is secondary to the superior experimental conditions under which the dental and bunion models are executed (utilization of few centers that have the ability to reduce surgical, anesthetic, and postoperative confounders).

  16. [A study on the pattern of pain expression of peptic ulcer patients].

    PubMed

    Kim, J S; Choi, Y H

    1991-08-01

    Pain is a subjective and multidimensional concept. Therefore the patient's expression of pain have been referred to the best believable indicator of pain condition but the support data obtained from the patient considered cultural difference is a deficient condition in determined on the precise nursing diagnosis. The purpose of this research was to understand multiple pain responses in cultural difference and sensitivity, to encourage communication between medical teams, and to provide the foundation data of on data of precise nursing assessment for the patient in pain. The research problem was to grasp pain express pattern of Korean peptic ulcer patients. The subjects were 20 peptic ulcer patients in medical unit or OPD of twp university hospitals in Seoul. Data were collected from September 7th to 22nd, 1990 by intensive interviews. Interviews were done by the researcher and all were tape-recorded. The Data analysis was done by Phenomenological method from Van Kaam. Validity assured by confirmation of the internal consistency of the statements and category by nursing colleague in educational and clinicians in medical care. From the emic data, 96 descriptive statements were organized in 18 theme cluster. The results of study were summarized as follows. 1. Pain Express Pattern cluster of Peptic Ulcer Patients were "pain as clogging", "shallow pain", "pain as pressing", "nauseateing pain", "pain as smarting", "pain as pulling", "pain as pricking", "pain as bursting", "wrenching pain", "excising pain", "uncontrollable pain for mind and body", "awakening pain", "pain as hollowing" and the other cluster. As above mentioned, Pain Express Pattern of Peptic Ulcer Patient appeared diversely in verbal and they were propered to Korean culture. Therefore they will provide for the foundation data of precise nursing assessment.

  17. A Prospective Cohort Study Evaluating the Ability of Anticipated Pain, Perceived Analgesic Needs, and Psychological Traits to Predict Pain and Analgesic Usage following Cesarean Delivery.

    PubMed

    Carvalho, Brendan; Zheng, Ming; Harter, Scott; Sultan, Pervez

    2016-01-01

    Introduction. This study aimed to determine if preoperative psychological tests combined with simple pain prediction ratings could predict pain intensity and analgesic usage following cesarean delivery (CD). Methods. 50 healthy women undergoing scheduled CD with spinal anesthesia comprised the prospective study cohort. Preoperative predictors included 4 validated psychological questionnaires (Anxiety Sensitivity Index (ASI), Fear of Pain (FPQ), Pain Catastrophizing Scale, and Eysenck Personality Questionnaire) and 3 simple ratings: expected postoperative pain (0-10), anticipated analgesic threshold (0-10), and perceived analgesic needs (0-10). Postoperative outcome measures included post-CD pain (combined rest and movement) and opioid used for the 48-hour study period. Results. Bivariate correlations were significant with expected pain and opioid usage (r = 0.349), anticipated analgesic threshold and post-CD pain (r = -0.349), and perceived analgesic needs and post-CD pain (r = 0.313). Multiple linear regression analysis found that expected postoperative pain and anticipated analgesic needs contributed to post-CD pain prediction modeling (R (2) = 0.443, p < 0.0001); expected postoperative pain, ASI, and FPQ were associated with opioid usage (R (2) = 0.421, p < 0.0001). Conclusion. Preoperative psychological tests combined with simple pain prediction ratings accounted for 44% and 42% of pain and analgesic use variance, respectively. Preoperatively determined expected postoperative pain and perceived analgesic needs appear to be useful predictors for post-CD pain and analgesic requirements.

  18. A Prospective Cohort Study Evaluating the Ability of Anticipated Pain, Perceived Analgesic Needs, and Psychological Traits to Predict Pain and Analgesic Usage following Cesarean Delivery

    PubMed Central

    Carvalho, Brendan; Zheng, Ming; Harter, Scott; Sultan, Pervez

    2016-01-01

    Introduction. This study aimed to determine if preoperative psychological tests combined with simple pain prediction ratings could predict pain intensity and analgesic usage following cesarean delivery (CD). Methods. 50 healthy women undergoing scheduled CD with spinal anesthesia comprised the prospective study cohort. Preoperative predictors included 4 validated psychological questionnaires (Anxiety Sensitivity Index (ASI), Fear of Pain (FPQ), Pain Catastrophizing Scale, and Eysenck Personality Questionnaire) and 3 simple ratings: expected postoperative pain (0–10), anticipated analgesic threshold (0–10), and perceived analgesic needs (0–10). Postoperative outcome measures included post-CD pain (combined rest and movement) and opioid used for the 48-hour study period. Results. Bivariate correlations were significant with expected pain and opioid usage (r = 0.349), anticipated analgesic threshold and post-CD pain (r = −0.349), and perceived analgesic needs and post-CD pain (r = 0.313). Multiple linear regression analysis found that expected postoperative pain and anticipated analgesic needs contributed to post-CD pain prediction modeling (R2 = 0.443, p < 0.0001); expected postoperative pain, ASI, and FPQ were associated with opioid usage (R2 = 0.421, p < 0.0001). Conclusion. Preoperative psychological tests combined with simple pain prediction ratings accounted for 44% and 42% of pain and analgesic use variance, respectively. Preoperatively determined expected postoperative pain and perceived analgesic needs appear to be useful predictors for post-CD pain and analgesic requirements. PMID:27143966

  19. Effectiveness of Self-Hypnosis on the Relief of Experimental Dental Pain: A Randomized Trial.

    PubMed

    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. PMID:26894422

  20. Chenopodium ambrosioides L. Reduces Synovial Inflammation and Pain in Experimental Osteoarthritis

    PubMed Central

    Calado, Gustavo P.; Lopes, Alberto Jorge O.; Costa Junior, Livio M.; Lima, Francisco das Chagas A.; Silva, Lucilene A.; Pereira, Wanderson S.; do Amaral, Flávia M. M.; Garcia, João Batista S.; Cartágenes, Maria do Socorro de S.; Nascimento, Flávia R. F.

    2015-01-01

    The chronicity of osteoarthritis (OA), characterized by pain and inflammation in the joints, is linked to a glutamate receptor, N-methyl-D-aspartate (NMDA). The use of plant species such as Chenopodium ambrosioides L. (Amaranthaceae) as NMDA antagonists offers a promising perspective. This work aims to analyze the antinociceptive and anti-inflammatory responses of the crude hydroalcoholic extract (HCE) of C. ambrosioides leaves in an experimental OA model. Wistar rats were separated into six groups (n = 24): clean (C), negative control (CTL-), positive control (CTL+), HCE0.5, HCE5 and HCE50. The first group received no intervention. The other groups received an intra-articular injection of sodium monoiodoacetate (MIA) (8 mg/kg) on day 0. After six hours, they were orally treated with saline, Maxicam plus (meloxicam + chondroitin sulfate) and HCE at doses of 0.5 mg/kg, 5 mg/kg and 50 mg/kg, respectively. After three, seven and ten days, clinical evaluations were performed (knee diameter, mechanical allodynia, mechanical hyperalgesia and motor activity). On the tenth day, after euthanasia, synovial fluid and draining lymph node were collected for cellular quantification, and cartilage was collected for histopathological analysis. Finally, molecular docking was performed to evaluate the compatibility of ascaridole, a monoterpene found in HCE, with the NMDA receptor. After the third day, HCE reduced knee edema. HCE5 showed less cellular infiltrate in the cartilage and synovium and lower intensities of allodynia from the third day and of hyperalgesia from the seventh day up to the last treatment day. The HCE5 and HCE50 groups improved in forced walking. In relation to molecular docking, ascaridole showed NMDA receptor binding affinity. C. ambrosioides HCE was effective in the treatment of OA because it reduced synovial inflammation and behavioral changes due to pain. This effect may be related to the antagonistic effect of ascaridole on the NMDA receptor. PMID:26524084

  1. Chenopodium ambrosioides L. Reduces Synovial Inflammation and Pain in Experimental Osteoarthritis.

    PubMed

    Calado, Gustavo P; Lopes, Alberto Jorge O; Costa Junior, Livio M; Lima, Francisco das Chagas A; Silva, Lucilene A; Pereira, Wanderson S; Amaral, Flávia M M do; Garcia, João Batista S; Cartágenes, Maria do Socorro de S; Nascimento, Flávia R F

    2015-01-01

    The chronicity of osteoarthritis (OA), characterized by pain and inflammation in the joints, is linked to a glutamate receptor, N-methyl-D-aspartate (NMDA). The use of plant species such as Chenopodium ambrosioides L. (Amaranthaceae) as NMDA antagonists offers a promising perspective. This work aims to analyze the antinociceptive and anti-inflammatory responses of the crude hydroalcoholic extract (HCE) of C. ambrosioides leaves in an experimental OA model. Wistar rats were separated into six groups (n = 24): clean (C), negative control (CTL-), positive control (CTL+), HCE0.5, HCE5 and HCE50. The first group received no intervention. The other groups received an intra-articular injection of sodium monoiodoacetate (MIA) (8 mg/kg) on day 0. After six hours, they were orally treated with saline, Maxicam plus (meloxicam + chondroitin sulfate) and HCE at doses of 0.5 mg/kg, 5 mg/kg and 50 mg/kg, respectively. After three, seven and ten days, clinical evaluations were performed (knee diameter, mechanical allodynia, mechanical hyperalgesia and motor activity). On the tenth day, after euthanasia, synovial fluid and draining lymph node were collected for cellular quantification, and cartilage was collected for histopathological analysis. Finally, molecular docking was performed to evaluate the compatibility of ascaridole, a monoterpene found in HCE, with the NMDA receptor. After the third day, HCE reduced knee edema. HCE5 showed less cellular infiltrate in the cartilage and synovium and lower intensities of allodynia from the third day and of hyperalgesia from the seventh day up to the last treatment day. The HCE5 and HCE50 groups improved in forced walking. In relation to molecular docking, ascaridole showed NMDA receptor binding affinity. C. ambrosioides HCE was effective in the treatment of OA because it reduced synovial inflammation and behavioral changes due to pain. This effect may be related to the antagonistic effect of ascaridole on the NMDA receptor.

  2. Physiological and Psychological Predictors of Short-Term Disability in Workers with a History of Low Back Pain: A Longitudinal Study

    PubMed Central

    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

  3. Inter-Individual Responses to Experimental Muscle Pain: Baseline Physiological Parameters Do Not Determine Whether Muscle Sympathetic Nerve Activity Increases or Decreases During Pain

    PubMed Central

    Kobuch, Sophie; Fazalbhoy, Azharuddin; Brown, Rachael; Macefield, Vaughan G.

    2015-01-01

    We have previously reported that there are inter-individual differences in the cardiovascular responses to experimental muscle pain, which are consistent over time: intramuscular infusion of hypertonic saline, causing pain lasting ~60 min, increases muscle sympathetic nerve activity (MSNA)—as well as blood pressure and heart rate—in certain subjects, but decrease it in others. Here, we tested the hypothesis that baseline physiological parameters (resting MSNA, heart rate, blood pressure, heart rate variability) determine the cardiovascular responses to long-lasting muscle pain. MSNA was recorded from the common peroneal nerve, together with heart rate and blood pressure, during a 45-min intramuscular infusion of hypertonic saline solution into the tibialis anterior of 50 awake human subjects (25 females and 25 males). Twenty-four subjects showed a sustained increase in mean amplitude of MSNA (160.9 ± 7.3%), while 26 showed a sustained decrease (55.1 ± 3.5%). Between the increasing and decreasing groups there were no differences in baseline MSNA (19.0 ± 1.5 vs. 18.9 ± 1.2 bursts/min), mean BP (88.1 ± 5.2 vs. 88.0 ± 3.8 mmHg), HR (74.7 ± 2.0 vs. 72.8 ± 1.8 beats/min) or heart rate variability (LF/HF 1.8 ± 0.2 vs. 2.2 ± 0.3). Furthermore, neither sex nor body mass index had any effect on whether MSNA increased or decreased during tonic muscle pain. We conclude that the measured baseline physiological parameters cannot account for the divergent sympathetic responses during tonic muscle pain. PMID:26733786

  4. Inter-Individual Responses to Experimental Muscle Pain: Baseline Physiological Parameters Do Not Determine Whether Muscle Sympathetic Nerve Activity Increases or Decreases During Pain.

    PubMed

    Kobuch, Sophie; Fazalbhoy, Azharuddin; Brown, Rachael; Macefield, Vaughan G

    2015-01-01

    We have previously reported that there are inter-individual differences in the cardiovascular responses to experimental muscle pain, which are consistent over time: intramuscular infusion of hypertonic saline, causing pain lasting ~60 min, increases muscle sympathetic nerve activity (MSNA)-as well as blood pressure and heart rate-in certain subjects, but decrease it in others. Here, we tested the hypothesis that baseline physiological parameters (resting MSNA, heart rate, blood pressure, heart rate variability) determine the cardiovascular responses to long-lasting muscle pain. MSNA was recorded from the common peroneal nerve, together with heart rate and blood pressure, during a 45-min intramuscular infusion of hypertonic saline solution into the tibialis anterior of 50 awake human subjects (25 females and 25 males). Twenty-four subjects showed a sustained increase in mean amplitude of MSNA (160.9 ± 7.3%), while 26 showed a sustained decrease (55.1 ± 3.5%). Between the increasing and decreasing groups there were no differences in baseline MSNA (19.0 ± 1.5 vs. 18.9 ± 1.2 bursts/min), mean BP (88.1 ± 5.2 vs. 88.0 ± 3.8 mmHg), HR (74.7 ± 2.0 vs. 72.8 ± 1.8 beats/min) or heart rate variability (LF/HF 1.8 ± 0.2 vs. 2.2 ± 0.3). Furthermore, neither sex nor body mass index had any effect on whether MSNA increased or decreased during tonic muscle pain. We conclude that the measured baseline physiological parameters cannot account for the divergent sympathetic responses during tonic muscle pain. PMID:26733786

  5. Experimental studies of glass refining

    NASA Technical Reports Server (NTRS)

    Subramanian, R. S.; Cole, R.; Kondos, P.

    1984-01-01

    The basic components of the experimental apparatus were selected and acquired. Techniques were developed for the fabrication of the special crucibles necessary for the experiments. Arrangements were made for the analysis of glass and gas bubble samples for composition information. Donations of major equipment were received for this project from Owens, Illinois where a similar study had been conducted a few year ago. Decisions were made regarding the actual glass composition to be used, the gas to be used in the first experiments, and the temperatures at which the experiments should be conducted. A microcomputer was acquired, and work was begun on interfacing the video analyzer to it.

  6. Experimental study of vortex diffusers

    SciTech Connect

    Shakerin, S.; Miller, P.L.

    1995-11-01

    This report documents experimental research performed on vortex diffusers used in ventilation and air-conditioning systems. The main objectives of the research were (1) to study the flow characteristics of isothermal jets issuing from vortex diffusers, (2) to compare the vortex diffuser`s performance with that of a conventional diffuser, and (3) to prepare a report that disseminates the results to the designers of ventilation and air-conditioning systems. The researchers considered three diffusers: a conventional round ceiling diffuser and two different styles of vortex diffusers. Overall, the vortex diffusers create slightly more induction of ambient air in comparison to the conventional diffuser.

  7. The periaqueductal gray and descending pain modulation: why should we study them and what role do they play in chronic pain?

    PubMed

    Hemington, Kasey S; Coulombe, Marie-Andrée

    2015-10-01

    In this Neuro Forum we discuss the significance of a recent study by Yu et al. (Neuroimage Clin 6: 100-108, 2014). The authors examined functional connectivity of a key node of the descending pain modulation pathway, the periaqueductal gray (PAG), in chronic back pain patients. Altered PAG connectivity to pain-related regions was found; we place results within the context of recent literature and emphasize the importance of understanding the descending component of pain in pain research.

  8. Antihyperalgesic Effect of Hesperidin Improves with Diosmin in Experimental Neuropathic Pain

    PubMed Central

    Pellicer, Francisco; López-Muñoz, Francisco J.

    2016-01-01

    Neuropathic pain is caused by a primary lesion, dysfunction, or transitory perturbation in the peripheral or central nervous system. In this study, we investigated the hesperidin antihyperalgesic effects alone or combined with diosmin in a model of neuropathic pain to corroborate a possible synergistic antinociceptive activity. Mechanical and thermal hyperalgesia were assessed in the aesthesiometer and plantar tests, respectively, after chronic constriction injury (CCI) model in rats receiving hesperidin (HS, 5 doses from 10 to 1000 mg/kg) alone or combined with diosmin (DS, 10 and 100 mg/kg) in comparison to gabapentin (31.6 mg/kg). UHPLC-MS analysis of cerebral samples was used to recognize the central concentrations of these flavonoids. Participation of different receptors was also investigated in the presence of haloperidol, bicuculline, and naloxone antagonists. Acute hesperidin administration significantly decreased mechanical and thermal hyperalgesia in CCI rats. Antihyperalgesic response of hesperidin, improved by a combination with diosmin (DS10/HS100) in both stimuli, was blockaded by haloperidol, bicuculline, and naloxone, but not WAY100635, antagonists. Both flavonoids were detected in brain samples. In conclusion, hesperidin alone and combined with diosmin produces antihyperalgesic response in the CCI model in rats. Antihyperalgesic effect of DS10/HS100 combination involves central activity partially modulated by D2, GABAA, and opioids, but not by 5-HT1A, receptors. PMID:27672659

  9. Antihyperalgesic Effect of Hesperidin Improves with Diosmin in Experimental Neuropathic Pain

    PubMed Central

    Pellicer, Francisco; López-Muñoz, Francisco J.

    2016-01-01

    Neuropathic pain is caused by a primary lesion, dysfunction, or transitory perturbation in the peripheral or central nervous system. In this study, we investigated the hesperidin antihyperalgesic effects alone or combined with diosmin in a model of neuropathic pain to corroborate a possible synergistic antinociceptive activity. Mechanical and thermal hyperalgesia were assessed in the aesthesiometer and plantar tests, respectively, after chronic constriction injury (CCI) model in rats receiving hesperidin (HS, 5 doses from 10 to 1000 mg/kg) alone or combined with diosmin (DS, 10 and 100 mg/kg) in comparison to gabapentin (31.6 mg/kg). UHPLC-MS analysis of cerebral samples was used to recognize the central concentrations of these flavonoids. Participation of different receptors was also investigated in the presence of haloperidol, bicuculline, and naloxone antagonists. Acute hesperidin administration significantly decreased mechanical and thermal hyperalgesia in CCI rats. Antihyperalgesic response of hesperidin, improved by a combination with diosmin (DS10/HS100) in both stimuli, was blockaded by haloperidol, bicuculline, and naloxone, but not WAY100635, antagonists. Both flavonoids were detected in brain samples. In conclusion, hesperidin alone and combined with diosmin produces antihyperalgesic response in the CCI model in rats. Antihyperalgesic effect of DS10/HS100 combination involves central activity partially modulated by D2, GABAA, and opioids, but not by 5-HT1A, receptors.

  10. Guided Imagery for Adolescent Post-spinal Fusion Pain Management: A Pilot Study.

    PubMed

    Charette, Sylvie; Fiola, Jacinthe Lachance; Charest, Marie-Claude; Villeneuve, Edith; Théroux, Jean; Joncas, Julie; Parent, Stefan; Le May, Sylvie

    2015-06-01

    Orthopedic surgery for adolescent idiopathic scoliosis entails anxiety and severe postoperative pain. The aim of this pilot study was to investigate an intervention for adolescent post-spinal fusion pain management in patients from a tertiary care hospital in Montreal, Canada. Participants were adolescents and young adults ages 11 to 20 years undergoing spinal fusion. Participants were randomized to standard care or standard care with adjunct intervention. The intervention consisted of a DVD with information and guided imagery/relaxation exercises to practice at least three times a week at home. A nurse screened the DVD with the patient preoperatively and at discharge (T1) and telephoned 2 weeks post-discharge (T2) to reinforce the technique. Both groups completed questionnaires at T1, T2, and T3 (1-month postoperative follow-up). Outcome measures included pain intensity, anxiety, coping mechanisms, and daily activities. From March 2010 to June 2011, we enrolled 40 of 45 eligible participants (n = 20 per group), average age 15 ± 2.1 years, 7 participants were male. Compared with the control group, the experimental group experienced significantly less overall pain at all time points, with moderate to large effect sizes at T2, T3 (p ≤ .007). Worst pain in 24 hours was moderately decreased at T2 (p = .01). State-trait anxiety remained high. On a 10-point scale, a median 2.5-point benefit was seen in eating and sleeping (Mann-Whitney test, p = .002), and 2 points in walking (Mann-Whitney test, p = .003). Coping strategies showed no significant differences. Addition of a guided imagery and relaxation exercise DVD for home use was more effective than standard care alone for postoperative pain. Our nonpharmacologic adjunct looks promising. Larger sample size and longer (6-9 months) follow-up will permit refinement. PMID:25439116

  11. Early maladaptive schema factors, chronic pain and depressiveness: a study with 271 chronic pain patients and 331 control participants.

    PubMed

    Saariaho, Tom; Saariaho, Anita; Karila, Irma; Joukamaa, Matti

    2012-01-01

    Chronic pain and depression are coexisting entities with high simultaneous prevalence. Both are linked with early adversities. Early maladaptive schemas (EMS) can be seen as a reflection of these adversities. EMSs extensively indicate underlying psychic patterns and provide a good opportunity to detect covert processes and psychic shapes (latent factors), which create the basis of how people rate their schemas. The purpose of this study was to explore these latent, higher order schema factors (SF) and to find out how they are associated with pain intensity or depression in chronic pain patients and a control sample. The study subjects consisted of 271 first-visit pain patients and 331 control participants. Sociodemographic and pain data were gathered by questionnaire; 18 EMSs were measured with the Young Schema Questionnaire (short form) and depressiveness was measured with the Beck Depression Inventory, Version II. Exploratory factor and regression analyses were used. The chronic pain patient group showed two SFs. The first SF showed a shameful, defective, socially isolated, failure, emotionally inhibited, deprived, submissive and resigned pattern. The second SF showed a demanding, approval seeking, self-sacrificing and punitive pattern. SF1 predicted more than half of the depressiveness in the pain patient sample. A three-factor structure was found in the control sample, and SFs 1 and 3 together predicted almost one-third of depressiveness. The pain patient and the control groups had a different, higher order factor structure. We assume that SF1 in the pain patients reflected a rather serious, undefined early psychic trauma and was also associated with their depressiveness. PMID:21210495

  12. Experimental studies with palygorskite dusts.

    PubMed

    Wagner, J C; Griffiths, D M; Munday, D E

    1987-11-01

    As the preliminary results of experimental studies on dust from the palygorskite group have led to some confusion a detailed description of the completed investigation is given for clarification. As in other experiments the biological effects have been shown to be associated with the physical characteristics of the fibres in these specimens. Samples of sepiolite and attapulgite from Spain and a single sample of palygorskite from the United Kingdom have been studied. Serious abnormalities were produced only by the palygorskite and one of the attapulgite dusts. The palygorskite is of no commercial interest and the attapulgite was from one small deposit and was used only in the preparation of drilling mud in the exploration of oil deposits. PMID:2961365

  13. Psychosocial criteria for patient selection: review of studies and concepts for understanding chronic back pain.

    PubMed

    Keel, P J

    1984-12-01

    Eighteen studies on psychosocial aspects of back pain are reviewed. Among six studies trying to differentiate pain of organic and functional origin, only two studies claim to be able to make such a distinction. Psychological disturbance--studied with a variety of instruments--proved to be an important factor affecting the reporting and measurement of pain (eight studies). Low disturbance can predict good outcome in both organic and functional pain (six studies). Psychological disturbance, however, seems to be equally the consequence and the cause of pain, and pain relief reduces psychological disturbance. Thus, the dichotomy of organic vs. psychogenic pain must be dismissed, and a holistic, interactive systems model must be advocated. Factors causing acute back pain should be differentiated from those leading to chronicity. A model for understanding the evolution of chronicity and a checklist for possible factors promoting chronicity are presented. PMID:6239990

  14. Natural course of acute neck and low back pain in the general population: the HUNT study.

    PubMed

    Vasseljen, Ottar; Woodhouse, Astrid; Bjørngaard, Johan Håkon; Leivseth, Linda

    2013-08-01

    In this prospective cohort study we aimed to describe the natural course of acute neck and low back pain in a general population of Norway. We screened 9056 subjects aged 20-67 years who participated in a general health survey for a new episode of neck or low back pain the previous month. The screening identified 219 subjects who formed the cohort for this study. Pain intensity was reported on a numeric rating scale (0-10) at 1, 2, 3, 6, and 12 months after start of the new pain episode. The course of pain was described for neck and low back pain, different baseline pain levels, age groups, and number of pain sites at baseline. Use of medication and health care was described and associations between pain intensity and seeking health care were estimated. Pain declined rapidly within 1 month after a new pain episode, with a reduction of 0.91 (95% confidence interval [CI] 0.50-1.32) for neck pain and 1.40 (95% CI 0.82-1.99) for low back pain with little change thereafter. However, pain remained unchanged over the follow-up year for those with equal pain in the neck and low back areas at baseline and for those reporting 4 or more pain sites at baseline. Only 1 in 5 sought health care for their complaints. Still, the course of pain was comparable to effect sizes reported in interventional studies. This study thus contributes natural course reference data for comparisons of pain outcome in clinical trials and practice.

  15. Effectiveness of preoperative analgesics on postoperative dental pain: a study.

    PubMed Central

    Zacharias, M.; Hunter, K. M.; Baker, A. B.

    1996-01-01

    Patients undergoing extractions of third molar teeth under general anesthesia were given a placebo, diclofenac (a nonsteroidal anti-inflammatory drug) 100 mg, or methadone (an opiate) 10 mg 60 to 90 min prior to surgery, and their pain scores and postoperative medication requirements were measured for 3 days. All patients received local anesthetic blocks and analgesic drugs during the perioperative period. There were no significant differences between the three groups in the pain scores and medication requirements during the period of study. It was concluded that preoperative use of nonsteroidal anti-inflammatory drugs and opiates may not offer a preemptive analgesic effect in patients who have had adequate analgesia during the surgery. Continued use of analgesic drugs during the postoperative period is perhaps more useful for this purpose. There appears to be a higher incidence of vomiting following opiates (methadone), precluding its clinical use in day-care patients. PMID:10323113

  16. Motor performance in chronic low back pain: is there an influence of pain-related cognitions? A pilot study

    PubMed Central

    2011-01-01

    Background Chronic low back pain (CLBP) is often accompanied by an abnormal motor performance. However, it has not been clarified yet whether these deviations also occur during motor tasks not involving the back and whether the performance is influenced by pain and pain-related cognitions. Therefore, the aim of the present study is to get insight in the contribution of both pain experience and pain-related cognitions to general motor task performance in CLBP. Methods 13 CLBP patients and 15 healthy subjects performed a hand-function task in three conditions: sitting, lying prone (lying) and lying prone without trunk support (provoking). The last condition was assumed to provoke pain-related cognitions, which was considered successful when a patients' pain expectancy on a numeric rating scale was at least 1 point higher than actual pain experienced. Subjects' performance was expressed in reaction time and movement time. Repeated measures analysis of variance was performed to detect main effect for group and condition. Special interest was given to group*condition interaction, since significant interaction would indicate that patients and healthy subjects performed differently throughout the three conditions. Results Patients were slower throughout all conditions compared to healthy subjects. With respect to the provoking condition, patients showed deteriorated performance compared to lying while healthy subjects' performance remained equal between these two conditions. Further analysis of patients' data showed that provocation was successful in 54% of the patients. Especially this group showed deteriorated performance in the provoking condition. Conclusion It can be concluded that CLBP patients in general have worse motor task performance compared to healthy subjects and that provoking pain-related cognitions further worsened performance. PMID:21951591

  17. Positive Traits Linked to Less Pain through Lower Pain Catastrophizing

    PubMed Central

    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

  18. Understanding pain and improving management of sickle cell disease: the PiSCES study.

    PubMed Central

    Smith, Wally R.; Bovbjerg, Viktor E.; Penberthy, Lynne T.; McClish, Donna K.; Levenson, James L.; Roberts, John D.; Gil, Karen; Roseff, Susan D.; Aisiku, Imoigele P.

    2005-01-01

    Until recent decades, sickle cell disease (SCD) was associated with recurrent, disabling pain, organ failure and death in childhood or early adulthood. SCD treatment advances have now decreased pain and prolonged survival, but episodic or chronic pain may still require substantial analgesic use and frequent hospitalization for pain episodes. This pain is poorly characterized and often poorly treated. Adult patients may face barriers to comprehensive SCD care, stigmatization of their care-seeking behavior by providers and lack of family support, forcing them into maladaptive coping strategies. The Pain in Sickle Cell Epidemiology Study (PiSCES) attempts to develop and validate a biopsychosocial model of SCD pain, pain response and healthcare utilization in a large, multisite adult cohort. PiSCES participants complete a baseline survey and six months of daily pain diaries in which they record levels of SCD-related pain and related disability and distress as well as responses to pain (e.g., medication use, hospital visits). PiSCES will advance methods of measuring pain and pain response in SCD by better describing home-managed as well as provider-managed pain. PiSCES will assess the relative contributions of biological (disease-related), psychosocial and environmental (readiness to utilize) factors to overall pain and pain response in SCD, suggesting targets for biobehavioral interventions over time. Importantly, PiSCES will also identify "triggers" of SCD pain episodes and healthcare utilization in the moment of pain, suggesting targets for timely care that mutes pain episodes. Images Figure 1 Figure 2 PMID:15712781

  19. A connectionist modeling study of the neural mechanisms underlying pain's ability to reorient attention.

    PubMed

    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. PMID:27112345

  20. The Efficacy of Thermotherapy and Cryotherapy on Pain Relief in Patients with Acute Low Back Pain, A Clinical Trial Study

    PubMed Central

    Dehghan, Morteza

    2014-01-01

    Introduction: Acute low back pain is one of the most common health problems especially in industrialized countries where 75 per cent of the population develop it at least once during their life. This study examined the efficacy of thermotherapy and cryotherapy, alongside a routine pharmacologic treatment, on pain relief in patients with acute low back pain referring an orthopedic clinic in Shahrekord, Iran. Materials and Methods: This clinical trial study was conducted on 87 patients randomly assigned to three (thermotherapy and cryotherapy as intervention, and naproxen as control) groups of 29 each. The first (thermotherapy) group underwent treatment with hot water bag and naproxen, the second (cryotherapy) group was treated with ice and naproxen, and the naproxen group was only treated with naproxen, all for one week. All patients were examined on 0, 3rd, 8th, and 15th day after the first visit and the data gathered by McGill Pain Questionnaire. The data were analyzed by SPSS software using paired t-test, ANOVA, and chi-square. Results: In this study, mean age of the patients was 34.48 (20–50) years and 51.72 per cent were female. Thermotherapy patients reported significantly less pain compared to cryotherapy and control (p≤0.05). In thermotherapy and cryotherapy groups, mean pain in the first visit was 12.70±3.7 and 12.06±2.6, and on the 15th day after intervention 0.75±0.37 and 2.20±2.12, respectively. Conclusion: The results indicated that the application of thermo–therapy and cryotherapy accompanied with a pharmacologic treatment could relieve pain in the patients with acute low back pain. PMID:25386469

  1. Pain Assessment and Management in Critically ill Intubated Patients in Jordan: A Prospective Study

    PubMed Central

    Ayasrah, Shahnaz Mohammad; O’Neill, Teresa Mary; Abdalrahim, Maysoon Saleem; Sutary, Manal Mohammed; Kharabsheh, Muna Suliman

    2014-01-01

    Objectives The purpose of this study was to describe: (1) pain indicators used by nurses and physicians to assess pain, (2) pain management interventions (pharmacological and non-pharmacological) used by nurses, and (3) indicators used by nurses to verify pain intervention effectiveness. Methodology A total of 301 medical records of currently admitted patients from six different ICUs in Jordan were reviewed using a data collection instrument developed by Gélinas et al. (2004) Pain-related indicators were classified into non-observable (patient’s self-reports of pain) and observable (physiological and behavioral) categories. Results Only 105 (35%) of a total 301 reviewed medical records contained pain assessment data. From these medical records, 15 pain episodes were collected altogether. Observable indicators documented 98% of the 115 pain episodes. Patients’ self-reports of pain were documented only 1.7% of the time. In 78% and 46% of the 115 pain episodes, pharmacological and nonpharmacological interventions for pain management were documented, respectively. Only 37% of the pain episodes were reassessed with self- report (1%) and observable indicators (36%) to determine the effectiveness of the interventions. Conclusion Pain documentation for assessment, management, and reassessment was lacking and needs improvement. PMID:25505864

  2. Underestimation and undertreatment of pain in HIV disease: multicentre study.

    PubMed Central

    Larue, F.; Fontaine, A.; Colleau, S. M.

    1997-01-01

    OBJECTIVE: To measure the prevalence, severity, and impact of pain on quality of life for HIV patients; to identify factors associated with undertreatment of pain. DESIGN: Multicentre cross sectional survey. SETTINGS: 34 HIV treatment facilities, including inpatient hospital wards, day hospitals, and ambulatory care clinics, in 13 cities throughout France. SUBJECTS: 315 HIV patients at different stages of the disease. MAIN OUTCOME MEASURES: Patients: recorded presence and severity of pain and rated quality of life. Doctors: reported disease status, estimate of pain severity, and analgesic treatment ordered. RESULTS: From 30% (17/56) of outpatients to 62% (73/118) of inpatients reported pain due to HIV disease. Pain severity significantly decreased patients' quality of life. Doctors underestimated pain severity in 52% (70/135) of HIV patients reporting pain. Underestimation of pain severity was more likely for patients who reported moderate (odds ratio 24) or severe pain (165) and less likely for patients whose pain source was identified or who were perceived as more depressed. Of the patients reporting moderate or severe pain, 57% (61/107) did not receive any analgesic treatment; only 22% (23/107) received at least weak opioids. Likelihood of analgesic prescription increased when doctors estimated pain to be more severe and regarded patients as sicker. CONCLUSIONS: Pain is a common and debilitating symptom of HIV disease which is gravely underestimated and undertreated. PMID:9001475

  3. The “at-home LLLT” in temporo-mandibular disorders pain control: a pilot study

    PubMed Central

    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

  4. The role of operant conditioning in chronic pain: an experimental investigation.

    PubMed

    Flor, Herta; Knost, Bärbel; Birbaumer, Niels

    2002-01-01

    The role of operant conditioning for the development and maintenance of chronic pain was examined in 30 chronic back pain patients (CBP) and 30 matched healthy controls. Half of each group was reinforced for increased, half for decreased pain reports while EEG, EOG, heart rate, skin conductance and muscle tension levels were recorded. Both groups showed similar learning rates, however, the CBP patients displayed slower extinction of both the verbal and the cortical (N150) pain response. In addition, the CBP group displayed prolonged elevated electromyogram levels to the task. These data suggest that CBP patients are more easily influenced by operant conditioning factors than healthy controls and this susceptibility may add to the maintenance of the chronic pain problem.

  5. Improving undergraduate medical education about pain assessment and management: A qualitative descriptive study of stakeholders’ perceptions

    PubMed Central

    Tellier, Pierre-Paul; Bélanger, Emmanuelle; Rodríguez, Charo; Ware, Mark A; Posel, Nancy

    2013-01-01

    BACKGROUND Pain is one of the most common reasons for individuals to seek medical advice, yet it remains poorly managed. One of the main reasons that poor pain management persists is the lack of adequate knowledge and skills of practicing clinicians, which stems from a perceived lack of pain education during the training of undergraduate medical students. OBJECTIVE: To identify gaps in knowledge with respect to pain management as perceived by students, patients and educators. METHODS: A qualitative descriptive study was conducted. Data were generated through six focus groups with second- and fourth-year medical students, four focus groups with patients and individual semistructured interviews with nine educators. All interviews were audiotaped and an inductive thematic analysis was performed. RESULTS: A total of 70 individuals participated in the present study. Five main themes were identified: assessment of physical and psychosocial aspects of pain; clinical management of pain with pharmacology and alternative therapies; communication and the development of a good therapeutic relationship; ethical considerations surrounding pain; and institutional context of medical education about pain. CONCLUSION: Participating patients, students and pain experts recognized a need for additional medical education about pain assessment and management. Educational approaches need to teach students to gather appropriate information about pain, to acquire knowledge of a broad spectrum of therapeutic options, to develop a mutual, trusting relationship with patients and to become aware of their own biases and prejudice toward patients with pain. The results of the present study should be used to develop and enhance existing pain curricula content. PMID:23985579

  6. Cancer Health Empowerment for Living without Pain (Ca-HELP): study design and rationale for a tailored education and coaching intervention to enhance care of cancer-related pain

    PubMed Central

    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

  7. Pain Characteristics Associated With the Onset of Disability in Older Adults: The MOBILIZE Boston Study

    PubMed Central

    Eggermont, Laura H.P.; Leveille, Suzanne G.; Shi, Ling; Kiely, Dan K.; Shmerling, Robert H.; Jones, Rich N.; Guralnik, Jack M.; Bean, Jonathan F.

    2014-01-01

    Background/Objectives To determine the effects of chronic pain on the development of disability and decline in physical performance over time among older adults. Design Longitudinal cohort study with 18 months follow-up. Setting Urban/suburban communities Participants 634 community-dwelling older adults aged >64 years. Measurements Chronic pain assessment consisted of musculoskeletal pain locations, and pain severity and pain interference by subscales of the Brief Pain Inventory. Disability was self-reported as any difficulty in mobility and basic and instrumental activities of daily living (ADL, IADL). Mobility performance was measured using the Short Physical Performance Battery (SPPB). Relationships between baseline pain and incident disability in 18 months were determined using risk ratios (RRs) from multivariable Poisson regression models. Results Almost 65% of participants reported chronic musculoskeletal pain at baseline. New onset of mobility difficulty at 18-months was strongly associated with baseline pain distribution: 7% (no sites), 18% (1 site), 24% (multisite) and 39% (widespread pain, p-value for trend <0.001). Similar graded effects were found for other disability measures. Elders with multisite or widespread pain had at least a three-fold increased risk for onset of mobility difficulty compared to their peers without pain after adjusting for disability risk factors (multisite pain: RR=2.95, 95%CI, 1.58–5.50; widespread pain: RR=3.57, 95%CI, 1.71–7.48). Widespread pain contributed to decline in mobility performance (1 point decline in SPPB, RR=1.47, 95%CI, 1.08–2.01). Similar associations were found for baseline pain interference predicting subsequent mobility decline and (I)ADL disability. Weaker and less consistent associations were observed with pain severity. Conclusion Older community-dwelling adults living with chronic pain in multiple musculoskeletal locations have a substantial increased risk for developing disability over time and for

  8. Low-level laser therapy, at 830 nm, for pain reduction in experimental model of rats with sciatica.

    PubMed

    Bertolini, Gladson Ricardo Flor; Artifon, Elisangela Lourdes; Silva, Taciane Stein da; Cunha, Daniela Martins; Vigo, Priscila Regina

    2011-01-01

    Chronic pain, resulting from nerve compression, is a common clinical presentation. One means of conservative treatment is low-level laser therapy, although controversial. The aim of this study was to evaluate the effects of two doses of low-level laser, at 830 nm, on pain reduction in animals subjected to sciatica. Eighteen rats were used, divided into three groups: GS (n=6), sciatica and simulated treatment; G4J (n=6), sciatica and treatment with 4 J/cm²; and G8J (n=6), sciatica and irradiation with 8 J/cm². The right sciatic nerve was exposed and compressed using catgut thread. Five days of treatment were started on the third postoperative day. Pain was assessed by means of the paw elevation time during gait: before sciatica, before and after the first and second therapies, and the end of the fifth therapy. Low-level laser was effective in reducing the painful condition.

  9. A study of patient experience and perception regarding postoperative pain management in Chinese hospitals

    PubMed Central

    Weiran, Liu; Lei, Zhang; Woo, Stephanie Mu-Lian; Anliu, Tang; Shumin, Xie; Jing, Zhang; Kai, Zhang; Zhen, Zhang

    2013-01-01

    Background This study aims to analyze the current status of postoperative pain management in the People’s Republic of China’s provincial-level hospitals, and the existing knowledge and opinions held by patients regarding these methods. Methods The 128 participants in this study were urology and hepatobiliary patients from three provincial-level hospitals in Hunan. The questionnaire assessing postoperative pain was designed using the typical pain assessment scales and pain management guidelines as references. Results 82.8% of study participants claimed that their postoperative pain was relieved within 3 days of their operations. However, while 91.4% of surveyed patients experienced moderate to severe pain, 51.6% received no treatment for their postoperative pain, and 14.9% complained that medical personnel failed to manage their pain. 20.2% were unsatisfied with their pain management, indicating that treatment did not meet their expectations. Furthermore, participants demonstrated a great misunderstanding of pain and analgesics, as 72.6% of patients were unfamiliar with morphine, 51.6% of patients believed only certain types of pain required management, and 18.5% refused to use morphine. Conclusion In most Chinese provincial-level hospitals, current postoperative pain management methods are able to alleviate the pain experienced by the majority of patients, though pain assessment and therapy procedures are still not standardized. Furthermore, most patients lack a proper understanding of postoperative pain and analgesics. Therefore, pain management education for doctors and patients and their relatives should be implemented in order to improve the quality of postoperative pain management. PMID:24235819

  10. Pain Reduction in Myofascial Pain Syndrome by Anodal Transcranial Direct Current Stimulation Combined with Standard Treatment: A Randomized Controlled Study

    PubMed Central

    Sakrajai, Piyaraid; Janyacharoen, Taweesak; Jensen, Mark P.; Sawanyawisuth, Kittisak; Auvichayapat, Narong; Tunkamnerdthai, Orathai; Keeratitanont, Keattichai; Auvichayapat, Paradee

    2014-01-01

    Background Myofascial pain syndrome (MPS) in the shoulder is among the most prevalent pain problems in the middle-aged population worldwide. Evidence suggests that peripheral and central sensitization may play an important role in the development and maintenance of shoulder MPS. Given previous research supporting the potential efficacy of anodal transcranial direct current stimulation (tDCS) for modulating pain-related brain activity in individuals with refractory central pain, we hypothesized that anodal tDCS when applied over the primary motor cortex (M1) combined with standard treatment will be more effective for reducing pain in patients with MPS than standard treatment alone. Method Study participants were randomized to receive either (1) standard treatment with 5-consecutive days of 1 mA anodal tDCS over M1 for 20 min or (2) standard treatment plus sham tDCS. Measures of pain intensity, shoulder passive range of motion, analgesic medication use, and self-reported physical functioning were administered before treatment and again at post-treatment and 1-, 2-, 3-and 4-week follow-up. Results Thirty-one patients with MPS were enrolled. Participants assigned to the active tDCS condition reported significantly more pre- to post-treatment reductions in pain intensity that were maintained at 1-week post-treatment, and significant improvement in shoulder adduction PROM at 1-week follow-up than participants assigned to the sham tDCS condition. Conclusion 5 consecutive days of anodal tDCS over M1 combined with standard treatment appears to reduce pain intensity, and may improve PROM, faster than standard treatment alone. Further tests of the efficacy and duration of effects of tDCS in the treatment of MPS are warranted. PMID:25373724

  11. Cost-Saving Early Diagnosis of Functional Pain in Nonmalignant Pain: A Noninferiority Study of Diagnostic Accuracy

    PubMed Central

    Cámara, Rafael J. A.; Merz, Christian; von Känel, Roland; Egloff, Niklaus

    2016-01-01

    Objectives. We compared two index screening tests for early diagnosis of functional pain: pressure pain measurement by electronic diagnostic equipment, which is accurate but too specialized for primary health care, versus peg testing, which is cost-saving and more easily manageable but of unknown sensitivity and specificity. Early distinction of functional (altered pain perception; nervous sensitization) from neuropathic or nociceptive pain improves pain management. Methods. Clinicians blinded for the index screening tests assessed the reference standard of this noninferiority diagnostic accuracy study, namely, comprehensive medical history taking with all previous findings and treatment outcomes. All consenting patients referred to a university hospital for nonmalignant musculoskeletal pain participated. The main analysis compared the receiver operating characteristic (ROC) curves of both index screening tests. Results. The area under the ROC curve for peg testing was not inferior to that of electronic equipment: it was at least 95% as large for finger measures (two-sided p = 0.038) and at least equally as large for ear measures (two-sided p = 0.003). Conclusions. Routine diagnostic testing by peg, which is accessible for general practitioners, is at least as accurate as specialized equipment. This may shorten time-to-treatment in general practices, thereby improving the prognosis and quality of life. PMID:27088013

  12. Prognosis of acute low back pain: design of a prospective inception cohort study

    PubMed Central

    Henschke, Nicholas; Maher, Christopher G; Refshauge, Kathryn M; Herbert, Robert D; Cumming, Robert G; Bleasel, Jane; York, John; Das, Anurina; McAuley, James H

    2006-01-01

    Background Clinical guidelines generally portray acute low back pain as a benign and self-limiting condition. However, evidence about the clinical course of acute low back pain is contradictory and the risk of subsequently developing chronic low back pain remains uncertain. There are few high quality prognosis studies and none that have measured pain, disability and return to work over a 12 month period. This study aims to provide the first estimates of the one year prognosis of acute low back pain (pain of less than 2 weeks duration) in patients consulting primary care practitioners. A secondary aim is to identify factors that are associated with the prognosis of low back pain. Methods/Design The study is a prospective inception cohort study. Consecutive patients consulting general medical practitioners, physiotherapists and chiropractors in the Sydney metropolitan region will complete a baseline questionnaire regarding their back pain. Subsequently these patients will be followed up by telephone 6 weeks, 3 months and 12 months after the initial consultation. Patients will be considered to have recovered from the episode of back pain if they have no pain and no limitation of activity, and have returned to pre-injury work status. Life tables will be generated to determine the one year prognosis of acute low back pain. Prognostic factors will be assessed using Cox regression. Discussion This study will provide the first estimates of the one year prognosis of acute low back pain in a representative sample of primary care patients. PMID:16790069

  13. Study Suggests Brain Is Hard-Wired for Chronic Pain

    MedlinePlus

    ... predict whether a subject would recover from low back pain. Red dots represent differences in white matter structure ... predict whether a person will suffer chronic low back pain, according to researchers who used brain scans. The ...

  14. Inverted annular flow experimental study

    SciTech Connect

    De Jarlais, G.; Ishii, M.

    1985-04-01

    Steady-state inverted annular flow of Freon 113 in up flow was established in a transparent test section. Using a special inlet configuration consisting of long aspect-ratio liquid nozzles coaxially centered within a heated quartz tube, idealized inverted annular flow initial geometry (cylindrical liquid core surrounded by coaxial annulus of gas) could be established. Inlet liquid and gas flowrates, liquid subcooling, and gas density (using various gas species) were measured and varied systematically. The hydrodynamic behavior of the liquid core, and the subsequent downstream break-up of this core into slugs, ligaments and/or droplets of various sizes, was observed. In general, for low inlet liquid velocities it was observed that after the initial formation of roll waves on the liquid core surface, an agitated region of high surface area, with attendant high momentum and energy transfers, occurs. This agitated region appears to propagate downsteam in a quasi-periodic pattern. Increased inlet liquid flow rates, and high gas annulus flow rates tend to diminish the significance of this agitated region. Observed inverted annular flow (and subsequent downstream flow pattern) hydrodynamic behavior is reported, and comparisons are drawn to data generated by previous experimenters studying post-CHF flow.

  15. The relationship between knowledge of pain neurophysiology and fear avoidance in people with chronic pain: A point in time, observational study.

    PubMed

    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. PMID:27049810

  16. The relationship between knowledge of pain neurophysiology and fear avoidance in people with chronic pain: A point in time, observational study.

    PubMed

    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.

  17. Factorial Structure of the Pain Rehabilitation Expectations Scale: A Preliminary Study

    ERIC Educational Resources Information Center

    Cheing, Gladys L. Y.; Lai, Amy K. M.; Vong, Sinfia K. S.; Chan, Fong H.

    2010-01-01

    The aim of this study was to report the preliminary validation results for the Pain Rehabilitation Expectations Scale (PRES). The PRES is a clinical tool developed to measure the expectations about rehabilitation treatment and outcome for people with back pain. Fifty people with chronic back pain were recruited from 11 physiotherapy outpatient…

  18. Pain Sensitisation in Women with Active Rheumatoid Arthritis: A Comparative Cross-Sectional Study

    PubMed Central

    Vladimirova, Nora; Jespersen, Anders; Bartels, Else Marie; Christensen, Anton W.; Bliddal, Henning; Danneskiold-Samsøe, Bente

    2015-01-01

    Objectives. In some rheumatoid arthritis (RA) patients, joint pain persists without signs of inflammation. This indicates that central pain sensitisation may play a role in the generation of chronic pain in a subgroup of RA. Our aim was to assess the degree of peripheral and central pain sensitisation in women with active RA compared to healthy controls (HC). Methods. 38 women with active RA (DAS28 > 2.6) and 38 female HC were included in, and completed, the study. Exclusion criteria were polyneuropathy, pregnancy, and no Danish language. Cuff Pressure Algometry measurements were carried out on the dominant lower leg. Pain threshold, pain tolerance, and pain sensitivity during tonic painful stimulation were recorded. Results. Women with active RA had significantly lower pain threshold (p < 0.01) and pain tolerance (p < 0.01) than HC. The mean temporal summation- (TS-) index in RA patients was 0.98 (SEM: 0.09) and 0.71 (SEM: 0.04) in HC (p < 0.01). Conclusion. Patients with active RA showed decreased pressure-pain threshold compared to HC. In addition, temporal summation of pressure-pain was increased, indicating central pain sensitization, at least in some patients. Defining this subgroup of patients may be of importance when considering treatment strategies. PMID:26266046

  19. Pain Sensitisation in Women with Active Rheumatoid Arthritis: A Comparative Cross-Sectional Study.

    PubMed

    Vladimirova, Nora; Jespersen, Anders; Bartels, Else Marie; Christensen, Anton W; Bliddal, Henning; Danneskiold-Samsøe, Bente

    2015-01-01

    Objectives. In some rheumatoid arthritis (RA) patients, joint pain persists without signs of inflammation. This indicates that central pain sensitisation may play a role in the generation of chronic pain in a subgroup of RA. Our aim was to assess the degree of peripheral and central pain sensitisation in women with active RA compared to healthy controls (HC). Methods. 38 women with active RA (DAS28 > 2.6) and 38 female HC were included in, and completed, the study. Exclusion criteria were polyneuropathy, pregnancy, and no Danish language. Cuff Pressure Algometry measurements were carried out on the dominant lower leg. Pain threshold, pain tolerance, and pain sensitivity during tonic painful stimulation were recorded. Results. Women with active RA had significantly lower pain threshold (p < 0.01) and pain tolerance (p < 0.01) than HC. The mean temporal summation- (TS-) index in RA patients was 0.98 (SEM: 0.09) and 0.71 (SEM: 0.04) in HC (p < 0.01). Conclusion. Patients with active RA showed decreased pressure-pain threshold compared to HC. In addition, temporal summation of pressure-pain was increased, indicating central pain sensitization, at least in some patients. Defining this subgroup of patients may be of importance when considering treatment strategies. PMID:26266046

  20. Pain Self-Management in HIV-infected Individuals with Chronic Pain: A Qualitative Study

    PubMed Central

    Merlin, Jessica S.; Walcott, Melonie; Kerns, Robert; Bair, Matthew J.; Burgio, Kathryn L.; Turan, Janet M.

    2015-01-01

    Objective Chronic pain in individuals with HIV is a common, impairing condition. Behavioral interventions for chronic pain specifically tailored to this population have yet to be developed. We assert that understanding self-management strategies already used by persons living with these conditions is an essential first step, and is the objective of this investigation. Design We conducted a thematic analysis of qualitative data from 25 in-depth interviews with individuals with HIV and chronic pain. Results The primary pain self-management strategies articulated by participants were: physical activity; cognitive and spiritual strategies; spending time with family and friends and social support; avoidance of physical/social activity; medication-centric pain management; and substance use. Conclusions Some of these strategies may be viewed as beneficial and overlap with known HIV self-management strategies (cognitive strategies), whereas others may have negative health consequences (substance use). Interventions that incorporate healthy self-management strategies may be particularly effective in improving both HIV and pain outcomes. PMID:25645646

  1. A magnetoencephalography study of visual processing of pain anticipation.

    PubMed

    Machado, Andre G; Gopalakrishnan, Raghavan; Plow, Ela B; Burgess, Richard C; Mosher, John C

    2014-07-15

    Anticipating pain is important for avoiding injury; however, in chronic pain patients, anticipatory behavior can become maladaptive, leading to sensitization and limiting function. Knowledge of networks involved in pain anticipation and conditioning over time could help devise novel, better-targeted therapies. With the use of magnetoencephalography, we evaluated in 10 healthy subjects the neural processing of pain anticipation. Anticipatory cortical activity elicited by consecutive visual cues that signified imminent painful stimulus was compared with cues signifying nonpainful and no stimulus. We found that the neural processing of visually evoked pain anticipation involves the primary visual cortex along with cingulate and frontal regions. Visual cortex could quickly and independently encode and discriminate between visual cues associated with pain anticipation and no pain during preconscious phases following object presentation. When evaluating the effect of task repetition on participating cortical areas, we found that activity of prefrontal and cingulate regions was mostly prominent early on when subjects were still naive to a cue's contextual meaning. Visual cortical activity was significant throughout later phases. Although visual cortex may precisely and time efficiently decode cues anticipating pain or no pain, prefrontal areas establish the context associated with each cue. These findings have important implications toward processes involved in pain anticipation and maladaptive pain conditioning.

  2. A magnetoencephalography study of visual processing of pain anticipation

    PubMed Central

    Gopalakrishnan, Raghavan; Plow, Ela B.; Burgess, Richard C.; Mosher, John C.

    2014-01-01

    Anticipating pain is important for avoiding injury; however, in chronic pain patients, anticipatory behavior can become maladaptive, leading to sensitization and limiting function. Knowledge of networks involved in pain anticipation and conditioning over time could help devise novel, better-targeted therapies. With the use of magnetoencephalography, we evaluated in 10 healthy subjects the neural processing of pain anticipation. Anticipatory cortical activity elicited by consecutive visual cues that signified imminent painful stimulus was compared with cues signifying nonpainful and no stimulus. We found that the neural processing of visually evoked pain anticipation involves the primary visual cortex along with cingulate and frontal regions. Visual cortex could quickly and independently encode and discriminate between visual cues associated with pain anticipation and no pain during preconscious phases following object presentation. When evaluating the effect of task repetition on participating cortical areas, we found that activity of prefrontal and cingulate regions was mostly prominent early on when subjects were still naive to a cue's contextual meaning. Visual cortical activity was significant throughout later phases. Although visual cortex may precisely and time efficiently decode cues anticipating pain or no pain, prefrontal areas establish the context associated with each cue. These findings have important implications toward processes involved in pain anticipation and maladaptive pain conditioning. PMID:24790165

  3. Intrinsic Brain Connectivity in Chronic Pain: A Resting-State fMRI Study in Patients with Rheumatoid Arthritis

    PubMed Central

    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

  4. Impaired psychomotor ability and attention in patients with persistent pain: a cross-sectional comparative study

    PubMed Central

    Gunnarsson, Helena; Grahn, Birgitta; Agerström, Jens

    2016-01-01

    Background and aims Patients with pain have shown cognitive impairment across various domains. Although the pain qualities vary among patients, research has overlooked how cognitive performance is affected by the duration and persistence of pain. The current study sought to fill this gap by examining how qualitatively different pain states relate to the following cognitive functions: sustained attention, cognitive control, and psychomotor ability. Patients and methods Patients with musculoskeletal pain in primary care were divided into three pain groups: acute pain (duration <3 months), regularly recurrent pain (duration >3 months), and persistent pain (duration >3 months). These groups were then compared with healthy controls. The MapCog Spectra Test, the Color Word Test, and the Grooved Pegboard Test were used to measure sustained attention, cognitive control, and psychomotor ability, respectively. Results Patients with persistent pain showed significantly worse sustained attention and psychomotor ability compared with healthy controls. The acute pain group showed a significant decrease in psychomotor ability, and the regularly recurrent pain group showed a significant decrease in sustained attention. These results remained unchanged when age, education, and medication were taken into account. Conclusion Persistent musculoskeletal pain seems to impair performance on a wider range of cognitive tasks than acute or regularly recurrent pain, using pain-free individuals as a benchmark. However, there is some evidence of impairment in psychomotor ability among patients with acute pain and some impairment in sustained attention among patients with regularly recurrent pain. Implications Caregivers may need to adjust communication methods when delivering information to cognitively impaired patients. PMID:27799814

  5. Associations Between Vitamin D Status and Pain in Older Adults: The Invecchiare in Chianti Study

    PubMed Central

    Hicks, Gregory E.; Shardell, Michelle; Miller, Ram R.; Bandinelli, Stefania; Guralnik, Jack; Cherubini, Antonio; Lauretani, Fulvio; Ferrucci, Luigi

    2009-01-01

    OBJECTIVES To examine cross-sectional associations between vitamin D status and musculoskeletal pain and whether they differ by sex. DESIGN Population-based study of persons living in the Chianti geographic area (Tuscany, Italy). SETTING Community. PARTICIPANTS Nine hundred fifty-eight persons (aged ≥65) selected from city registries of Greve and Bagno a Ripoli. MEASUREMENTS Pain was categorized as mild or no pain in the lower extremities and back; moderate to severe back pain, no lower extremity pain; moderate to severe lower extremity pain, no back pain; and moderate to severe lower extremity and back pain (dual region). Vitamin D was measured according to radioimmunoassay, and deficiency was defined as 25-hydroxyvitamin D (25(OH)D) less than 25 nmol/L. RESULTS The mean age ± standard deviation was 75.1 ± 7.3 for women and 73.9 ± 6.8 for men. Fifty-eight percent of women had at least moderate pain in some location, compared with 27% of men. After adjusting for potential confounders, vitamin D deficiency was not associated with lower extremity pain or dual-region pain, although it was associated with a significantly higher prevalence of at least moderate back pain without lower extremity pain in women (odds ratio = 1.96, 95% confidence interval = 1.01–3.59) but not in men. CONCLUSION Lower concentrations of 25(OH)D are associated with significant back pain in older women but not men. Because vitamin D deficiency and chronic pain are fairly prevalent in older adults, these findings suggest it may be worthwhile to query older adults about their pain and screen older women with significant back pain for vitamin D deficiency. PMID:18331295

  6. Hypovitaminosis D in widespread pain: its effect on pain perception, quality of life and nerve conduction studies.

    PubMed

    Kuru, Pinar; Akyuz, Gulseren; Yagci, Ilker; Giray, Esra

    2015-02-01

    The aim of the study was to investigate the effects of hypovitaminosis D on pain, quality of life (QoL) and nerve conduction studies (NCSs) in patients with chronic widespread pain (CWP). We randomly selected 83 female patients with CWP according to their vitamin D levels in this cross-sectional study. Patients were divided into two groups as sufficient vitamin D level (above 20 ng/ml) and deficient vitamin D level (below 20 ng/ml, hypovitaminosis D). Various pain scales and Nottingham Health Profile (NHP) were used. NCSs were also done. In patients with hypovitaminosis D, there were significantly higher pain scores for all scales (p value range 0.002-0.027). The subscale and total NHP scores were significantly higher in hypovitaminosis D group (p = 0.048-0.001) except social isolation subscale (p = 0.553). Vitamin D levels were in negative correlation with right and left median and/or ulnar motor nerve amplitudes, left tibial motor amplitude. This study confirm that hypovitaminosis D is related with higher pain intensity and lower QoL scores in patients with CWP when compared with control group. Additionally, we identified for the first time that there were negative correlations between vitamin D levels and some findings of NCSs.

  7. Hypovitaminosis D in widespread pain: its effect on pain perception, quality of life and nerve conduction studies.

    PubMed

    Kuru, Pinar; Akyuz, Gulseren; Yagci, Ilker; Giray, Esra

    2015-02-01

    The aim of the study was to investigate the effects of hypovitaminosis D on pain, quality of life (QoL) and nerve conduction studies (NCSs) in patients with chronic widespread pain (CWP). We randomly selected 83 female patients with CWP according to their vitamin D levels in this cross-sectional study. Patients were divided into two groups as sufficient vitamin D level (above 20 ng/ml) and deficient vitamin D level (below 20 ng/ml, hypovitaminosis D). Various pain scales and Nottingham Health Profile (NHP) were used. NCSs were also done. In patients with hypovitaminosis D, there were significantly higher pain scores for all scales (p value range 0.002-0.027). The subscale and total NHP scores were significantly higher in hypovitaminosis D group (p = 0.048-0.001) except social isolation subscale (p = 0.553). Vitamin D levels were in negative correlation with right and left median and/or ulnar motor nerve amplitudes, left tibial motor amplitude. This study confirm that hypovitaminosis D is related with higher pain intensity and lower QoL scores in patients with CWP when compared with control group. Additionally, we identified for the first time that there were negative correlations between vitamin D levels and some findings of NCSs. PMID:25085713

  8. Effect of establishing pain committee on the pain assessment skills of paediatric nurses.

    PubMed

    Farahani, Pouran Varvani; Alhani, Fatemeh; Mohammadi, Eisa

    2014-10-01

    Successful pain management relies on pain assessment. The purpose of this study is to investigate the effect of establishing pain committee on pain assessment skills of paediatric nurses. We used a quasi-experimental design. The study was conducted in surgery, emergency and orthopaedic wards of two teaching hospitals selected through simple random sampling. The intervention consisted of establishing a pain committee, the steps of which included organizing (3 months), holding workshop (five sessions) and clinical training (1 week). We found that the scores in the intervention group were significantly higher than those in the control group. Therefore, establishing pain committee in the management level of nursing improves nurses' pain assessment skills.

  9. Apomorphine effect on pain threshold in Parkinson's disease: a clinical and positron emission tomography study.

    PubMed

    Dellapina, Estelle; Gerdelat-Mas, Angélique; Ory-Magne, Fabienne; Pourcel, Laure; Galitzky, Monique; Calvas, Fabienne; Simonetta-Moreau, Marion; Thalamas, Claire; Payoux, Pierre; Brefel-Courbon, Christine

    2011-01-01

    Patients with Parkinson's disease (PD) frequently experience pain that could be in part due to central modification of nociception. In this randomized controlled double blind study, we compared the effect of apomorphine versus placebo on pain thresholds and pain-induced cerebral activity in 25 patients with PD. Subjective pain threshold (using thermal stimulation, thermotest), objective pain threshold (nociceptive flexion reflex), and cerebral activity (H(2)(15)O PET) during noxious and innocuous stimulations were performed. Neither subjective nor objective pain thresholds nor pain activation profile were modified by apomorphine compared with placebo in 25 PD patients. Apomorphine has no effect on pain processing in PD. We suggest that other monoamine systems than dopaminergic system could be involved.

  10. Experimental Studies in Ice Nucleation

    NASA Astrophysics Data System (ADS)

    Wright, Timothy Peter

    Ice nuclei play a critical role in the formation of precipitation in mixed phase clouds. Modification of IN concentrations can lead to changes in cloud lifetimes and precipitation size. Presented in this study are experimental investigations into ice nuclei in an ongoing effort to reduce the uncertainties that ice nuclei have on cloud processes and climate. This research presents a new version of the cold stage drop freezing assay to investigate the time-dependence of heterogeneous nucleation. The temperature range for the instrument spans from the melting point of water to the homogeneous freezing limit of ˜-38 deg C. Temperature stability for the instrument allowed for experimental operation for up to four days while interrogating the same sample. Up to a one hundred fold increase in the number of analyzed drops was accomplished through an in-house written automated drop freezing detection software package. Combined instrument design improvements allow for the analysis of IN concentrations down to ˜10-8 ice nuclei per picoliter of sample water. A new variant of the multiple-component stochastic model for heterogeneous ice nucleation was used to investigate the time dependence of heterogeneous freezing processes. This was accomplished by analyzing how the changes in the cooling rate can impact the observed nucleation rate. The model employed four material-dependent parameters to accurately capture the observed freezing of water drops containing Arizona Test Dust. The parameters were then used to accurately predict the freezing behavior of the drops in time dependent experiments. The time dependence freezing of a wide range of materials was then investigated. These materials included the minerals montmorillonite and kaolinite, the biological proxy ice nuclei contained within the product Icemax, and flame soot generated from the incomplete combustion of ethylene gas. The time dependence for ice nuclei collected from rainwater samples was also investigated. The

  11. Self-reports of medication side effects and pain-related activity interference in patients with chronic pain: a longitudinal cohort study.

    PubMed

    Martel, Marc O; Finan, Patrick H; Dolman, Andrew J; Subramanian, Subu; Edwards, Robert R; Wasan, Ajay D; Jamison, Robert N

    2015-06-01

    The primary purpose of this study was to examine the association between self-reports of medication side effects and pain-related activity interference in patients with chronic pain. The potential moderators of the association between reports of side effects and pain-related activity interference were also examined. A total of 111 patients with chronic musculoskeletal pain were asked to provide, once a month for a period of 6 months, self-reports of medication use and the presence of any perceived side effects (eg, nausea, dizziness, headaches) associated with their medications. At each of these time points, patients were also asked to provide self-reports of pain intensity, negative affect, and pain-related activity interference. Multilevel modeling analyses revealed that month-to-month increases in perceived medication side effects were associated with heightened pain-related activity interference (P < 0.05). Importantly, multilevel models revealed that perceived medication side effects were associated with heightened pain-related activity interference even after controlling for the influence of patient demographics, pain intensity, and negative affect. This study provides preliminary evidence that reports of medication side effects are associated with heightened pain-related activity interference in patients with chronic pain beyond the influence of other pain-relevant variables. The implications of our findings for clinical practice and the management of patients with chronic pain conditions are discussed.

  12. Experimental Infrasound Studies in Nevada

    NASA Astrophysics Data System (ADS)

    Herrin, E. T.; Negraru, P. T.; Golden, P.; Williams, A.

    2009-12-01

    An experimental propagation study was carried out in Nevada in June 2009 on Julian days 173-177. During this field experiment we deployed 16 single channel digital infrasound recorders to monitor the munitions disposal activities near Hawthorne, NV. The sensors were deployed in a single line and placed approximately 12 km apart at distances ranging from 2 to 177 km. A four element semi-permanent infrasound array named FNIAR was installed approximately 154 km north of the detonation site in line with the individual temporary recorders. Tropospheric arrivals were observed during all days of the experiment, but during day 176 the observed arrivals had very large amplitudes. A large signal was observed at 58 km from the detonation site with amplitude as large as 4 Pascals, while at 94 km no signal was observed. At FNIAR the amplitude of the tropospheric arrival was 1 Pascal. During this day meteorological data acquired in the propagation path showed a strong jet stream to the north. On day 177 we were not able to identify tropospheric arrivals beyond 34 km, but at stations beyond 152 km we observed stratospheric arrivals. Continuous monitoring of these signals at FNIAR shows that stratospheric arrivals are the most numerous. In a two month period, from 06/15/2009 to 08/15/2009 there were 35 operational days at the Hawthorne disposal facility resulting in 212 explosions with known origin times. Based on the celerity values there were 115 explosions that have only stratospheric arrivals (celerities of 300-275 m/s), 72 explosions with both tropospheric (celerities above 330 m/s) and stratospheric arrivals, 20 explosions that were not detected and five explosions that have only tropospheric arrivals.

  13. Differential Diagnoses for Persistent Pain Following Root Canal Treatment: A Study in the National Dental PBRN

    PubMed Central

    Nixdorf, Donald R.; Law, Alan S.; John, Mike T.; Sobieh, Radwa M.; Kohli, Richie; Nguyen, Ruby H.N.

    2015-01-01

    Introduction Pain present 6 months following root canal treatment (RCT) may be either of odontogenic or nonodontogenic origin. This is importance because treatments and prognoses are different; therefore the aim of this study was to provide specific diagnoses of patients reporting pain 6 months after receiving initial orthograde RCT. Methods We enrolled patients from the Midwest region of an existing prospective observational study of pain after RCT. Pain at 6 months was defined as ≥1 day of pain and average pain intensity of at least 1/10 over the preceding month. An Endodontist and an Orofacial Pain practitioner independently performed clinical evaluations, which included periapical and cone-beam CT radiographs, to determine diagnoses. Results Thirty-eight out of the 354 eligible patients in the geographic area (11%) met the pain criteria, with 19 (50%) consenting to be clinically evaluated. As the sole reason for pain, 7 patients (37%) were given odontogenic diagnoses (4 involving the RCT tooth, 3 involving an adjacent tooth). Eight patients (42%) were given nonodontogenic pain diagnoses (7 from referred temporomandibular disorder (TMD) pain, 1 from persistent dentoalveolar pain disorder (PDAP)). Two patients (11%) had both odontogenic and nonodontogenic diagnoses, while 2 (11%) no longer fit the pain criteria at the time of the clinical evaluation. Conclusion Patients reporting “tooth” pain 6 months following RCT had a nonodontogenic pain diagnosis accounting for some of this pain, with TMD being the most frequent nonodonotgenic diagnosis. Dentists should have the necessary knowledge to differentiate between these diagnoses to adequately manage their patients. PMID:25732400

  14. PAIN CHARACTERISTICS OF TEMPOROMANDIBULAR DISORDER – A PILOT STUDY IN PATIENTS WITH CERVICAL SPINE DYSFUNCTION

    PubMed Central

    Pedroni, Cristiane Rodrigues; de Oliveira, Anamaria Siriani; Bérzin, Fausto

    2006-01-01

    Objective: The purpose of the present pilot study was to describe pain complaints of TMD patients and cervical spine dysfunction. Methods: Fourteen women with myogenous TMD, cervical motion limitation and rotation of at least one of the three first cervical vertebrae evidenced by radiographic examination participated in this study. The multidimensional pain evaluation was accomplished by a Brazilian version of the McGill Pain Questionnaire. Results: The results showed that the most painful body site mentioned was cervical spine, followed by scapular region and temporomandibular joint. More than half of the volunteers reported temporal pain pattern as rhythmic, periodic and, or still, intermittent. The majority of the patients classified the pain intensity assessed at the moment of the evaluation as mild to discomforting. Absolute agreement was not observed among volunteers regarding word dimensions used to describe their pain, although a great number of patients chose the descriptor related to tension as the better expression to describe their painful complaint. Conclusion: Pain characteristics of TMD patients with cervical spine dysfunction showed cervical spine as a common painful region reported and words related to affective and emotional dimensions of pain perception can be used by these patients to qualify their pain complain. PMID:19089063

  15. The lidocaine metabolite N-ethylglycine has antinociceptive effects in experimental inflammatory and neuropathic pain.

    PubMed

    Werdehausen, Robert; Mittnacht, Sebastian; Bee, Lucy A; Minett, Michael S; Armbruster, Anja; Bauer, Inge; Wood, John N; Hermanns, Henning; Eulenburg, Volker

    2015-09-01

    Glycine transporter 1 (GlyT1) plays a crucial role in regulating extracellular glycine concentrations and might thereby constitute a new drug target for the modulation of glycinergic inhibition in pain signaling. Consistent with this view, inhibition of GlyT1 has been found to induce antinociceptive effects in various animal pain models. We have shown previously that the lidocaine metabolite N-ethylglycine (EG) reduces GlyT1-dependent glycine uptake by functioning as an artificial substrate for this transporter. Here, we show that EG is specific for GlyT1 and that in rodent models of inflammatory and neuropathic pain, systemic treatment with EG results in an efficient amelioration of hyperalgesia and allodynia without affecting acute pain. There was no effect on motor coordination or the development of inflammatory edema. No adverse neurological effects were observed after repeated high-dose application of EG. EG concentrations both in blood and spinal fluid correlated with an increase of glycine concentration in spinal fluid. The time courses of the EG and glycine concentrations corresponded well with the antinociceptive effect. Additionally, we found that EG reduced the increase in neuronal firing of wide-dynamic-range neurons caused by inflammatory pain induction. These findings suggest that systemically applied lidocaine exerts antihyperalgesic effects through its metabolite EG in vivo, by enhancing spinal inhibition of pain processing through GlyT1 modulation and subsequent increase of glycine concentrations at glycinergic inhibitory synapses. EG and other substrates of GlyT1, therefore, may be a useful therapeutic agent in chronic pain states involving spinal disinhibition.

  16. The lidocaine metabolite N-ethylglycine has antinociceptive effects in experimental inflammatory and neuropathic pain

    PubMed Central

    Werdehausen, Robert; Mittnacht, Sebastian; Bee, Lucy A.; Minett, Michael S.; Armbruster, Anja; Bauer, Inge; Wood, John N.; Hermanns, Henning; Eulenburg, Volker

    2015-01-01

    Abstract Glycine transporter 1 (GlyT1) plays a crucial role in regulating extracellular glycine concentrations and might thereby constitute a new drug target for the modulation of glycinergic inhibition in pain signaling. Consistent with this view, inhibition of GlyT1 has been found to induce antinociceptive effects in various animal pain models. We have shown previously that the lidocaine metabolite N-ethylglycine (EG) reduces GlyT1-dependent glycine uptake by functioning as an artificial substrate for this transporter. Here, we show that EG is specific for GlyT1 and that in rodent models of inflammatory and neuropathic pain, systemic treatment with EG results in an efficient amelioration of hyperalgesia and allodynia without affecting acute pain. There was no effect on motor coordination or the development of inflammatory edema. No adverse neurological effects were observed after repeated high-dose application of EG. EG concentrations both in blood and spinal fluid correlated with an increase of glycine concentration in spinal fluid. The time courses of the EG and glycine concentrations corresponded well with the antinociceptive effect. Additionally, we found that EG reduced the increase in neuronal firing of wide-dynamic-range neurons caused by inflammatory pain induction. These findings suggest that systemically applied lidocaine exerts antihyperalgesic effects through its metabolite EG in vivo, by enhancing spinal inhibition of pain processing through GlyT1 modulation and subsequent increase of glycine concentrations at glycinergic inhibitory synapses. EG and other substrates of GlyT1, therefore, may be a useful therapeutic agent in chronic pain states involving spinal disinhibition. PMID:25932687

  17. Frequency, impact, and predictors of persistent pain after root canal treatment: a national dental PBRN study.

    PubMed

    Nixdorf, Donald R; Law, Alan S; Lindquist, Kimberly; Reams, Gregory J; Cole, Emery; Kanter, Keith; Nguyen, Ruby H N; Harris, D Robert

    2016-01-01

    Root canal treatment (RCT) is commonly performed surgery and persistent pain is known to occur, but little is known about how these patients are affected by this pain. Although biopsychosocial mechanisms are thought to be associated with the development of such pain, similar to persistent pain after surgery in other body sites, little is known about the baseline predictors for persistent pain. We assessed the frequency of persistent pain 6 months after RCT, measured the impact this pain had on patients, and determined predictive factors for persistent tooth pain in a multicenter prospective cohort study conducted within the National Dental Practice-Based Research Network. Of 708 patients enrolled, 651 (91.9%) provided follow-up data, with 65 (10.0%) meeting criteria for pain 6 months after RCT. On average, these patients reported their pain as mild to moderate in intensity, present for approximately 10 days in the preceding month, and minimally interfered with daily activities. After adjusting for the type of dental practitioner and patient age, gender, and household income, pain duration over the week before RCT significantly increased the risk of developing persistent pain (odds ratio = 1.19 per 1 day increase in pain duration, 95% confidence interval: 1.07-1.33), whereas optimism about the procedure reduced the risk (odds ratio = 0.39, 95% confidence interval: 0.22-0.67). Our data suggest that persistent pain 6 months after RCT is fairly common, but generally does not have a large impact on those experiencing it. Furthermore, patient age and gender did not predict persistent pain, whereas preoperative pain duration and the patient's expectation did. PMID:26335907

  18. Frequency, impact, and predictors of persistent pain after root canal treatment: a national dental PBRN study.

    PubMed

    Nixdorf, Donald R; Law, Alan S; Lindquist, Kimberly; Reams, Gregory J; Cole, Emery; Kanter, Keith; Nguyen, Ruby H N; Harris, D Robert

    2016-01-01

    Root canal treatment (RCT) is commonly performed surgery and persistent pain is known to occur, but little is known about how these patients are affected by this pain. Although biopsychosocial mechanisms are thought to be associated with the development of such pain, similar to persistent pain after surgery in other body sites, little is known about the baseline predictors for persistent pain. We assessed the frequency of persistent pain 6 months after RCT, measured the impact this pain had on patients, and determined predictive factors for persistent tooth pain in a multicenter prospective cohort study conducted within the National Dental Practice-Based Research Network. Of 708 patients enrolled, 651 (91.9%) provided follow-up data, with 65 (10.0%) meeting criteria for pain 6 months after RCT. On average, these patients reported their pain as mild to moderate in intensity, present for approximately 10 days in the preceding month, and minimally interfered with daily activities. After adjusting for the type of dental practitioner and patient age, gender, and household income, pain duration over the week before RCT significantly increased the risk of developing persistent pain (odds ratio = 1.19 per 1 day increase in pain duration, 95% confidence interval: 1.07-1.33), whereas optimism about the procedure reduced the risk (odds ratio = 0.39, 95% confidence interval: 0.22-0.67). Our data suggest that persistent pain 6 months after RCT is fairly common, but generally does not have a large impact on those experiencing it. Furthermore, patient age and gender did not predict persistent pain, whereas preoperative pain duration and the patient's expectation did.

  19. Management of Myofascial Pain of Upper Trapezius: A Three Group Comparison Study

    PubMed Central

    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

  20. A magnetoencephalography study of multi-modal processing of pain anticipation in primary sensory cortices.

    PubMed

    Gopalakrishnan, R; Burgess, R C; Plow, E B; Floden, D P; Machado, A G

    2015-09-24

    Pain anticipation plays a critical role in pain chronification and results in disability due to pain avoidance. It is important to understand how different sensory modalities (auditory, visual or tactile) may influence pain anticipation as different strategies could be applied to mitigate anticipatory phenomena and chronification. In this study, using a countdown paradigm, we evaluated with magnetoencephalography the neural networks associated with pain anticipation elicited by different sensory modalities in normal volunteers. When encountered with well-established cues that signaled pain, visual and somatosensory cortices engaged the pain neuromatrix areas early during the countdown process, whereas the auditory cortex displayed delayed processing. In addition, during pain anticipation, the visual cortex displayed independent processing capabilities after learning the contextual meaning of cues from associative and limbic areas. Interestingly, cross-modal activation was also evident and strong when visual and tactile cues signaled upcoming pain. Dorsolateral prefrontal cortex and mid-cingulate cortex showed significant activity during pain anticipation regardless of modality. Our results show pain anticipation is processed with great time efficiency by a highly specialized and hierarchical network. The highest degree of higher-order processing is modulated by context (pain) rather than content (modality) and rests within the associative limbic regions, corroborating their intrinsic role in chronification.

  1. A magnetoencephalography study of multi-modal processing of pain anticipation in primary sensory cortices.

    PubMed

    Gopalakrishnan, R; Burgess, R C; Plow, E B; Floden, D P; Machado, A G

    2015-09-24

    Pain anticipation plays a critical role in pain chronification and results in disability due to pain avoidance. It is important to understand how different sensory modalities (auditory, visual or tactile) may influence pain anticipation as different strategies could be applied to mitigate anticipatory phenomena and chronification. In this study, using a countdown paradigm, we evaluated with magnetoencephalography the neural networks associated with pain anticipation elicited by different sensory modalities in normal volunteers. When encountered with well-established cues that signaled pain, visual and somatosensory cortices engaged the pain neuromatrix areas early during the countdown process, whereas the auditory cortex displayed delayed processing. In addition, during pain anticipation, the visual cortex displayed independent processing capabilities after learning the contextual meaning of cues from associative and limbic areas. Interestingly, cross-modal activation was also evident and strong when visual and tactile cues signaled upcoming pain. Dorsolateral prefrontal cortex and mid-cingulate cortex showed significant activity during pain anticipation regardless of modality. Our results show pain anticipation is processed with great time efficiency by a highly specialized and hierarchical network. The highest degree of higher-order processing is modulated by context (pain) rather than content (modality) and rests within the associative limbic regions, corroborating their intrinsic role in chronification. PMID:26210576

  2. Root Canal Therapy Reduces Multiple Dimensions of Pain: A National Dental PBRN Study

    PubMed Central

    Law, Alan S.; Nixdorf, Donald R.; Rabinowitz, Ira; Reams, Gregory J.; Smith, James A.; Torres, Anibal V.; Harris, D. Robert

    2014-01-01

    Background Initial orthograde root canal therapy (RCT) is used to treat dentoalveolar pathosis. The affect RCT has on pain intensity has been frequently reported, but the affect on other dimensions of pain has not. Also, the lack of large prospective studies involving diverse groups of patients and practitioners that are not involved in data collection suggest that there are multiple opportunities for bias to be introduced when this data is systematically aggregated. Method This prospective observational study assessed pain intensity, duration, and its interference with daily activities among RCT patients. Sixty-two practitioners (46 general dentists, 16 endodontists) in the National Dental Practice-Based Research Network enrolled patients requiring RCT. Patient reported data were collected before, immediately following, and one week after treatment using the Graded Chronic Pain Scale. Results Enrollment of 708 patients was completed over 6 months with 655 patients (93%) providing one-week follow-up data. Prior to treatment, patients reported a mean (±standard deviation) worst pain intensity of 5.3±3.8 (0-10 scale), 50% had “severe” pain (≥7), and mean days in pain and days pain interfered with activities were 3.6±2.7 and 0.5±1.2, respectively. Following treatment, patients reported a mean worst pain intensity of 3.0±3.2, 19% had “severe” pain, and mean days in pain and days with pain interference were 2.1±2.4 and 0.4±1.1, respectively. All changes were statistically significant (p<0.0001). Conclusions RCT is an effective treatment for patients experiencing pain, significantly reducing pain intensity, duration, and related interference. Further research is needed to reduce the proportion of patients reporting “severe” post-operative pain. PMID:25190605

  3. Sleep problems and pain: a longitudinal cohort study in emerging adults.

    PubMed

    Bonvanie, Irma J; Oldehinkel, Albertine J; Rosmalen, Judith G M; Janssens, Karin A M

    2016-04-01

    Sleep and pain are thought to be bidirectional related on a daily basis in adolescents with chronic pain complaints. In addition, sleep problems have been shown to predict the long-term onset of musculoskeletal pain in middle-aged adults. Yet, the long-term effects of sleep problems on pain duration and different types of pain severity in emerging adults (age: 18-25) are unknown. This study investigated the cross-sectional and longitudinal relationship between sleep problems and chronic pain, and musculoskeletal pain, headache, and abdominal pain severity in a general population of emerging adults. We studied whether these relationships were moderated by sex and whether symptoms of anxiety and depression, fatigue, or physical inactivity mediated these effects. Data of participants from the longitudinal Dutch TRacking Adolescents' Individual Lives Survey were used. Follow-up data were collected in 1753 participants who participated in the fourth (N = 1668, mean age: 19.0 years [SD = 0.6]) and/or fifth (N = 1501, mean age: 22.3 years [SD = 0.6]) assessment wave. Autoregressive cross-lagged models were used for analyses. Sleep problems were associated with chronic pain, musculoskeletal pain, headache and abdominal pain severity, and predicted chronic pain and an increase in musculoskeletal pain severity at 3 years of follow-up. This prospective effect was stronger in females than in males and was mediated by fatigue but not by symptoms of anxiety and depression or physical inactivity. Only abdominal pain had a small long-term effect on sleep problems. Our results suggest that sleep problems may be an additional target for treatment in female emerging adults with musculoskeletal pain complaints.

  4. An Exploratory Study into Objective and Reported Characteristics of Neuropathic Pain in Women with Chronic Pelvic Pain

    PubMed Central

    Whitaker, Lucy H. R.; Reid, Jen; Choa, Alex; McFee, Stuart; Seretny, Marta; Wilson, John; Elton, Rob A.; Vincent, Katy; Horne, Andrew W.

    2016-01-01

    Chronic pelvic pain (CPP) affects 5.7–26.6% women worldwide. 55% have no obvious pathology and 40% have associated endometriosis. Neuropathic pain (NeP) is pain arising as a consequence of a lesion/disease affecting the somatosensory system. The prevalence of NeP in women with CPP is not known. The diagnosis of NeP is challenging because there is no gold-standard assessment. Questionnaires have been used in the clinical setting to diagnose NeP in other chronic pain conditions and quantitative sensory testing (QST) has been used in a research setting to identify abnormal sensory function. We aimed to determine if women with chronic pelvic pain (CPP) have a neuropathic pain (NeP) component to their painful symptoms and how this is best assessed. We performed an exploratory prospective cohort study of 72 pre-menopausal women with a diagnosis of CPP. They underwent a clinician completed questionnaire (DN4) and completed the S-LANSS and PainDETECT™ questionnaires. Additionally QST testing was performed by a clinician. They also completed a patient acceptability questionnaire. Clinical features of NeP were identified by both questionnaires and QST. Of the women who were NeP positive, 56%, 35% and 26% were identified by the S-LANSS, DN4 and PainDETECT™ respectively. When NeP was identified by questionnaire, the associated laparoscopy findings were similar irrespective of which questionnaire was used. No subject had entirely unchanged QST parameters. There were distinct loss and gain subgroups, as well as mixed alteration in function, but this was not necessarily clinically significant in all patients. 80% of patients were confident that questionnaires could diagnose NeP, and 90% found them easy to complete. Early identification of NeP in women with CPP with a simple questionnaire could facilitate targeted therapy with neuromodulators, which are cheap, readily available, and have good safety profiles. This approach could prevent unnecessary or fertility

  5. Relationship between self-reported pain sensitivity and pain after total knee arthroplasty: a prospective study of 71 patients 8 weeks after a standardized fast-track program

    PubMed Central

    Valeberg, Berit T; Høvik, Lise H; Gjeilo, Kari H

    2016-01-01

    Background and purpose This was a prospective cohort study assessing data from 71 adult patients undergoing total knee arthroplasty (TKA) following a standardized fast-track program between January and July 2013. The objective was to examine the relationship between self-rated pain sensitivity, as measured by the Pain Sensitivity Questionnaire (PSQ), and postoperative pain after TKA. Methods The baseline questionnaires, PSQ and Brief Pain Inventory, were given to the patients for self-administration at the presurgical evaluation (1–2 weeks prior to surgery). The follow-up questionnaire, Brief Pain Inventory, was administered at the first follow-up, 8 weeks after surgery. Results A statistically significant association was found between average preoperative pain and average pain 8 weeks after surgery (P=0.001). The PSQ-minor was statistically significantly associated with average pain only for patients younger than 70 years (P=0.03). Interpretation This is the first study to examine the relationship between pain sensitivity measured by PSQ and postoperative pain in patients after TKA. We found that a lower score on the PSQ-minor was statistically significantly associated with patients’ pain 8 weeks after TKA surgery, but only for younger patients. Further research is needed to explore whether the PSQ could be a useful screening tool for patients’ pain sensitivity in clinical settings.

  6. Relationship between self-reported pain sensitivity and pain after total knee arthroplasty: a prospective study of 71 patients 8 weeks after a standardized fast-track program

    PubMed Central

    Valeberg, Berit T; Høvik, Lise H; Gjeilo, Kari H

    2016-01-01

    Background and purpose This was a prospective cohort study assessing data from 71 adult patients undergoing total knee arthroplasty (TKA) following a standardized fast-track program between January and July 2013. The objective was to examine the relationship between self-rated pain sensitivity, as measured by the Pain Sensitivity Questionnaire (PSQ), and postoperative pain after TKA. Methods The baseline questionnaires, PSQ and Brief Pain Inventory, were given to the patients for self-administration at the presurgical evaluation (1–2 weeks prior to surgery). The follow-up questionnaire, Brief Pain Inventory, was administered at the first follow-up, 8 weeks after surgery. Results A statistically significant association was found between average preoperative pain and average pain 8 weeks after surgery (P=0.001). The PSQ-minor was statistically significantly associated with average pain only for patients younger than 70 years (P=0.03). Interpretation This is the first study to examine the relationship between pain sensitivity measured by PSQ and postoperative pain in patients after TKA. We found that a lower score on the PSQ-minor was statistically significantly associated with patients’ pain 8 weeks after TKA surgery, but only for younger patients. Further research is needed to explore whether the PSQ could be a useful screening tool for patients’ pain sensitivity in clinical settings. PMID:27660489

  7. Evaluation of liposome-encapsulated butorphanol tartrate for alleviation of experimentally induced arthritic pain in green-cheeked conures (Pyrrhura molinae)

    PubMed Central

    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

  8. Citral: a monoterpene with prophylactic and therapeutic anti-nociceptive effects in experimental models of acute and chronic pain.

    PubMed

    Nishijima, Catarine M; Ganev, Ellen G; Mazzardo-Martins, Leidiane; Martins, Daniel F; Rocha, Lúcia R M; Santos, Adair R S; Hiruma-Lima, Clelia A

    2014-08-01

    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.

  9. An Actigraphy Study of Sleep and Pain in Midlife Women – The SWAN Sleep Study

    PubMed Central

    Kravitz, Howard M.; Zheng, Huiyong; Bromberger, Joyce T.; Buysse, Daniel J.; Owens, Jane; Hall, Martica H.

    2014-01-01

    Objective We examined whether women reporting nighttime pain would have more actigraphy-measured evidence for disturbed sleep and report feeling less rested compared to women without nighttime pain. Methods Up to 27 consecutive nights of actigraphy and sleep diary data were analyzed from each participant in this community-based study of 314 African-American (n=118), White (n=141), and Chinese (n=55) women, aged 48-58 years, who were pre-, peri- or post-menopausal and participating in the Study of Women's Health Across the Nation (SWAN) Sleep Study. Dependent variables were actigraphy-measured movement and fragmentation index, total sleep time, and sleep efficiency, and diary self-report of feeling rested after waking up. All outcomes were fit using linear mixed effect models to examine covariate-adjusted associations between the independent variable, nighttime pain severity, and sleep outcomes. Results Higher pain severity scores were associated with longer sleep duration but reduced sleep efficiency and feeling less rested. Women reporting nocturnal vasomotor symptoms had more sleep-related movement and sleep fragmentation, reduced sleep efficiency, and were less likely to feel rested after wakening, regardless of whether they reported pain. Conclusions Midlife women who report higher nighttime pain levels have more objective evidence for less efficient sleep, consistent with self-reported less restful sleep. Nocturnal vasomotor symptoms also can contribute to restlessness and wakefulness in midlife women. PMID:25706182

  10. Assessment of musculoskeletal pain sensitivity and temporal summation by cuff pressure algometry: a reliability study.

    PubMed

    Graven-Nielsen, Thomas; Vaegter, Henrik Bjarke; Finocchietti, Sara; Handberg, Gitte; Arendt-Nielsen, Lars

    2015-11-01

    Chronic musculoskeletal pain is linked with sensitization, and standardized methods for assessment are needed. This study investigated (1) the test-retest reliability of computer-controlled cuff-pressure algometry (pain thresholds and temporal pain summation) on the arm and leg and (2) conditioned pain modulation (CPM) assessed by cuff algometry. The influences of age and gender were evaluated. On 2 different days, cuff pain threshold (cPPT), cuff pain tolerance (cPTT), and temporal summation of pain (TSP) by visual analog scale scores to 10 repeated cuff stimulations at cPTT intensity, as well as pressure pain threshold with handheld pressure algometry, were assessed in 136 healthy subjects. In one session, cuff pain sensitivity was also assessed before and after cold pressor-induced CPM. Good-to-excellent intraclass correlations (0.60-0.90) were demonstrated for manual and cuff algometry, and no systematic bias between sessions was found for cPPT, cPTT, and TSP on the leg and for cPTT and TSP on the arm. Cuff pressure pain threshold and cPTT were higher in men compared with women (P < 0.05). Middle-aged subjects had higher pressure pain threshold, but lower cPPT and cPTT, compared with younger subjects (P < 0.05). Temporal summation of pain was increased in women compared with men (P < 0.05). Cuff algometry was sensitive to CPM demonstrated as increased cPPT and cPTT and reduced TSP (P < 0.05). Reliability and sensitivity of computer-controlled cuff algometry for pain assessment is comparable with manual pressure algometry and constitutes a user-independent method for assessment of pain. Difference in age-related pain sensitivity between manual and cuff algometry should be further investigated.

  11. The evolution of chronic pain among patients with musculoskeletal problems: a pilot study in primary care.

    PubMed

    Potter, R G; Jones, J M

    1992-11-01

    Little is known about the evolution of chronic pain in primary care. Forty five patients with a four week history of musculoskeletal pain were assessed and followed up over 26 weeks by a research nurse using a structured interview and formal assessment instruments. Patients aged 18 to 65 years were recruited on presentation at two semirural Cheshire general practices and subsequently interviewed on a domiciliary visit. Twenty patients (44%) continued to have pain at 26 weeks and these patients were considered to have chronic pain. Nineteen patients had no pain after 12 weeks and a further six had no pain after 26 weeks; these patients together formed the group with acute pain. Comparing the two groups at entry into the study (pain of four weeks' duration) demonstrated significantly higher visual analogue scale scores for intensity of pain (P < 0.01) and a higher incidence of depression (P < 0.01) in the group which subsequently developed chronic pain. In this group, the presence of depression at 12 weeks was associated with higher visual analogue scale scores (P < 0.05) but at 26 weeks scores were similar in depressed and non-depressed patients. The correlation between visual analogue scale score for intensity of pain and the use of passive coping strategies to cope with pain appeared more strongly positive with duration of pain (P < 0.05 at 26 weeks). It is suggested that high pain intensity scores, the presence of depression, and the increasing use of passive coping strategies may be identifiable associations with the development of chronic pain. Areas for further research are identified.

  12. Neurobiological Phenotypes of Familial Chronic Pain in Adolescence: A Pilot fMRI Study.

    PubMed

    Cservenka, Anita; Stein, Hannah; Wilson, Anna C; Nagel, Bonnie J

    2015-09-01

    Parental history of chronic pain has been associated with self-reported pain in adolescent offspring. This suggests that there may be neurobiological mechanisms associated with pain heritability. Because emotional circuitry is an important component of pain processing and may also influence cognition, we used functional magnetic resonance imaging to examine affective processing and cognitive control using an Emotional Go/NoGo task in youth with (FH + Pain, n = 8) and without (FH - Pain, n = 8) a parental history of chronic pain (mean age = 14.17 ± .34 years). FH + Pain youth had widespread reductions in brain activity within limbic and visual processing regions during processing of positively valenced emotional stimuli, as well as reduced frontoparietal response while processing negatively valenced emotional stimuli compared with their peers. In addition, during inhibition within a positive emotional context, FH + Pain youth had reduced cognitive control and salience-related brain activity. On the other hand, default mode-related brain response was increased during inhibitory control within a negative emotional context in these adolescents compared with their peers (P/α < .05). The current findings indicate differences in both emotional processing and cognitive control brain response in FH + Pain compared with FH - Pain youth, suggesting that both affective and executive functioning pathways may be important markers related to the intergenerational transmission of pain. Perspective: This is the first study to examine neurobiological markers of pain risk in adolescents with a family history of chronic pain. These findings may aid in the identification of neural phenotypes related to vulnerability for the onset of pain in at-risk youth. PMID:26117812

  13. Assessment of musculoskeletal pain sensitivity and temporal summation by cuff pressure algometry: a reliability study.

    PubMed

    Graven-Nielsen, Thomas; Vaegter, Henrik Bjarke; Finocchietti, Sara; Handberg, Gitte; Arendt-Nielsen, Lars

    2015-11-01

    Chronic musculoskeletal pain is linked with sensitization, and standardized methods for assessment are needed. This study investigated (1) the test-retest reliability of computer-controlled cuff-pressure algometry (pain thresholds and temporal pain summation) on the arm and leg and (2) conditioned pain modulation (CPM) assessed by cuff algometry. The influences of age and gender were evaluated. On 2 different days, cuff pain threshold (cPPT), cuff pain tolerance (cPTT), and temporal summation of pain (TSP) by visual analog scale scores to 10 repeated cuff stimulations at cPTT intensity, as well as pressure pain threshold with handheld pressure algometry, were assessed in 136 healthy subjects. In one session, cuff pain sensitivity was also assessed before and after cold pressor-induced CPM. Good-to-excellent intraclass correlations (0.60-0.90) were demonstrated for manual and cuff algometry, and no systematic bias between sessions was found for cPPT, cPTT, and TSP on the leg and for cPTT and TSP on the arm. Cuff pressure pain threshold and cPTT were higher in men compared with women (P < 0.05). Middle-aged subjects had higher pressure pain threshold, but lower cPPT and cPTT, compared with younger subjects (P < 0.05). Temporal summation of pain was increased in women compared with men (P < 0.05). Cuff algometry was sensitive to CPM demonstrated as increased cPPT and cPTT and reduced TSP (P < 0.05). Reliability and sensitivity of computer-controlled cuff algometry for pain assessment is comparable with manual pressure algometry and constitutes a user-independent method for assessment of pain. Difference in age-related pain sensitivity between manual and cuff algometry should be further investigated. PMID:26172551

  14. Chronic pain relief after the exposure of nitrous oxide during dental treatment: longitudinal retrospective study.

    PubMed

    Mattos Júnior, Francisco Moreira; Mattos, Rafael Villanova; Teixeira, Manoel Jacobsen; Siqueira, Silvia Regina Dowgan Tesseroli de; Siqueira, Jose Tadeu Tesseroli de

    2015-07-01

    The objective was to investigate the effect of nitrous/oxygen in chronic pain. Seventy-seven chronic pain patients referred to dental treatment with conscious sedation with nitrous oxide/oxygen had their records included in this research. Data were collected regarding the location and intensity of pain by the visual analogue scale before and after the treatment. Statistical analysis was performed comparing pre- and post-treatment findings. It was observed a remarkable decrease in the prevalence of pain in this sample (only 18 patients still had chronic pain, p < 0.001) and in its intensity (p < 0.001). Patients that needed fewer sessions received higher proportions of nitrous oxide/oxygen. Nitrous oxide may be a tool to be used in the treatment of chronic pain, and future prospective studies are necessary to understand the underlying mechanisms and the effect of nitrous oxide/oxygen in patients according to the pain diagnosis and other characteristics. PMID:26200051

  15. Quantifying the effectiveness of virtual reality pain management: a pilot study.

    PubMed

    Sulea, Camelia; Soomro, Ahmad; Wiederhold, Brenda K; Wiederhold, Mark D

    2014-01-01

    Sensory pathways, consisting of chains of neurons, which spread from the receptor organ to the cerebral cortex, are responsible for the perception of sensations (including pain). In this study, we set out to determine how effective virtual reality (VR) could be in distracting patients from pain experienced through thermoreceptors on the skin. Six healthy subjects were exposed to uncomfortable pain stimuli with and without VR distraction. Subjects reported a drop in pain while in the VR environment, and mean pain rating was significantly lower than the session with no VR distraction. These results indicate that VR distraction can diminish pain experienced by subjects, thus we conclude by eliciting future directions for quantifying effectiveness of VR as a pain management solution.

  16. Do psychological factors influence recovery from complex regional pain syndrome type 1? A prospective study.

    PubMed

    Bean, Debbie J; Johnson, Malcolm H; Heiss-Dunlop, Wolfgang; Lee, Arier C; Kydd, Robert R

    2015-11-01

    Previous studies have shown that the outcomes of complex regional pain syndrome (CRPS) vary significantly between patients, but few studies have identified prognostic indicators. The aim of this study was to determine whether psychological factors are associated with recovery from recently onset CRPS amongst patients followed prospectively for 1 year. Sixty-six patients with CRPS (type 1) were recruited within 12 weeks of symptom onset and assessed immediately and at 6 and 12 months, during which time they received treatment as usual. At each assessment, the following were measured: signs and symptoms of CRPS, pain, disability, depression, anxiety, stress, pain-related fear, pain catastrophising, laterality task performance, body perception disturbance, and perceived ownership of the limb. Mixed-effects models for repeated measures were conducted to identify baseline variables associated with CRPS severity, pain, and disability over the 12 months. Results showed that scores for all 3 outcome variables improved over the study period. Males and those with lower levels of baseline pain and disability experienced the lowest CRPS severity scores over 12 months. Those with lower baseline anxiety and disability had the lowest pain intensity over the study period, and those with lower baseline pain and pain-related fear experienced the least disability over the 12 months. This suggests that anxiety, pain-related fear, and disability are associated with poorer outcomes in CRPS and could be considered as target variables for early treatment. The findings support the theory that CRPS represents an aberrant protective response to perceived threat of tissue injury.

  17. Experimental studies on pump limiters

    NASA Astrophysics Data System (ADS)

    Mioduszewski, P.

    1982-12-01

    Pump limiters are mechanical devices for He-ash removal, fuel particle control, and possibly impurity control. Different designs have been suggested by various authors over the past decade. However, the magnetic divertor concepts seemed to be more promising, mainly because of their remote plasma-material interactions. All of the characteristics of magnetic divertors have been proven experimentally, but the overall performance and complexity cause concern about their application to tokamak reactors. Consequently, it is now time to explore the potential of mechanical particle control devices, i.e. pump limiters. Because of the high recycling at the limiter, it is sufficient to exhaust only a small fraction, about 1-10%, of the limiter particle flux to remove e.g. He at its rate of production. Pump limiter experiments have been conducted so far on Alcator, PDX, Macrotor, and ISX. Depending on the experimental design, a pressure build-up of between 1 mTorr and 50 mTorr has been reported. The closed configuration pump limiters provide high collection efficiencies, but have to accomodate high power fluxes at the leading edge. An open configuration, on the other hand, avoids leading edges but provides only fairly low collection efficiencies. The pump limiter development program now calls for a full pump limiter to be implemented in a major tokamak device. Presently, full-size pump limiter experiments on PDX, ISX, and TEXTOR are in preparation.

  18. Experimental studies on pump limiters

    SciTech Connect

    Mioduszewski, P.

    1982-01-01

    Pump limiters are mechanical devices for He-ash removal, fuel particle control, and possibly impurity control. Different designs have been suggested by various authors over the past decade. However, the magnetic divertor concepts seemed to be more promising, mainly because of their remote plasma-material interactions. All of the characteristics of magnetic divertors have been proven experimentally, but the overall performance and complexity cause concern about their application to tokamak reactors. Consequently, it is time now to explore the potential of mechanical particle control devices, i.e. pump limiters. Because of the high recycling at the limiter, it is sufficient to exhaust only a small fraction, about 1 to 10%, of the limiter particle flux to remove e.g. He at its rate of production. Pump limiter experiments have been conducted so far on Alcator, PDX, Macrotor, and ISX. Depending on the experimental design, a pressure build-up of between 1 mTorr and 50 mTorr has been reported.

  19. Pattern and quality of care of cancer pain management. Results from the Cancer Pain Outcome Research Study Group

    PubMed Central

    Apolone, G; Corli, O; Caraceni, A; Negri, E; Deandrea, S; Montanari, M; Greco, M T

    2009-01-01

    Most patients with advanced or metastatic cancer experience pain and despite several guidelines, undertreatment is well documented. A multicenter, open-label, prospective, non-randomised study was launched in Italy in 2006 to evaluate the epidemiology, patterns and quality of pain care of cancer patients. To assess the adequacy of analgesic care, we used a standardised measure, the pain management index (PMI), that compares the most potent analgesic prescribed for a patient with the reported level of the worst pain of that patient together with a selected list of clinical indicators. A total of 110 centres recruited 1801 valid cases. 61% of cases were received a WHO-level III opioid; 25.3% were classified as potentially undertreated, with wide variation (9.8–55.3%) according to the variables describing patients, centres and pattern of care. After adjustment with a multivariable logistic regression model, type of recruiting centre, receiving adjuvant therapy or not and type of patient recruited (new or already on follow-up) had a significant association with undertreatment. Non-compliance with the predefined set of clinical indicators was generally high, ranging from 41 to 76%. Despite intrinsic limitations of the PMI that may be considered as an indicator of the poor quality of cancer pain care, results suggest that the recourse to WHO third-level drugs still seems delayed in a substantial percentage of patients. This delay is probably related to several factors affecting practice in participating centres and suggests that the quality of cancer pain management in Italy deserves specific attention and interventions aimed at improving patients' outcomes. PMID:19401688

  20. Combined neuromodulatory interventions in acute experimental pain: assessment of melatonin and non-invasive brain stimulation

    PubMed Central

    da Silva, Nádia Regina Jardim; Laste, Gabriela; Deitos, Alícia; Stefani, Luciana Cadore; Cambraia-Canto, Gustavo; Torres, Iraci L. S.; Brunoni, Andre R.; Fregni, Felipe; Caumo, Wolnei

    2015-01-01

    Transcranial direct current stimulation (tDCS) and melatonin can effectively treat pain. Given their potentially complementary mechanisms of action, their combination could have a synergistic effect. Thus, we tested the hypothesis that compared to the control condition and melatonin alone, tDCS combined with melatonin would have a greater effect on pain modulatory effect, as assessed by quantitative sensory testing (QST) and by the pain level during the Conditioned Pain Modulation (CPM)-task. Furthermore, the combined treatment would have a greater cortical excitability effect as indicated by the transcranial magnetic stimulation (TMS) and on the serum BDNF level. Healthy males (n = 20), (aged 18–40 years), in a blinded, placebo-controlled, crossover, clinical trial, were randomized into three groups: sublingual melatonin (0.25 mg/kg) + a-tDCS, melatonin (0.25 mg/kg) + sham-(s)-tDCS, or sublingual placebo+sham-(s)-tDCS. Anodal stimulation (2 mA, 20 min) was applied over the primary motor cortex. There was a significant difference in the heat pain threshold (°C) for melatonin+a-tDCS vs. placebo+s-tDCS (mean difference: 4.86, 95% confidence interval [CI]: 0.9 to 8.63) and melatonin+s-tDCS vs. placebo+s-tDCS (mean: 5.16, 95% CI: 0.84 to 8.36). There was no difference between melatonin+s-tDCS and melatonin+a-tDCS (mean difference: 0.29, 95% CI: −3.72 to 4.23). The mean change from the baseline on amplitude of motor evocate potential (MEP) was significantly higher in the melatonin+a-tDCS (−19.96% ± 5.2) compared with melatonin+s-tDCS group (−1.36% ± 5.35) and with placebo+s-tDCS group (3.61% ± 10.48), respectively (p < 0.05 for both comparisons). While melatonin alone or combined with a-tDCS did not significantly affect CPM task result, and serum BDNF level. The melatonin effectively reduced pain; however, its association with a-tDCS did not present an additional modulatory effect on acute induced pain. PMID:25873871

  1. Neural Correlates of Empathy with Pain Show Habituation Effects. An fMRI Study

    PubMed Central

    Preis, Mira A.; Kröner-Herwig, Birgit; Schmidt-Samoa, Carsten; Dechent, Peter; Barke, Antonia

    2015-01-01

    Background Neuroimaging studies have demonstrated that the actual experience of pain and the perception of another person in pain share common neural substrates, including the bilateral anterior insular cortex and the anterior midcingulate cortex. As many fMRI studies include the exposure of participants to repeated, similar stimuli, we examined whether empathic neural responses were affected by habituation and whether the participants' prior pain experience influenced these habituation effects. Method In 128 trials (four runs), 62 participants (31 women, 23.0 ± 4.2 years) were shown pictures of hands exposed to painful pressure (pain pictures) and unexposed (neutral pictures). After each trial, the participants rated the pain of the model. Prior to the experiment, participants were either exposed to the same pain stimulus (pain exposure group) or not (touch exposure group). In order to assess possible habituation effects, linear changes in the strength of the BOLD response to the pain pictures (relative to the neutral pictures) and in the ratings of the model’s pain were evaluated across the four runs. Results Although the ratings of the model’s pain remained constant over time, we found neural habituation in the bilateral anterior/midinsular cortex, the posterior midcingulate extending to dorsal posterior cingulate cortex, the supplementary motor area, the cerebellum, the right inferior parietal lobule, and the left superior frontal gyrus, stretching to the pregenual anterior cingulate cortex. The participant’s prior pain experience did neither affect their ratings of the model’s pain nor their maintenance of BOLD activity in areas associated with empathy. Interestingly, participants with high trait personal distress and fantasy tended to show less habituation in the anterior insula. Conclusion Neural structures showed a decrease of the BOLD signal, indicating habituation over the course of 45 minutes. This can be interpreted as a neuronal mechanism

  2. Patellar maltracking is prevalent among patellofemoral pain subjects with patella alta: an upright, weightbearing MRI study

    PubMed Central

    Pal, Saikat; Besier, Thor F.; Beaupre, Gary S.; Fredericson, Michael; Delp, Scott L.; Gold, Garry E.

    2012-01-01

    The purpose of this study is to determine if patellar maltracking is more prevalent among patellofemoral (PF) pain subjects with patella alta compared to subjects with normal patella height. We imaged 37 PF pain and 15 pain free subjects in an open-configuration magnetic resonance imaging scanner while they stood in a weightbearing posture. We measured patella height using the Caton-Deschamps, Blackburne-Peel, Insall-Salvati, Modified Insall-Salvati, and Patellotrochlear indices, and classified the subjects into patella alta and normal patella height groups. We measured patella tilt and bisect offset from oblique-axial plane images, and classified the subjects into maltracking and normal tracking groups. Patellar maltracking was more prevalent among PF pain subjects with patella alta compared to PF pain subjects with normal patella height (two-tailed Fisher’s exact test, p < 0.050). Using the Caton-Deschamps index, 67% (8/12) of PF pain subjects with patella alta were maltrackers, whereas only 16% (4/25) of PF pain subjects with normal patella height were maltrackers. Patellofemoral pain subjects classified as maltrackers displayed a greater patella height compared to the pain free and PF pain subjects classified as normal trackers (two-tailed unpaired t-tests with Bonferroni correction, p < 0.017). This study adds to our understanding of PF pain in two ways - 1) we demonstrate that patellar maltracking is more prevalent in PF pain subjects with patella alta compared to subjects with normal patella height; and 2) we show greater patella height in PF pain subjects compared to pain free subjects using four indices commonly used in clinics. PMID:23165335

  3. Teachers’ experiences of adolescents’ pain in everyday life: a qualitative study

    PubMed Central

    Rohde, Gudrun; Westergren, Thomas; Haraldstad, Kristin; Johannessen, Berit; Høie, Magnhild; Helseth, Sølvi; Fegran, Liv; Slettebø, Åshild

    2015-01-01

    Objectives More adolescents report pain now than previously. In Norway, episodic pain problems have been reported by 60% of children and adolescents aged 8–18 years, with 21% reporting duration of pain of more than 3 months. Since adolescents spend much time at school, the attitude and behaviour of teachers play important roles regarding the experience of pain felt by adolescents in everyday life. Yet research on how teachers perceive the pain experienced by adolescents in a school setting is limited. We therefore seek to gain insight to teachers’ classroom experiences with (1) adolescent's self-reported pain symptoms; (2) adolescents management of their pain and (3) how to help adolescents manage their pain. Setting Teachers in 5 junior high schools in Norway representing municipalities in 3 rural areas and 2 cities. Research design A qualitative study with an explorative design comprising 5 focus group interviews. Each group consisted of 3–8 junior high school teachers. A semistructured interview guide was used to cover the issues. The transcribed text was analysed with qualitative content analysis. Participants 22 teachers participated (5 men, 17 women; age range 29–62 years) with teaching experience ranging from 3 to nearly 40 years. Results The main theme describing the experience of teachers with adolescents’ pain in everyday life is that pain and management of pain is a social, physical and psychological interwoven phenomenon. Through empirical analyses, 3 subcategories emerged: (1) everyday pain—expressing strenuous life; (2) managing pain—escaping struggle and (3) strategies of teachers—support and normalisation. Conclusions Teachers have a biopsychosocial understanding and approach to pain experienced by adolescents. This understanding influences the role of teachers as significant others in the lives of adolescents with regard to pain and management of their pain in a school setting. PMID:26338838

  4. Escalation of aggression: experimental studies.

    PubMed

    Goldstein, J H; Davis, R W; Herman, D

    1975-01-01

    A finding commonly obtained in research using the Buss "aggression machine" is a main effect for trail blocks, indicating an escalation in shock intensity over trails. Theoretical explanations for this effect were tested in a modified verbal operant-conditioning situation. In Experiment 1, subjects could administer any of 10 levels of positive reinforcement to a "learner" for correct verbal responses or any of 10 levels of negative reinforcement to a learner for incorrect responses. Half of the subjects were required to begin with weak, half with strong, reinforcements. Results indicated that, regardless of condition, subjects gave more intense reinforcements as the learning trails progressed. Those who administered negative reinforcements devalued the learner relative to those who administered positive reinforcements. In Experiment 2, a role-playing procedure was used in which subjects administered either positive or negative reinforcements to a learner whose performance either did or did not improve over trials. Again, in all experimental groups, subjects administered increasingly intense reinforcements over trials. The results are interpreted as supporting a disinhibition theory of anti- and prosocial behavior.

  5. AN EXPERIMENTAL STUDY OF DIATHERMY

    PubMed Central

    Christie, Ronald V.; Ehrich, Wilhelm; Binger, Carl A. L.

    1928-01-01

    1. An experimental pneumonia with more or less lobar distribution has been produced in dogs by the method of intrabronchial insufflation of B. friedlænderi, Type B, and Pneumococcus, Type I. 2. Such dogs as showed evidences of a pulmonary lesion when photographed by x-ray were selected for lung temperature measurements. 3. Measurements of lung temperature were made by means of thermocouples before and during diathermy. 4. The thermocouples which recorded the temperature in the consolidated lobes showed in most instances a more rapid rate of heating during diathermy than those in the normal lobes. The final increase in temperature in the pathological lobes over the normal lobes amounted to slightly more than 1°C. 5. When local heating occurred during diathermy it was of the order of magnitude found in a lung in which the branch of the pulmonary artery supplying it had been clamped. 6. Histological examination of the lungs showed the pathological reaction to consist of intraalveolar exudate composed of polymorphonuclear leucocytes and desquamated alveolar epithelium. In some sections the exudate was sufficient to cause compression and emptying of the alveolar capillaries. 7. The local heating, we believe, depends upon this ischemic state of the smaller vessels. 8. Further evidence for an imparied circulation in the pneumonic lung is furnished by injection preparations in which the uninjected area corresponded exactly to the gross pathological lesion. PMID:19869441

  6. Subgroups of musculoskeletal pain patients and their psychobiological patterns – The LOGIN study protocol

    PubMed Central

    2012-01-01

    Background Pain conditions of the musculoskeletal system are very common and have tremendous socioeconomic impact. Despite its high prevalence, musculoskeletal pain remains poorly understood and predominantly non-specifically and insufficiently treated. The group of chronic musculoskeletal pain patients is supposed to be heterogeneous, due to a multitude of mechanisms involved in chronic pain. Psychological variables, psychophysiological processes, and neuroendocrine alterations are expected to be involved. Thus far, studies on musculoskeletal pain have predominantly focused on the general aspects of pain processing, thus neglecting the heterogeneity of patients with musculoskeletal pain. Consequently, there is a need for studies that comprise a multitude of mechanisms that are potentially involved in the chronicity and spread of pain. This need might foster research and facilitate a better pathophysiological understanding of the condition, thereby promoting the development of specific mechanism-based treatments for chronic pain. Therefore, the objectives of this study are as follows: 1) identify and describe subgroups of patients with musculoskeletal pain with regard to clinical manifestations (including mental co-morbidity) and 2) investigate whether distinct sensory profiles or 3) distinct plasma levels of pain-related parameters due to different underlying mechanisms can be distinguished in various subgroups of pain patients. Methods/Design We will examine a population-based chronic pain sample (n = 100), a clinical tertiary care sample (n = 100) and pain-free patients with depression or post-traumatic stress disorder and pain-free healthy controls (each n = 30, respectively). The samples will be pain localisation matched by sex and age to the population-based sample. Patients will undergo physical examination and thorough assessments of mental co-morbidity (including psychological trauma), perceptual and central sensitisation (quantitative sensory

  7. A burden of illness study for neuropathic pain in Europe

    PubMed Central

    Liedgens, Hiltrud; Obradovic, Marko; De Courcy, Jonathan; Holbrook, Timothy; Jakubanis, Rafal

    2016-01-01

    Purpose Neuropathic pain (NP) is often severe and represents a major humanistic and economic burden. This study aimed at providing insight on this burden across France, Germany, Italy, Spain, and the UK, considering direct and indirect costs, productivity loss, and humanistic impact on patients and their families. Methods Physician questionnaires provided data on patients presenting with NP covering demographics, sick leave and retirement, number of consultations, drug treatments, and surgical procedures. Patients provided further demographic and disease-related data and completed the Work Productivity and Activity Impairment (WPAI), the EuroQol 5-Dimension (EQ-5D), and the Brief Pain Inventory (BPI) questionnaires. All health-related direct unitary costs were collected from relevant country-specific sources and adjusted to 2012 prices (€) where necessary. A subgroup analysis of costs based on diabetic peripheral neuropathy (n=894), fibromyalgia (n=300), and low back pain (n=963) was performed. Findings About 413 physicians completed a total of 3,956 patient records forms. Total annual direct health-care costs per patient ranged from €1,939 (Italy) to €3,131 (Spain). Annual professional caregiver costs ranged from €393 (France) to €1,242 (UK), but this only represented a small proportion of total care because much care is provided by family or friends. Sick leave costs ranged from €5,492 (UK) to €7,098 (France), with 10%–32% patients prevented from working at some point by NP. Total cost (including direct and indirect costs) of NP per patient was €10,313 in France (69% of the total cost), €14,446 in Germany (78%), €9,305 in Italy (69%), €10,597 in Spain (67%), and €9,685 in the UK (57%). Indirect costs (ie, sick leave) constituted the majority of costs in all five countries: €7,098 in France, €11,232 in Germany, €6,382 in Italy, €7,066 in Spain, and €5,492 in the UK. In the subgroup analysis, total annual direct costs per patient

  8. [Ethic charter of the German Society for the Study of Pain (DGSS)].

    PubMed

    Reiter-Theil, S; Graf-Baumann, T; Kutzer, K; Müller-Busch, H C; Stutzki, R; Traue, H C; Willweber-Strumpf, A; Zimmermann, M; Zenz, M

    2008-04-01

    The German Society for the Study of Pain has formed an interdisciplinary committee to answer urgent ethical questions on the diagnosis and treatment of pain and to give an ethical orientation on the care of pain and palliative patients. The treatment of pain is a fundamental objective of medicine. Competent and adequate relief of pain in all stages of life is a basic characteristic of a humane medicine oriented to the quality and meaning of life for people. However, there are substantial deficits in all areas, especially in the knowledge of physicians and patients, in training and further education, diagnosis and therapy. Freedom from pain is a substantial element of quality of life. A central duty of all physicians is an adequate diagnosis and treatment of acute pain and thereby the prophylaxis of chronic pain. If pain persists over a longer period of time, it loses the warning function and becomes taken for granted. Alterations, disabilities and limitations of the physical, psychic and social levels are the consequences. For these patients an interdisciplinary approach is necessary by which various medical disciplines, psychologists and physiotherapists are involved and all collaborate on the diagnosis and therapy of pain. All patients have the right to sufficient and individually tailored treatment of pain. Special attention must be paid to vulnerable patient groups, such as newborns, children and adolescents, as well as aged and mentally retarded patients. For cancer patients pain relief of their tumor pain is totally in the forefront. Indications of "unbearable pain" must not lead to resignation or even be seen as an argument for legalization of "death on request". The nursing of terminally ill patients necessitates a special measure not only of clinical, but also ethical competence, communication and multiprofessional collaboration. The modern options for palliative care are real alternatives to demands for legalization of "death on request". Physician

  9. A retrospective study on persistent pain after childbirth in the Netherlands.

    PubMed

    Bijl, Rianne C; Freeman, Liv M; Weijenborg, Philomeen Tm; Middeldorp, Johanna M; Dahan, Albert; van Dorp, Eveline L A

    2016-01-01

    Reported prevalence rates of persistent postpartum pain (PPP) range from less than 1% to almost 20%. The aim of this study was to examine the prevalence of PPP in a Dutch cohort and to evaluate a possible causal role for specific risk factors on the development of chronic pain after childbirth. A questionnaire was sent to 960 postpartum women approximately 2 years after delivery. Primary outcome was pain that arose from childbirth at follow-up, and secondary outcomes included quality of life (QoL) and Hospital Anxiety and Depression Scale scores. Tested risk factors included mode of labor analgesia, history of negative effect, history of chronic pain, delivery route, parity, and ethnicity. A total of 495 (51.6%) women participated. At a mean time of 2.3 postpartum years, 7.3% of women reported any pain and 6.1% reported significant pain related to the delivery. Compared to spontaneous delivery, cesarean delivery provided protection against persistent pain (odds ratio, 0.12; 95% CI, 0.01-0.63, P<0.05). None of the other risk factors, including remifentanil use for labor pain, were of influence on the prevalence of persistent pain. Women with PPP experienced greater negative effects and had lower QoL scores compared to women without pain. In this cohort of Dutch patients, PPP is a serious problem with a great impact on the physical and mental health of women. PMID:26834496

  10. A retrospective study on persistent pain after childbirth in the Netherlands.

    PubMed

    Bijl, Rianne C; Freeman, Liv M; Weijenborg, Philomeen Tm; Middeldorp, Johanna M; Dahan, Albert; van Dorp, Eveline L A

    2016-01-01

    Reported prevalence rates of persistent postpartum pain (PPP) range from less than 1% to almost 20%. The aim of this study was to examine the prevalence of PPP in a Dutch cohort and to evaluate a possible causal role for specific risk factors on the development of chronic pain after childbirth. A questionnaire was sent to 960 postpartum women approximately 2 years after delivery. Primary outcome was pain that arose from childbirth at follow-up, and secondary outcomes included quality of life (QoL) and Hospital Anxiety and Depression Scale scores. Tested risk factors included mode of labor analgesia, history of negative effect, history of chronic pain, delivery route, parity, and ethnicity. A total of 495 (51.6%) women participated. At a mean time of 2.3 postpartum years, 7.3% of women reported any pain and 6.1% reported significant pain related to the delivery. Compared to spontaneous delivery, cesarean delivery provided protection against persistent pain (odds ratio, 0.12; 95% CI, 0.01-0.63, P<0.05). None of the other risk factors, including remifentanil use for labor pain, were of influence on the prevalence of persistent pain. Women with PPP experienced greater negative effects and had lower QoL scores compared to women without pain. In this cohort of Dutch patients, PPP is a serious problem with a great impact on the physical and mental health of women.

  11. A retrospective study on persistent pain after childbirth in the Netherlands

    PubMed Central

    Bijl, Rianne C; Freeman, Liv M; Weijenborg, Philomeen TM; Middeldorp, Johanna M; Dahan, Albert; van Dorp, Eveline LA

    2016-01-01

    Reported prevalence rates of persistent postpartum pain (PPP) range from less than 1% to almost 20%. The aim of this study was to examine the prevalence of PPP in a Dutch cohort and to evaluate a possible causal role for specific risk factors on the development of chronic pain after childbirth. A questionnaire was sent to 960 postpartum women approximately 2 years after delivery. Primary outcome was pain that arose from childbirth at follow-up, and secondary outcomes included quality of life (QoL) and Hospital Anxiety and Depression Scale scores. Tested risk factors included mode of labor analgesia, history of negative effect, history of chronic pain, delivery route, parity, and ethnicity. A total of 495 (51.6%) women participated. At a mean time of 2.3 postpartum years, 7.3% of women reported any pain and 6.1% reported significant pain related to the delivery. Compared to spontaneous delivery, cesarean delivery provided protection against persistent pain (odds ratio, 0.12; 95% CI, 0.01–0.63, P<0.05). None of the other risk factors, including remifentanil use for labor pain, were of influence on the prevalence of persistent pain. Women with PPP experienced greater negative effects and had lower QoL scores compared to women without pain. In this cohort of Dutch patients, PPP is a serious problem with a great impact on the physical and mental health of women. PMID:26834496

  12. Cultural responses to pain in UK children of primary school age: a mixed-methods study.

    PubMed

    Azize, Pary M; Endacott, Ruth; Cattani, Allegra; Humphreys, Ann

    2014-06-01

    Pain-measurement tools are often criticized for not addressing the influence of culture and ethnicity on pain. This study examined how children who speak English as a primary or additional language discuss pain. Two methods were used in six focus group interviews with 34 children aged 4-7 years: (i) use of drawings from the Pediatric Pain Inventory to capture the language used by children to describe pain; and (ii) observation of the children's placing of pain drawings on red/amber/green paper to denote perceived severity of pain. The findings demonstrated that children with English as an additional language used less elaborate language when talking about pain, but tended to talk about the pictures prior to deciding where they should be placed. For these children, there was a positive significant relationship between language, age, and length of stay in the UK. The children's placement of pain drawings varied according to language background, sex, and age. The findings emphasize the need for sufficient time to assess pain adequately in children who do not speak English as a first language.

  13. Blocking of TRPV-1 in the parodontium relieves orthodontic pain by inhibiting the expression of TRPV-1 in the trigeminal ganglion during experimental tooth movement in rats.

    PubMed

    Gao, Yunan; Liu, Yingfei; Zhu, Kun; Zhang, Zhichao; Qiao, Hu; Lu, Zhen; Zhong, Tianyu; Liu, Yong; Zhou, Hong

    2016-08-15

    Orthodontic pain has confused the orthodontics for a long time, and recent research demonstrated that transient receptor potential vanilloid type 1 (TRPV1) had crucial functions in transduction of painful stimuli. The present research investigated the analgesia effects of the blocking TRPV1 on orthodontic pain during experimental tooth movement. Under challenge with experimental tooth movement, the expression of TRPV1 in the parodontium was increased in a time-dependent and force-dependent manner. And treatment with selective TRPV1 antagonist AMG-9810 in the parodontium reduced the expression of TRPV1 in the trigeminal ganglion (TG) and decreased the secretion of IL-1β in the gingival crevicular fluid. Furthermore, AMG-9810 could relieve orthodontic pain arising from experimental tooth movement in rats. We suggest that TRPV1 both in the parodontium and trigeminal ganglion are involved in orthodontic pain, and TRPV1 in the parodontium influence on orthodontic pain through reducing the expression of TRPV1 in trigeminal ganglion. Our finding may help to develop strategies for relieving orthodontic pain after orthodontics. PMID:27267133

  14. Intrusive pain and worry about health in older men: the CHAMP study.

    PubMed

    Blyth, F M; Cumming, R G; Nicholas, M K; Creasey, H; Handelsman, D J; Le Couteur, D G; Naganathan, V; Sambrook, P N; Seibel, M J; Waite, L M

    2011-02-01

    The role of anxiety in pain is less well understood than the role of depression. Based on recent conceptual thinking about worry and pain, we explored the relationship between pain status and worry about health and anxiety in 1217 community-dwelling men aged 70 years or older who participated in the baseline phase of the Concord Health and Ageing in Men Project study, a large population-based epidemiological study of healthy ageing based in Sydney, Australia. We hypothesised that worry about health would be associated with having persistent pain, and that the association would be stronger in the presence of co-existing pain-related interference with activities (intrusive pain). Of men in the study, 12.5% had persistent and intrusive pain, 22.4% were worried about their health, and 6.3% had anxiety. We found a strong association between worry about health and pain that was both persistent and intrusive, and that remained after accounting for age, number of comorbidities, depression, self-rated health status, arthritis, and gait speed (adjusted odds ratio 2.9; 95% confidence interval 1.8-4.7), P<0.0001). The corresponding adjusted odds ratio for the association between anxiety and pain was 2.3 (95% confidence interval 1.0-4.8; P=0.0363). These findings suggest that at a population level, subthreshold anxiety and pain are strongly related, and worry about health occurs much more commonly than anxiety itself. To our knowledge, this is the first study to explore, specifically, the relationship between pain status and worry about health in older men. In older community-dwelling men, pain was robustly associated with worry about health, highlighting the potential importance of subthreshold anxiety-related psychological factors. PMID:21168971

  15. Pregnancy related back pain, is it related to aerobic fitness? A longitudinal cohort study

    PubMed Central

    2012-01-01

    Background Low back pain with onset during pregnancy is common and approximately one out of three women have disabling pain. The pathogenesis of the pain condition is uncertain and there is no information on the role of physical fitness. Whether poorer physical conditioning is a cause or effect of back pain is also disputed and information from prospective studies needed. Methods A cohort of pregnant women, recruited from maternal health care centers in central Sweden, were examined regarding estimated peak oxygen uptake by cycle ergometer test in early pregnancy, reported physical activity prior to pregnancy, basic characteristics, back pain during pregnancy and back pain postpartum. Results Back pain during the current pregnancy was reported by nearly 80% of the women. At the postpartum appointment this prevalence was 40%. No association was displayed between estimated peak oxygen uptake and incidence of back pain during and after pregnancy, adjusted for physical activity, back pain before present pregnancy, previous deliveries, age and weight. A significant inverse association was found between estimated peak oxygen uptake and back pain intensity during pregnancy and a direct association post partum, in a fully adjusted multiple linear regression analysis. Conclusions Estimated peak oxygen uptake and reported physical activity in early pregnancy displayed no influence on the onset of subsequent back pain during or after pregnancy, where the time sequence support the hypothesis that poorer physical deconditioning is not a cause but a consequence of the back pain condition. The mechanism for the attenuating effect of increased oxygen uptake on back pain intensity is uncertain. PMID:22510295

  16. Effect of Music Therapy on Pain and Anxiety Levels of Cancer Patients: A Pilot Study

    PubMed Central

    Krishnaswamy, Priyadharshini; Nair, Shoba

    2016-01-01

    Background: The pain associated with cancer is highly detrimental to the quality of life of the affected individuals. It also contributes to the anxiety of the patient. There is a need for a nonpharmacological approach in addition to the pharmacological therapy for the management of the pain for a more holistic improvement in the individual. With this study, we wish to achieve this through music. Objective: To assess the effect of music therapy on pain scores and anxiety levels of cancer patients with pain. Study Design: In this quantitative study, a comparative study was done on fourteen cancer patients admitted for pain relief under the Department of Pain and Palliative Medicine, of a tertiary care hospital, having moderate to severe pain (numerical pain rating scale [NRS] – of 4 to 10). Subjects and Methods: Convenience sampling was used. Patients were allocated to test group or control group nonrandomly. The test group patients were subjected to music therapy for 20 min while the control group patients were kept occupied by talking to them for 20 min. The NRS scale was used to assess the pre- and post-interventional pain scores and the Hamilton anxiety rating scale was used to assess the pre- and post-interventional anxiety scores in the two groups. Statistics: Student's t-test was used for comparing the pre- and post-interventional data. Two sample t-test was used to compare the data obtained from the control and study groups. Results: Statistically significant reduction seen in the pain scores in the test group after music therapy (P = 0.003). No statistically significant reduction seen in the pain score in the control group (P = 0.356). There was a statistically significant reduction in the postintervention pain scores in the test group compared to the control group (P = 0.034). The reduction in anxiety levels in both groups after intervention was not statistically significant. Conclusion: Music therapy was found to lower the pain score of a patient who

  17. Atypical chest pain in a rehabilitation setting: a case study

    PubMed Central

    Oliva, Joseph S

    2001-01-01

    This case represents an individual who develops chest pain in a rehabilitation setting. It provides a description of possible assessments and investigations to screen for cardiovascular health. A thorough history and investigation can present a challenge in determining a definite diagnosis. Chiropractors who encounter patients in a rehabilitation program that develop chest pain must address the cardiac versus non-cardiac nature of the condition.

  18. Efficacy of fentanyl transdermal patch in pain control after lower third molar surgery: A preliminary study

    PubMed Central

    Vasovic, Miroslav; Andric, Miroslav; Todorovic, Ljubomir; Kokovic, Vladimir

    2016-01-01

    Background Surgical removal of impacted lower third molars is a common oral surgical procedure, generally followed by moderate to severe postoperative pain. Transdermal drug delivery as a concept offers interesting possibilities for postoperative pain control. The aim of this study was to evaluate the efficacy of transdermal system with fentanyl in relieving pain following impacted lower third molar surgery. Material and Methods Seventeen patients with bilateral impacted lower third molars were included in this preliminary study. For postoperative pain control, patients randomly received a fentanyl patch plus placebo tablet after the first operation and regular (placebo) patch and an analgesic, after the second operation. Analgesia was evaluated during first 24 hours postoperatively according to patients’ reports about time of first pain appearance and additional analgesic consumption. Pain severity was rated using a 10 cm long visual analogue scale (VAS). Results Intensity of postoperative pain and postoperative analgesic consumption were significantly lower after the Fentanyl Transdermal System (FTS) was applied (p<0.05). Duration of postoperative analgesia was significantly higher with FTS when compared to control treatment (p<0.05). Conclusions Based on the results of this preliminary study, transdermal system with fentanyl significantly reduced postoperative pain after third molar surgery. Key words:Analgesia, fentanyl, transdermal administration, third molar surgery, acute pain, postoperative care. PMID:27475691

  19. Sustained relief of ongoing experimental neuropathic pain by a CRMP2 peptide aptamer with low abuse potential.

    PubMed

    Xie, Jennifer Y; Chew, Lindsey A; Yang, Xiaofang; Wang, Yuying; Qu, Chaoling; Wang, Yue; Federici, Lauren M; Fitz, Stephanie D; Ripsch, Matthew S; Due, Michael R; Moutal, Aubin; Khanna, May; White, Fletcher A; Vanderah, Todd W; Johnson, Philip L; Porreca, Frank; Khanna, Rajesh

    2016-09-01

    Uncoupling the protein-protein interaction between collapsin response mediator protein 2 (CRMP2) and N-type voltage-gated calcium channel (CaV2.2) with an allosteric CRMP2-derived peptide (CBD3) is antinociceptive in rodent models of inflammatory and neuropathic pain. We investigated the efficacy, duration of action, abuse potential, and neurobehavioral toxicity of an improved mutant CRMP2 peptide. A homopolyarginine (R9)-conjugated CBD3-A6K (R9-CBD3-A6K) peptide inhibited the CaV2.2-CRMP2 interaction in a concentration-dependent fashion and diminished surface expression of CaV2.2 and depolarization-evoked Ca influx in rat dorsal root ganglia neurons. In vitro studies demonstrated suppression of excitability of small-to-medium diameter dorsal root ganglion and inhibition of subtypes of voltage-gated Ca channels. Sprague-Dawley rats with tibial nerve injury had profound and long-lasting tactile allodynia and ongoing pain. Immediate administration of R9-CBD3-A6K produced enhanced dopamine release from the nucleus accumbens shell selectively in injured animals, consistent with relief of ongoing pain. R9-CBD3-A6K, when administered repeatedly into the central nervous system ventricles of naive rats, did not result in a positive conditioned place preference demonstrating a lack of abusive liability. Continuous subcutaneous infusion of R9-CBD3-A6K over a 24- to 72-hour period reversed tactile allodynia and ongoing pain, demonstrating a lack of tolerance over this time course. Importantly, continuous infusion of R9-CBD3-A6K did not affect motor activity, anxiety, depression, or memory and learning. Collectively, these results validate the potential therapeutic significance of targeting the CaV-CRMP2 axis for treatment of neuropathic pain. PMID:27537210

  20. Experimental study and evaluation of radioprotective drugs

    NASA Technical Reports Server (NTRS)

    Smith, D. E.; Thomson, J. F.

    1968-01-01

    Experimental study evaluates radioprotective drugs administered before exposure either orally or intravenously. Specifically studied are the sources of radiation, choice of radiation dose, choice of animals, administration of drugs, the toxicity of protective agents and types of protective drug.

  1. Medial tibial pain. A prospective study of its cause among military recruits.

    PubMed

    Milgrom, C; Giladi, M; Stein, M; Kashtan, H; Margulies, J; Chisin, R; Steinberg, R; Swissa, A; Aharonson, Z

    1986-12-01

    In a prospective study of 295 infantry recruits during 14 weeks of basic training, 41% had medial tibial pain. Routine scintigraphic evaluation in cases of medial tibial bone pain showed that 63% had abnormalities. A stress fracture was found in 46%. Only two patients had periostitis. None had ischemic medial compartment syndrome. Physical examination could not differentiate between cases with medial tibial bone pain secondary to stress fractures and those with scintigraphically normal tibias. When both pain and swelling were localized in the middle one-third of the tibia, the lesion most likely proved to be a stress fracture.

  2. Peer volunteers in an integrative pain management program for frail older adults with chronic pain: study protocol for a randomized controlled trial

    PubMed Central

    2014-01-01

    Background Chronic pain is common among the older population. A literature review on pain management program showed that exercise, yoga, massage therapy, Tai Chi, and music therapy could significantly reduce pain. In spite of the proven benefits of pain management programs, these intervention programs were effective only in the short term, and older adults would resume their old habits. It has been suggested that interventions comprising some type of social support have great potential to increase the participation of older adults. Therefore, we propose the inclusion of peer volunteers in an integrated pain management program to relieve pain among frail older adults. This study aims to explore the effectiveness of an integrated pain management program supplemented with peer volunteers in improving pain intensity, functional mobility, physical activity, loneliness levels, happiness levels, and the use of non-pharmacological pain-relieving methods among frail older adults with chronic pain. Methods/Design We intend to recruit 30 nursing home residents and 30 peer volunteers from the Institute of Active Ageing in Hong Kong in a group trial for an 8-week group-based integrated pain management program. There will be 16 sessions, with two 1-hour sessions each week. The primary outcome will be pain levels, while secondary outcomes will be assessed according to functional mobility, physical activity, loneliness levels, happiness levels, the use of non-pharmacological pain-relieving methods, and through a questionnaire for volunteers. Discussion In view of the high prevalence of chronic pain among older adults and its adverse impacts, it is important to provide older adults with tools to control their pain. We propose the use of peer volunteers to enhance the effects of an integrated pain management program. It is expected that pain can be reduced and improvements can be achieved among older adults in the areas of physical activity, functional mobility, loneliness levels

  3. Study protocol title: a prospective cohort study of low back pain

    PubMed Central

    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

  4. Case Study: The Use of Massage Therapy to Relieve Chronic Low-Back Pain

    PubMed Central

    Allen, Laura

    2016-01-01

    Objectives To study the effects of massage on chronic low-back pain in a patient with four different diagnoses: osteoarthritis, scoliosis, spinal stenosis, and degenerative disc disease. The patient’s goal was to cut down on the amount of pain medication he takes. Methods A 63-year-old man with chronic back pain received four massages across a twenty-day period. Progress was recorded using the Oswestry Low Back Pain Scale, as he self-reported on levels of pain and interference with his activities of daily living. Results Improvement was noted in 9 out of 10 measurements of self-reported pain and activities of daily living, with the only exception being his ability to lift heavy objects, which remained unchanged. The most dramatic differences were improvements in his ability to walk, and in the changing degrees of pain. The client also self-reported being able to decrease his pain medication and the ability to ride his bicycle for the first time in years. Conclusions Massage therapy is a promising treatment for chronic low-back pain for patients who may have multiple pathologies, any one of which could be responsible for the condition. Further study is encouraged to determine the efficacy of massage therapy as a readily accessible, lower-cost alternative to more invasive therapies and as an adjunct to regular medical care, when appropriate. PMID:27648110

  5. Pain intensity rating training: results from an exploratory study of the ACTTION PROTECCT system.

    PubMed

    Smith, Shannon M; Amtmann, Dagmar; Askew, Robert L; Gewandter, Jennifer S; Hunsinger, Matthew; Jensen, Mark P; McDermott, Michael P; Patel, Kushang V; Williams, Mark; Bacci, Elizabeth D; Burke, Laurie B; Chambers, Christine T; Cooper, Stephen A; Cowan, Penney; Desjardins, Paul; Etropolski, Mila; Farrar, John T; Gilron, Ian; Huang, I-zu; Katz, Mitchell; Kerns, Robert D; Kopecky, Ernest A; Rappaport, Bob A; Resnick, Malca; Strand, Vibeke; Vanhove, Geertrui F; Veasley, Christin; Versavel, Mark; Wasan, Ajay D; Turk, Dennis C; Dworkin, Robert H

    2016-05-01

    Clinical trial participants often require additional instruction to prevent idiosyncratic interpretations regarding completion of patient-reported outcomes. The Analgesic, Anesthetic, and Addiction Clinical Trial Translations, Innovations, Opportunities, and Networks (ACTTION) public-private partnership developed a training system with specific, standardized guidance regarding daily average pain intensity ratings. A 3-week exploratory study among participants with low-back pain, osteoarthritis of the knee or hip, and painful diabetic peripheral neuropathy was conducted, randomly assigning participants to 1 of 3 groups: training with human pain assessment (T+); training with automated pain assessment (T); or no training with automated pain assessment (C). Although most measures of validity and reliability did not reveal significant differences between groups, some benefit was observed in discriminant validity, amount of missing data, and ranking order of least, worst, and average pain intensity ratings for participants in Group T+ compared with the other groups. Prediction of greater reliability in average pain intensity ratings in Group T+ compared with the other groups was not supported, which might indicate that training produces ratings that reflect the reality of temporal pain fluctuations. Results of this novel study suggest the need to test the training system in a prospective analgesic treatment trial. PMID:27058680

  6. Pain intensity rating training: results from an exploratory study of the ACTTION PROTECCT system.

    PubMed

    Smith, Shannon M; Amtmann, Dagmar; Askew, Robert L; Gewandter, Jennifer S; Hunsinger, Matthew; Jensen, Mark P; McDermott, Michael P; Patel, Kushang V; Williams, Mark; Bacci, Elizabeth D; Burke, Laurie B; Chambers, Christine T; Cooper, Stephen A; Cowan, Penney; Desjardins, Paul; Etropolski, Mila; Farrar, John T; Gilron, Ian; Huang, I-zu; Katz, Mitchell; Kerns, Robert D; Kopecky, Ernest A; Rappaport, Bob A; Resnick, Malca; Strand, Vibeke; Vanhove, Geertrui F; Veasley, Christin; Versavel, Mark; Wasan, Ajay D; Turk, Dennis C; Dworkin, Robert H

    2016-05-01

    Clinical trial participants often require additional instruction to prevent idiosyncratic interpretations regarding completion of patient-reported outcomes. The Analgesic, Anesthetic, and Addiction Clinical Trial Translations, Innovations, Opportunities, and Networks (ACTTION) public-private partnership developed a training system with specific, standardized guidance regarding daily average pain intensity ratings. A 3-week exploratory study among participants with low-back pain, osteoarthritis of the knee or hip, and painful diabetic peripheral neuropathy was conducted, randomly assigning participants to 1 of 3 groups: training with human pain assessment (T+); training with automated pain assessment (T); or no training with automated pain assessment (C). Although most measures of validity and reliability did not reveal significant differences between groups, some benefit was observed in discriminant validity, amount of missing data, and ranking order of least, worst, and average pain intensity ratings for participants in Group T+ compared with the other groups. Prediction of greater reliability in average pain intensity ratings in Group T+ compared with the other groups was not supported, which might indicate that training produces ratings that reflect the reality of temporal pain fluctuations. Results of this novel study suggest the need to test the training system in a prospective analgesic treatment trial.

  7. Case Study: The Use of Massage Therapy to Relieve Chronic Low-Back Pain

    PubMed Central

    Allen, Laura

    2016-01-01

    Objectives To study the effects of massage on chronic low-back pain in a patient with four different diagnoses: osteoarthritis, scoliosis, spinal stenosis, and degenerative disc disease. The patient’s goal was to cut down on the amount of pain medication he takes. Methods A 63-year-old man with chronic back pain received four massages across a twenty-day period. Progress was recorded using the Oswestry Low Back Pain Scale, as he self-reported on levels of pain and interference with his activities of daily living. Results Improvement was noted in 9 out of 10 measurements of self-reported pain and activities of daily living, with the only exception being his ability to lift heavy objects, which remained unchanged. The most dramatic differences were improvements in his ability to walk, and in the changing degrees of pain. The client also self-reported being able to decrease his pain medication and the ability to ride his bicycle for the first time in years. Conclusions Massage therapy is a promising treatment for chronic low-back pain for patients who may have multiple pathologies, any one of which could be responsible for the condition. Further study is encouraged to determine the efficacy of massage therapy as a readily accessible, lower-cost alternative to more invasive therapies and as an adjunct to regular medical care, when appropriate.

  8. Correlates of foot pain severity in adults with hallux valgus: a cross-sectional study

    PubMed Central

    2014-01-01

    Background Hallux valgus (HV) is highly prevalent and associated with progressive first metatarsophalangeal joint subluxation and osteoarthritis. The link between structural HV deformity and foot pain is unclear. This study investigated possible explanatory factors surrounding foot pain in HV, including radiographic HV angle and signs of joint degeneration. Methods Participants were 60 adults (53 female) with HV aged 20 to 75 years. Participant demographics and a range of radiographic, clinical and functional measures were considered potential correlates of foot pain. Self-reported foot pain (visual analogue scales and a dichotomous definition) was considered the dependent variable. Multivariate modelling was used to determine which characteristics and measures explained pain, with univariate analyses first used to screen potential variables. Results Approximately 20 to 30% of the variance in foot pain associated with HV could be explained by patient characteristics such as poorer general health status, lower educational attainment and increased occupational physical activity levels, in combination with some dynamic physical characteristics such as hallux plantarflexion weakness and reduced force-time integral under the second metatarsal during gait. Neither increasing lateral deviation of the hallux (HV angle) nor presence of first metatarsophalangeal joint osteoarthritis was associated with foot pain. Conclusions This study shows that passive structural factors, including HV angle, do not appear to be significant correlates of foot pain intensity in HV. Our data demonstrate the importance of considering patient characteristics such as general health and physical activity levels when assessing foot pain associated with HV. PMID:25028598

  9. Animal models of pancreatitis: can it be translated to human pain study?

    PubMed

    Zhao, Jing-Bo; Liao, Dong-Hua; Nissen, Thomas Dahl

    2013-11-14

    Chronic pancreatitis affects many individuals around the world, and the study of the underlying mechanisms leading to better treatment possibilities are important tasks. Therefore, animal models are needed to illustrate the basic study of pancreatitis. Recently, animal models of acute and chronic pancreatitis have been thoroughly reviewed, but few reviews address the important aspect on the translation of animal studies to human studies. It is well known that pancreatitis is associated with epigastric pain, but the understanding regarding to mechanisms and appropriate treatment of this pain is still unclear. Using animal models to study pancreatitis associated visceral pain is difficult, however, these types of models are a unique way to reveal the mechanisms behind pancreatitis associated visceral pain. In this review, the animal models of acute, chronic and un-common pancreatitis are briefly outlined and animal models related to pancreatitis associated visceral pain are also addressed.

  10. Acute low back pain is marked by variability: An internet-based pilot study

    PubMed Central

    2011-01-01

    Background Pain variability in acute LBP has received limited study. The objectives of this pilot study were to characterize fluctuations in pain during acute LBP, to determine whether self-reported 'flares' of pain represent discrete periods of increased pain intensity, and to examine whether the frequency of flares was associated with back-related disability outcomes. Methods We conducted a cohort study of acute LBP patients utilizing frequent serial assessments and Internet-based data collection. Adults with acute LBP (lasting ≤3 months) completed questionnaires at the time of seeking care, and at both 3-day and 1-week intervals, for 6 weeks. Back pain was measured using a numerical pain rating scale (NPRS), and disability was measured using the Oswestry Disability Index (ODI). A pain flare was defined as 'a period of increased pain lasting at least 2 hours, when your pain intensity is distinctly worse than it has been recently'. We used mixed-effects linear regression to model longitudinal changes in pain intensity, and multivariate linear regression to model associations between flare frequency and disability outcomes. Results 42 of 47 participants (89%) reported pain flares, and the average number of discrete flare periods per patient was 3.5 over 6 weeks of follow-up. More than half of flares were less than 4 hours in duration, and about 75% of flares were less than one day in duration. A model with a quadratic trend for time best characterized improvements in pain. Pain decreased rapidly during the first 14 days after seeking care, and leveled off after about 28 days. Patients who reported a pain flare experienced an almost 3-point greater current NPRS than those not reporting a flare (mean difference [SD] 2.70 [0.11]; p < 0.0001). Higher flare frequency was independently associated with a higher final ODI score (ß [SE} 0.28 (0.08); p = 0.002). Conclusions Acute LBP is characterized by variability. Patients with acute LBP report multiple distinct flares

  11. Efficacy and Safety of Acupuncture for Acute Low Back Pain in Emergency Department: A Pilot Cohort Study

    PubMed Central

    Liu, Yen-Ting; Chiu, Chih-Wen; Chang, Chin-Fu; Lee, Tsung-Chieh; Chen, Chia-Yun; Chang, Shun-Chang; Lee, Chia-Ying; Lo, Lun-Chien

    2015-01-01

    Introduction. Low back pain (LBP) is one of the most common complaints in the emergency department (ED). There are several research articles providing evidence for acupuncture for treating chronic LBP but few about treating acute LBP. This study assessed the efficacy and safety of acupuncture for the treatment of acute LBP in the ED. Materials and methods. A clinical pilot cohort study was conducted. 60 participants, recruited in the ED, were divided into experimental and control groups with 1 dropout during the study. Life-threatening conditions or severe neurological defects were excluded. The experimental group (n = 45) received a series of fixed points of acupuncture. The control group (n = 14) received sham acupuncture by pasting seed-patches near acupoints. Back pain was measured using the visual analog scale (VAS) at three time points: baseline and immediately after and 3 days after intervention as the primary outcome. The secondary outcomes were heart rate variability (HRV) and adverse events. Results. The VAS demonstrated a significant decrease (P value <0.001) for the experimental group after 15 minutes of acupuncture. The variation in HRV showed no significant difference in either group. No adverse event was reported. Conclusion. Acupuncture might provide immediate effect in reducing the pain of acute LBP safely. PMID:26346626

  12. Efficacy and Safety of Acupuncture for Acute Low Back Pain in Emergency Department: A Pilot Cohort Study.

    PubMed

    Liu, Yen-Ting; Chiu, Chih-Wen; Chang, Chin-Fu; Lee, Tsung-Chieh; Chen, Chia-Yun; Chang, Shun-Chang; Lee, Chia-Ying; Lo, Lun-Chien

    2015-01-01

    Introduction. Low back pain (LBP) is one of the most common complaints in the emergency department (ED). There are several research articles providing evidence for acupuncture for treating chronic LBP but few about treating acute LBP. This study assessed the efficacy and safety of acupuncture for the treatment of acute LBP in the ED. Materials and methods. A clinical pilot cohort study was conducted. 60 participants, recruited in the ED, were divided into experimental and control groups with 1 dropout during the study. Life-threatening conditions or severe neurological defects were excluded. The experimental group (n = 45) received a series of fixed points of acupuncture. The control group (n = 14) received sham acupuncture by pasting seed-patches near acupoints. Back pain was measured using the visual analog scale (VAS) at three time points: baseline and immediately after and 3 days after intervention as the primary outcome. The secondary outcomes were heart rate variability (HRV) and adverse events. Results. The VAS demonstrated a significant decrease (P value <0.001) for the experimental group after 15 minutes of acupuncture. The variation in HRV showed no significant difference in either group. No adverse event was reported. Conclusion. Acupuncture might provide immediate effect in reducing the pain of acute LBP safely. PMID:26346626

  13. An epidemiological study of low back pain in professional drivers

    NASA Astrophysics Data System (ADS)

    Bovenzi, Massimo; Rui, Francesca; Negro, Corrado; D'Agostin, Flavia; Angotzi, Giuliano; Bianchi, Sandra; Bramanti, Lucia; Festa, GianLuca; Gatti, Silvana; Pinto, Iole; Rondina, Livia; Stacchini, Nicola

    2006-12-01

    The prevalence of low back pain (LBP) was investigated in 598 Italian professional drivers exposed to whole-body vibration (WBV) and ergonomic risk factors (drivers of earth moving machines, fork-lift truck drivers, truck drivers, bus drivers). The control group consisted of a small sample of 30 fire inspectors not exposed to WBV. Personal, occupational and health histories were collected by means of a structured questionnaire. Vibration measurements were performed on representative samples of the machines and vehicles used by the driver groups. From the vibration magnitudes and exposure durations, alternative measures of vibration dose were estimated for each subject. Daily vibration exposure, expressed in terms of 8-h energy-equivalent frequency-weighted acceleration, A(8), averaged 0.28-0.61 (range 0.10-1.18) m s -2 rms in the driver groups. Duration of exposure to WBV ranged between 1 and 41 years. The 7-day and 12-month prevalence of LBP was greater in the driver groups than in the controls. In the professional drivers, the occurrence of 12-month LBP, high intensity of LBP (Von Korff pain scale score ⩾5), and LBP disability (Roland & Morris disability scale score ⩾12) significantly increased with increasing cumulative vibration exposure. Even though several alternative measures of vibration exposure were associated with LBP outcomes, nevertheless a more regular trend of association with LBP was found for vibration dose expressed as ∑ a vit i (m s -2 h), in which the frequency-weighted acceleration, a v, and lifetime exposure duration, t, were given equal weight. In multivariate data analysis, individual characteristics (e.g. age, body mass index) and a physical load index (derived from combining manual materials handling and awkward postures) were significantly associated with LBP outcomes, while psychosocial work factors (e.g. job decision, job support) showed a marginal relation to LBP. This study tends to confirm that professional driving in industry

  14. A Prevalence and Management Study of Acute Pain in Children Attending Emergency Departments by Ambulance.

    PubMed

    Murphy, Adrian; McCoy, Siobhan; O'Reilly, Kay; Fogarty, Eoin; Dietz, Jason; Crispino, Gloria; Wakai, Abel; O'Sullivan, Ronan

    2016-01-01

    Pain is the most common symptom in the emergency setting and remains one of the most challenging problems for emergency care providers, particularly in the pediatric population. The primary objective of this study was to determine the prevalence of acute pain in children attending emergency departments (EDs) in Ireland by ambulance. In addition, this study sought to describe the prehospital and initial ED management of pain in this population, with specific reference to etiology of pain, frequency of pain assessment, pain severity, and pharmacological analgesic interventions. A prospective cross-sectional study was undertaken over a 12-month period of all pediatric patients transported by emergency ambulance to four tertiary referral hospitals in Ireland. All children (<16 years) who had pain as a symptom (regardless of cause) at any stage during the prehospital phase of care were included in this study. Over the study period, 6,371 children attended the four EDs by emergency ambulance, of which 2,635 (41.4%, 95% confidence interval 40.2-42.3%) had pain as a documented symptom on the ambulance patient care report (PCR) form. Overall 32% (n = 856) of children who complained of pain were subject to a formal pain assessment during the prehospital phase of care. Younger age, short transfer time to the ED, and emergency calls between midnight and 6 am were independently associated with decreased likelihood of having a documented assessment of pain intensity during the prehospital phase of care. Of the 2,635 children who had documented pain on the ambulance PCR, 26% (n = 689) received some form of analgesic agent prior to ED arrival. Upon ED arrival 54% (n = 1,422) of children had a documented pain assessment and some form of analgesic agent was administered to 50% (n = 1,324). Approximately 41% of children who attend EDs in Ireland by ambulance have pain documented as their primary symptom. This study suggests that the management of acute pain in children transferred by

  15. Solitary Painful Osseous Metastases: Correlation of Imaging Features with Pain Palliation after Radiofrequency Ablation—A Multicenter American College of Radiology Imaging Network Study

    PubMed Central

    Guenette, Jeffrey P.; Lopez, Michael J.; Kim, Eunhee

    2013-01-01

    Purpose: To identify the correlation of pre- and postablation imaging features with pain relief, pain intensity, and patient mood after radiofrequency (RF) ablation of solitary painful osseous metastases. Materials and Methods: This prospective, multicenter group trial was approved by each institutional review board. Participants were enrolled between November 1, 2001, and April 6, 2006. Written informed consent was obtained from all subjects, and patient confidentiality protocols were followed in compliance with HIPAA. Computed tomography (CT)-guided RF ablation and contrast material–enhanced 1-month follow-up CT and/or magnetic resonance imaging were performed in 49 subjects (24 men, 25 women; age range, 34–83 years) with a confirmed malignant solitary bone lesion of maximum dimension of 8 cm or smaller that was causing intractable pain. Pain intensity and patient mood were measured before and after RF ablation. Tumor imaging features were recorded. Unadjusted and adjusted linear mixed-effects models, with a random intercept for each subject, were used to model patient mood, pain relief, and pain intensity scores at three times after ablation as a function of each tumor characteristic. Results: Decreased postablation tumor pain correlated with preablation tumor volume (P = .02) and pathologic fracture (P = .01), while pain relief correlated with pathologic fracture (P = .03) and percentage of bone-tumor interface (BTI) ablated (P = .02). Conversely, presence of an irregular rim after ablation (P = .02) and rim thickness (P = .01) correlated with increased pain. There was no evidence in this study that RF ablation of larger tumor percentage or larger volume leads to better pain relief or decreased pain (P > .05). Conclusion: Existing pathologic fracture and smaller tumor size appear to be predictive parameters of success when selecting patients for palliative RF ablation of painful solitary osseous metastases. Successful palliation also appears to be related

  16. Patient Satisfaction with Spanish Pain Centers: Observational Study with More than 3,000 Patients.

    PubMed

    García García, Juan Antonio; Hernández-Puiggròs, Patricia; Tesedo Nieto, Javier; Acín Lázaro, María Pilar; Carrera González, Alfredo; Soler, Miguel José Arranz; Maldonado Vega, Sergio

    2016-01-01

    Chronic pain is a serious problem in Spain. This multicenter, epidemiological 3-month follow-up study investigates pain management efficacy in Spanish centers using patient satisfaction criteria. 3,414 eligible adult patients (65,6% female) with moderate to severe chronic pain from 146 pain centers were included. Patient satisfaction was assessed based onto question 18 of Spanish healthcare barometer-CSI. Pain evolution (Brief Pain Inventory-Short Form (BPI-SF) and visual analog scale (VAS)), quality of life/EuroQol-5, and pain control expectations fulfillment were also assessed. Mean age was 61.3 years. 64.4% of participating centers employed multidisciplinary pain management approach. After 3 months, mean patient satisfaction was 7.8 (1-10) on the CIS barometer. Medical staff received the highest scores, whereas waiting for tests, appointment request to appointment date time, and waiting times at the center the lowest. Mean pain decreased from 7.4 to 4.0; BPI-SF intensity decreased from 6.5 to 3.8; pain control expectations were met in 78.7% of patients; EuroQoL-5D utility index increased from 0.37 to 0.62, p < 0.001, and health status (VAS) from 40.6 to 61.9, p < 0.001. Chronic pain patients (90%) are satisfied with Spanish centers care; 80% had their pain control expectations met. Quality of life improved remarkably: 71% felt moderately to significantly better. However, waiting times need improvement. PMID:27516902

  17. Patient Satisfaction with Spanish Pain Centers: Observational Study with More than 3,000 Patients

    PubMed Central

    Hernández-Puiggròs, Patricia; Tesedo Nieto, Javier; Acín Lázaro, María Pilar; Carrera González, Alfredo; Soler, Miguel José Arranz; Maldonado Vega, Sergio

    2016-01-01

    Chronic pain is a serious problem in Spain. This multicenter, epidemiological 3-month follow-up study investigates pain management efficacy in Spanish centers using patient satisfaction criteria. 3,414 eligible adult patients (65,6% female) with moderate to severe chronic pain from 146 pain centers were included. Patient satisfaction was assessed based onto question 18 of Spanish healthcare barometer-CSI. Pain evolution (Brief Pain Inventory-Short Form (BPI-SF) and visual analog scale (VAS)), quality of life/EuroQol-5, and pain control expectations fulfillment were also assessed. Mean age was 61.3 years. 64.4% of participating centers employed multidisciplinary pain management approach. After 3 months, mean patient satisfaction was 7.8 (1–10) on the CIS barometer. Medical staff received the highest scores, whereas waiting for tests, appointment request to appointment date time, and waiting times at the center the lowest. Mean pain decreased from 7.4 to 4.0; BPI-SF intensity decreased from 6.5 to 3.8; pain control expectations were met in 78.7% of patients; EuroQoL-5D utility index increased from 0.37 to 0.62, p < 0.001, and health status (VAS) from 40.6 to 61.9, p < 0.001. Chronic pain patients (90%) are satisfied with Spanish centers care; 80% had their pain control expectations met. Quality of life improved remarkably: 71% felt moderately to significantly better. However, waiting times need improvement. PMID:27516902

  18. Is the pain-reducing effect of opioid medication reliable? A psychophysical study of morphine and pentazocine analgesia.

    PubMed

    King, Christopher D; Goodin, Burel; Glover, Toni L; Riley, Joseph L; Hou, Wei; Staud, Roland; Fillingim, Roger B

    2013-03-01

    A number of laboratory studies have confirmed the efficacy of opioid medication in reducing pain generated by a number of psychophysical modalities. However, one implicit assumption of clinical and experimental pain testing of analgesics is that the analgesic response is stable and will be comparable across repeated administrations. In the current study, the repeatability of opioid analgesia was assessed in a randomized, double-blinded study using 3 psychophysical pain modalities (e.g., thermal, pressure, and ischemic) over 4 medication sessions (2 with active drug, 2 with placebo). Psychophysical responses were evaluated before and after intravenous administration of either morphine (0.08mg/kg; n=52) or pentazocine (0.5mg/kg; n=49). To determine the ability of a drug to reduce pain, 4 analytic methods (i.e., absolute change, percent change, ratio, and residualized change scores) were calculated to generate separate analgesic index scores for each measure and drug condition. All analgesic index scores demonstrated a greater analgesic response compared to saline for both medications, but stability (i.e., test-retest correlations) of the opioid analgesic indices depended on the pain measurement. Ischemic pain outcomes were moderately stable across sessions for both opioid medications; however, heat and pressure analgesic index scores were moderately stable for only morphine and pentazocine, respectively. Finally, within stimulus modalities, analgesic index scores were highly correlated with each other, suggesting that the different methods for computing analgesic responses provided comparable results. These results suggest that analgesic measures are able to distinguish between active drugs. In addition, analgesic responses to morphine and pentazocine demonstrate at least moderate reliability.

  19. Baropodometry on women suffering from chronic pelvic pain - a cross-sectional study

    PubMed Central

    2011-01-01

    Background Previous studies have associated chronic pelvic pain with a stereotyped pattern of movement and posture, lack of normal body sensations, a characteristic pain distribution. We aimed at evaluating if these postural changes are detectable in baropodometry results in patients with chronic pelvic pain. Methods We performed a prospective study in a university hospital. We selected 32 patients suffering from chronic pelvic pain (study group) and 30 women without this pathology (regular gynecological work out - control group). Pain scores and baropodometric analysis were performed. Results As expected, study group presented higher pain scores than control group. Study and control groups presented similar averages for the maximum pressures to the left and right soles as well as soles supports in the forefeet and hind feet. Women suffering from chronic pelvic pain did not present differences in baropodometric analysis when compared to healthy controls. Conclusions This data demonstrates that postural abnormalities resulting from CPP could not be demonstrated by baropodometric evaluation. Other postural measures should be addressed to evaluate pelvic pain patients. PMID:22093947

  20. Cryoanalgesia for pain after herniorrhaphy.

    PubMed

    Khiroya, R C; Davenport, H T; Jones, J G

    1986-01-01

    The effect of freezing the ilioinguinal nerve on postoperative pain relief was examined in a double blind study in 36 patients undergoing herniorrhaphy, randomly allocated into two groups. Patients in the experimental group had their ilioinguinal nerves frozen during surgery and were compared with the patients in the control group who did not have cryoanalgesia. Pain relief was assessed over a 48-hour period in three ways, namely the linear analogue pain scale, peak expiratory flow rates and the amount of analgesic drugs required by patients in the two groups. We conclude that cryoanalgesia of the ilioinguinal nerve alone does not produce significant early post herniorrhaphy pain relief. PMID:3511766

  1. Pregabalin for Refractory Radicular Leg Pain due to Lumbar Spinal Stenosis: A Preliminary Prospective Study.

    PubMed

    Orita, Sumihisa; Yamashita, Masaomi; Eguchi, Yawara; Suzuki, Miyako; Inoue, Gen; Miyagi, Masayuki; Watanabe, Tomoko; Ozawa, Tomoyuki; Kamoda, Hiroto; Ishikawa, Tetsuhiro; Aoki, Yasuchika; Ito, Toshinori; Kubota, Go; Suzuki, Munetaka; Yamauchi, Kazuyo; Hanaoka, Eiji; Sakuma, Yoshihiro; Shimbo, Jun; Oikawa, Yasuhiro; Suzuki, Takane; Takahashi, Kazuhisa; Ohtori, Seiji

    2016-01-01

    We investigated the efficacy of pregabalin (PGB) for neuropathic leg pain in lumbar spinal stenosis (LSS) patients with disturbed activities of daily living (ADL)/quality of life (QOL) in a prospective observational study. Subjects were a total of 104 LSS patients with neuropathic pain (NeP) in leg and neurological intermittent claudication (IMC) refractory to nonsteroidal anti-inflammatory drugs (NSAIDs) for at least a month. NeP was identified using screening tool, Pain DETECT questionnaire. Visual analog scale (VAS) scores and responses to the Japanese Orthopaedic Association Back Pain Evaluation Questionnaire (JOABPEQ) were assessed before and 6 weeks after PGB treatment initiation. Changes in IMC distance and adverse events were also recorded. PGB significantly improved their VAS scores for pain and sleep quality (P < 0.001). With respect to JOABPEQ, significant improvements were observed with regard to the following dimensions: pain-related disorders (P < 0.01), lumbar spine dysfunction (P = 0.031), gait disturbance (P = 0.028), and psychological disorders (P = 0.014). The IMC distance showed an improvement tendency after PGB treatment, albeit with no significance (P = 0.063). Minor adverse events such as dizziness were observed. PGB can be effective for neuropathic leg pain refractory to NSAIDs in LSS patients, resulting in not only pain control but also improving lower back pain-related ADL/QOL scores. PMID:27445615

  2. Selective small molecule angiotensin II type 2 receptor antagonists for neuropathic pain: preclinical and clinical studies.

    PubMed

    Smith, Maree T; Anand, Praveen; Rice, Andrew S C

    2016-02-01

    Neuropathic pain affects up to 10% of the general population, but drug treatments recommended for the treatment of neuropathic pain are associated with modest efficacy and/or produce dose-limiting side effects. Hence, neuropathic pain is an unmet medical need. In the past 2 decades, research on the pathobiology of neuropathic pain has revealed many novel pain targets for use in analgesic drug discovery programs. However, these efforts have been largely unsuccessful as molecules that showed promising pain relief in rodent models of neuropathic pain generally failed to produce analgesia in early phase clinical trials in patients with neuropathic pain. One notable exception is the angiotensin II type 2 (AT2) receptor that has clinical validity on the basis of a successful double-blind, randomized, placebo-controlled, clinical trial of EMA401, a highly selective, orally active, peripherally restricted AT2 receptor antagonist in patients with postherpetic neuralgia. In this study, we review research to date on target validation, efficacy, and mode of action of small molecule AT2 receptor antagonists in rodent models of peripheral neuropathic pain and in cultured human sensory neurons, the preclinical pharmacokinetics of these compounds, and the outcome of the above clinical trial.

  3. Pregabalin for Refractory Radicular Leg Pain due to Lumbar Spinal Stenosis: A Preliminary Prospective Study

    PubMed Central

    Orita, Sumihisa; Yamashita, Masaomi; Eguchi, Yawara; Suzuki, Miyako; Inoue, Gen; Miyagi, Masayuki; Watanabe, Tomoko; Ozawa, Tomoyuki; Kamoda, Hiroto; Ishikawa, Tetsuhiro; Aoki, Yasuchika; Ito, Toshinori; Kubota, Go; Suzuki, Munetaka; Yamauchi, Kazuyo; Hanaoka, Eiji; Sakuma, Yoshihiro; Shimbo, Jun; Oikawa, Yasuhiro; Suzuki, Takane; Takahashi, Kazuhisa; Ohtori, Seiji

    2016-01-01

    We investigated the efficacy of pregabalin (PGB) for neuropathic leg pain in lumbar spinal stenosis (LSS) patients with disturbed activities of daily living (ADL)/quality of life (QOL) in a prospective observational study. Subjects were a total of 104 LSS patients with neuropathic pain (NeP) in leg and neurological intermittent claudication (IMC) refractory to nonsteroidal anti-inflammatory drugs (NSAIDs) for at least a month. NeP was identified using screening tool, Pain DETECT questionnaire. Visual analog scale (VAS) scores and responses to the Japanese Orthopaedic Association Back Pain Evaluation Questionnaire (JOABPEQ) were assessed before and 6 weeks after PGB treatment initiation. Changes in IMC distance and adverse events were also recorded. PGB significantly improved their VAS scores for pain and sleep quality (P < 0.001). With respect to JOABPEQ, significant improvements were observed with regard to the following dimensions: pain-related disorders (P < 0.01), lumbar spine dysfunction (P = 0.031), gait disturbance (P = 0.028), and psychological disorders (P = 0.014). The IMC distance showed an improvement tendency after PGB treatment, albeit with no significance (P = 0.063). Minor adverse events such as dizziness were observed. PGB can be effective for neuropathic leg pain refractory to NSAIDs in LSS patients, resulting in not only pain control but also improving lower back pain-related ADL/QOL scores. PMID:27445615

  4. Pain modulation by intranasal oxytocin and emotional picture viewing - a randomized double-blind fMRI study.

    PubMed

    Zunhammer, Matthias; Geis, Sandra; Busch, Volker; Eichhammer, Peter; Greenlee, Mark W

    2016-01-01

    The hormone oxytocin has been hypothesized to influence the emotional dimension of pain. This randomized, placebo-controlled, double-blind, crossover study explored whether intranasal oxytocin and emotional context can affect heat pain perception in 30 healthy male volunteers. After receiving 36 IU oxytocin or placebo, participants underwent functional Magnetic Resonance Imaging (fMRI) during which noxious and non-noxious thermode heat stimuli were applied. Simultaneously, scenes from the International Affective Pictures System (IAPS) with positive, neutral, and negative emotional valence were shown. Heat intensity and unpleasantness ratings were obtained. The activity of whole-brain correlates of heat processing was quantified via multi-voxel pattern analysis. We observed no appreciable main effects of oxytocin on ratings or neural pain correlates. Effects of emotional picture valence on ratings were smaller than reported in previous studies. Nevertheless, oxytocin was found to significantly enhance the influence of picture valence on unpleasantness ratings at noxious heat levels. No corresponding changes in whole-brain correlates of heat intensity processing were found. Our study provides evidence that intranasal oxytocin increases the effects of emotional context on the subjective unpleasantness of experimental heat pain. Future studies are needed to determine whether this effect can be utilized in clinical settings. PMID:27546446

  5. Pain modulation by intranasal oxytocin and emotional picture viewing — a randomized double-blind fMRI study

    PubMed Central

    Zunhammer, Matthias; Geis, Sandra; Busch, Volker; Eichhammer, Peter; Greenlee, Mark W.

    2016-01-01

    The hormone oxytocin has been hypothesized to influence the emotional dimension of pain. This randomized, placebo-controlled, double-blind, crossover study explored whether intranasal oxytocin and emotional context can affect heat pain perception in 30 healthy male volunteers. After receiving 36 IU oxytocin or placebo, participants underwent functional Magnetic Resonance Imaging (fMRI) during which noxious and non-noxious thermode heat stimuli were applied. Simultaneously, scenes from the International Affective Pictures System (IAPS) with positive, neutral, and negative emotional valence were shown. Heat intensity and unpleasantness ratings were obtained. The activity of whole-brain correlates of heat processing was quantified via multi-voxel pattern analysis. We observed no appreciable main effects of oxytocin on ratings or neural pain correlates. Effects of emotional picture valence on ratings were smaller than reported in previous studies. Nevertheless, oxytocin was found to significantly enhance the influence of picture valence on unpleasantness ratings at noxious heat levels. No corresponding changes in whole-brain correlates of heat intensity processing were found. Our study provides evidence that intranasal oxytocin increases the effects of emotional context on the subjective unpleasantness of experimental heat pain. Future studies are needed to determine whether this effect can be utilized in clinical settings. PMID:27546446

  6. Diagnosis and Characters of Non-Specific Low Back Pain in Japan: The Yamaguchi Low Back Pain Study

    PubMed Central

    Suzuki, Hidenori; Kanchiku, Tsukasa; Imajo, Yasuaki; Yoshida, Yuichiro; Nishida, Norihiro; Taguchi, Toshihiko

    2016-01-01

    Study Design Cross sectional data from the Yamaguchi low back pain study conducted in Yamaguchi prefecture, Japan, was used for this analysis. Methods A total of 320 patients were recruited from walk-in orthopedic clinics in Yamaguchi Prefecture, Japan. Patients visited the clinics primarily for low back pain (LBP) and sought treatment between April and May 2015. A self-questionnaire was completed by patients, while radiographic testing and neurological and physical examination was performed by the orthopedist in each hospital. The cause and characters of LBP was determined following examination of the data, regional anesthesia and block injection. Results ‘Specific LBP’ was diagnosed in 250 (78%) patients and non-diagnosable, ‘non-specific LBP’ in 70 (22%) patients. The VAS scores of patients were: LBP, 5.8±0.18; leg pain, 2.9±0.18 and the intensity of leg numbness was 1.9±0.16. Item scores for SF-8 were: general health, 46.6±0.40; physical function, 43.5±0.51; physical limitations, 42.8±0.53; body pain, 42.1±0.52; vitality, 48.4±0.37; social function, 46.9±0.53; emotional problems, 48.9±0.43; mental health, 46.9±0.43. Conclusions The incidence of non-specific LBP in Japan was lower than previous reports from western countries, presumably because of variation in the diagnosis of LBP between different health care systems. In Japan, 78% of cases were classified as ‘specific LBP’ by orthopedists. Identification of the definitive cause of LBP should help to improve the quality of LBP treatment. PMID:27548658

  7. Double-blind randomized controlled study of coblation tonsillotomy versus coblation tonsillectomy on postoperative pain.

    PubMed

    Arya, A; Donne, A J; Nigam, A

    2003-12-01

    This double-blind randomized controlled trial of coblation tonsillotomy versus coblation tonsillectomy uses visual analogue scoring to compare the pain experienced in the 24h postoperative period. No statistically significant difference in pain is demonstrated in the group of 14 patients studied. Tonsillectomy is recommended over tonsillotomy.

  8. An Action Research Study Exploring How Education May Enhance Pain Management in Children.

    ERIC Educational Resources Information Center

    Simons, Joan M.

    2002-01-01

    Focus groups (n=14) and a study day (n=10) on pain management for child patients were held for pediatric nurses. Participants felt they increased their knowledge of pharmacology and their confidence and assertiveness in the practice of pain management. (Contains 37 references.) (SK)

  9. Being in Pain: A Phenomenological Study of Young People with Cerebral Palsy

    ERIC Educational Resources Information Center

    Castle, Kirstyn; Imms, Christine; Howie, Linsey

    2007-01-01

    This study explored the experience and impact of chronic pain on the lives of adolescents and young adults with cerebral palsy (CP). Six participants with CP (four males, two females; age range 14-24y) who were known to experience chronic pain participated in individual in-depth interviews. Five participants had quadriplegia and used wheelchairs;…

  10. The search for pain relief in people with chronic fatigue syndrome: a descriptive study.

    PubMed

    Marshall, Rebecca; Paul, Lorna; Wood, Les

    2011-07-01

    The purpose of this study was to investigate the use and perceived benefit of complimentary and alternative medicine (CAM) and physiotherapy treatments tried by people with chronic fatigue syndrome (CFS) to ease painful symptoms. This study used a descriptive, cross-sectional design. People with CFS who experienced pain were recruited to this study. Participants were asked during a semistructured interview about the treatments they had tried to relieve their pain. Each interview was conducted in the home of the participant. Fifty participants were recruited, of which, 10 participants were severely disabled by CFS. Eighteen participants were trying different forms of CAM treatment for pain relief at the time of assessment. Three participants were currently receiving physiotherapy. Throughout the duration of their illness 45 participants reported trying 19 different CAM treatments in the search for pain relief. Acupuncture was reported to provide the most pain relief (n=16). Twenty-seven participants reported a total of 16 different interventions prescribed by their physiotherapist. The results of this study suggest some physiotherapy and CAM treatments may help people manage painful CFS symptoms. Future research should be directed to evaluating the effectiveness of interventions such as acupuncture or gentle soft tissue therapies to reduce pain in people with CFS.

  11. A longitudinal study of the prevalence and characteristics of pain in the first 5 years following spinal cord injury.

    PubMed

    Siddall, Philip J; McClelland, Joan M; Rutkowski, Susan B; Cousins, Michael J

    2003-06-01

    A longitudinal cohort study of 100 people with traumatic spinal cord injury (SCI) was performed to determine the prevalence and severity of different types of pain (musculoskeletal, visceral, neuropathic at-level, neuropathic below-level) at 5 years following SCI. Prospective data on the characteristics of pain up to 6 months following injury had been collected previously and allowed comparisons between the presence of pain at different time points. In addition, we sought to determine the relationship between the presence of pain and physical factors related to the injury such as level of lesion, completeness and clinical SCI syndrome. We also obtained information regarding mood, global self-rated health and the impact of pain on function. Of the 100 subjects in the original cohort, 73 were available for follow up. When all types of pain were included, 59 of the 73 subjects (81%) reported the presence of pain. Musculoskeletal pain was the most common type of pain experienced and was present in 43 subjects (59%), at-level neuropathic pain was present in 30 subjects (41%), below-level neuropathic pain was present in 25 subjects (34%) and visceral pain was present in four subjects (5%). Overall, 58% reported their pain as severe or excruciating and those with visceral pain were most likely to rate their pain in these categories. There was no relationship between the presence of pain overall and level or completeness of lesion, or type of injury. However, tetraplegics were more likely to report below-level neuropathic pain. This study prospectively demonstrates the differing time courses of different types of pain over the first 5 years following SCI. There was a strong correlation between the presence of both types of neuropathic pain at 5 years and earlier time points but both visceral pain and musculoskeletal pain demonstrated a poor correlation between time points. Chronic visceral pain occurs in a small percentage of patients and does not correlate with the

  12. Inter-Hospital Variability of Postoperative Pain after Tonsillectomy: Prospective Registry-Based Multicentre Cohort Study

    PubMed Central

    Guntinas-Lichius, Orlando; Geißler, Katharina; Komann, Marcus; Schlattmann, Peter; Meissner, Winfried

    2016-01-01

    Objectives Although tonsillectomy is one of the most frequent and painful surgeries, the association between baseline and process parameters and postoperative pain are not fully understood. Methods A multicentre prospective cohort study using a web-based registry enrolled 1,527 women and 1,008 men aged 4 to 85 years from 52 German hospitals between 2006 and 2015. Maximal pain (MP) score the first day after surgery on a numeric rating scale (NRS) from 0 (no pain) to 10 (MP) was the main outcome parameter. Results The mean maximal pain score was 5.8±2.2 (median 6). Multivariable analysis revealed that female gender (Odds ratio [OR] = 1.33; 95% confidence interval [CI] = 1.12 to 1.56; p = 0.001), age <20 years (OR = 1.56; CI = 1.27 to 1.91; p<0.0001), no pain counselling (OR = 1.78; CI = 1.370 to 2.316; p<0.001), chronic pain (OR = 1.34; CI = 1.107 to 1.64; p = 0.004), and receiving opioids in recovery room (OR = 1.89; CI = 1.55 to 2.325; p<0.001) or on ward (OR = 1.79; CI = 1.42 to 2.27; p<0.001) were independently associated with higher experienced maximal postoperative pain (greater the median of 6). The effect of age on pain was not linear. Maximal pain increased in underage patients to a peak at the age of 18 to 20 years. From the age of ≥20 years on, maximal pain after tonsillectomy continuously decreased. Even after adjustment to all statistically important baseline and process parameters, there was substantial variability of maximal pain between hospitals with a heterogeneity variance of 0.31. Conclusion Many patients seem to receive insufficient or ineffective analgesia after tonsillectomy. Further research should address if populations at risk of higher postoperative pain such as females, younger patients or those with preexisting pain might profit from a special pain management protocol. Beyond classical demographical and process parameters the large variability between different hospitals is striking and indicates the existence of other unknown factors

  13. A Study on Factors Affecting Low Back Pain and Safety and Efficacy of NSAIDs in Acute Low Back Pain in a Tertiary Care Hospital of Western Nepal

    PubMed Central

    Bhattarai, Srijana; Chhetri, Himal Paudel; Alam, Kadir; Thapa, Pabin

    2013-01-01

    Introduction: Low back pain is characterized by a range of symptoms which include pain, muscle tension or stiffness, and is localized between the shoulder blades and the folds of the buttocks, with or without spreading to the legs. Non-Steroidal Anti Inflammatory Drugs (NSAIDs) are the drugs of choice which provide an analgesic effect for acute low back pain. Aim: To study the factors affecting low back pain, efficacy and safety of different non-steroidal anti-inflammatory drugs (aceclofenac, diclofenac, naproxen and nimesulide) in low back pain. Methodology: Data collection form and numeric pain rating scale were used as study tools for studying patients’ demographies and severities of pain respectively. Patients prescribed with aceclofenac 100 mg , diclofenac 100 mg, naproxen 500 mg and nimesulide 100 mg for acute low back pain at Orthopaedics Outpatients Department of Manipal Teaching Hospital, Nepal, were enrolled in this study. The decrease in pain scores was recorded on 5th and 10th days of follow-up and pain scores were calculated. Descriptive statistics and Kruskal Wallis non parametric test were used for analysis. Results: Among 150 patients, 67.3% were females (n=101). Low back pain was more prevalent (24.7%) in age-group of 59-68 years and a positive correlation was seen. Similarly, low back pain was found to be high among people involved in agriculture, heavy weight lifters and non smokers. The decrease in average pain scores was more in the patients treated with aceclofenac (4.83 ± 0.537), followed by that in those who were treated with naproxen (4.13 ± 0.067) and diclofenac (3.84 ± 0.086). The decrease in pain scores was found to be lowest among patients who were treated with nimesulide (2.11 ± 0.148). Nimesulide presented more number of side-effects than the comparative drugs. Conclusion: Different factors affect low back pain, such as age, gender, personal habit, posture, occupation, weight lifting. Aceclofenac showed greater decrease in pain

  14. Chronic Pain

    MedlinePlus

    ... adults. Common chronic pain complaints include headache, low back pain, cancer pain, arthritis pain, neurogenic pain (pain resulting ... Institute of Neurological Disorders and Stroke (NINDS). Low Back Pain Fact Sheet Back Pain information sheet compiled by ...

  15. Experimental Modeling of Proliferative Vitreoretinopathy. An Experimental Morphological Study.

    PubMed

    Khoroshilova-Maslova, I P; Leparskaya, N L; Nabieva, M M; Andreeva, L D

    2015-05-01

    A model of proliferative vitreoretinopathy induced by simultaneous intravitreal injection of recombinant IL-1β and platelet concentrate is created and its main morphological manifestations are studied on Chinchilla rabbits. The model reflects pathogenesis of proliferative vitreoretinopathy: epiretinal membrane with the formation of retinal plication, traction detachment of the retina; moderate inflammatory reaction in the uveal tract, in the optic nerve infundibulum, in the vitreous body; intact structural elements of the retina, dissociation of the retinal pigmented epithelium cells with their subsequent migration. The model is adequate to the clinical picture of proliferative vitreoretinopathy in humans, which recommends it for experimental studies of the efficiency of drug therapy and prevention of this disease. PMID:26033599

  16. Patients' Perception of Chronic-Pain-Related Patient-Provider Communication in Relation to Sociodemographic and Pain-Related Variables: A Cross-Sectional Nationwide Study.

    PubMed

    Jonsdottir, Thorbjorg; Gunnarsdottir, Sigridur; Oskarsson, Gudmundur K; Jonsdottir, Helga

    2016-10-01

    Pain is a personal experience and patient-provider communication therefore an essential part of diagnosis and treatment where the patient's perspective needs to be central. The aim of this descriptive cross-sectional study was to investigate chronic-pain-related patient-provider communication in the context of sociodemographic variables, pain variables, perceived outcome of care, and satisfaction with health care providers. A postal questionnaire measuring socio-demographic variables, pain characteristics, pain-related health care utilization and patient-provider communication was sent to a sample of 4,500 individuals randomly drawn from the national population of Iceland. A subsample reporting chronic pain and having visited a health care provider for pain the previous six months (n = 401) was analyzed. Relationships between patient-provider communication and other measured variables were tested using bivariate and multivariate statistics. The more chronic pain impaired health-related quality of life, the more provider control the patients perceived in the patient-provider communication. There was also a strong negative relationship between patients' perception of providers' support and openness to discussing symptoms, and satisfaction with health care provider. Patients' perception of their own control in patient-provider communication and involvement in decisions regarding care was related to sociodemographic variables (specifically, education and residence) but not to pain related variables. This study highlights the importance of assessing chronic pain in a broad spectrum, listening, and giving patients time and support to communicate chronic pain and how it affects their life situation. The more interfering the pain is, the more important this is. PMID:27553131

  17. Patients' Perception of Chronic-Pain-Related Patient-Provider Communication in Relation to Sociodemographic and Pain-Related Variables: A Cross-Sectional Nationwide Study.

    PubMed

    Jonsdottir, Thorbjorg; Gunnarsdottir, Sigridur; Oskarsson, Gudmundur K; Jonsdottir, Helga

    2016-10-01

    Pain is a personal experience and patient-provider communication therefore an essential part of diagnosis and treatment where the patient's perspective needs to be central. The aim of this descriptive cross-sectional study was to investigate chronic-pain-related patient-provider communication in the context of sociodemographic variables, pain variables, perceived outcome of care, and satisfaction with health care providers. A postal questionnaire measuring socio-demographic variables, pain characteristics, pain-related health care utilization and patient-provider communication was sent to a sample of 4,500 individuals randomly drawn from the national population of Iceland. A subsample reporting chronic pain and having visited a health care provider for pain the previous six months (n = 401) was analyzed. Relationships between patient-provider communication and other measured variables were tested using bivariate and multivariate statistics. The more chronic pain impaired health-related quality of life, the more provider control the patients perceived in the patient-provider communication. There was also a strong negative relationship between patients' perception of providers' support and openness to discussing symptoms, and satisfaction with health care provider. Patients' perception of their own control in patient-provider communication and involvement in decisions regarding care was related to sociodemographic variables (specifically, education and residence) but not to pain related variables. This study highlights the importance of assessing chronic pain in a broad spectrum, listening, and giving patients time and support to communicate chronic pain and how it affects their life situation. The more interfering the pain is, the more important this is.

  18. Spinal cord stimulation for predominant low back pain in failed back surgery syndrome: study protocol for an international multicenter randomized controlled trial (PROMISE study)

    PubMed Central

    2013-01-01

    Background Although results of case series support the use of spinal cord stimulation in failed back surgery syndrome patients with predominant low back pain, no confirmatory randomized controlled trial has been undertaken in this patient group to date. PROMISE is a multicenter, prospective, randomized, open-label, parallel-group study designed to compare the clinical effectiveness of spinal cord stimulation plus optimal medical management with optimal medical management alone in patients with failed back surgery syndrome and predominant low back pain. Method/Design Patients will be recruited in approximately 30 centers across Canada, Europe, and the United States. Eligible patients with low back pain exceeding leg pain and an average Numeric Pain Rating Scale score ≥5 for low back pain will be randomized 1:1 to spinal cord stimulation plus optimal medical management or to optimal medical management alone. The investigators will tailor individual optimal medical management treatment plans to their patients. Excluded from study treatments are intrathecal drug delivery, peripheral nerve stimulation, back surgery related to the original back pain complaint, and experimental therapies. Patients randomized to the spinal cord stimulation group will undergo trial stimulation, and if they achieve adequate low back pain relief a neurostimulation system using the Specify® 5-6-5 multi-column lead (Medtronic Inc., Minneapolis, MN, USA) will be implanted to capture low back pain preferentially in these patients. Outcome assessment will occur at baseline (pre-randomization) and at 1, 3, 6, 9, 12, 18, and 24 months post randomization. After the 6-month visit, patients can change treatment to that received by the other randomized group. The primary outcome is the proportion of patients with ≥50% reduction in low back pain at the 6-month visit. Additional outcomes include changes in low back and leg pain, functional disability, health-related quality of life, return to work

  19. Lumbar facet injection for the treatment of chronic piriformis myofascial pain syndrome: 52 case studies

    PubMed Central

    Huang, Jen-Ting; Chen, Han-Yu; Hong, Chang-Zern; Lin, Ming-Ta; Chou, Li-Wei; Chen, Hsin-Shui; Tsai, Chien-Tsung; Chang, Wen-Dien

    2014-01-01

    Background and aims The aim of this study was to demonstrate the effectiveness of lumbar facet joint injection for piriformis myofascial pain syndrome. Methods Fifty-two patients with chronic myofascial pain in the piriformis muscle each received a lumbar facet injection into the ipsilateral L5–S1 facet joint region, using the multiple insertion technique. Subjective pain intensity, trunk extension range, and lumbar facet signs were measured before, immediately after, and 2 weeks after injection. Thirty-six patients received follow-up for 6 months. Results Immediately after the injection, 27 patients (51.9%) had complete pain subsidence, 19 patients (36.5%) had pain reduction to a tolerable level, and only 6 patients (11.5%) had no pain relief to a tolerable level. Mean pain intensity was reduced from 7.4±0.9 to 1.6±2.1 after injection (P<0.01). This effectiveness lasted for 2 weeks in 49 patients (94.2%), and lasted for approximately 6 months in 35 (97.2%) of 36 patients. The mean range of motion increased from 13.4±6.8 degrees to 22.1±6.0 degrees immediately after injection, and further increased 2 weeks and 6 months later. Immediately after injection, 45 patients (86.5%) had no facet sign. In addition, 90.4% and 94.4% of patients had no facet sign after 2 weeks and after 6 months, respectively. Conclusions It is important to identify the possible cause of piriformis myofascial pain syndrome. If this pain is related to lumbar facet lesions, lumbar facet joint injection can immediately suppress piriformis myofascial pain symptoms. This effectiveness may last for at least 6 months in most patients. This study further supports the importance of eliminating the underlying etiological lesion for complete and effective relief of myofascial pain syndrome. PMID:25170256

  20. Is musculoskeletal pain a consequence or a cause of occupational stress? A longitudinal study

    PubMed Central

    Bonzini, M.; Bertu’, L.; Veronesi, G.; Ferrario, M. M.; Conti, M.; Coggon, D.; Bertu’, L.

    2015-01-01

    Objectives Longitudinal studies have linked stress at work with a higher incidence of musculoskeletal pain. We aimed to explore the extent to which musculoskeletal pain is a cause as opposed to a consequence of perceived occupational stress. Methods As part of the international CUPID study, we collected information from 305 Italian nurses, at baseline and again after 12 months, about pain during the past month in the low back and neck/shoulder, and about effort-reward imbalance (ERI) (assessed by Siegrist’s ERI questionnaire). Poisson regression was used to assess the RR of ERI >1 at follow-up according to report of pain and of ERI >1 at baseline. Results Among nurses with ERI ≤1at baseline, ERI >1 at follow-up was associated with baseline report of pain in the low back (RR=2.7, 95%CI1.4-5.0) and neck/shoulder (RR=2.6, 95%CI 1.3-5.1). However, there was no corresponding association with persistence of ERI in nurses who were already had ERI >1 at baseline. Associations of ERI at baseline with pain at follow-up were weak. Conclusions Our results suggest that the well documented association between job stress and musculoskeletal pain is not explained entirely by an effect of stress on reporting of pain. It appears also that workers who report musculoskeletal pain are more likely to develop subsequent perceptions of stress. This may be because pain renders people less tolerant of the psychological demands of work. Another possibility is that reports of pain and stress are both manifestations of a general tendency to be aware of and complain about symptoms and difficulties. PMID:25261316

  1. Perception and suppression of thermally induced pain: a fMRI study.

    PubMed

    Freund, W; Klug, R; Weber, F; Stuber, G; Schmitz, B; Wunderlich, A P

    2009-03-01

    Two neuroimaging studies using functional magnetic resonance imaging (fMRI) and thermally induced pain are presented. Fifteen healthy right-handed subjects were imaged while they had to discern different levels of thermal stimuli in the first study and while they disengaged from the feeling of pain during constant stimulation in the second study. In the first experiment, during painful phasic stimuli, right-sided anterior insular activation as well as bilateral posterior insular activation could be shown regardless of stimulation side, as well as right-sided activation of sensory association areas in the superior parietal lobule. Also, activation of the ipsilateral sensorimotor cortex could be shown. In the second experiment, all subjects succeeded in suppressing the feeling of pain during previously painful levels of stimulation. During the early part of the tonic painful stimulation, bilateral activation of caudate head and dorsolateral prefrontal cortex (DLPFC) as well as insular cortex and dorsal anterior cingulated cortex (dACC) was observed. During the late part of the tonic painful stimulation, anterior insular activation as well as dACC and bilateral prefrontal cortical activation could be shown. Taken together, the activation of PFC and caudate nucleus hints at an important role in the initiation (caudate) and maintenance (PFC) of suppression of the feeling of pain. No ipsilateral sensorimotor activation could be shown in the second experiment. The possible import of unwanted sensorimotor activation due to the simultaneous rating process in the first experiment is discussed.

  2. Effect of Isometric Quadriceps Exercise on Muscle Strength, Pain, and Function in Patients with Knee Osteoarthritis: A Randomized Controlled Study

    PubMed Central

    Anwer, Shahnawaz; Alghadir, Ahmad

    2014-01-01

    [Purpose] The aim of present study was to investigate the effects of isometric quadriceps exercise on muscle strength, pain, and function in knee osteoarthritis. [Subjects and Methods] Outpatients (N=42, 21 per group; age range 40–65 years; 13 men and 29 women) with osteoarthritis of the knee participated in the study. The experimental group performed isometric exercises including isometric quadriceps, straight leg raising, and isometric hip adduction exercise 5 days a week for 5 weeks, whereas the control group did not performed any exercise program. The outcome measures or dependent variables selected for this study were pain intensity, isometric quadriceps strength, and knee function. These variables were measured using the Numerical Rating Scale (NRS), strength gauge device, and reduced WOMAC index, respectively. All the measurements were taken at baseline (week 0) and at the end of the trial at week 5. [Results] In between-group comparisons, the maximum isometric quadriceps strength, reduction in pain intensity, and improvement in function in the isometric exercise group at the end of the 5th week were significantly greater than those of the control group (p<0.05). [Conclusion] The 5-week isometric quadriceps exercise program showed beneficial effects on quadriceps muscle strength, pain, and functional disability in patients with osteoarthritis of the knee. PMID:24926143

  3. Operant learning theory in pain and chronic pain rehabilitation.

    PubMed

    Gatzounis, Rena; Schrooten, Martien G S; Crombez, Geert; Vlaeyen, Johan W S

    2012-04-01

    The application of operant learning theory on chronic pain by Fordyce has had a huge impact on chronic pain research and management. The operant model focuses on pain behaviors as a major component of the pain problem, and postulates that they are subject to environmental contingencies. The role of operant learning in pain behaviors generally has been supported by experimental studies, which are reviewed in the present article. Subsequently, the rationale, goals, and methods of operant behavioral treatment of chronic pain are outlined. Special attention is paid to three therapeutic techniques (graded activity, activity pacing, and time-contingent medication management), which are discussed in detail with regard to their operationalization, effectiveness, and (possible) mechanisms of action. Criticisms of the operant model are presented, as are suggestions for the optimization of (operant) behavioral treatment efficacy.

  4. Expanding hypnotic pain management to the affective dimension of pain.

    PubMed

    Feldman, Jeffrey B

    2009-01-01

    Experimental (Price & Barber, 1987) and neuroimaging studies (Rainville, Carrier, Hofbauer, Bushnell, & Duncan, 1999), suggest that it is the affective dimension of pain as processed in the anterior cingulate cortex (ACC) that is most associated with suffering and autonomic arousal. Conversely, pain related emotions (Rainville, Bao, & Chretien, 2005) and expectations (Koyama, McHaffie, Laurenti, & Coghill, 2005) modulate pain perception and associated pain affect. This paper presents both the scientific background and the general clinical steps involved in a practical hypnotic approach that uses emotion specific wording and the elicitation of prior positive experience to intervene at both the affective and sensory dimensions of pain. Such an approach enables patients to therapeutically use hypnosis to reduce their subjective distress even if they are not able to greatly reduce the sensation of pain. The utilization of positive state dependent learning (Rossi, 1986), following the advice of Milton Erickson to "discover their patterns of happiness" (Parsons-Fein, 2005) is emphasized.

  5. Operant learning theory in pain and chronic pain rehabilitation.

    PubMed

    Gatzounis, Rena; Schrooten, Martien G S; Crombez, Geert; Vlaeyen, Johan W S

    2012-04-01

    The application of operant learning theory on chronic pain by Fordyce has had a huge impact on chronic pain research and management. The operant model focuses on pain behaviors as a major component of the pain problem, and postulates that they are subject to environmental contingencies. The role of operant learning in pain behaviors generally has been supported by experimental studies, which are reviewed in the present article. Subsequently, the rationale, goals, and methods of operant behavioral treatment of chronic pain are outlined. Special attention is paid to three therapeutic techniques (graded activity, activity pacing, and time-contingent medication management), which are discussed in detail with regard to their operationalization, effectiveness, and (possible) mechanisms of action. Criticisms of the operant model are presented, as are suggestions for the optimization of (operant) behavioral treatment efficacy. PMID:22261987

  6. The Pain in Neuropathy Study (PiNS): a cross-sectional observational study determining the somatosensory phenotype of painful and painless diabetic neuropathy

    PubMed Central

    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

  7. The Pain in Neuropathy Study (PiNS): a cross-sectional observational study determining the somatosensory phenotype of painful and painless diabetic neuropathy.

    PubMed

    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

    2016-05-01

    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

  8. Do psychological factors influence recovery from complex regional pain syndrome type 1? A prospective study.

    PubMed

    Bean, Debbie J; Johnson, Malcolm H; Heiss-Dunlop, Wolfgang; Lee, Arier C; Kydd, Robert R

    2015-11-01

    Previous studies have shown that the outcomes of complex regional pain syndrome (CRPS) vary significantly between patients, but few studies have identified prognostic indicators. The aim of this study was to determine whether psychological factors are associated with recovery from recently onset CRPS amongst patients followed prospectively for 1 year. Sixty-six patients with CRPS (type 1) were recruited within 12 weeks of symptom onset and assessed immediately and at 6 and 12 months, during which time they received treatment as usual. At each assessment, the following were measured: signs and symptoms of CRPS, pain, disability, depression, anxiety, stress, pain-related fear, pain catastrophising, laterality task performance, body perception disturbance, and perceived ownership of the limb. Mixed-effects models for repeated measures were conducted to identify baseline variables associated with CRPS severity, pain, and disability over the 12 months. Results showed that scores for all 3 outcome variables improved over the study period. Males and those with lower levels of baseline pain and disability experienced the lowest CRPS severity scores over 12 months. Those with lower baseline anxiety and disability had the lowest pain intensity over the study period, and those with lower baseline pain and pain-related fear experienced the least disability over the 12 months. This suggests that anxiety, pain-related fear, and disability are associated with poorer outcomes in CRPS and could be considered as target variables for early treatment. The findings support the theory that CRPS represents an aberrant protective response to perceived threat of tissue injury. PMID:26133727

  9. Pharmacological pain management in chronic pancreatitis

    PubMed Central

    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

  10. Subjective pain perception mediated by alpha rhythms.

    PubMed

    Peng, Weiwei; Babiloni, Claudio; Mao, Yanhui; Hu, Yong

    2015-07-01

    Suppression of spontaneous alpha oscillatory activities, interpreted as cortical excitability, was observed in response to both transient and tonic painful stimuli. The changes of alpha rhythms induced by pain could be modulated by painful sensory inputs, experimental tasks, and top-down cognitive regulations such as attention. The temporal and spatial characteristics, as well as neural functions of pain induced alpha responses, depend much on how these factors contribute to the observed alpha event-related desynchronization/synchronization (ERD/ERS). How sensory-, task-, and cognitive-related changes of alpha oscillatory activities interact in pain perception process is reviewed in the current study, and the following conclusions are made: (1) the functional inhibition hypothesis that has been proposed in auditory and visual modalities could be applied also in pain modality; (2) the neural functions of pain induced alpha ERD/ERS were highly dependent on the cortical regions where it is observed, e.g., somatosensory cortex alpha ERD/ERS in pain perception for painful stimulus processing; (3) the attention modulation of pain perception, i.e., influences on the sensory and affective dimensions of pain experience, could be mediated by changes of alpha rhythms. Finally, we propose a model regarding the determinants of pain related alpha oscillatory activity, i.e., sensory-discriminative, affective-motivational, and cognitive-modulative aspects of pain experience, would affect and determine pain related alpha oscillatory activities in an integrated way within the distributed alpha system. PMID:26026894

  11. Back pain prevalence and associated factors in children and adolescents: an epidemiological population study

    PubMed Central

    Noll, Matias; Candotti, Cláudia Tarragô; da Rosa, Bruna Nichele; Loss, Jefferson Fagundes

    2016-01-01

    ABSTRACT OBJECTIVE To identify the prevalence of back pain among Brazilian school children and the factors associated with this pain. METHODS All 1,720 schoolchildren from the fifth to the eight grade attending schools from the city of Teutonia, RS, Southern Brazil, were invited to participate in the study. From these, 1,597 children participated. We applied the Back Pain and Body Posture Evaluation Instrument. The dependent variable was back pain, while the independent one were demographic, socioeconomic, behavior and heredity data. The prevalence ratio was estimated by multivariate analysis using the Poisson regression model (α = 0.05). RESULTS The prevalence of back pain in the last three months was 55.7% (n = 802). The multivariate analysis showed that back pain is associated with the variables: sex, parents with back pain, weekly frequency of physical activity, daily time spent watching television, studying in bed, sitting posture to write and use the computer, and way of carrying the backpack. CONCLUSIONS The prevalence of back pain in schoolchildren is high and it is associated with demographic, behavior and heredity aspects. PMID:27305406

  12. A cross-sectional study investigating clinical predictors and physical experiences of pain in Parkinson’s disease

    PubMed Central

    Rana, Abdul Qayyum; Saeed, Usman; Masroor, Mohamed Sufian; Yousuf, Muhammad Saad; Siddiqui, Ishraq

    2013-01-01

    Summary Pain is a non-motor symptom of Parkinson’s disease (PD) that is often neglected due to its high prevalence in both the PD and the normal elderly population. The aims of this cross-sectional study were to establish the prevalence of pain, investigate its clinical predictors and analyze physical experiences of pain as described by PD patients. A total of 121 patients diagnosed with PD were included. The patients underwent a neurological examination and a structured interview and completed questionnaires focusing on clinical types and physical experiences of pain. Logistic regressions were used to analyze possible predictors. Pain was reported by 80 (66%) patients with a mean age at PD diagnosis of 67.26±11.43 years. The most common clinical types of pain experienced by the patients were dystonic pain (48%), paresthesia/neuropathic pain (36%) and musculoskeletal pain (28%). The PD patients described their physical experience of pain as aching (46%), a feeling of tension (18%), sharp pain (12%), deep pain (12%) and dull pain (11%). Patients with PD affecting the right side of the body were four times more likely to report pain on the right side of the body; however, no such relation was found for the left side of the body. A higher UPDRS-III scale score and longer PD duration reduced the likelihood of patients reporting dull pain. The presence of paresthesia/neuropathic pain was shown to decrease the likelihood of patients reporting sharp pain. No significant relationships were found between the magnitude of pain and gender, age at PD diagnosis, PD duration, UPDRS-III score, or Hoehn and Yahr stage of PD. Although 40% of the PD patients felt that medication had a (direct) effect on their pain, no relationship could be found between pain severity and PD medication. PMID:24598399

  13. Determinants of pain and functioning in knee osteoarthritis: a one-year prospective study

    PubMed Central

    Helminen, Eeva-Eerika; Sinikallio, Sanna H; Valjakka, Anna L; Väisänen-Rouvali, Rauni H; Arokoski, Jari PA

    2016-01-01

    Objective: To identify predictors of pain and disability in knee osteoarthritis. Design: A one-year prospective analysis of determinants of pain and functioning in knee osteoarthritis. Study setting: Primary care providers in a medium-sized city. Patients: A total of 111 patients aged from 35 to 75 with clinical symptoms and radiographic grading (Kellgren-Lawrence 2–4) of knee osteoarthritis who participated in a randomized controlled trial. Main measures: The outcome measures were self-reported pain and function, which were recorded at 0, 3 and 12 months. Disease-specific pain and functioning were assessed using the pain and function subscales of the Western Ontario and McMaster Universities (WOMAC) Osteoarthritis Index. Generic physical and mental functioning were assessed using the RAND-36 subscales for function, and physical and mental component summary scores. Possible baseline predictors for these outcomes were 1) demographic, socioeconomic and disease-related variables, and 2) psychological measures of resources, distress, fear of movement and catastrophizing. Results: Multivariate linear mixed model analyses revealed that normal mood at baseline measured with the Beck Anxiety Inventory predicted significantly better results in all measures of pain (WOMAC P=0.02) and function (WOMAC P=0.002, RAND-36 P=0.002) during the one-year follow-up. Psychological resource factors (pain self-efficacy P=0.012, satisfaction with life P=0.002) predicted better function (RAND-36). Pain catastrophizing predicted higher WOMAC pain levels (P=0.013), whereas fear of movement (kinesiophobia) predicted poorer functioning (WOMAC P=0.046, RAND-36 P=0.024). Conclusions: Multiple psychological factors in people with knee osteoarthritis pain are associated with the development of disability and longer term worse pain. PMID:27496698

  14. Planus Foot Posture and Pronated Foot Function are Associated with Foot Pain: The Framingham Foot Study

    PubMed Central

    Menz, Hylton B.; Dufour, Alyssa B.; Riskowski, Jody L.; Hillstrom, Howard J.; Hannan, Marian T.

    2014-01-01

    Objective To examine the associations of foot posture and foot function to foot pain. Methods Data were collected on 3,378 members of the Framingham Study who completed foot examinations in 2002–2008. Foot pain (generalized and at six locations) was based on the response to the question “On most days, do you have pain, aching or stiffness in either foot?” Foot posture was categorized as normal, planus or cavus using static pressure measurements of the arch index. Foot function was categorized as normal, pronated or supinated using the center of pressure excursion index from dynamic pressure measurements. Sex-specific multivariate logistic regression models were used to examine the effect of foot posture and function on generalized and location-specific foot pain, adjusting for age and weight. Results Planus foot posture was significantly associated with an increased likelihood of arch pain in men (odds ratio [OR] 1.38, 95% confidence interval [CI] 1.01 – 1.90), while cavus foot posture was protective against ball of foot pain (OR 0.74, 95% CI 0.55 – 1.00) and arch pain (OR 0.64, 95% CI 0.48 – 0.85) in women. Pronated foot function was significantly associated with an increased likelihood of generalized foot pain (OR 1.28, 95% CI 1.04 – 1.56) and heel pain (OR 1.54, 95% CI 1.04 – 2.27) in men, while supinated foot function was protective against hindfoot pain in women (OR 0.74, 95% CI 0.55 – 1.00). Conclusion Planus foot posture and pronated foot function are associated with foot symptoms. Interventions that modify abnormal foot posture and function may therefore have a role in the prevention and treatment of foot pain. PMID:23861176

  15. Primary and secondary somatosensory cortex responses to anticipation and pain: a magnetoencephalography study.

    PubMed

    Worthen, Siân F; Hobson, Anthony R; Hall, Stephen D; Aziz, Qasim; Furlong, Paul L

    2011-03-01

    Several brain regions, including the primary and secondary somatosensory cortices (SI and SII, respectively), are functionally active during the pain experience. Both of these regions are thought to be involved in the sensory-discriminative processing of pain and recent evidence suggests that SI in particular may also be involved in more affective processing. In this study we used MEG to investigate the hypothesis that frequency-specific oscillatory activity may be differentially associated with the sensory and affective components of pain. In eight healthy participants (four male), MEG was recorded during a visceral pain experiment comprising baseline, anticipation, pain and post-pain phases. Pain was delivered via intraluminal oesophageal balloon distension (four stimuli at 1 Hz). Significant bilateral but asymmetrical changes in neural activity occurred in the β-band within SI and SII. In SI, a continuous increase in neural activity occurred during the anticipation phase (20-30 Hz), which continued during the pain phase but at a lower frequency (10-15 Hz). In SII, oscillatory changes only occurred during the pain phase, predominantly in the 20-30 Hz β band, and were coincident with the stimulus. These data provide novel evidence of functional diversity within SI, indicating a role in attentional and sensory aspects of pain processing. In SII, oscillatory changes were predominantly stimulus-related, indicating a role in encoding the characteristics of the stimulus. We therefore provide objective evidence of functional heterogeneity within SI and functional segregation between SI and SII, and suggest that the temporal and frequency dynamics within cortical regions may offer valuable insights into pain processing.

  16. A preliminary study comparing the use of cervical/upper thoracic mobilization and manipulation for individuals with mechanical neck pain

    PubMed Central

    Griswold, David; Learman, Ken; O'Halloran, Bryan; Cleland, Josh

    2015-01-01

    Objectives: Neck pain is routinely managed using manual therapy (MT) to the cervical and thoracic spines. While both mobilizations and manipulations to these areas have been shown to reduce neck pain, increase cervical range of motion, and reduce disability, the most effective option remains elusive. The purpose of this preliminary trial was to compare the pragmatic use of cervical and thoracic mobilizations vs. manipulation for mechanical neck pain. Methods: This trial included 20 patients with mechanical neck pain. Each patient was randomized to receive either mobilization or manipulation to both the cervical and thoracic spines during their plan of care. Within-group analyses were made with Wilcoxon signed-rank tests and between-group analyses were made with Mann–Whitney U. Results: There were no between-group differences for any of the dependent variables including cervical active range of motion (CAROM) (P = 0.18), deep cervical flexion (DCF) endurance (P = 0.06), numerical pain rating scale (NPRS) (P = 0.26), the neck disability index (NDI, P = 0.33), patient-specific functional scale (PSFS, P = 0.20), or the global rating of change (GROC) scale (P = 0.94). Within-group results were significant for all outcome variables (P<0.001) from initial evaluation to discharge for both groups. Discussion: These findings were consistent with other trials previously conducted that applied the MT techniques in a pragmatic fashion, but varied from previous trials where the treatment was standardized. A larger experimental study is necessary to further examine the differences between mobilization and manipulation for neck pain. PMID:26109828

  17. Low back pain in car drivers: A review of studies published 1975 to 2005

    NASA Astrophysics Data System (ADS)

    Gallais, Lenka; Griffin, Michael J.

    2006-12-01

    This review investigates whether there is evidence of an association between car driving and low back pain, and evidence that whole-body vibration contributes to low back pain in car drivers. The evidence of an association between various physical, psychosocial and individual factors and low back pain in car drivers was also investigated. From 23 epidemiological studies of low back problems in groups that reported car driving, nine studies fulfilled simple criteria for detailed review: four cross-sectional studies, three case-control studies and two longitudinal studies. The definition of low back pain was often unclear and, mostly, the physiological mechanisms causing low back pain were not considered. Eight of the nine studies concluded that there was an increase in low back pain among car drivers but there was little consideration of the influence of the many physical factors, individual factors and psychosocial factors that might be associated with an increase in low back pain. Consequently, there is insufficient evidence to form a conclusion on whether whole-body vibration, postural stressors or other factors, specific or not specific to driving, are common causes of low back problems in car drivers.

  18. Functional abdominal pain in childhood: Background studies and recent research trends

    PubMed Central

    Levy, Rona L; van Tilburg, Miranda AL

    2012-01-01

    The present review summarizes many of the major research trends investigated in the past five years regarding pediatric functional abdominal pain, and also summarizes the primary related findings from the authors’ research program. Specific areas discussed based on work within the authors’ group include familial illness patterns, genetics, traits, and mechanisms or processes related to abdominal pain. Topics covered from research published in the past five years include prevalence and cost, longitudinal follow-up, overlap with other disorders, etiology and mechanisms behind functional abdominal pain and treatment studies. It is hoped that findings from this work in abdominal pain will be interpreted as a framework for understanding the processes by which other pain phenomena and, more broadly, reactions to any physical state, can be developed and maintained in children. The present article concludes with recommendations for clinical practice and research. PMID:23248815

  19. Occupational sitting behaviour and its relationship with back pain - A pilot study.

    PubMed

    Zemp, Roland; Fliesser, Michael; Wippert, Pia-Maria; Taylor, William R; Lorenzetti, Silvio

    2016-09-01

    Nowadays, working in an office environment is ubiquitous. At the same time, progressively more people suffer from occupational musculoskeletal disorders. Therefore, the aim of this pilot study was to analyse the influence of back pain on sitting behaviour in the office environment. A textile pressure mat (64-sensor-matrix) placed on the seat pan was used to identify the adopted sitting positions of 20 office workers by means of random forest classification. Additionally, two standardised questionnaires (Korff, BPI) were used to assess short and long-term back pain in order to divide the subjects into two groups (with and without back pain). Independent t-test indicated that subjects who registered back pain within the last 24 h showed a clear trend towards a more static sitting behaviour. Therefore, the developed sensor system has successfully been introduced to characterise and compare sitting behaviour of subjects with and without back pain.

  20. Occupational sitting behaviour and its relationship with back pain - A pilot study.

    PubMed

    Zemp, Roland; Fliesser, Michael; Wippert, Pia-Maria; Taylor, William R; Lorenzetti, Silvio

    2016-09-01

    Nowadays, working in an office environment is ubiquitous. At the same time, progressively more people suffer from occupational musculoskeletal disorders. Therefore, the aim of this pilot study was to analyse the influence of back pain on sitting behaviour in the office environment. A textile pressure mat (64-sensor-matrix) placed on the seat pan was used to identify the adopted sitting positions of 20 office workers by means of random forest classification. Additionally, two standardised questionnaires (Korff, BPI) were used to assess short and long-term back pain in order to divide the subjects into two groups (with and without back pain). Independent t-test indicated that subjects who registered back pain within the last 24 h showed a clear trend towards a more static sitting behaviour. Therefore, the developed sensor system has successfully been introduced to characterise and compare sitting behaviour of subjects with and without back pain. PMID:27184315

  1. The impact of baroreflex function on endogenous pain control: a microneurography study.

    PubMed

    Lautenschläger, Gothje; Habig, Kathrin; Best, Christoph; Kaps, Manfred; Elam, Mikael; Birklein, Frank; Krämer, Heidrun H

    2015-12-01

    The interaction between sympathetic vasoconstrictor activity to muscles [muscle sympathetic nerve activity (MSNA), burst frequency (BF) and burst incidence (BI)] and different stress and somatosensory stimuli is still unclear. Eighteen healthy men (median age 28 years) underwent microneurography recordings from the peroneal nerve. MSNA was recorded during heat pain (HP) and cold pain (CP) alone as well as combined with different stress tasks (mental arithmetic, singing, giving a speech). An additional nine healthy men (median age 26 years) underwent the stimulation protocol with an additional control task (thermal pain combined with listening to music) to evaluate possible attentional confounders. MSNA was significantly increased by CP and HP. CP-evoked responses were smaller. The diastolic blood pressure followed the time course of MSNA while heart rate remained unchanged. The mental stress tasks further increased MSNA and were sufficient to reduce pain while the control task had no effect. MSNA activity correlated negatively with pain intensity and positively with analgesia. High blood pressure values were associated with lower pain intensity. Our study indicates an impact of central sympathetic drive on pain and pain control. PMID:26454007

  2. The impact of baroreflex function on endogenous pain control: a microneurography study.

    PubMed

    Lautenschläger, Gothje; Habig, Kathrin; Best, Christoph; Kaps, Manfred; Elam, Mikael; Birklein, Frank; Krämer, Heidrun H

    2015-12-01

    The interaction between sympathetic vasoconstrictor activity to muscles [muscle sympathetic nerve activity (MSNA), burst frequency (BF) and burst incidence (BI)] and different stress and somatosensory stimuli is still unclear. Eighteen healthy men (median age 28 years) underwent microneurography recordings from the peroneal nerve. MSNA was recorded during heat pain (HP) and cold pain (CP) alone as well as combined with different stress tasks (mental arithmetic, singing, giving a speech). An additional nine healthy men (median age 26 years) underwent the stimulation protocol with an additional control task (thermal pain combined with listening to music) to evaluate possible attentional confounders. MSNA was significantly increased by CP and HP. CP-evoked responses were smaller. The diastolic blood pressure followed the time course of MSNA while heart rate remained unchanged. The mental stress tasks further increased MSNA and were sufficient to reduce pain while the control task had no effect. MSNA activity correlated negatively with pain intensity and positively with analgesia. High blood pressure values were associated with lower pain intensity. Our study indicates an impact of central sympathetic drive on pain and pain control.

  3. Using a healing touch intervention in older adults with persistent pain: a feasibility study.

    PubMed

    Decker, Sheila; Wardell, Diane Wind; Cron, Stanley G

    2012-09-01

    The purposes of this pilot study were to determine the feasibility of using a Healing Touch (HT) intervention with noncommunity-dwelling older adults experiencing persistent pain and to determine an HT protocol. Data were collected at multiple time points from 20 noncommunity-dwelling older adults experiencing pain. Residents were assigned to the HT group that included techniques specific for pain or a Presence Care group. Outcome variables included measures for pain, activities of daily living, and quality of life. The pain measures showed decreases that were not statistically significant for both groups. The measure for activities of daily living showed a non-statistically significant improvement over time for the HT group. Quality of life decreased for the HT group and improved for the Presence Care group although not significantly. The practitioners were able to complete all seven of the 30- minute HT sessions. The findings indicated that both groups showed some improvement in their pain scores with other measures being variable. HT is a feasible intervention for the elderly with pain. Overall, the findings highlight the complex nature of pain in older adults.

  4. Moral judgment modulates neural responses to the perception of other’s pain: an ERP study

    PubMed Central

    Cui, Fang; Ma, Ning; Luo, Yue-jia

    2016-01-01

    Morality and empathy are both crucial in building human society. Yet the relationship between them has been merely explored. The present study revealed how the morality influenced empathy for pain by comparing the ERPs elicited by pictures showing the targets’ in pain primed by different moral information about the targets. We found that when the target was a moral one or a neutral one, the painful pictures elicited significantly larger amplitude in N2 than the non-painful pictures, but when the target was an immoral one, the difference between the amplitudes of N2 component elicited by painful and non-painful pictures became insignificant. We proposed that this effect was induced by the decreased affective arousal when observing an immoral person in pain. The reduced neural response towards the immoral one’s pain can keep us alert when we face the potentially dangerous people thereby increasing our chance of survival. SLORTEA results showed the source of this difference in N2 localized in the ventral medial prefrontal cortex (vmPFC) and the rostral anterior cingulate cortex (rACC) areas. PMID:26865250

  5. Depressive symptoms and pain evaluations among persons with chronic pain: catastrophizing, but not pain acceptance, shows significant effects.

    PubMed

    Richardson, Elizabeth J; Ness, Timothy J; Doleys, Daniel M; Baños, James H; Cianfrini, Leanne; Richards, J Scott

    2009-12-15

    Cognitive factors such as catastrophic thoughts regarding pain, and conversely, one's acceptance of that pain, may affect emotional functioning among persons with chronic pain conditions. The aims of the present study were to examine the effects of both catastrophizing and acceptance on affective ratings of experimentally induced ischemic pain and also self-reports of depressive symptoms. Sixty-seven individuals with chronic back pain completed self-report measures of catastrophizing, acceptance, and depressive symptoms. In addition, participants underwent an ischemic pain induction procedure and were asked to rate the induced pain. Catastrophizing showed significant effects on sensory and intensity but not affective ratings of the induced pain. Acceptance did not show any significant associations, when catastrophizing was also in the model, with any form of ratings of the induced pain. Catastrophizing, but not acceptance, was also significantly associated with self-reported depressive symptoms when these two variables were both included in a regression model. Overall, results indicate negative thought patterns such as catastrophizing appear to be more closely related to outcomes of perceived pain severity and affect in persons with chronic pain exposed to an experimental laboratory pain stimulus than does more positive patterns as reflected in measures of acceptance.

  6. Prospective cohort study of predictors of incident low back pain in nurses.

    PubMed Central

    Smedley, J.; Egger, P.; Cooper, C.; Coggon, D.

    1997-01-01

    OBJECTIVE: To assess the impact of handling patients and indicators of individual susceptibility on risk of low back pain in nurses. DESIGN: Prospective cohort study with follow up by repeated self administered every three months over two years. SETTING: NHS university hospital trust. SUBJECTS: 961 female nurses who had been free from low back pain for at least one month at the time of completing a baseline questionnaire. MAIN OUTCOME MEASURES: Incidence of new low back pain during follow up and of pain leading to absence from work. RESULTS: Of 838 women who provided data suitable for analysis, 322 (38%) developed low back pain during follow up (mean 18.6 months), including 93 (11%) whose pain led to absence from work. The strongest predictor of new low back pain was earlier history of the symptom, and risk was particularly high if previous pain had lasted for over a month in total and had occurred within the 12 months before entry to the study (incidence during follow up 66%). Frequent low mood at baseline was strongly associated with subsequent absence from work for back pain (odds ratio 3.4; 95% confidence interval 1.4 to 8.2). After adjustment for earlier history of back pain and other potential confounders, risk was higher in nurses who reported frequent manual transfer of patients between bed and chair, manual repositioning of patients on the bed, and lifting patients in or out of the bath with a hoist. CONCLUSIONS: Of the indicators of individual susceptibility that were examined, only history of back trouble was sufficiently predictive to justify selective exclusion of some applicants for nursing posts. The main route to prevention of back disorders among nurses is likely to lie in improved ergonomics. PMID:9154024

  7. [Characterization of sensation disorders and neuropathic pain related to syringomyelia. A prospective study].

    PubMed

    Attal, N; Brasseur, L; Parker, F; Tadié, M; Bouhassira, D

    1999-06-01

    The present prospective study aimed to perform quantitative sensory testing (QST) in patients with painful or painless syringomyelia before and after surgical treatment of their syrinx (at 3 and 9 months). Eighteen consecutive patients with cervical or dorso-lumbar syringomyelia completed the study and 9 underwent surgery. Twelve patients had central neuropathic pain (of whom 6 were followed up). Spontaneous pain and brush-evoked allodynia were assessed. Von Frey hairs, vibrameter and a thermotest device were used to determine the mechanical-, vibratory-, thermal-detection thresholds, and the mechanical and thermal pain thresholds. Results showed evidence of deficits in temperature and pain sensibility in 17 cases, often associated with deficits in vibration and touch sensitivity (11 cases). Magnetic resonance scan, including axial images, demonstrated good correlation between paramedian extension of the syrinx and the laterality of thermal deficits. Somatosensory evoked potentials (11 patients) were abnormal in 9 cases at level, and showed good correlation with deficits in vibration. The magnitude of the thermal and tactile deficit was similar between areas of spontaneous pain and adjacent non painful areas. Surgery induced a significant decrease of tactile deficits, and to a lesser extent, of thermal deficits. Effects on neuropathic pain were positive in 3 patients (total disappearance of pain) and negligible or negative in 3 patients, despite collapse of the syrinx (in 2 cases). These results confirm that QST are useful in clinical practice to quantify the clinical results of surgery in patients with syringomyelia, and allow some hypotheses about the mechanisms of neuropathic pain in these patients.

  8. Attachment style moderates partner presence effects on pain: a laser-evoked potentials study.

    PubMed

    Krahé, Charlotte; Paloyelis, Yannis; Condon, Heather; Jenkinson, Paul M; Williams, Steven C R; Fotopoulou, Aikaterini

    2015-08-01

    Social support is crucial for psychological and physical well-being. Yet, in experimental and clinical pain research, the presence of others has been found to both attenuate and intensify pain. To investigate the factors underlying these mixed effects, we administered noxious laser stimuli to 39 healthy women while their romantic partner was present or absent, and measured pain ratings and laser-evoked potentials (LEPs) to assess the effects of partner presence on subjective pain experience and underlying neural processes. Further, we examined whether individual differences in adult attachment style (AAS), alone or in interaction with the partner's level of attentional focus (manipulated to be either on or away from the participant) might modulate these effects. We found that the effects of partner presence vs absence on pain-related measures depended on AAS but not partner attentional focus. The higher participants' attachment avoidance, the higher pain ratings and N2 and P2 local peak amplitudes were in the presence compared with the absence of the romantic partner. As LEPs are thought to reflect activity relating to the salience of events, our data suggest that partner presence may influence the perceived salience of events threatening the body, particularly in individuals who tend to mistrust others. PMID:25556212

  9. Attachment style moderates partner presence effects on pain: a laser-evoked potentials study.

    PubMed

    Krahé, Charlotte; Paloyelis, Yannis; Condon, Heather; Jenkinson, Paul M; Williams, Steven C R; Fotopoulou, Aikaterini

    2015-08-01

    Social support is crucial for psychological and physical well-being. Yet, in experimental and clinical pain research, the presence of others has been found to both attenuate and intensify pain. To investigate the factors underlying these mixed effects, we administered noxious laser stimuli to 39 healthy women while their romantic partner was present or absent, and measured pain ratings and laser-evoked potentials (LEPs) to assess the effects of partner presence on subjective pain experience and underlying neural processes. Further, we examined whether individual differences in adult attachment style (AAS), alone or in interaction with the partner's level of attentional focus (manipulated to be either on or away from the participant) might modulate these effects. We found that the effects of partner presence vs absence on pain-related measures depended on AAS but not partner attentional focus. The higher participants' attachment avoidance, the higher pain ratings and N2 and P2 local peak amplitudes were in the presence compared with the absence of the romantic partner. As LEPs are thought to reflect activity relating to the salience of events, our data suggest that partner presence may influence the perceived salience of events threatening the body, particularly in individuals who tend to mistrust others.

  10. Attachment style moderates partner presence effects on pain: a laser-evoked potentials study

    PubMed Central

    Paloyelis, Yannis; Condon, Heather; Jenkinson, Paul M.; Williams, Steven C. R.; Fotopoulou, Aikaterini

    2015-01-01

    Social support is crucial for psychological and physical well-being. Yet, in experimental and clinical pain research, the presence of others has been found to both attenuate and intensify pain. To investigate the factors underlying these mixed effects, we administered noxious laser stimuli to 39 healthy women while their romantic partner was present or absent, and measured pain ratings and laser-evoked potentials (LEPs) to assess the effects of partner presence on subjective pain experience and underlying neural processes. Further, we examined whether individual differences in adult attachment style (AAS), alone or in interaction with the partner’s level of attentional focus (manipulated to be either on or away from the participant) might modulate these effects. We found that the effects of partner presence vs absence on pain-related measures depended on AAS but not partner attentional focus. The higher participants’ attachment avoidance, the higher pain ratings and N2 and P2 local peak amplitudes were in the presence compared with the absence of the romantic partner. As LEPs are thought to reflect activity relating to the salience of events, our data suggest that partner presence may influence the perceived salience of events threatening the body, particularly in individuals who tend to mistrust others. PMID:25556212

  11. Relation between experimental and non-experimental study designs. HB vaccines: a case study

    PubMed Central

    Jefferson, T.; Demicheli, V.

    1999-01-01

    STUDY OBJECTIVE: To examine the relation between experimental and non- experimental study design in vaccinology. DESIGN: Assessment of each study design's capability of testing four aspects of vaccine performance, namely immunogenicity (the capacity to stimulate the immune system), duration of immunity conferred, incidence and seriousness of side effects, and number of infections prevented by vaccination. SETTING: Experimental and non-experimental studies on hepatitis B (HB) vaccines in the Cochrane Vaccines Field Database. RESULTS: Experimental and non-experimental vaccine study designs are frequently complementary but some aspects of vaccine quality can only be assessed by one of the types of study. More work needs to be done on the relation between study quality and its significance in terms of effect size.   PMID:10326054

  12. Temporal associations between spouse criticism/hostility and pain among patients with chronic pain: a within-couple daily diary study.

    PubMed

    Burns, John W; Peterson, Kristina M; Smith, David A; Keefe, Francis J; Porter, Laura S; Schuster, Erik; Kinner, Ellen

    2013-12-01

    Chronic musculoskeletal pain can strain marriages, perhaps even to the point of engendering spouse criticism and hostility directed toward patients. Such negative spouse responses may have detrimental effects on patient well-being. While results of cross-sectional studies support this notion, we extended these efforts by introducing expressed emotion (EE) and interpersonal theoretical perspectives, and by using electronic diary methods to capture both patient and spouse reports in a prospective design. Patients with chronic low back pain (CLBP) and their spouses (N = 105 couples) reported on perceived spouse behavior and patient pain 5 times/day for 14 days using Personal Data Assistants (PDAs). Concurrent and lagged within-couple associations between patient's perceptions of spouse criticism/hostility and patient self-reported pain and spouses' observations of patient pain behaviors revealed that (1) patient perceived spouse criticism and hostility were correlated significantly with pain intensity, and spouse observed patient pain behavior was related significantly with patient perceived hostility at the same time point; (2) patient perceived spouse hostility significantly predicted patient pain intensity 3 hours later, and spouse observed pain behaviors significantly predicted patient perceived spouse hostility 3 hours later. Results support both EE and interpersonal models, and imply that a comprehensive model would combine these conceptualizations to fully illustrate how spouse criticism/hostility and patient pain interact to produce a negative spiral. Given that marital interactions are amenable to clinical intervention, improved insight into how spouse behavior and patient pain are tightly linked will encourage productive translational efforts to target this neglected area.

  13. Experimental design of a waste glass study

    SciTech Connect

    Piepel, G.F.; Redgate, P.E.; Hrma, P.

    1995-04-01

    A Composition Variation Study (CVS) is being performed to support a future high-level waste glass plant at Hanford. A total of 147 glasses, covering a broad region of compositions melting at approximately 1150{degrees}C, were tested in five statistically designed experimental phases. This paper focuses on the goals, strategies, and techniques used in designing the five phases. The overall strategy was to investigate glass compositions on the boundary and interior of an experimental region defined by single- component, multiple-component, and property constraints. Statistical optimal experimental design techniques were used to cover various subregions of the experimental region in each phase. Empirical mixture models for glass properties (as functions of glass composition) from previous phases wee used in designing subsequent CVS phases.

  14. A descriptive study of Korean nurses' perception of pain and skin tearing at dressing change.

    PubMed

    Kim, Jung Yoon; Kim, Na Kyung; Lee, Yun Jin

    2016-03-01

    This study aimed to investigate Korean nurses' level of awareness of pain and skin tearing in wound bed and/or peri-wound skin at dressing change. A descriptive study was performed. Convenience sampling was employed and registered nurses were recruited from attendees of continuing education program. A total of 399 participants (RN) completed questionnaire. Data was collected from September to November 2014. Many of them perceived skin tearing and wound related pain associated with dressing changing, but most of them did not assess and record pain and skin tearing at dressing change. More than half of respondents reported that they did not provide nursing intervention to prevent pain and skin tearing. Many of them reported that a systematic educational program for preventing pain and skin tearing at dressing change was needed. In conclusion, many of respondents were aware of pain and skin tearing at dressing change, but did not take any further necessary measures, including nursing intervention, for the most appropriate, systematic pain and skin tearing management. Therefore, this study suggested that a systematic and comprehensive educational program for Korean healthcare professions needs to be developed and implemented in Korea's hospital settings. PMID:26847938

  15. Outcome Measure of Pain in Patients with Lumbar Disc Herniation: Validation Study of the Iranian version of Pain Sensitivity Questionnaire

    PubMed Central

    Azhari, Shirzad; Shahzadi, Sohrab; Nayeb Aghaei, Hossain; Mohammadi, Hassan Reza; Montazeri, Ali

    2016-01-01

    Study Design Cross-sectional. Purpose To translate and culturally adapt an Iranian version of the Pain Sensitivity Questionnaire (PSQ) in Iran. Overview of Literature Instruments measuring patient reported outcomes should satisfy certain psychometric properties. Methods The PSQ was translated following cross-cultural adaptation guidelines. A total of 101 patients with lumbar disc herniation (LDH), and 39 healthy cases were included in the study. All participants completed the PSQ and the Pain Catastrophizing Scale (PCS). The internal consistency, test-retest reliability, known group comparison, criterion validity and item-scale correlations were assessed. Results The mean age of participants was 51.7 years. Reliability, validity and correlation of PSQ and PCS showed satisfactory results. Cronbach's alpha coefficients were 0.81 for PSQ-total, 0.82 for PSQ-minor, and 0.82 for PSQ-moderate. The intraclass correlation coefficients value was 0.84 (0.616–0.932) indicating an excellent test-retest reliability. The instrument discriminated well between sub-groups of patients who differed in a standard predictive measure of LDH surgery (the Finneson–Cooper score). Total PSQ were also significantly correlated with the total scores of the PCS, lending support to its good convergent validity. Additionally, the correlation of each item with its hypothesized domain on the PSQ indicated acceptable results, suggesting that the items had a substantial relationship with their own domains. Conclusions The adapted Iranian PSQ is a valid and reliable questionnaire for the assessment of pain in patients with LDH. PMID:27340527

  16. Endogenous opioidergic dysregulation of pain in fibromyalgia: a PET and fMRI study.

    PubMed

    Schrepf, Andrew; Harper, Daniel E; Harte, Steven E; Wang, Heng; Ichesco, Eric; Hampson, Johnson P; Zubieta, Jon-Kar; Clauw, Daniel J; Harris, Richard E

    2016-10-01

    Endogenous opioid system dysfunction potentially contributes to chronic pain in fibromyalgia (FM), but it is unknown if this dysfunction is related to established neurobiological markers of hyperalgesia. We previously reported that µ-opioid receptor (MOR) availability was reduced in patients with FM as compared with healthy controls in several pain-processing brain regions. In the present study, we compared pain-evoked functional magnetic resonance imaging with endogenous MOR binding and clinical pain ratings in female opioid-naive patients with FM (n = 18) using whole-brain analyses and regions of interest from our previous research. Within antinociceptive brain regions, including the dorsolateral prefrontal cortex (r = 0.81, P < 0.001) and multiple regions of the anterior cingulate cortex (all r > 0.67; all P < 0.02), reduced MOR availability was associated with decreased pain-evoked neural activity. Additionally, reduced MOR availability was associated with lower brain activation in the nucleus accumbens (r = 0.47, P = 0.050). In many of these regions, pain-evoked activity and MOR binding potential were also associated with lower clinical affective pain ratings. These findings are the first to link endogenous opioid system tone to regional pain-evoked brain activity in a clinical pain population. Our data suggest that dysregulation of the endogenous opioid system in FM could lead to less excitation in antinociceptive brain regions by incoming noxious stimulation, resulting in the hyperalgesia and allodynia commonly observed in this population. We propose a conceptual model of affective pain dysregulation in FM.

  17. Perspective of Orthopedists on Pain Management in Osteoarthritis: A Qualitative Study

    PubMed Central

    Austine, Jose; Nair, Shoba; Mirza, Kiyana

    2016-01-01

    Context: Osteoarthritis (OA) is a degenerative disorder characterized by pain, stiffness, and loss of mobility of the joint. As the most prevalent form of arthritis and a leading cause of impairment, it is imperative to understand the treating doctor's perception of pain relief among these patients. Objectives: To assess orthopedists’ perspectives on pain management in OA. Materials and Methods: In this qualitative study, a guide-based interview was conducted on 15 orthopedists of a tertiary care hospital and audio-recorded simultaneously. A grounded theory approach was adopted for data transcription with an inductive approach for thematic manual analysis. Results: Five themes emerged - (1) quality of life: OA produces significant disease burden causing severe impairment; (2) pain management: although patients usually demand immediate pain relief, a multipronged approach to treatment emphasizing on physiotherapy and surgery rather than analgesics is needed. Most participants preferred individual discretion while others felt the need for systematizing pain management; (3) precautions/side effects of treatment: paracetamol is often prescribed due to its better benefit − adversity profile as compared to nonsteroidal anti-inflammatory drugs and weak opioids; (4) barriers: participants expressed several barriers to optimal pain management; (5) counseling: Participants concurred that counseling would improve patients’ quality of life. Conclusions: Participants agreed that OA being associated with debilitating pain and impairment requires optimal pain management for improving patients’ quality of life. As crucial as counseling is, it is often compromised due to the large outpatient load. The doctors concurred that a multi-disciplinary team approach is needed to integrate and optimize pain management in OA. PMID:27803562

  18. Progress in Genetic Studies of Pain and Analgesia

    PubMed Central

    LaCroix-Fralish, Michael L.

    2009-01-01

    Interindividual variability in pain sensitivity and the response to analgesic manipulations remains a considerable clinical challenge as well as an area of intense scientific investigation. Techniques in this field have matured rapidly so that much relevant data have emerged only in the past few years. Our increasing understanding of the genetic mediation of these biological phenomena have nonetheless revealed their surprising complexity. This review provides a comprehensive picture and critical analysis of the field and its prospects. PMID:18834308

  19. A Multi-centered Cross-sectional Study of Disease Burden of Pain of Inpatients in Southwest China

    PubMed Central

    Peng, Li-Hua; Jing, Ju-Yin; Qin, Pei-Pei; Su, Min

    2016-01-01

    Background: Pain is a common burden of disease globally; yet, it is not systematically investigated in China, especially in hospitalized patients. This study was aimed at clarifying the epidemiological characteristics of pain and related factors in hospitalized patients in Southwest China. Methods: A cross-sectional study was conducted to investigate the prevalence, severity, and influencing factors of pain and modes of postoperative analgesia in hospitalized patients from 17 hospitals in Southwest China. A prevalidated questionnaire was employed to calibrate all of these items within 3 days from March 18, 2015 to March 20, 2015. Results: A total of 2293 patients were surveyed, the incidence of pain was 57.4% in all hospitalized patients at rest, of which 62.1% were with acute pain and 37.9% had persistent to chronic pain. Among surgical patients, 90.8% of them complained of acute postoperative pain at rest and 97.1% in motion. The incidence of acute postoperative moderate-to-severe pain was 28.8% at rest and 45.1% in motion. Surgical patients reported higher incidences of pain, especially acute and persistent pain compared with nonsurgical patients (P < 0.05). Postoperative pain occurred predominately at surgical sites (95.2%) as compared with nonsurgical sites (4.8%). Agedness, lower education level, surgery, and history of smoking were factors associated with increased duration and severity of postoperative pain and nonsurgical pain (P < 0.05). Conclusions: Pain is a common burden of disease in China, of which surgical pain constituted an important component. Surgical patients complained more severe pain than those who did not undergo surgery. Postoperative analgesia still needs to be improved to control pain after surgery. Patients' perception might influence the efficacy of pain management, which should be implemented with a multidisciplinary approach. PMID:27064038

  20. [Potentialities and limitations of hypnosis for the treatment of pain].

    PubMed

    Peter, B

    1998-07-10

    With regard to the potentialities of hypnosis for the treatment of pain, relevant studies on hypnotic pain control are discussed. Studies with experimentally produced pain unanimously show that hypnosis is effective in controlling pain, whereas clinical studies are much more ambiguous in this respect. Three basic strategies of hypnotic pain control are outlined to which the different techniques can be subsumed: dissociative, associative, and symbolic strategies. Accountable for the limitations of hypnosis are some issues like hypnotic state, hypnotizability, rapport, hypnotic techniques, and pain as a multifactorial process. These issues are discussed and their contribution to contraindications are outlined. Especially the differences between symptom- and problem-oriented hypnotic approaches are highlighted.

  1. Musculoskeletal neck and back pain in undergraduate dental students at a UK dental school - a cross-sectional study.

    PubMed

    Vijay, S; Ide, M

    2016-09-01

    Objective Limited data exist on musculoskeletal problems within dental students: we aimed to determine the prevalence of these disorders.Design Single centre cross-sectional study.Setting A UK Dental School 2015.Methods Students completed a modified Nordic pain questionnaire.Main outcome measures Self-reported frequency and severity of pain, fitness and coping strategies.Results 63% of 390 respondents were female and 75% aged under 23. Seventy-nine percent experienced pain with 42% experiencing pain for 30 or more days in the past year. Lower back pain was most common (54%) and was most frequently the worst area of pain (48%). Thirty-six percent reported pain lasting at least four hours. The mean 'average pain intensity' VAS score was 3.81/10 (sd = 1.75) and mean 'worst pain intensity' was 5.56 (sd = 2.10). More females reported neck pain (58% versus 37%, P <0.001) and higher 'average pain intensity' (mean 4.02, sd 1.82 versus 3.43 sd 1.55, P = 0.012. Daily stretching was used by 55.7% of respondents, and this positively correlated with 'average' and 'worst pain intensity' (P = 0.096 and P = 0.001) scores. Eighteen percent sought professional help to manage pain.Conclusion Musculoskeletal pain is a problem for dental students. Education in self-care may be helpful; however, assessments of possible interventions are needed. PMID:27608577

  2. The study of pain with blood oxygen level dependent functional magnetic resonance imaging

    NASA Astrophysics Data System (ADS)

    Ibinson, James W.

    Using blood oxygen level dependent functional magnetic resonance imaging (BOLD FMRI), the brain areas activated by pain were studied. These initial studies led to interesting new findings about the body's response to pain and to the refinement of one method used in FMRI analysis for correction of physiologic noise (signal fluctuations caused by the cyclic and non-cyclic changes in the cardiovascular and respiratory status of the body). In the first study, evidence was provided suggesting that the multiple painful stimulations used in typical pain FMRI block designs may cause attenuation over time of the BOLD signal within activated areas. The effect this may have on pain investigations using multiple tasks has not been previously investigated. The demonstrated BOLD attenuation seems unique to pain studies. Several possible explanations exist, but two of the most likely are neural activity modulation by descending pain inhibitory mechanisms and changing hemodynamics caused by a physiologic response to pain. The second study began the investigation of hemodynamics by monitoring the physiologic response to pain for eight subjects in two phases. Phase one used a combination of standard operating suite monitors and research equipment to characterizing the physiologic response to pain. Phase two collected magnetic resonance quantitative flow images during painful nerve stimulation to test for changes in global cerebral blood flow. It is well established that changes in respiration and global blood flow can affect the BOLD response, leading to the final investigation of this dissertation. The brain activation induced by pain for the same eight subjects used in the physiologic response experiments described above was then studied by BOLD FMRI. By including the respiration signal and end-tidal carbon dioxide levels in the analysis of the images, the quantification and removal of image intensity variations correlated to breathing and end-tidal carbon dioxide changes could be

  3. Development and validation of a screening tool to predict the risk of chronic low back pain in patients presenting with acute low back pain: a study protocol

    PubMed Central

    Traeger, Adrian; Henschke, Nicholas; Hübscher, Markus; Williams, Christopher M; Kamper, Steven J; Maher, Chris G; Moseley, G Lorimer; McAuley, James H

    2015-01-01

    Introduction Around 40% of people presenting to primary care with an episode of acute low back pain develop chronic low back pain. In order to reduce the risk of developing chronic low back pain, effective secondary prevention strategies are needed. Early identification of at-risk patients allows clinicians to make informed decisions based on prognostic profile, and researchers to select appropriate participants for secondary prevention trials. The aim of this study is to develop and validate a prognostic screening tool that identifies patients with acute low back pain in primary care who are at risk of developing chronic low back pain. This paper describes the methods and analysis plan for the development and validation of the tool. Methods/analysis The prognostic screening tool will be developed using methods recommended by the Prognosis Research Strategy (PROGRESS) Group and reported using the Transparent Reporting of a multivariable prediction model for Individual Prognosis Or Diagnosis (TRIPOD) statement. In the development stage, we will use data from 1248 patients recruited for a prospective cohort study of acute low back pain in primary care. We will construct 3 logistic regression models to predict chronic low back pain according to 3 definitions: any pain, high pain and disability at 3 months. In the validation stage, we will use data from a separate sample of 1643 patients with acute low back pain to assess the performance of each prognostic model. We will produce validation plots showing Nagelkerke R2 and Brier score (overall performance), area under the curve statistic (discrimination) and the calibration slope and intercept (calibration). Ethics and dissemination Ethical approval from the University of Sydney Ethics Committee was obtained for both of the original studies that we plan to analyse using the methods outlined in this protocol (Henschke et al, ref 11-2002/3/3144; Williams et al, ref 11638). PMID:26179647

  4. Efficacy of coblation annuloplasty in discogenic low back pain: a prospective observational study.

    PubMed

    He, Liangliang; Hu, Xiangyu; Tang, Yuanzhang; Li, Xiuhua; Zheng, Shuyue; Ni, Jiaxiang

    2015-05-01

    In degenerative disc, the innervated outer annulus is confirmed to the major origin resulted in discogenic pain. To alleviate the discogenic pain, annuloplasty with electrothermal technology was proved to be effective, which mainly involves the thermal heating of the annulus to denature collagen fibers and denervate posterior annular nerve fibers. However, little is known that efficacy of annuloplasty with coblation technology in treating discogenic pain through directly interrupting nerves in outer annulus.The purpose of this study was to evaluate the clinical outcomes of coblation annuloplasty for the treatment of discogenic low back pain.In a clinical prospective observational study, 17 consecutive patients with discogenic low back pain underwent coblation annuloplasty under local anesthesia. Pain visual analogue scale (VAS) scores, patient responses stating significant (≥50%) pain relief, and modified MacNab criteria were adopted to evaluate the pain intensity, degree of pain relief, and functional status after 6 months of follow-up.The preoperative pain VAS score was 6.5 ± 0.8(95% confidence interval [CI] 6.1-6.9) and the pain VAS score decreased to 2.9 ± 1.6 (95% CI 2.1-3.8), 2.9 ± 1.7 (95% CI 2.1-3.8), 3.2 ± 1.6 (95% CI 2.4-4.1), 3.2 ± 1.7 (95% CI 2.4-4.2) at 1 week and 1, 3 and 6 month postoperatively, respectively. 12 (70.6%), 11 (64.7%), 10 (58.8%) and 10 (58.8%) of patients reported significant pain relief at 1 week and 1, 3 and 6 months postoperatively. At 1, 3, and 6 months postoperatively, the numbers of patients with "excellent" or "good" ratings