Interdisciplinary strategies to prevent long-term and detrimental opioid use following trauma: a stakeholder consensus study.

OBJECTIVE: Prolonged opioid use is common following traumatic injuries. Although preventive strategies have been recommended, the evidence supporting their use is low. The objectives of this study were to select interdisciplinary strategies to prevent long-term, detrimental opioid use in trauma patients for further evaluation and to identify implementation considerations. DESIGN: A consensus study using the nominal group technique. SETTING: Four trauma systems in Canada. SUBJECTS: Participants included expert clinicians and decision makers, and people with lived experience. METHODS: Participants had to discuss the relevance and implementation of 15 strategies and then rank them using a 7-point Likert scale. Implementation considerations were identified through a synthesis of discussions. RESULTS: A total of 41 expert stakeholders formed the nominal groups. Overall, eight strategies were favored: 1) using multimodal approach for pain management, 2) professional follow-up in physical health, 3) assessment of risk factors for opioid misuse, 4) physical stimulation, 5) downward adjustment of opioids based on patient recovery, 6) educational intervention for patients, 7) training offered to professionals on how to prescribe opioids, and 8) optimizing communication between professionals working in different settings. Discussions with expert stakeholders revealed the rationale for the selected strategies and identified issues to consider when implementing them. CONCLUSION: This stakeholder consensus study identified, for further scientific study, a set of interdisciplinary strategies to promote appropriate opioid use following traumatic injuries. These strategies could ultimately decrease the burden associated with long-term opioid use.

Strategies to prevent long-term opioid use following trauma: a Canadian practice survey.

PURPOSE: To evaluate how Canadian clinicians involved in trauma patient care and prescribing opioids perceive the use and effectiveness of strategies to prevent long-term opioid therapy following trauma. Barriers and facilitators to the implementation of these strategies were also assessed. METHODS: We conducted a web-based cross-sectional survey. Potential participants were identified by trauma program managers and directors of the targeted departments in three Canadian provinces. We designed our questionnaire using standard health survey research methods. The questionnaire was administered between April 2021 and November 2021. RESULTS: Our response rate was 47% (350/744), and 52% (181/350) of participants completed the entire survey. Most respondents (71%, 129/181) worked in teaching hospitals. Multimodal analgesia (93%, 240/257), nonsteroidal anti-inflammatory agents (77%, 198/257), and physical stimulation (75%, 193/257) were the strategies perceived to be the most frequently used. Several preventive strategies were perceived to be very effective by over 80% of respondents. Of these, some that were reported as not being frequently used were perceived to be among the most effective ones, including guidelines or protocols, assessing risk factors for opioid misuse, physical health follow-up by a professional, training for clinicians, patient education, and prescription monitoring systems. Staff shortages, time constraints, and organizational practices were identified as the main barriers to the implementation of the highest ranked preventive strategies. CONCLUSIONS: Several strategies to prevent long-term opioid therapy following trauma are perceived as being effective by those prescribing opioids in this population. Some of these strategies appear to be commonly used in everyday practice and others less so. Future research should focus on which preventive strategies should be given higher priority for implementation before assessing their effectiveness.

RéSUMé: OBJECTIF: Évaluer comment les cliniciens canadiens impliqués dans les soins aux patients traumatisés et prescrivant des opioïdes perçoivent l'utilisation et l'efficacité des stratégies visant à prévenir le traitement prolongé par opioïde après un traumatisme. Les obstacles et facilitateurs de la mise en œuvre de ces stratégies ont aussi été analysés. MéTHODES: Nous avons réalisé une enquête transversale via le Web. Les participants potentiels ont été identifiés par les gestionnaires et directeurs de programmes de traumatologie des départements ciblés dans trois provinces canadiennes. Nous avons conçu notre questionnaire en utilisant la méthodologie de recherche usuelle des enquêtes de santé. Le questionnaire a été administré entre avril 2021 et novembre 2021. RéSULTATS: Notre taux de réponse a été de 47 % (350/744) et 52 % (181/350) des participants ont complété l'enquête dans sa totalité. La majorité des personnes interrogées (71 %, 129/181) travaillait dans des hôpitaux universitaires. L'analgésie multimodale (93 %, 240/257), les anti-inflammatoires non stéroïdiens (77 %, 198/257) et la stimulation physique (75 %, 193/257) étaient les stratégies perçues comme étant le plus fréquemment utilisées. Plusieurs stratégies préventives étaient perçues comme étant très efficaces par plus de 80 % des répondants. Parmi celles-ci, certaines étaient signalées comme n'étant pas utilisées très souvent, mais perçues comme étant les plus efficaces, notamment les lignes directrices et protocoles évaluant les facteurs de risque d'utilisation abusive des opioïdes, le suivi de la santé physique par un professionnel, la formation des cliniciens, l'éducation des patients et les systèmes de suivi des prescriptions. La pénurie de personnels, les contraintes de temps et les pratiques de l'établissement ont été identifiées comme étant les principaux obstacles à la mise en place des stratégies préventives classées parmi les premières. CONCLUSIONS: Plusieurs stratégies de prévention du traitement par opioïdes à long terme après un traumatisme sont perçues comme efficaces par ceux qui les prescrivent à cette population de patients. Certaines de ces stratégies apparaissent comme couramment utilisées dans la pratique quotidienne et d'autres moins souvent. La recherche future devrait se concentrer sur la détermination des stratégies préventives auxquelles il faudrait accorder la plus grande priorité de mise en œuvre avant d'évaluer leur efficacité.

The Influence of Expectancies on Pain and Function Over Time After Total Knee Arthroplasty.

OBJECTIVE: Expectancies have a well-documented influence on the experience of pain, responses to treatment, and postsurgical outcomes. In individuals with osteoarthritis, several studies have shown that expectations predict increased pain and disability after total knee replacement surgery. Despite the growing recognition of the importance of expectancies in clinical settings, few studies have examined the influence of expectancies throughout postsurgical recovery trajectories. The objective of the present study was to examine the role of presurgical expectancies on pain and function at 6-week, 6-month, and 1-year follow-ups after total knee arthroplasty. DESIGN AND PARTICIPANTS: Data were collected from patients scheduled for total knee arthroplasty 1 week before surgery and then at 6 weeks, 6 months, and 1 year after surgery. Correlational and multivariable regression analyses examined the influence of expectancies on patients' perceptions of pain reduction and functional improvement at each time point. Analyses controlled for age, sex, body mass index, presurgical pain intensity and function, pain catastrophizing, anxiety, and depression. RESULTS: Results revealed that expectancies significantly predicted pain reduction and functional improvement at 1-year follow-up. However, expectancies did not predict outcomes at the 6-week and 6-month follow-ups. Catastrophizing and depressive symptoms emerged as short-term predictors of postsurgical functional limitations at 6-week and 6-month follow-ups, respectively. CONCLUSIONS: The results suggest that targeting high levels of catastrophizing and depressive symptoms could optimize short-term recovery after total knee arthroplasty. However, the results demonstrate that targeting presurgical negative expectancies could prevent prolonged recovery trajectories, characterized by pain and loss of function up to 1 year after total knee arthroplasty.

Strategies aimed at preventing chronic opioid use in trauma and acute care surgery: a scoping review protocol.

INTRODUCTION: Globally every year, millions of patients sustain traumatic injuries and require acute care surgeries. A high incidence of chronic opioid use (up to 58%) has been documented in these populations with significant negative individual and societal impacts. Despite the importance of this public health issue, optimal strategies to limit the chronic use of opioids after trauma and acute care surgery are not clear. We aim to identify existing strategies to prevent chronic opioid use in these populations. METHODS AND ANALYSIS: We will perform a scoping review of peer-reviewed and non-peer-reviewed literature to identify studies, reviews, recommendations and guidelines on strategies aimed at preventing chronic opioid use in patients after trauma and acute care surgery. We will search MEDLINE, EMBASE, PsycINFO, CINHAL, Cochrane Central Register of Controlled Trials, Web of Science, ProQuest and websites of trauma and acute care surgery, pain, government and professional organisations. Databases will be searched for papers published from 1 January 2005 to a maximum of 6 months before submission of the final manuscript. Two reviewers will independently evaluate studies for eligibility and extract data from included studies using a standardised data abstraction form. Preventive strategies will be classified according to their types and targeted trauma populations and acute care surgery procedures. ETHICS AND DISSEMINATION: Research ethics approval is not required as this study is based on the secondary use of published data. This work will inform research and clinical stakeholders on the required next steps towards the uptake of effective strategies aimed at preventing chronic opioid use in trauma and acute care surgery patients.

Opioid versus opioid-free analgesia after surgical discharge: protocol for a systematic review and meta-analysis.

INTRODUCTION: Excessive prescribing after surgery has contributed to a public health crisis of opioid addiction and overdose in North America. However, the value of prescribing opioids to manage postoperative pain after surgical discharge remains unclear. We propose a systematic review and meta-analysis to assess the extent to which opioid analgesia impact postoperative pain intensity and adverse events in comparison to opioid-free analgesia in patients discharged after surgery. METHODS AND ANALYSIS: Major electronic databases (MEDLINE, Embase, Cochrane Library, Scopus, AMED, BIOSIS, CINAHL and PsycINFO) will be searched for multi-dose randomised-trials examining the comparative effectiveness of opioid versus opioid-free analgesia after surgical discharge. Studies published from January 1990 to July 2019 will be targeted, with no language restrictions. The search will be re-run before manuscript submission to include most recent literature. We will consider studies involving patients undergoing minor and major surgery. Teams of reviewers will, independently and in duplicate, assess eligibility, extract data and evaluate risk of bias. Our main outcomes of interest are pain intensity and postoperative vomiting. Study results will be pooled using random effects models. When trials report outcomes for a common domain (eg, pain intensity) using different scales, we will convert effect sizes to a common standard metric (eg, Visual Analogue Scale). Minimally important clinical differences reported in previous literature will be considered when interpreting results. Subgroup analyses defined a priori will be conducted to explore heterogeneity. Risk of bias will be assessed according to the Cochrane Collaboration's Risk of Bias Tool 2.0. The quality of evidence for all outcomes will be evaluated using the GRADE rating system. ETHICS AND DISSEMINATION: Ethical approval is not required since this is a systematic review of published studies. Our results will be published in a peer-reviewed journal and presented at relevant conferences. Further knowledge dissemination will be sought via public and patient organisations focussed on pain and opioid-related harms.

Operationalization of the new Pain and Disability Drivers Management model: A modified Delphi survey of multidisciplinary pain management experts.

BACKGROUND: We recently proposed the Pain and Disability Drivers Management (PDDM) model, which was designed to outline comprehensive factors driving pain and disability in low back pain (LBP). Although we have hypothesized and proposed 41 elements, which make up the model's five domains, we have yet to assess the external validity of the PDDM's elements by expert consensus. RESEARCH OBJECTIVES: This study aimed to reach consensus among experts regarding the different elements that should be included in each domain of the PDDM model. RELEVANCE: The PDDM may assist clinicians and researchers in the delivery of targeted care and ultimately enhance treatment outcomes in LBP. METHODS: Using a modified Delphi survey, a two-round online questionnaire was administered to a group of experts in musculoskeletal pain management. Participants were asked to rate the relevance of each element proposed within the model. Participants were also invited to add and rate new elements. Consensus was defined by a greater than or equal to 75% level of agreement. RESULTS: A total of 47 (round 1) and 33 (round 2) participants completed the survey. Following the first round, 38 of 41 of the former model elements reached consensus, and 10 new elements were proposed and later rated in the second round. Following this second round, consensus was reached for all elements (10 new + 3 from first round), generating a final model composed of 51 elements. CONCLUSION: This expert consensus-derived list of clinical elements related to the management of LBP represents a first step in the validation of the PDDM model.

The moderating role of pain catastrophizing on the relationship between partner support and pain intensity: a daily diary study in patients with knee osteoarthritis.

The objective of this study was to examine the day-to-day associations between partner support, pain catastrophizing and pain intensity in individuals with end-stage knee osteoarthritis. In this microlongitudinal cohort study, participants (N = 124) with end-stage knee osteoarthritis completed baseline measures of trait pain catastrophizing and negative affect. Participants also provided daily diary assessments of partner support, pain catastrophizing and pain intensity for a period of 7 days using a personal digital assistant. Multilevel analyses revealed that day-to-day fluctuations in pain catastrophizing were associated with pain intensity. Data from multilevel analyses indicated that the main effect of partner support was not significantly associated with pain intensity. Results also indicated the interactions between partner support and both trait and state pain catastrophizing were significant, suggesting that both trait and state pain catastrophizing moderated the relationship between daily partner support and pain intensity. That is, on days when participants experienced low levels of partner support, high catastrophizers reported higher levels of pain intensity than low catastrophizers. In the presence of higher levels of partner support, pain intensity did not differ between high and low catastrophizers. These results are consistent with the Communal Coping Model of pain catastrophizing, and highlight the interpersonal context within which pain catastrophizing impacts pain outcomes. These findings also suggest that future interventions designed to specifically target the dynamic between pain catastrophizing and partner support may improve pain outcomes in individuals with end-stage knee OA.

Development and validation of the Treatment Expectations in Chronic Pain Scale.

OBJECTIVES: To develop and examine the psychometric properties of the Treatment Expectations in Chronic Pain (TEC) scale, a brief measure of treatment expectations of chronic non-cancer pain treatment. DESIGN: A cross-sectional study design was used. METHODS: After conducting a literature review and expert discussions, a preliminary version of the TEC scale was developed. Cognitive interviews with 10 clinicians and 14 patients were conducted to examine the scale's face validity and item wording. Last, two hundred and five patients on the waitlist for a multidisciplinary pain treatment centre completed a battery of self-report questionnaires to examine the TEC scale's reliability and construct validity. Mokken scale analysis was conducted to select the final items. Reliability (Cronbach's alpha and Guttman's lambda2 ) and construct validity (Pearson correlations) were assessed. RESULTS: The final scale was composed of nine items that each measured ideal and predicted expectations about process and outcome of treatment. Mokken scale analysis showed the presence of two subscales: ideal and predicted expectations. The TEC scale had good internal consistency (α = 0.876-0.869) and adequate discriminant validity as assessed by its low correlation with measures of depression, anxiety, and quality of life (r = -.038 to .114). The scale had however low correlation with a theoretically related measure of optimism (r = .240). CONCLUSION: The TEC scale is a reliable scale measuring pain treatment expectation. Further evaluation of its psychometric properties is needed. The scale has the potential to deepen our understanding of the role treatment expectations play in chronic non-cancer pain treatment response. Statement of contribution What is already known on this subject? Expectations play a role in pain perception and the response to pain treatment Patients' expectations about pain and its management are associated with treatment satisfaction The absence of a validated tool to measure treatment expectations in chronic non-cancer pain prevents further exploration and understanding of the role of expectations in the context of multidisciplinary pain treatment . What does this study add? A new, reliable 9-item scale measuring treatment expectations among chronic non-cancer pain patients attending specialized multidisciplinary pain clinics .

What do you expect? Catastrophizing mediates associations between expectancies and pain-facilitatory processes.

BACKGROUND: Pain expectancies are associated with altered pain sensitivity in individuals with chronic pain. However, little is known about the processes by which pain expectancies impact pain processing. This study assessed the association between pain expectancies and temporal summation (TS) of pain, and examined whether pain catastrophizing mediated this association. METHODS: In this cross-sectional study, participants (437 chronic low back pain [CLBP] patients, 115 controls) completed self-report measures of pain intensity, pain expectancies and pain catastrophizing before undergoing psychophysical pain-testing procedures designed to assess mechanical TS of mechanical pain. Pearson's correlations examined the associations between study variables in CLBP patients and controls. Bootstrapping mediation analyses assessed the mediating role of pain catastrophizing on the association between pain expectancies and TS of pain. RESULTS: Temporal summation of pain was significantly associated with pain expectancies (r = 0.113) and pain catastrophizing (r = 0.171) in CLBP patients. Results of mediation analyses revealed that pain catastrophizing mediated the relationship between pain expectancies and TS of pain in CLBP patients (ab = 0.309, 95% CI = 0.1222-0.5604), but not in healthy controls (ab = -0.125, 95% CI = -0.5864 to 0.0244). CONCLUSIONS: The findings from this study suggest that compared to controls, CLBP patients show increased sensitivity to mechanical pain procedures and enhanced pain-facilitatory processing, proving further evidence for changes in central nervous system pain processing in CLBP patients. Our results also suggest that pain catastrophizing may be the mechanism by which pain expectancies are associated with TS of pain in CLBP patients. SIGNIFICANCE: Individuals with chronic low back pain who expect higher levels of pain and catastrophize about their pain are more likely to experience altered pain sensitivity. Our results point to catastrophizing as a mechanism of action through which psychological factors may operate and lead to the development and maintenance of chronic low back pain.

Rehabilitation management of low back pain - it's time to pull it all together!

In the past, rehabilitation research initiatives for low back pain (LBP) have targeted outcome enhancement through personalized treatment approaches, namely through classification systems (CS). Although the use of CS has enhanced outcomes, common management practices have not changed, the prevalence of LBP is still high, and only selected patients meet the CS profile, namely those with a nociceptive context. Similarly, although practice guidelines propose some level of organization and occasionally a timeline of care provision, each mainly provides best practice for isolated treatment approaches. Moreover, there is no theoretical framework that has been proposed that guides the rehabilitation management process of mechanical LBP. In this commentary, we propose a model constituted of five domains (nociceptive drivers, nervous system dysfunction drivers, comorbidities drivers, cognitive-emotional drivers, and contextual drivers) grounded as mechanisms driving pain and/or disability in LBP. Each domain is linked to the International Classification of Functioning, Disability and Health, where once a patient is deemed suitable for rehabilitation, the clinician assesses elements of each domain in order to identify where the relative treatment efforts should be focused. This theoretical model is designed to provide a more comprehensive management overview, by appreciating the relative contribution of each domain driving pain and disability. Considering that the multiple domains driving pain and disability, and their interaction, requires a model that is comprehensive enough to identify and address each related issue, we consider that the proposed model has several positive implications for rehabilitation of this painful and highly prevalent musculoskeletal disorder.

Pain behavior mediates the relationship between perceived injustice and opioid prescription for chronic pain: a Collaborative Health Outcomes Information Registry study.

BACKGROUND AND PURPOSE: Perceived injustice has been defined as an appraisal regarding the severity and irreparability of loss associated with pain, blame and a sense of unfairness. Recent findings have identified perceived injustice as an important risk factor for pain-related outcomes. Studies suggest that perceived injustice is associated with opioid prescription in patients with pain conditions. However, the mechanisms by which perceived injustice is linked to opioid prescription are not well understood. The primary objective of this study was to examine the potential mediating roles of pain intensity, depressive symptoms and pain behavior in the association between perceived injustice and opioid prescription among patients with chronic pain. METHODS: This cross-sectional study used a sample of 344 patients with chronic pain being treated at a tertiary pain treatment center. Participants completed measures of perceived injustice, pain intensity, depressive symptoms, pain behavior and opioid prescription. Bootstrapped multiple mediation analyses were used to examine the mediating role of patients' pain intensity, depressive symptoms and pain behavior in the association between perceived injustice and opioid prescription. RESULTS: Consistent with previous research, we found a significant association between perceived injustice and opioid prescription. Interestingly, results revealed that pain behavior was the only variable that mediated the association between perceived injustice and opioid prescription. CONCLUSION: This study was the first to examine the mechanisms by which perceived injustice is associated with opioid prescription in patients with chronic pain. We found that pain behavior, rather than pain intensity and depressive symptoms, mediated the association between perceived injustice and opioid prescription. Future research in this area should employ a longitudinal research design in order to arrive at clearer causal conclusions about the relationships between pain behavior, perceived injustice and opioid prescription.

Multiple faces of pain: effects of chronic pain on the brain regulation of facial expression.

Pain behaviors are shaped by social demands and learning processes, and chronic pain has been previously suggested to affect their meaning. In this study, we combined functional magnetic resonance imaging with in-scanner video recording during thermal pain stimulations and use multilevel mediation analyses to study the brain mediators of pain facial expressions and the perception of pain intensity (self-reports) in healthy individuals and patients with chronic back pain (CBP). Behavioral data showed that the relation between pain expression and pain report was disrupted in CBP. In both patients with CBP and healthy controls, brain activity varying on a trial-by-trial basis with pain facial expressions was mainly located in the primary motor cortex and completely dissociated from the pattern of brain activity varying with pain intensity ratings. Stronger activity was observed in CBP specifically during pain facial expressions in several nonmotor brain regions such as the medial prefrontal cortex, the precuneus, and the medial temporal lobe. In sharp contrast, no moderating effect of chronic pain was observed on brain activity associated with pain intensity ratings. Our results demonstrate that pain facial expressions and pain intensity ratings reflect different aspects of pain processing and support psychosocial models of pain suggesting that distinctive mechanisms are involved in the regulation of pain behaviors in chronic pain.

The lateral prefrontal cortex mediates the hyperalgesic effects of negative cognitions in chronic pain patients.

UNLABELLED: Although high levels of negative affect and cognitions have been associated with greater pain sensitivity in chronic pain conditions, the neural mechanisms mediating the hyperalgesic effect of psychological factors in patients with pain disorders are largely unknown. In this cross-sectional study, we hypothesized that 1) catastrophizing modulates brain responses to pain anticipation and 2) anticipatory brain activity mediates the hyperalgesic effect of different levels of catastrophizing in fibromyalgia (FM) patients. Using functional magnetic resonance imaging, we scanned the brains of 31 FM patients exposed to visual cues anticipating the onset of moderately intense deep-tissue pain stimuli. Our results indicated the existence of a negative association between catastrophizing and pain-anticipatory brain activity, including in the right lateral prefrontal cortex. A bootstrapped mediation analysis revealed that pain-anticipatory activity in the lateral prefrontal cortex mediates the association between catastrophizing and pain sensitivity. These findings highlight the role of the lateral prefrontal cortex in the pathophysiology of FM-related hyperalgesia and suggest that deficits in the recruitment of pain-inhibitory brain circuitry during pain-anticipatory periods may play an important contributory role in the association between various degrees of widespread hyperalgesia in FM and levels of catastrophizing, a well-validated measure of negative cognitions and psychological distress. PERSPECTIVE: This article highlights the presence of alterations in pain-anticipatory brain activity in FM. These findings provide the rationale for the development of psychological or neurofeedback-based techniques aimed at modifying patients' negative affect and cognitions toward pain.

The two sides of pain communication: effects of pain expressiveness on vicarious brain responses revealed in chronic back pain patients.

UNLABELLED: The dominant socioaffective model of empathy has emphasized the overlap between brain mechanisms involved in the encoding and the decoding of internal states. The role of dispositional empathy has been extensively studied in this research, but several other individual factors fundamental to communication processes have been largely ignored. We studied the effects of dispositional expressiveness in chronic back pain patients to determine if the decoding of communicative and noncommunicative information signaling pain in others would be enhanced in individuals displaying a spontaneous propensity to consistently express more pain during a behavioral-observational naturalistic standardized lifting task performed on 2 separate occasions. Blood oxygenation level-dependent signal change was measured in response to pictures showing facial pain expressions and hands/feet in pain-evoking situations in chronic back pain patients and healthy controls. Vicarious brain responses to others' pain were comparable between groups. However, more expressive patients rated others' pain higher and showed stronger vicarious pain responses in the right ventral part of the inferior frontal gyrus, the right insula, and the midbrain. Activity in the right insula correlated positively with both the patients' expressiveness (encoding) and the intensity of the pain perceived in the images (decoding), suggesting that this structure linked the dispositional expressiveness with vicarious pain perception. Importantly, these effects were independent from dispositional empathy and were found with both communicative (facial expression) and noncommunicative (hand and foot) cues. These results suggest that dispositional expressiveness is a self-related factor that facilitates vicarious pain processing and might reflect individual tendencies to rely on social coping strategies. PERSPECTIVE: This article shows that pain expressivity in chronic pain patients increased the vicarious brain responses and the sensibility to others' pain. These results may help provide empirical support for better defining models of pain communication in chronic pain patients.

The stress model of chronic pain: evidence from basal cortisol and hippocampal structure and function in humans.

Recent theories have suggested that chronic pain could be partly maintained by maladaptive physiological responses of the organism facing a recurrent stressor. The present study examined the associations between basal levels of cortisol collected over seven consecutive days, the hippocampal volumes and brain activation to thermal stimulations administered in 16 patients with chronic back pain and 18 healthy control subjects. Results showed that patients with chronic back pain have higher levels of cortisol than control subjects. In these patients, higher cortisol was associated with smaller hippocampal volume and stronger pain-evoked activity in the anterior parahippocampal gyrus, a region involved in anticipatory anxiety and associative learning. Importantly, path modelling-a statistical approach used to examine the empirical validity of propositions grounded on previous literature-revealed that the cortisol levels and phasic pain responses in the parahippocampal gyrus mediated a negative association between the hippocampal volume and the chronic pain intensity. These findings support a stress model of chronic pain suggesting that the sustained endocrine stress response observed in individuals with a smaller hippocampii induces changes in the function of the hippocampal complex that may contribute to the persistent pain states.

The expression of pain behaviors in high catastrophizers: the influence of automatic and controlled processes.

UNLABELLED: In the present study, patients with musculoskeletal pain conditions (n = 55) were filmed while performing a lifting task designed to elicit pain behaviors. Patients were asked to perform the lifting task twice, under 2 distinct conditions. In the first condition, patients were asked to rate their pain while lifting a series of weights. In the second condition, patients were asked to estimate the weight of the objects they lifted. The weight estimation condition was conceived as a way to increase the cognitive load associated with the lifting task. The primary purpose of the present study was to examine whether manipulation of cognitive load differentially influenced the expression of pain behaviors in high and low catastrophizers. During the pain rating condition, results indicated that high catastrophizers displayed significantly higher levels of communicative and protective pain behaviors than low catastrophizers. During the weight estimation condition, however, high and low catastrophizers no longer differed in the expression of communicative pain behaviors. These results suggest that increasing cognitive load during a pain-eliciting task may interfere with the expression of communicative pain behaviors in high catastrophizers. The discussion addresses the potential role of automatic and cognitive control processes in the expression of pain behaviors. PERSPECTIVE: The present study provides new insights into the processes that might underlie the expression of pain behaviors in patients with high levels of catastrophizing. Our findings could have implications for the management of patients presenting with pain conditions, particularly those with high levels of catastrophizing.

Catastrophizing and perceived injustice: risk factors for the transition to chronicity after whiplash injury.

STUDY DESIGN: The article will summarize research that has supported the role of pain catastrophizing and perceived injustice as risk factors for problematic recovery after whiplash injury. OBJECTIVE: This article focuses on two psychological variables that have been shown to impact on recovery trajectories after whiplash injury; namely pain catastrophizing and perceived injustice. SUMMARY OF BACKGROUND DATA: Research has shown that psychological variables play a role in determining the trajectory of recovery after whiplash injury. METHODS: This article will focus on two psychological variables that have been shown to impact on recovery trajectories after whiplash injury; namely pain catastrophizing and perceived injustice. The article will summarize research that has supported the role of pain catastrophizing and perceived injustice as risk factors for problematic recovery after whiplash injury. RESULTS: Several investigations have shown that measures of catastrophizing and perceived injustice prospectively predict problematic trajectories of recovery after whiplash injury. Basic research points to the potential roles of expectancies, attention, coping and endogenous opioid dysregulation as possible avenues through which catastrophizing might heighten the probability of the persistence of pain after whiplash injury. Although research has yet to systematically address the mechanisms by which perceived injustice might contribute to prolonged disability in individuals with whiplash injuries, there are grounds for suggesting the potential contributions of catastrophizing, pain behavior and anger. CONCLUSION: A challenge for future research will be the development and evaluation of risk factor-targeted interventions aimed at reducing catastrophizing and perceived injustice to improve recovery trajectories after whiplash injury.

A randomized, controlled clinical trial of in virtuo and in vivo exposure for spider phobia.

The present study compared the efficacy of virtual reality (VR) in virtuo exposure and in vivo exposure in the treatment of spider phobia. Two treatment conditions were compared to a waiting-list condition. A 3-month follow-up evaluation was conducted in order to assess the durability of the treatment effects. Participants were randomly assigned to the treatment groups. A total of 16 participants received the in virtuo treatment, and 16 received the in vivo treatment. The waiting-list condition included 11 participants. Participants received eight 1.5-hour treatment sessions. Efficacy was measured with the Fear of Spiders Questionnaire, the Spider Beliefs Questionnaire (SBQ-F), and a Behavioral Avoidance Test (BAT). In addition, a clinician administered the Structured Interview for DSM-IV to assess DSM-IV's criteria for specific phobia and severity. Clinical and statistically significant improvements were found for both groups. Differences in treatment groups were found on one of five measures of fear: greater improvement on the SBQ-F beliefs subscale was associated with in vivo exposure.