Recommendations for a core outcome measurement set for clinical trials in whiplash associated disorders.

ABSTRACT: Inconsistent reporting of outcomes in clinical trials of treatments for whiplash associated disorders (WAD) hinders effective data pooling and conclusions about treatment effectiveness. A multidisciplinary International Steering Committee recently recommended 6 core outcome domains: Physical Functioning, Perceived Recovery, Work and Social Functioning, Psychological Functioning, Quality of Life and Pain. This study aimed to reach consensus and recommend a core outcome set (COS) representing each of the 6 domains. Forty-three patient-reported outcome measures (PROMs) were identified for Physical Functioning, 2 for perceived recovery, 37 for psychological functioning, 17 for quality of life, and 2 for pain intensity. They were appraised in 5 systematic reviews following COSMIN methodology. No PROMs of Work and Social Functioning in WAD were identified. No PROMs had undergone evaluation of content validity in patients with WAD, but some had moderate-to-high-quality evidence for sufficient internal structure. Based on these results, the International Steering Committee reached 100% consensus to recommend the following COS: Neck Disability Index or Whiplash Disability Questionnaire (Physical Functioning), the Global Rating of Change Scale (Perceived Recovery), one of the Pictorial Fear of Activity Scale-Cervical, Pain Self-Efficacy Questionnaire, Pain Catastrophizing Scale, Harvard Trauma Questionnaire, or Posttraumatic Diagnostic Scale (Psychological Functioning), EQ-5D-3L or SF-6D (Quality of Life), numeric pain rating scale or visual analogue scale (Pain), and single-item questions pertaining to current work status and percent of usual work (Work and Social Functioning). These recommendations reflect the current status of research of PROMs of the 6 core outcome domains and may be modified as evidence grows.

Swedish Chronic Pain Biobank: protocol for a multicentre registry and biomarker project.

INTRODUCTION: About 20% of the adult population have chronic pain, often associated with psychological distress, sick leave and poor health. There are large variations in the clinical picture. A biopsychosocial approach is used in investigation and treatment. The concept of personalised medicine, that is, optimising medication types and dosages for individual patients based on biomarkers and other patient-related factors, has received increasing attention in different diseases but used less in chronic pain. This cooperative project from all Swedish University Hospitals will investigate whether there are changes in inflammation and metabolism patterns in saliva and blood in chronic pain patients and whether the changes correlate with clinical characteristics and rehabilitation outcomes. METHODS AND ANALYSIS: Patients at multidisciplinary pain centres at University Hospitals in Sweden who have chosen to participate in the Swedish Quality Registry for Pain Rehabilitation and healthy sex-matched and age-matched individuals will be included in the study. Saliva and blood samples will be collected in addition to questionnaire data obtained from the register. From the samples, proteins, lipids, metabolites and micro-RNA will be analysed in relation to, for example, diagnosis, pain characteristics, psychological distress, body weight, pharmacological treatment and clinical rehabilitation results using advanced multivariate data analysis and bioinformatics. ETHICS AND DISSEMINATION: The study is approved by the Swedish Ethical Review Authority (Dnr 2021-04929) and will be conducted in accordance with the declaration of Helsinki.The results will be published in open access scientific journals and in popular scientific relevant journals such as those from patient organisations. Data will be also presented in scientific meetings, meeting with healthcare organisations and disseminated in different lecturers at the clinics and universities.

Exercise therapy for whiplash-associated disorders: a systematic review and meta-analysis.

OBJECTIVES: Acute as well as chronic pain syndromes are common after whiplash trauma and exercise therapy is proposed as one possible intervention strategy. The aim of the present systematic review was to evaluate the effect of exercise therapy in patients with Whiplash-Associated Disorders for the improvement of neck pain and neck disability, compared with other therapeutic interventions, placebo interventions, no treatment, or waiting list. CONTENT: The review was registered in Prospero (CRD42017060356) and conducted in accordance with the PRISMA (Preferred Reporting Items for Systematic Reviews and Meta-Analyses) guidelines. A literature search in PubMed, Scopus and Cochrane from inception until January 13, 2020 was combined with a hand search to identify eligible randomized controlled studies. Abstract screening, full text assessment and risk of bias assessment (Cochrane RoB 2.0) were conducted by two independent reviewers. SUMMARY: The search identified 4,103 articles. After removal of duplicates, screening of 2,921 abstracts and full text assessment of 100 articles, 27 articles that reported data for 2,127 patients were included. The included articles evaluated the effect of exercise therapy on neck pain, neck disability or other outcome measures and indicated some positive effects from exercise, but many studies lacked control groups not receiving active treatment. Studies on exercise that could be included in the random-effect meta-analysis showed significant short-term effects on neck pain and medium-term effects on neck disability. OUTLOOK: Despite a large number of articles published in the area of exercise therapy and Whiplash-Associated Disorders, the current evidence base is weak. The results from the present review with meta-analysis suggests that exercise therapy may provide additional effect for improvement of neck pain and disability in patients with Whiplash-Associated Disorders.

[Pain rehabilitation starts with a pain analysis]. / Långvarig smärta kräver teambaserad rehabilitering.

Pain rehabilitation is a process starting with a pain analysis to find an adequate pain diagnosis, a classification based on pain mechanisms and a mapping of the psychological and social situation of the patient. These factors are the basis for the treatment plan. Monodisciplinary treatments such as pharmacological treatments, physiotherapy, or psychological therapy, should be tested first if judged to improve the overall situation in a permanent manner. Patients with a complex situation can be subject to pain rehabilitation (interdisciplinary multimodal pain rehabilitation, IMMPR). IMMPR involves a coordinated effort of healthcare professionals with expertise in pain management aiming to reduce psychological distress, increase work ability and return to normal social activities and improve general health and life quality. Follow-up of patients undergoing IMMPR is routinely done by means of the Swedish Quality Registry for Pain Rehabilitation (SQRP), including rehabilitation in Primary Care and at specialized pain units.

The feasibility of gym-based exercise therapy for patients with persistent neck pain.

Background and aims Persistent neck pain is common and can be detrimental to the health of those who are affected. This is particularly common after neck trauma, where it poses a challenge to health care providers. In this paper, we present the design and results of a study aimed primarily at assessing the feasibility of a supervised exercise intervention for patients with persistent neck pain after trauma. As a secondary aim, we analyzed the results of the intervention. Methods We designed and conducted a feasibility study using a mixed methods design. Ten patients with persistent neck pain (nine with a history of neck trauma and one with sudden onset of neck pain) were recruited from a specialized pain rehabilitation center and underwent a gym-based individual exercise therapy intervention, supervised by a physical therapist. We assessed the feasibility of the exercise therapy intervention based on the experiences of the patients and physical therapists. We analyzed both quantitative and qualitative results using descriptive statistics, content analysis, and questionnaires. Results The study found the exercise therapy to be a feasible alternative for patients with persistent neck pain. Most of the practical aspects of the intervention and study were executed as planned, and the study was well received by the patients, who found it a valuable part of their rehabilitation. In the quantitative analysis, improvements were observed on the Neck Disability Index, numerical rating scale for pain, EuroQol 5D, and physical activity, with scores on the Neck Disability Index showing a statistically significant improvement. Scores on the Disability Rating Index showed a non-significant deterioration. The qualitative analysis uncovered one overarching theme and four themes for the patients and three themes for the physical therapist. Conclusions The exercise therapy intervention seems to be feasible with favorable outcomes for the patients. The quantitative and qualitative analyses demonstrated exercise therapy to be beneficial from several different perspectives. However, although structured, the training needs customization and individual adaption from a clinical reasoning perspective in order to meet each patient's individual needs. Implications This study shows that supervised gym-based exercise therapy is feasible for patients with severe, persistent neck pain. It facilitates and motivates the execution of a larger, controlled trial, which might then lead to a new and potentially effective addition to the toolbox of all health care providers treating patients with persistent neck pain.

Acceptance: a factor to consider in persistent pain after neck trauma.

BACKGROUND AND AIMS: Studies on the interaction between acceptance and pain-related processes after neck trauma are to our knowledge sparse and such treatment strategies are rarely incorporated in management and treatment of posttraumatic neck pain. Thus, the aim of the present study is to investigate how acceptance relates to persistent pain in patients after neck trauma, when controlling for the influence of other psychological factors, trauma characteristics and demographic variables. METHODS: Consecutive patients with persistent pain and disability after neck trauma (n = 565) were assessed by a multi-professional team at a specialized pain rehabilitation clinic. Separate regression analyses were conducted with three outcomes: pain distribution, pain interference, and pain severity. Predictors were age, sex, education, time since trauma, type of trauma, anxiety, depression, and acceptance. RESULTS: Acceptance was the only factor associated with all outcomes, and patients with lower acceptance displayed more widespread pain and greater interference and severity of pain. The results also showed that higher depression was associated with worse pain interference and severity, whilst anxiety only mattered significantly for pain severity and not for pain interference. Female sex was related to more widespread pain and greater pain interference. CONCLUSIONS: Overall acceptance stood out as the most important factor for the different outcomes and lower acceptance was associated with more widespread pain distribution and greater pain interference and severity. IMPLICATIONS: The findings of this study add to a growing body of literature confirming that the development of chronicity after neck trauma should be understood as a multidimensional process, best described by a biopsychosocial model. The results also suggest that psychological factors and especially acceptance might be important processes with implications for enhanced recovery after neck trauma.

Recommendations For Core Outcome Domain Set For Whiplash-Associated Disorders (CATWAD).

OBJECTIVE: Inconsistent reporting of outcomes in clinical trials of treatments for Whiplash-associated Disorders (WAD) hinders effective data pooling and conclusions that can be drawn about the effectiveness of tested treatments. The aim of this study was to provide recommendations for core outcome domains that should be included in clinical trials of WAD. MATERIALS AND METHODS: A 3-step process was used: (1) A list of potential core outcome domains were identified from the published literature. (2) Researchers, health care providers, patients, and insurance personnel participated and rated the importance of each domain via a 3-round Delphi survey. A priori criteria for consensus were established. (3) Experts comprising researchers, health care providers, and a consumer representative participated in a multidisciplinary consensus meeting that made final decisions on the recommended core outcome domains. RESULTS: The literature search identified 63 potential core domains. A total of 223 participants were invited to partake in the Delphi surveys, with 41.7% completing round 1, 45.3% round 2, and 51.4% round 3. Eleven core domains met the criteria for inclusion across the entire sample. After the expert consensus meeting, 6 core domains were recommended: Physical Functioning, Perceived Recovery, Work and Social Functioning, Psychological Functioning, Quality of Life, and Pain. DISCUSSION: A 3-step process was used to recommend core outcome domains for clinical trials in WAD. Six core domains were recommended: Physical Functioning, Perceived Recovery, Work and Social Functioning, Psychological Functioning, Quality of Life, and Pain. The next step is to determine the outcome measurement instruments for each of these domains.

Pain and Pain Medication among Older People with Intellectual Disabilities in Comparison with the General Population.

Little is known about pain and pain treatment among people with intellectual disabilities (IDs). We aimed to describe pain and pain medications among older people with ID compared to the general population. Data on diagnoses and prescriptions were collected from national registers for the period between 2006 and 2012 for 7936 people with an ID and a referent cohort from the general population. IDs were associated with a decreased risk of being diagnosed with headaches, musculoskeletal pain, and pain related to the circulatory and respiratory systems, but they were associated with increased risk of being diagnosed with pain related to the urinary system. Among men, IDs were associated with an increased risk of being diagnosed with visceral pain. People with IDs were more likely to be prescribed paracetamol and fentanyl regardless of the type of pain but were less likely to be prescribed COX(1+2) and COX2 inhibitors and weak opioids. Healthcare staff and caregivers must be made aware of signs of pain among people with IDs who may not be able to communicate it themselves. Further research is needed to investigate whether people with IDs are prescribed paracetamol rather than other pain drugs due to physicians trying to avoid polypharmacy or if there are other reasons not to prescribe a greater range of pain treatments.

Spectroscopic differences in posterior insula in patients with chronic temporomandibular pain.

Background and aims Chronic pain including temporomandibular disorder (TMD) pain involves a complex interplay between peripheral and central sensitization, endogenous modulatory pathways, cortical processing and integration and numerous psychological, behavioral and social factors. The aim of this study was to compare spectroscopic patterns of N-Acetyl-aspartate (NAA), total creatine (tCr), choline (Cho), myo-inositol (MI), glutamate (Glu), and the combination of Glu and glutamine in the posterior insula in patients with chronic generalized or regional chronic TMD pain (gTMD and rTMD, respectively) compared to healthy individuals (HI) in relation to clinical findings of TMD pain. Methods Thirty-six female patients with chronic rTMD or gTMD with at least 3 months duration were included in the study. Ten healthy women were included as controls. All participants completed a questionnaire that comprised assessment of degrees of depression, anxiety, stress, catastrophizing, pain intensity, disability and locations. A clinical Diagnostic Criteria for Temporomandibular Disorders examination that comprised assessment of pain locations, headache, mouth opening capacity, pain on mandibular movement, pain on palpation and temporomandibular joint noises was performed. Pressure-pain threshold (PPT) over the masseter muscle and temporal summation to pressure stimuli were assessed with an algometer. Within a week all participants underwent non-contrast enhanced MRI on a 3T MR scanner assessing T1-w and T2-w fluid attenuation inversion recovery. A single-voxel 1H-MRS examination using point-resolved spectroscopy was performed. The metabolite concentrations of NAA, tCr, Cho, MI, Glu and Glx were analyzed with the LC model. Metabolite levels were calculated as absolute concentrations, normalized to the water signal. Metabolite concentrations were used for statistical analysis from the LC model if the Cramér-Rao bounds were less than 20%. In addition, the ratios NAA/tCr, Cho/tCr, Glu/tCr and MI/tCr were calculated. Results The results showed significantly higher tCr levels within the posterior insula in patients with rTMD or gTMD pain than in HI (p=0.029). Cho was negatively correlated to maximum mouth opening capacity with or without pain (rs=-0.42, n=28, p=0.031 and rs=-0.48, n=28, p=0.034, respectively) as well as pressure-pain threshold on the hand (rs=-0.41, n=28, p=0.031). Glu was positively correlated to temporal summation to painful mechanical stimuli (rs=0.42, n=26, p=0.034). Conclusions The present study found that increased concentrations of Cho and Glu in the posterior insular cortex is related to clinical characteristics of chronic TMD pain, including generalized pain. These findings provide new evidence about the critical involvement of the posterior insular cortex and the neurobiology underlying TMD pain in both regional and generalized manifestations. Implications The findings in this study have indirect implications for the diagnosis and management of TMD patients. That said, the findings provide new evidence about the critical involvement of the posterior insular cortex and the neurobiology underlying TMD pain in both regional and generalized manifestations. It is also a further step towards understanding and accepting chronic pain as a disorder in itself.

Sex-based differences in pain distribution in a cohort of patients with persistent post-traumatic neck pain.

OBJECTIVES: To analyze a cohort of 745 consecutive patients referred to a regional specialist clinic for evaluation of post-traumatic neck pain during a five-year period. METHODS: A cross-sectional observational study of baseline assessments performed by multi-professional rehabilitation teams according to a standardized checklist. RESULTS: The cohort contained nearly twice as many females as males (64% versus 36%). The type of injury did not differ between sexes. Of the entire cohort, 38% were diagnosed with widespread pain, 50% with regional pain, and 12% with local pain. The pain distribution among the females was 43% widespread, 48% regional, and 9% local, and corresponding figures among males were 29%, 53%, and 18%. Longer time between trauma and assessment did not affect pain distribution among the men, but a tendency towards more widespread pain was observed among the women. DISCUSSION: The importance of "female sex" as risk factor for the development of persistent pain after neck trauma needs to be discussed further. The high frequency of regional and widespread pain among patients with persistent neck pain after trauma calls for both multidisciplinary assessments and treatment strategies. The relationships between different pain distribution patterns, disability, activity, and psychological factors need to be studied further. Implications for rehabilitation Patients suffering from pain and disability after neck trauma constitute a significant proportion of patients with persistent pain. The importance of the risk factor "female sex" should be further discussed in the development of persistent pain after neck trauma. The high frequency of regional and widespread pain among patients with persistent neck pain after trauma calls both for multidisciplinary assessments and treatment strategies. The relationships between different pain distribution patterns, disability, activity, and psychological factors need to be studied further.

Quantitative sensory testing of temperature thresholds: Possible biomarkers for persistent pain?

OBJECTIVE: To investigate the reproducibility of thermal thresholds, as measured by repeated quantitative sensory testing (QST) in healthy controls, and to asses if temperature sensitivity differs between healthy controls and a cohort of patients with persistent pain. SUBJECTS: A total of 54 healthy controls were compared with 25 consecutive patients selected for pain rehabilitation by multidisciplinary assessment teams. METHODS: Heat and cold detection and pain thresholds in the forearm and neck were determined by QST. Reproducibility was evaluated by 2 consecutive tests 6-9 months apart. RESULTS: Thermal detection and pain thresholds were reproducible in a subgroup of 20 healthy controls. The patients had slightly increased heat and cold detection thresholds, but significantly lower thresholds for cold and heat pain. The most clear-cut differences between patients and healthy controls were observed for cold pain thresholds. Calculation of the differences between thermal detection and pain thresholds (delta values) further strengthened the differences between patients and healthy controls. CONCLUSION: Thermal detection and pain thresholds are reproducible over time, allowing longitudinal assessment of sensory function using QST. Although increased sensitivity to cold pain was the most prominent finding in this cohort of patients with persistent pain, calculation of the differences between thermal detection and pain thresholds may prove superior in detecting sensory alterations.

Somatosensory impairments are common after stroke but have only a small impact on post-stroke shoulder pain.

OBJECTIVE: To investigate whether somatosensory impairments are more common in individuals with post-stroke shoulder pain than in those without post-stroke shoulder pain and healthy controls. DESIGN: Descriptive analysis of a convenience sample. PARTICIPANTS: Forty-nine individuals with stroke, 24 with and 25 without post-stroke shoulder pain (median age 65 years), and 11 age- and sex-matched healthy controls. METHODS: Perception and pain thresholds for cold, warm and heat (thermal thresholds), and pain thresholds for pressure and pin prick (mechanical thresholds) were assessed using quantitative sensory testing (QST). Passive range of motion, motor function, resistance to passive movements, light touch and proprioception were assessed in the upper extremities. Shoulder pain characteristics were recorded in the post-stroke shoulder pain group. RESULTS: There were no significant differences between the group with post-stroke shoulder pain and the group without post-stroke shoulder pain in any of the QST assessments, but more participants in the post-stroke shoulder pain group reported abnormal cold sensation in the affected side. Both stroke groups had generally higher thermal thresholds and more extreme low or high mechanical thresholds than the healthy controls. CONCLUSION: Somatosensory impairments are common among individuals with stroke compared with healthy controls. The non-significant differences in QST thresholds between the group with post-stroke shoulder pain and the group without post-stroke shoulder pain indicate that somatosensory impairments have only a small impact on post-stroke shoulder pain.

Healthcare consultation and sick leave before and after neck injury: a cohort study with matched population-based references.

OBJECTIVES: Recent studies based on self-assessed data on exposure and outcome suggest a negative association between poor health before neck injury and recovery. Our aim was to study actual healthcare consultation and work disability before and after neck injury (whiplash). DESIGN: Cohort study with matched references studied prospectively and retrospectively via regional and national held registers. SETTING: Population-based study in Region Skåne, Sweden (population=1.21 million) including all levels of healthcare. PARTICIPANTS: 1443 participants aged ≥18 (54% women) with acute neck injury, Whiplash, (International Classification of Diseases-10-SE code S13.4*) in 2007 or 2008 and no such diagnosis since 1998. Each patient with a neck injury was assigned four randomly selected population references matched for age, sex and area of residence (97% of the patients and 94% of the references were followed during the whole study period). PRIMARY AND SECONDARY OUTCOME MEASURES: We studied changes in healthcare consultations 3 years before to 3 years after diagnosis as well as sick leave episodes. Analyses were also stratified by preinjury frequency of consultation. RESULTS: Before the injury, the mean number of total consultations over 36 months among the neck injured (n=1443) and references (n=5772) was 9.3 vs 7.2 (p<0.0001) and postneck injury 12.7 vs 7.8 (p<0.0001). In the group of high-frequent consulters, there were more women compared with frequent and low-frequent consulters (70.6% vs 32.8%; p<0.0001). Among low-frequent and frequent consulters preinjury (n=967, 67% of the cohort), 16% became high-frequent consulters attributable to the injury. The number of days of sick leave preinjury was correlated with the number of preinjury and postinjury consultations (r=0.47 (99% CI 0.38 to 0.49), r=0.32 (99% CI 0.25 to 0.37)). CONCLUSIONS: People with a neck injury constitute a heterogeneous group. The preinjury level of healthcare consultation is associated with the postinjury level of consultation.

Temporomandibular disorder pain after whiplash trauma: a systematic review.

AIMS: To assess, by systematic review of the literature, (1) the prevalence and incidence of temporomandibular disorder (TMD) pain after whiplash trauma, and (2) whether treatment modalities commonly used for TMD are equally effective in patients with solely TMD pain and those with TMD/whiplash-associated disorders (WAD) pain. METHODS: A systematic literature search of the PubMed, Cochrane Library, and Bandolier databases was conducted from January 1966 through October 2012. The systematic search identified 125 articles. After an initial screening of abstracts, 45 articles were reviewed in full text. Two investigators evaluated the methodological quality of each identified study. RESULTS: Eight studies on prevalence/incidence of TMD pain in WAD and four studies on interventions in TMD pain and WAD met the inclusion criteria. The reported median prevalence of TMD pain after whiplash trauma was 23% (range 2.4% to 52%) and the incidence ranged from 4% to 34%. For healthy controls, the reported median prevalence was 3% (range 2.5% to 8%) and the incidence ranged from 4.7% to 7%. For patients with a combination of TMD pain and WAD, treatment modalities conventionally used for TMD, such as jaw exercises and occlusal splints, had less of an effect (median improvement rate of 48%, range 13% to 68%) compared to TMD patients without a whiplash injury (75%, range 51% to 91%). CONCLUSION: There is some evidence that prevalence and incidence of TMD pain is increased after whiplash trauma. The poorer treatment outcome suggests that TMD pain after whiplash trauma has a different pathophysiology compared to TMD pain localized to the facial region.

Experimentally induced deep cervical muscle pain distorts head on trunk orientation.

PURPOSE: We wanted to explore the specific proprioceptive effect of cervical pain on sensorimotor control. Sensorimotor control comprises proprioceptive feedback, central integration and subsequent muscular response. Pain might be one cause of previously reported disturbances in joint kinematics, head on trunk orientation and postural control. However, the causal relationship between the impact of cervical pain on proprioception and thus on sensorimotor control has to be established. METHODS: Eleven healthy subjects were examined in their ability to reproduce two different head on trunk targets, neutral head position (NHP) and 30° target position, with a 3D motion analyser before, directly after and 15 min after experimentally induced neck pain. Pain was induced by hypertonic saline infusion at C2/3 level in the splenius capitis muscle on one side (referred to as "injected side"). RESULTS: All subjects experienced temporary pain and the head repositioning error increased significantly during head repositioning to the 30° target to the injected side (p = 0.011). A post hoc analysis showed that pain interfered with proprioception to the injected side during acute pain (p < 0.001), but also when the pain had waned (p = 0.002). Accuracy decreased immediately after pain induction for the 30° target position to the side where pain was induced (3.3 â†’ 5.3°, p = 0.033), but not to the contralateral side (4.9 â†’ 4.1°, p = 0.657). There was no significant impact of pain on accuracy for NHP. A sensory mismatch appeared in some subjects, who experienced dizziness. CONCLUSIONS: Acute cervical pain distorts sensorimotor control with side-specific changes, but also has more complex effects that appear when pain has waned.

Treatment of post-traumatic pain, and autonomic and muscular dysfunction by ganglion impar block and medial branch block of the facet joints: A case report.

Introduction Patients exposed to whiplash trauma are at risk of developing pain and dysfunction of the neck and shoulder. Although rarely discussed in the literature, some patients also develop autonomic dysfunction. Case presentation A previously healthy 41-year-old woman was involved in a "head-on" car crash. During the following 3 years she developed severe and complex post-traumatic pain syndrome, which consisted of neck pain, lumbar pain, sensory-motor dysfunction, and myoclonic muscular contractions. Despite pharmacotherapy, physiotherapy, and rehabilitation, her condition worsened, resulting in severe disability. Fourteen years after the car crash, an interventional pain therapy program was started, which consisted of sympathetic ganglion impar block and medial branch blocks of facet joints at different levels. These treatment strategies ultimately normalized her sensory-motor dysfunction, reduced her autonomic dysfunction, and stopped the myoclonic muscular contractions. Conclusion This case highlights a possible interaction between the pain-generating facet joints, the somatosensory nervous system, and the autonomic/sympathetic nervous systems. The case also highlights the importance of identifying autonomic dysfunction in patients with persisting pain syndromes. Implications This complex case shows that many clinical phenomena cannot be explained using our present knowledge of pain mechanisms. We hope that readers who have observed similar cases can learn from our case, and are encouraged to publish their observations.