IL-6 from cerebrospinal fluid causes widespread pain via STAT3-mediated astrocytosis in chronic constriction injury of the infraorbital nerve

BACKGROUND

The spinal inflammatory signal often spreads to distant segments, accompanied by widespread pain symptom under neuropathological conditions. Multiple cytokines are released into the cerebrospinal fluid (CSF), potentially inducing the activation of an inflammatory cascade at remote segments through CSF flow. However, the detailed alteration of CSF in neuropathic pain and its specific role in widespread pain remain obscure.

METHODS

A chronic constriction injury of the infraorbital nerve (CCI-ION) model was constructed, and pain-related behavior was observed on the 7th, 14th, 21st, and 28th days post surgery, in both vibrissa pads and hind paws. CSF from CCI-ION rats was transplanted to naïve rats through intracisternal injection, and thermal and mechanical allodynia were measured in hind paws. The alteration of inflammatory cytokines in CCI-ION's CSF was detected using an antibody array and bioinformatic analysis. Pharmacological intervention targeting the changed cytokine in the CSF and downstream signaling was performed to evaluate its role in widespread pain.

RESULTS

CCI-ION induced local pain in vibrissa pads together with widespread pain in hind paws. CCI-ION's CSF transplantation, compared with sham CSF, contributed to vibrissa pad pain and hind paw pain in recipient rats. Among the measured cytokines, interleukin-6 (IL-6) and leptin were increased in CCI-ION's CSF, while interleukin-13 (IL-13) was significantly reduced. Furthermore, the concentration of CSF IL-6 was correlated with nerve injury extent, which gated the occurrence of widespread pain. Both astrocytes and microglia were increased in remote segments of the CCI-ION model, while the inhibition of astrocytes in remote segments, but not microglia, significantly alleviated widespread pain. Mechanically, astroglial signal transducer and activator of transcription 3 (STAT3) in remote segments were activated by CSF IL-6, the inhibition of which significantly mitigated widespread pain in CCI-ION.

CONCLUSION

IL-6 was induced in the CSF of the CCI-ION model, triggering widespread pain via activating astrocyte STAT3 signal in remote segments. Therapies targeting IL-6/STAT3 signaling might serve as a promising strategy for the widespread pain symptom under neuropathological conditions.

Instrumental assessment of pressure pain threshold over trigeminal and extra-trigeminal area in people with episodic and chronic migraine: a cross-sectional observational study

BACKGROUND

Central and peripheral sensitization are characterized by widespread hyperalgesia that is manifested by larger pain extent area and reduction in pressure pain threshold (PPT). PPT decreases in patients with migraine not only over the trigeminal cervical complex but also throughout the body.

METHODS

A cross-sectional study was adopted to assess the local and widespread hyperalgesia in chronic and episodic migraine patients respect to healthy controls. The guidelines of Andersen's were used to evaluate the PPT bilaterally over 3 muscles in the trigemino-cervical complex (temporalis, sub-occipitalis, trapezius) and over 1 muscle far from this area (tensor fasciae latae).

RESULTS

Thirty subjects with episodic migraine (35.8 ± 2.82 years), 30 with chronic migraine (53.03 ± 19.79 years), and 30 healthy controls (29.06 ± 14.03 years) were enrolled. The interaction effect was present for the trapezius muscle with a significant difference between the right and the left side in episodic group (p = 0.003). A group effect was highlighted in all four muscles analyzed such as suboccipital (p < 0.001), temporalis (p > 0.001), trapezius (p < 0.001), and TFL (p < 0.001). PPT was usually higher in the control group than in the episodic group which in turn was characterized by higher PPT values than the chronic group.

CONCLUSIONS

People with chronic and episodic migraine presented lower PPT than healthy controls both in the trigeminal and in the extra-trigeminal area. People with chronic migraine presented lower PPT than episodic migraine only in the trigeminal area. Temporalis and sub-occipitalis are the most sensitive muscles in people with chronic and episodic migraine.

Diagnostic difficulty, delayed diagnosis, and increased tendencies of surgical treatment in fibromyalgia syndrome

PURPOSE

Aimed to evaluate the time elapsed between the onset of early symptoms and the diagnosis of fibromyalgia syndrome (FMS), the delays in diagnosis and frequent physician visits, increased tendencies of surgical treatment, and the effects of FMS symptoms on the post-surgical result.

PATIENTS AND METHODS

While there were 101 patients diagnosed with FMS in the 1st group, there were 100 patients in the 2nd group who presented with musculoskeletal complaints but were not diagnosed with FMS. In both groups, information on duration of complaints, time until diagnosis, and number of evaluating physicians were included. They were questioned in terms of whether they had undergone elective surgery before and after FMS diagnosis, and in terms of operation sites. Among these operations, the ones regarding the musculoskeletal system were evaluated, and the preoperative and postoperative, before and after FMS diagnosis.

RESULTS

It was determined that the diagnosis of FMS was made late; the number of doctor visits increased in the period until the diagnosis, and the rate of surgical treatment was higher than in patients without FMS. It was determined that the patients who were operated on after being diagnosed with FMS gained from the operation while the rate of gaining from surgery was lower in patients with FMS symptoms who were operated on before the diagnosis was made.

CONCLUSION

The diagnosis of FMS reduces healthcare use, including referrals and examinations. Educating clinicians in the recognition and diagnosis of FMS will provide both patients and healthcare providers with benefits. Key Points • Early detection of FMS reduces healthcare utilization and expenditure, including referrals and examinations. • Educating clinicians in the recognition and diagnosis of FMS will provide both patients and healthcare providers with benefits. Therefore, it is important to understand why the diagnosis of FMS is made in a delayed manner. • Providing pragmatic tools to improve the methodology of primary care providers may help with diagnosing FMS accurately. • Early diagnosis and treatment of FMS may lead to a decrease in the number of operations and an improvement in the results of the operation.

Fibromyalgia syndrome - a risk factor for poor outcomes following orthopaedic surgery: A systematic review

BACKGROUND

Fibromyalgia (FM) is a complex syndrome incorporating many features associated with poor outcome in orthopaedic surgery. Aim of the present review was to comprehensively characterize the available evidence on the consequences of pre-existent FM on the outcomes of orthopaedic surgery.

METHODS

We performed a systematic search in MedLine and Web of Science (WOS) to identify studies evaluating the effect of FM on patient-centred outcomes, opioids consumption and postoperative complications.

RESULTS

The search strategy identified 519 records in PubMed and 507 in WOS. A total of 27 articles were deemed eligible for inclusion in qualitative synthesis. Based on quality assessment, 10 studies were rated as good quality, 10 as fair quality and 7 as poor quality. Studies reporting the prevalence of FM in consecutive patients undergoing orthopaedic surgery (n = 19) were included in quantitative synthesis. The pooled prevalence of FM in patients undergoing orthopaedic surgery was 4.1% (95% CI: 2.4-6.8) in those receiving hip or knee surgery, 10.1% (95% CI: 5.7-17.2) in those receiving shoulder or elbow surgery and 21.0% (95% CI: 18.5-23.7) in those receiving spinal surgery. The results of our systematic review consistently report FM as a significant risk factor for less satisfaction, higher pain, worse functional outcome, increased risk for postoperative opioids prescription and higher rate of medical and surgical complications following orthopaedic surgery.

CONCLUSION

Identifying pre-existing FM in patients scheduled for elective orthopaedic surgery may help to better assess the benefit/risk ratio, improve patients' awareness and minimize any discrepancy between expectancy and results.

The spectrum of pediatric amplified musculoskeletal pain syndrome

BACKGROUND

Children presenting with musculoskeletal pain to pediatric rheumatology clinics are very heterogeneous and on a continuum from those with localized pain to total body pain. Many report intermittent, rather than constant, pain. We examined clinical and psychological characteristics of these children at presentation and specifically those who fulfilled the criteria for fibromyalgia.

METHODS

We performed a retrospective, cross-sectional cohort study of children under ≤18 years old presenting to the pediatric rheumatology pain clinic between January 2015 and July 2019 and enrolled in a patient registry. We included children diagnosed with amplified pain, excluding those fulfilling criteria for complex regional pain syndrome. Abstracted data included clinical characteristics, pain symptoms, functional disability inventory (FDI), widespread pain index, and symptom severity scale.

RESULTS

We analyzed 636 subjects, predominantly non-Hispanic Caucasian females. Using median split method, 54% had diffuse pain (≥ 5 body regions involved), but, of these, only 58% met criteria for fibromyalgia. Subjects with diffuse pain, compared to those with localized pain had a longer duration of pain (24 vs 12 months, p < 0.01), reported greater pain intensity (6/10 vs 5/10, p < 0.001), greater mental health burden, and poorer function (FDI 25 vs 19, p < 0.0001). Subjects with limited pain more often reported a history of trigger event (34% vs 24%, p < 0.01) but not autonomic changes (14% vs 14%, p = 0.94). The presence of adverse childhood experiences did not differ among those with limited versus diffuse pain except for parental divorce (16% vs 23%, p = 0.03). Intermittent pain was reported in 117 children (18%) and, compared to subjects with constant pain, they reported less pain (0/10 vs 6/10) and were more functional (FDI 13 vs 25) (both p < 0.0001).

CONCLUSIONS

There exists a wide spectrum of pain manifestations among children with amplified pain including limited or diffuse and constant or intermittent pain. Most children who presented to our clinic did not fulfill criteria for fibromyalgia but nonetheless had significant symptoms and disability. Studies focusing on fibromyalgia may miss the full extent of childhood amplified pain. Additionally, research limited to those meeting the fibromyalgia criteria likely underestimate the significant impact of amplified pain among the pediatric population.

Widespread pain is a risk factor for cardiovascular mortality: results from the Framingham Heart Study

AIMS

With the introduction of widespread pain (WSP) as a separate diagnostic code in the ICD-11, WSP has now become an own clinical diagnosis independent of the underlying pathophysiology. Research has reported aetiological associations of WSP and cardiovascular diseases. However, studies on mortality risk in individuals with WSP have reported inconsistent results. This study investigates whether there is increased mortality in WSP individuals and establish potential determinants of mortality risk. Therefore, we evaluates the population-based prospective cohort of the Framingham Heart Study (FHS).

METHODS AND RESULTS

The FHS is a longitudinal multi-generational study. Pain status was assessed uniquely between 1990 and 1994. Cox proportional hazards modelling was used to estimate hazard ratios (HRs) of WSP on all-cause mortality controlling for sex and age, cardiovascular risk factors, cancer history, lifestyle factors and current medication. WSP examination was carried out in 4746 participants of the FHS (60.3 ± 13.5 years, 55.1% women). A total of 678 (14.5%) subjects fulfilled the criteria for WSP, whereas 4011 (85.5%) subjects did not. The follow-up time was 15 years, during which 202 persons died in the WSP group and 1144 in the no-WSP group. When adjusting for age and sex, all-cause mortality was increased by about 16% in WSP subjects. Individuals with WSP had an increased HR particularly for cardiovascular cause of death (HR adjusted by age and sex = 1.46, 95% confidence interval 1.10-1.94).

CONCLUSION

Our data show that in a large population-based cohort, WSP is associated with increased HR for cardiovascular cause of death, underlining the need for pain assessments in cardiovascular practice.

The therapeutic efficacy of Qigong exercise on the main symptoms of fibromyalgia: A pilot randomized clinical trial

Background

Some of the most debilitating symptoms of fibromyalgia (FM) include widespread chronic pain, sleep disturbances, chronic fatigue, anxiety, and depression. Yet, there is a lack of effective self-management exercise interventions capable of alleviating FM symptoms. The objective of this study is to examine the efficacy of a 10-week daily Qigong, a mind–body intervention program, on FM symptoms.

Methods

20 participants with FM were randomly assigned to Qigong (experimental) or sham-Qigong (control) groups, with participants blinded to the intervention allocation. The Qigong group practiced mild body movements synchronized with deep diaphragmatic breathing and meditation. The sham-Qigong group practiced only mild body movements. Both groups practiced the interventions two times per day at home, plus one weekly group practice session with a Qigong instructor. Primary outcomes were: pain changes measured by the Short-Form McGill Pain Questionnaire, a visual analog scale for pain, pressure pain threshold measured by a dolorimeter. Secondary outcomes were: the Revised Fibromyalgia Impact Questionnaire the Pittsburgh Sleep Quality Index, the Hospital Anxiety and Depression Scale and the Quality of Life Scale.

Results

The experimental group experienced greater clinical improvements when compared to the control group on the mean score differences of pain, sleep quality, chronic fatigue, anxiety, depression, and fibromyalgia impact, all being statistically significant at p < 0.05.

Conclusion

Daily practice of Qigong appears to have a positive impact on the main fibromyalgia symptoms that is beyond group interaction.

Trial registration

ClinicalTrials.gov NCT03441997.

All-cause and cause-specific mortality in persons with fibromyalgia and widespread pain: An observational study in 35,248 persons with rheumatoid arthritis, non-inflammatory rheumatic disorders and clinical fibromyalgia

PURPOSE

Studies of the relation of fibromyalgia (FM) and widespread pain (WSP) to mortality have differed as to the presence or absence of an association and the extent of cause-specific mortality. However, no studies have investigated which definitions of FM and WSP associate with mortality, nor of FM mortality in other diseases. We investigated these issues and the meaning of mortality in patients with FM.

METHODS

We used Cox regression to study 35,248 rheumatic disease patients with up to 16 years of mortality follow-up in all patients and separately in those with diagnoses of rheumatoid arthritis (RA) (N = 26,458), non-inflammatory rheumatic disorders (NIRMD) (N = 5,167) and clinically diagnosed FM (N = 3,659). We applied 2016 FM criteria and other FM and WSP criteria to models adjusted for age and sex as well as to models that included a full range of covariates, including comorbid disease and functional status. We estimated the degree of explained of variance (R2) as a measure of predictive ability.

RESULTS

We found positive associations between al`l definitions of FM and WSP and all-cause mortality, with relative risks (RR)s ranging from 1.19 (95%CI 1.15-1.24) for American College of Rheumatology (ACR) 1990 WSP to 1.38 (1.31-1.46) in age and sex adjusted revised 2016 criteria (FM 2016). However, in full covariate models the FM 2016 RR reduced further to 1.15 (1.09-1.22). The association with mortality was noted with RA (1.52 (1.43-1.61)), NIRMD (1.43 (1.24-1.66)) and clinical FM (1.41 (1.14-1.75) - where 37% of FM diagnosed patients did not satisfy FM 2016 criteria. In the all-patient analyses, the age and sex explained variation (R2) was 0.255, increasing to 0.264 (4.4%) when FM 2016 criteria were added, and to 0.378 in a full covariate model. Death causes related to FM 2016 status included accidents, 1.45 (1.11-1.91); diabetes 1.78 (1.16-2,71); suicide, 3.01 (1.55-5.84) and hypertensive related disorders, 3.01 (1.55-5.84). Cancer deaths were less common 0.77 (0.68-0.88).

CONCLUSIONS

FM is weakly associated with mortality within all criteria definitions of FM and WSP examined (3.4% of explained variance), and across all diseases (RA, NIRMD, clinical FM) equally. Clinical and criteria-defined FM had different mortality outcomes. We found no evidence for a positive association of cancer and FM or WSP.

Comparing the association of widespread pain, multi-joint pain and low back pain with measures of pain sensitization and function in people with knee osteoarthritis

INTRODUCTION/OBJECTIVES

To compare 1. measures of pain sensitization (PS) in people with widespread pain (WSP), multi-joint pain, low back pain (LBP) and knee osteoarthritis (KOA) only, in people with knee OA and 2. results of self-reported function and physical performance tests amongst these sub groups.

METHODOLOGY

Patients with knee OA consulting an orthopaedic surgeon were recruited from three Montreal area hospitals. A body homunculus was used to identify the presence of WSP (Y/N), multi-joint pain using a joint count (≥ 2 joints) and LBP (Y/N). Tests included pressure pain thresholds (PPT), temporal summation (TS), conditioned pain modulation and three physical performance tests. The Knee Injury and Osteoarthritis Outcome Score (KOOS) assessed self-reported function. Means were compared with Welch's ANOVA, post hoc tests and multiple regression analysis were performed.

RESULTS

Two hundred twenty-one participants were evaluated (mean age: 63.4 ± 9.9 years, females n = 135 (61.1%)). Those with WSP significantly differed from those with LBP on PPT mean - 1.4, 95%CI (- 2.4, - 0.4), TS 10.3 (2.1, 18.5) and the stair climb test (SCT) 5.6 (1.3, 9.9). Those with WSP significantly differed from those with KOA only on TS 9.5 (1.0, 18.1), SCT 6.3 (2.0, 10.6) and KOOS - 14.2 (- 26.5, - 2.0).

CONCLUSION

In patients with knee OA, those with WSP demonstrated greater degrees of PS compared with those with knee OA only, LBP and multi-joint pain. They also demonstrated a slower SCT compared with those with KOA only and LBP and decreased self-reported function compared with those with KOA only. These results should be confirmed in a longitudinal study.Key Points• In people with knee OA and widespread pain, measures of sensitization, self-reported function and physical performance were poorer compared with those with knee OA and LBP, knee OA and multi-joint pain or knee OA only.• Clinicians can consider these outcomes when planning management for these subgroups planning a comprehensive treatment program for this subgroup.

Perceived helpfulness of treatments for myofascial TMD as a function of comorbid widespread pain

OBJECTIVE

This study examined whether patients with myofascial temporomandibular disorder (mTMD) comorbid with fibromyalgia (FM) receive different treatments or respond differently to these treatments than mTMD-only patients.

MATERIALS AND METHODS

A total of 125 mTMD+ women were enrolled (26 FM+ and 98 FM-). mTMD and FM were assessed via clinical research examinations. Treatment histories and self-reported treatment-related improvement were obtained via interview.

RESULTS

The top 3 most common treatments reported were oral appliances (59%), physical therapy (54%), and jaw exercises at home (34%). Use of alternative medicine was reported more frequently among FM+ women, but self-reported improvement did not differ by comorbid FM. Physical therapy was as likely reported by FM status but self-reported improvement scores trended higher for FM+ women.

CONCLUSIONS

Oral appliances were as likely to be reported by FM comorbid as FM- women. Oral appliances did not outperform self-management treatments on self-reported improvement of facial pain.

CLINICAL RELEVANCE

Results support the use of self-management as first-line treatment for mTMD and potential utility of inquiring about widespread pain for treatment planning.

High-frequency spinal cord stimulation at 10 kHz for widespread pain: a retrospective survey of outcomes from combined cervical and thoracic electrode placements

OBJECTIVE

To report on the long-term outcomes for patients receiving paraesthesia-free high-frequency spinal cord stimulation (HF10-SCS) at 10 kHz for the treatment of combined upper and lower body neuropathic/nociplastic pain syndromes including chronic widespread pain/fibromyalgia.

MATERIALS AND METHODS

Forty-five patients with widespread (both upper and lower body) neuropathic/nociplastic pain syndromes underwent a trial of combined cervical and thoracic HF10-SCS leads placed over the C2/T2 or C2/T9 vertebral levels, or three leads placed over the C2/T2/T9 vertebral levels. Thirty-eight patients proceeded to permanent implant, resulting in a trial to implant conversion rate of 84.4%. Patients were followed up an average of 2.3 ± 1.7 years post-permanent implant. Patient outcomes were recorded.

RESULTS

A statistically significant reduction of 3.5 ± 1.6 on the 10-point numerical rating scale (NRS) at 2.3 ± 1.7 years post-permanent implant was observed (baseline: 7.1 ± 0.8 vs. follow up: 3.7 ± 1.3) (p ≤ 001). Likewise, a reduction in disability (Roland Morris Disability Questionnaire) was also observed; baseline: 12.3 ± 5.1 vs. follow up: 7.8 ± 5.9. Similar trends were observed in a working capacity, with 20/31 (64.5%) of the work eligible patients employed at follow-up, compared with only 8/31 (25.8%) at baseline. Opioid pain medication use reduced and over 90% of patients were satisfied with their treatment outcome. No long-term adverse events were observed.

CONCLUSIONS

HF10-SCS at 10 kHz provides long-term widespread pain relief when leads are staggered across the cervical and thoracic spine. The improved return to work outcomes and opiate reductions suggest that cost-effectiveness as well as clinical effectiveness may be achieved with this treatment approach.

Widespread pain in axial spondyloarthritis: clinical importance and gender differences

Background

There is a remarkable lack of detailed knowledge on pain areas in axial spondyloarthritis (axSpA), and their clinical relevance is largely unknown. Pain area may reflect local disease processes, but amplification of nervous system signalling may alter this relationship. Also, gender differences in pain area may exist in axSpA, possibly confounding disease activity outcomes. Therefore, we firstly detailed pain locations in axSpA and evaluated gender differences. Secondly, we explored the relationship of regional pain definitions with clinical outcomes. Finally, we explored the role of pain area in the assessment of disease activity.

Methods

Body charts informed on the presence of axial, peripheral articular and non-articular pain in 170 patients (108 men, 62 women) with axSpA. Multivariate Odds Ratios (ORs) were used to compare genders. General linear models were used to explore clinical differences in disease activity (Bath Ankylosing Spondylitis Disease Activity Index [BASDAI]), activity limitations (Bath Ankylosing Spondylitis Functional Index [BASFI]), fear of movement (Tampa Scale for Kinesiophobia 11-item version [TSK-11]), anxiety (Hospital Anxiety and Depression Scale subscale anxiety [HADS-A]) and depression (HADS subscale depression [HADS-D]) between four subgroups classified by widespread non-articular pain (WNAP+/−) and physician global assessment of disease activity (PGDA+/−) (p < .05). Principal Component Analysis (PCA) was performed to explore gender differences in the structure of disease activity.

Results

Axial thoracic pain was least prevalent (lumbar, 74.4%; cervical, 47.6%; cervicothoracic, 47.6%; thoracic, 32.4%), but it was about three times more likely in women (OR, 2.92; p = .009). Axial cervicothoracic junction pain spread more diffusely in women (OR, 2.48; p = .018). Women exhibited a two- to threefold increased likelihood of widespread axial (OR, 3.33; p = .007) and peripheral articular (OR, 2.34; p = .023) pain. A subgroup of WNAP+/PGDA− combined with low PGDA (27% of all patients) was associated with worse BASFI, BASDAI, HADS-A and HADS-D in men and worse TSK-11 and HADS-A in women (p < .05). Disease activity outcomes showed a two-factor structure in women but not in men.

Conclusions

In patients with axSpA, the location and spread of pain was different between genders and was related to worse clinical status. On the basis of pain area and PGDA, clinical subgroups exhibiting a remarkably distinct health status were identified. Outcome instruments such as BASDAI should acknowledge gender differences to ensure structural validity.

Electronic supplementary material

The online version of this article (10.1186/s13075-018-1626-8) contains supplementary material, which is available to authorized users.

Multigroup latent class model of musculoskeletal pain combinations in children/adolescents: identifying high-risk groups by gender and age

Background

To investigate the combinations of Musculoskeletal pain (MSP) (neck, shoulder, upper and low back pain) among a sample of Iranian school children.

Methods

The MSP combinations was modeled by latent class analysis (LCA) to find the clusters of high–risk individuals and multigroup LCA taking into account the gender and age (≤ 13 years and ≥ 14 years of age categories).

Results

The lowest and highest prevalence of MSP was 14.2% (shoulder pain in boys aged ≥14 years) and 40.4% (low back pain in boys aged ≤13 years), respectively. The likelihood of synchronized neck and low back pain (9.4–17.7%) was highest, while synchronized shoulder and upper back pain (4.5–9.4%) had the lowest probability. The probability of pain at three and four locations was significantly lower in boys aged ≥14 years than in other gender–age categories. The LCA divided the children into minor, moderate, and major pain classes. The likelihood of shoulder and upper back pain in the major pain class was higher in boys than in girls, while the likelihood of neck pain in the moderate pain class and low back pain in the major pain class were higher in children aged ≥14 years than those aged ≤13 years. Gender–age specific clustering indicated a higher likelihood of experiencing major pain in children aged ≤13 years.

Conclusions

The findings highlight the importance of gender– and age–specific data for a more detailed understanding of the MSP combinations in children and adolescents, and identifying high-risk clusters in this regard.

Evidence-Based Non-Pharmacological Therapies for Fibromyalgia

PURPOSE OF REVIEW

Fibromyalgia (FM) is the second most common rheumatologic pain disorder after osteoarthritis with a multisystem presentation. While the treatment of FM in a clinical setting incorporates both pharmacologic and non-pharmacologic modalities, the present investigation reviews evolving literature on cognitive behavioral and complementary medical therapies. The recent medical literature on FM was reviewed between 2012 and 2017 via MEDLINE and the Cochrane Central Registry of Controlled Trials, with an emphasis on randomized controlled trials, meta-analyses, and evidence-based treatment guidelines.

RECENT FINDINGS

Cognitive behavioral therapy continues to play a significant role in the non-medical therapy of FM. It is especially helpful in high catastrophizing patients as evidenced by recent studies that note changes in the brain on functional magnetic resonance imaging. Mindfulness meditation can be helpful in improving pain symptoms and pain perception. No particular diet is found to have a meaningful impact in FM; however, various diets including low fermentable oligo- di -monosaccharides and polyols diet, gluten free, and hypocaloric may be helpful in ameliorating gastrointestinal distress in select patient populations. Current literature does not support the routine use of acupuncture for improving pain or quality of life in FM; however, given its benign side effect profile, it should not be discouraged. Goals for symptom management and pain control should be set early, and patient engagement remains critical in the management of this complex pain presentation. While low quality evidence exists for most non-pharmacologic treatment modalities for FM, CBT and mindfulness meditation show promise for future investigation.

Are the ACR 2010 diagnostic criteria for fibromyalgia better than the 1990 criteria?

Fibromyalgia (FM) is difficult to diagnose and manage chronic pain condition whose symptoms have no clear pathophysiological cause, although it is thought that patient hypersensitivity to a range of stimuli may give rise to mechanical hyperalgesia as a result of altered central nociceptive processing. The 1990 American College of Rheumatology (ACR) classification criteria, which have been widely used in clinical practice, require the existence of chronic widespread pain (CWP) for >3months, and the presence of at least 11 out of 18 specified tender points upon digital palpation, although this latter criterion has long been criticised. The newer 2010 ACR diagnostic criteria state that FM can be defined as CWP associated with somatic symptoms, and recommend the use of a widespread pain index and a scale to rate symptom severity. A modified version of the 2010 criteria removed the physician assessment of the extent of somatic symptoms and replaced it by a summary score of three self-reported symptoms, thus making it easier to use while maintaining its sensitivity. This review discusses the advantages and limitations of all of these criteria.

Prevalence and predictors of persistent pelvic girdle pain 12 years postpartum

BACKGROUND

Pelvic girdle pain (PGP) is not always a self-limiting condition. Women with more pronounced persistent PGP (PPGP) report poorer health status compared to women with less pronounced symptoms. The knowledge concerning the long-term consequences of PPGP is limited, thus more knowledge in this area is needed. The overall aim was to study the prevalence and predictors of PPGP 12 years after delivery.

METHODS

This is a long-term follow-up study based on a previous cohort study that commenced in 2002. New questionnaire data 12 years postpartum were collected in 2014 and early 2015. The questionnaire was distributed to a total of 624 women from the initial cohort.

RESULTS

In total, 295 women (47.3%) responded to the questionnaire where 40.3% (n = 119) reported pain to a various degree and 59% (n = 174) reported no pain. Increased duration and/or persistency of pain, self-rated health, sciatica, neck and/or thoracic spinal pain, sick leave the past 12 months, treatment sought, and prescription and/or non-prescription drugs used were all associated with an statistically significant increase in the odds of reporting pain 12 years postpartum. Widespread pain was common and median expectation of improvement score was 5 on an 11-point numeric scale (interquartile range 2-7.50). More than one of five women (21.8%) reporting pain stated that they had been on sick leave the past 12 months and nearly 11% had been granted disability pension due to PPGP. No statistically significant differences were found between respondents and non-respondents regarding most background variables.

CONCLUSIONS

This study is unique as it is one of few long-term follow-up studies following women with PPGP of more than 11 years. The results show that spontaneous recovery with no recurrences is an unlikely scenario for a subgroup of women with PPGP. Persistency and/or duration of pain symptoms as well as widespread pain appear to be the strongest predictors of poor long-term outcome. Moreover, widespread pain is commonly associated with PPGP and may thus contribute to long-term sick leave and disability pension. A screening tool needs to be developed for the identification of women at risk of developing PPGP to enable early intervention.

The association of pre-operative body pain diagram scores with pain outcomes following total knee arthroplasty

OBJECTIVE

Approximately 20% of total knee arthroplasty (TKA) recipients have suboptimal pain relief. We evaluated the association between pre-surgical widespread body pain and incomplete pain relief following TKA.

METHOD

This prospective analysis included 241 patients with knee osteoarthritis (OA) undergoing unilateral TKA who completed questionnaires preoperatively and up to 12 months post-operatively. Questionnaires included the Western Ontario and McMaster Universities Osteoarthritis Index (WOMAC) pain scale and a body pain diagram. We derived the number of non-index painful body regions from the diagram. We used Poisson regression to determine the association between painful body regions identified preoperatively and both WOMAC pain at follow-up and improvement in pain as defined by the minimal clinically important difference (MCID).

RESULTS

Mean subject age was 66 years (SD 9), and 61% were females. Adjusting for age, sex, co-morbid conditions, baseline pain, pain catastrophizing, and mental health, we found that more widespread body pain was associated with a higher likelihood of reporting 12-month WOMAC pain score >15 (relative risk [RR] per painful body region 1.39, 95% CI 1.18-1.63) and a greater likelihood of failing to achieve the MCID (RR 1.47, 95% CI 1.16-1.86).). Pain catastrophizing was an independent predictor of persistent pain and failure to improve by the MCID (RR 3.57, 95% CI 1.73-7.31).

CONCLUSIONS

Pre-operative widespread pain was associated with greater pain at 12-months and failure to reach the MCID. Widespread pain as captured by the pain diagram, along with the pain catastrophizing score, may help identify persons with suboptimal TKA outcome.

Association between pain sensitivity in the hand and outcomes after surgery in patients with lumbar disc herniation or spinal stenosis

PURPOSE

To investigate the association between pain sensitivity in the hand pre-surgery, and patient-reported outcomes (PROs) in function, pain and health pre- and post-surgery in patients with disc herniation or spinal stenosis.

METHODS

This is a prospective cohort study with 82 patients. Associations between pressure-, cold- and heat pain threshold (PPT, CPT, HPT) in the hand pre-surgery and Oswestry, VAS pain, EQ-5D, HADS, and Self-Efficacy Scale, pre- and three months post-surgery; were investigated with linear regression.

RESULTS

Patients with disc herniation more sensitive to pressure pain pre-surgery showed lower function and self-efficacy, and higher anxiety and depression pre-surgery, and lower function, and self-efficacy, and higher pain post-surgery. Results for cold pain were similar. In patients with spinal stenosis few associations with PROs were found and none for HPT and PROs.

CONCLUSIONS

Altered pain response in pressure- and cold pain in the hand, as a sign of widespread pain pre-surgery had associations with higher pain, lower function and self-efficacy post-surgery in patients with disc herniation.

The concurrence of musculoskeletal pain and associated work-related factors: a cross sectional study

Background

Several recent studies have described the presence of musculoskeletal complaints, presenting evidence that multisite musculoskeletal pain (MP) is more often present than single-site musculoskeletal pain. However, less is known about determinants of this multimorbidity, particularly, concerning the role of occupational factors and, mainly, what determines single or multisite pain. This study described the associations between pain in different body sites and investigated related factors to MP in workers from Brazil.

Methods

A total of 1070 workers (228 women and 842 men), from urban cleaning services and from shoe manufacturers, participated in this cross sectional study (response 97 %). Interviewer-administered questionnaire included sociodemographic factors, physical and psychosocial work demands, leisure-time activities and musculoskeletal pain which was presence of pain in previous seven days, considering eight body sites and MP, the sum score of all painful sites, varying 0–8. A factor analysis was performed that captured the nine variables of physical exposure into two latent factors. Associations of pain between different body sites were assessed. Cox regression analyses, presenting the prevalence ratio (PR), showed the related factors to MP.

Results

In the previous seven days, 30 % of workers had MP. For all body sites, comorbidity ranged from 72 % to 91 %. Having pain in one body site is associated with pain in other site and the associations between proximal sites were stronger than between more distal sites. High exposure to manual material handling and awkward postures (PR = 1.5, 95 % CI 1.1–2.0), job strain (PR = 1.2, 95 % CI 1.0–1.6), and low social support (PR = 1.3, 95 % CI 1.0–1.7) and being woman (PR = 1.7, 95 % CI 1.3–2.3) were associated with MP. Risk factors for single–site pain and for subsequent musculoskeletal comorbidity were very similar, suggesting an additive effect of risk factors.

Conclusions

Most workers reported MP that was associated with several work-related factors. The findings support the idea that multisite pain is a continuum of single-site pain, maintained by exposure to several risk factors, rather than the result of a specific risk factor that initiates the multisite pain but not single-site pain. Workplace interventions are needed to decrease the number of pain sites, in order to improve the worker’s health.

Associations of multisite pain with healthcare utilization, sickness absence and restrictions at work

Purpose

Despite the apparent importance of multisite musculoskeletal pain (MMP) for functioning, there is still a lack of studies that have investigated the influence of MMP on healthcare utilization (HU), sickness absence (SA) and restrictions of work (RW). This study described the HU, SA and RW due to musculoskeletal pain (MP) in different body sites and according to number of pain sites and investigated associations between number of pain sites with these three outcomes in workers from Bahia, Brazil.

Methods

This study was based on two cross-sectional surveys carried out in 2010 and 2012. The response in the pooled data was 97 % (n = 1070, 228 women and 842 men). Interviewer-administered questionnaire was used with questions on HU, SA and RW due to MP. The number of pain sites is the sum score of eight body sites with pain in previous 12 months. Covariates were age, gender, physical and psychosocial work demands, leisure-time physical activities and body mass index. Cox regression models, properly applied to a cross-sectional study, determined the associations between number of pain sites with the three outcomes.

Results

Prevalence of MP in the previous 12 months is 81.2 %, and MMP accounted for two-thirds of pain. We found consistently increasing occurrence of HU, SA and RW with increasing number of pain sites. For individuals with pain in four or more body sites, the utilization of health care was 1.7-fold the utilization by workers with single-site pain. Having pain in four or more sites increased the prevalence of SA 3.6-fold and of RW 4.0-fold compared with having single-site pain, after adjustment by covariates.

Conclusions

The functional consequences of pain depend on how much body regions are affected, i.e., the more widespread pain, the higher the likelihood of medical consumption, sickness absence and restricted work. Given the high comorbidity, the number of pain sites, instead of specific body site of pain, seems to be a useful measure to anticipate interventions at workplaces for musculoskeletal disease prevention.

Widespread pain - do pain intensity and care-seeking influence sickness absence? - A population-based cohort study

Background

Both musculoskeletal pain-intensity in relation to a specific location (e.g. lower back or shoulder) and pain in multiple body regions have been shown to be associated with impaired function and sickness absence, but the impact of pain intensity on the association between widespread pain and sickness absence has not been studied. Additionally it is unknown whether care-seeking in general practice due to musculoskeletal disorders has a positive or negative impact on future absenteeism.

The purpose of this study was to examine the influence of pain intensity on the association between number of musculoskeletal pain sites and sickness absence, and to analyze the impact on absenteeism from care-seeking in general practice due to musculoskeletal disorders.

Methods

3745 Danish adults registered with eight General Practitioners (GPs) in one primary medical center reported location and intensity of experienced musculoskeletal pain in seven different body regions in February 2008. Outcome was duration of sickness absence based on register data divided into long-term (>52 weeks during follow-up) and sickness absence of shorter duration (12–52 weeks during follow-up) over a period of 4 years. Data on pain-intensity were analyzed at three different cut-off levels for each body region: i) > 1 (any pain), ii) > 2 (bothersome pain), iii) > 3 (very bothersome pain). Analyses were stratified and compared between participants without GP contact and participants with GP contact due to musculoskeletal disorders.

Results

Musculoskeletal pain in more than two body regions was strongly associated with long-term sickness absence in an exposure-response pattern. Different cut-off levels of pain intensity and adjustment for age, sex, educational level and work environmental factors did not alter the results. Similar findings were observed for sickness absence of shorter duration, although the association was weaker. Care-seeking in general practice due to musculoskeletal disorders did not overall alter the odds of later sickness absence.

Conclusion

Pain intensity and care-seeking due to musculoskeletal disorders did not seem to influence the association between the number of pain sites and later sickness absence. The number of musculoskeletal pain sites seems to be a strong risk factor for later sickness absence.

Association Between Widespread Pain Scores and Functional Impairment and Health-Related Quality of Life in Clinical Samples of Children

Pain involving several body regions generally represents nervous system pathophysiology shifting from predominantly peripheral to more central. In adults, higher widespread pain scores are clinically meaningful and confer risk for poor response to treatment. It is unknown whether widespread pain is similarly important in children. To address this gap, we conducted an observational study examining 1) associations between widespread pain and functional impairment and health-related quality of life (HRQOL) in clinical pediatric samples, and 2) associations among sociodemographic factors and pain catastrophizing with widespread pain scores. Participants were 166 children aged 10 to 18 years from 3 samples (acute pain, presurgery, chronic pain). Children self-reported pain intensity, pain catastrophizing, functional impairment, and HRQOL. Children indicated pain locations on a body diagram, which was coded using the American College of Rheumatology definition of widespread pain. Results revealed higher widespread pain scores were associated with greater functional impairment with routine activities (F = 3.15, P = .02) and poorer HRQOL (F = 3.29, P = .02), adjusting for pain intensity, study group, and demographic characteristics. Older age (B = .11, P = .02), and Hispanic ethnicity (B = .67, P = .04) were associated with higher widespread pain scores. Findings support incorporating evaluation of widespread pain into pediatric pain assessment. Future research is needed to examine the longitudinal effect of widespread pain on children's treatment outcomes.

PERSPECTIVE

This article examines the association between widespread pain scores and functional impairment and HRQOL in community and clinical samples of children. Assessment of the spatial distribution of the pain experience provides unique information that may identify children at risk for poorer health.

Effect of Milnacipran Treatment on Ventricular Lactate in Fibromyalgia: A Randomized, Double-Blind, Placebo-Controlled Trial

Milnacipran, a serotonin/norepinephrine reuptake inhibitor, has been approved by the US Food and Drug Administration for the treatment of fibromyalgia (FM). This report presents the results of a randomized, double-blind, placebo-controlled trial of milnacipran conducted to test the hypotheses that a) similar to patients with chronic fatigue syndrome, patients with FM have increased ventricular lactate levels at baseline; b) 8 weeks of treatment with milnacipran will lower ventricular lactate levels compared with baseline levels and with ventricular lactate levels after placebo; and c) treatment with milnacipran will improve attention and executive function in the Attention Network Test compared with placebo. In addition, we examined the results for potential associations between ventricular lactate and pain. Baseline ventricular lactate measured by proton magnetic resonance spectroscopic imaging was found to be higher in patients with FM than in healthy controls (F1,37 = 22.11, P < .0001, partial η(2) = .37). Milnacipran reduced pain in patients with FM relative to placebo but had no effect on cognitive processing. At the end of the study, ventricular lactate levels in the milnacipran-treated group had decreased significantly compared with baseline and after placebo (F1,18 = 8.18, P = .01, partial η(2) = .31). A significantly larger proportion of patients treated with milnacipran showed decreases in both ventricular lactate and pain than those treated with placebo (P = .03). These results suggest that proton magnetic resonance spectroscopic imaging measurements of lactate may serve as a potential biomarker for a therapeutic response in FM and that milnacipran may act, at least in part, by targeting the brain response to glial activation and neuroinflammation.

PERSPECTIVE

Patients treated with milnacipran showed decreases in both pain and ventricular lactate levels compared with those treated with placebo, but, even after treatment, levels of ventricular lactate remained higher than in controls. The hypothesized mechanism for these decreases is via drug-induced reductions of a central inflammatory state.

Pain in primary Sjögren's syndrome

Joint and muscle pain are commonly observed in patients with primary Sjögren's syndrome (pSS). Different types of pain can be distinguished, that is, articular pain, neuropathic pain and widespread pain. Articular pain is due to more or less evident synovitis, usually involving peripheral joints such as hand joints, wrists, knees and ankles. Drugs used to treat rheumatoid arthritis, or lupus synovitis, are also employed for articular involvement in pSS. Pure sensory neuropathies and, more often, small fibre neuropathies are responsible for neuropathic pain in pSS. This is usually localised in the legs and arms with a characteristic glove or sock distribution. Widespread pain, often assuming the features of fibromyalgia, has also been reported in patients with pSS. The pathological mechanisms underlying both neuropathic pain and widespread (fibromyalgia) pain in pSS have not been so far completely clarified.

Palmitoylethanolamide and stearoylethanolamide levels in the interstitium of the trapezius muscle of women with chronic widespread pain and chronic neck-shoulder pain correlate with pain intensity and sensitivity

Chronic widespread pain (CWP) is a complex condition characterized by central hyperexcitability and altered descending control of nociception. However, nociceptive input from deep tissues is suggested to be an important drive. N-Acylethanolamines (NAEs) are endogenous lipid mediators involved in regulation of inflammation and pain. Previously we have reported elevated levels of the 2 NAEs, the peroxisome proliferator-activated receptor type-α ligand N-palmitoylethanolamine (PEA) and N-stearoylethanolamine (SEA) in chronic neck/shoulder pain (CNSP). In the present study, the levels of PEA and SEA in women with CWP (n=18), CNSP (n=34) and healthy controls (CON, n=24) were investigated. All subjects went through clinical examination, pressure pain threshold measurements and induction of experimental pain in the tibialis anterior muscle. Microdialysis dialysate of the trapezius was collected before and after subjects performed a repetitive low-force exercise and analyzed by mass spectrometry. The levels of PEA and SEA in CNSP were significantly higher post exercise compared with CWP, and both pre and post exercise compared with CON. Levels of both NAEs decreased significantly pre to post exercise in CWP. Intercorrelations existed between aspects of pain intensity and sensitivity and the level of the 2 NAEs in CWP and CNSP. This is the first study demonstrating that CNSP and CWP differ in levels of NAEs in response to a low-force exercise which induces pain. Increases in pain intensity as a consequence of low-force exercise were associated with low levels of PEA and SEA in CNSP and CWP. These results indicate that PEA and SEA have antinociceptive roles in humans.