Exercise Strengthens Central Nervous System Modulation of Pain in Fibromyalgia

Conservative Management of Occipital Neuralgia Supported by Physical Therapy: A Review of Available Research and Mechanistic Rationale to Guide Treatment

PURPOSE OF REVIEW

Conservative management is consistently recommended as a first line intervention for occipital neuralgia (ON); however, there is limited clinical research regarding conservative intervention for ON. This lack of research may lead to underutilization or unwarranted variability in conservative treatment. This article provides mechanism-based guidance for conservative management of ON as a component of a multimodal treatment approach, and discusses the role of the physical therapist in the care team. It also highlights opportunities for further research to refine conservative management of this condition.

RECENT FINDINGS

Published research on conservative interventions specific to ON is limited to very low-quality evidence for the use of TENS. The contemporary shift toward precision pain management emphasizing treatment based on a patient's constellation of clinical features-a phenotype-rather than solely a diagnosis provides more personalized and specifically targeted pain treatment. This paradigm can guide treatment in cases where diagnosis-specific research is lacking and can be used to inform conservative treatment in this case. Various conservative interventions have demonstrated efficacy in treating many of the symptoms and accepted etiologies of ON. Conservative interventions provided by a physical therapist including exercise, manual therapy, posture and biomechanical training, TENS, patient education, and desensitization have mechanistic justification to treat symptoms and causes of ON. Physical therapists have adequate time and skill to provide such progressive and iterative interventions and should be included in a multimodal treatment plan for ON. Further research is required to determine appropriate dosing, sequencing, and progression of conservative treatments.

Pathology of pain and its implications for therapeutic interventions

Pain is estimated to affect more than 20% of the global population, imposing incalculable health and economic burdens. Effective pain management is crucial for individuals suffering from pain. However, the current methods for pain assessment and treatment fall short of clinical needs. Benefiting from advances in neuroscience and biotechnology, the neuronal circuits and molecular mechanisms critically involved in pain modulation have been elucidated. These research achievements have incited progress in identifying new diagnostic and therapeutic targets. In this review, we first introduce fundamental knowledge about pain, setting the stage for the subsequent contents. The review next delves into the molecular mechanisms underlying pain disorders, including gene mutation, epigenetic modification, posttranslational modification, inflammasome, signaling pathways and microbiota. To better present a comprehensive view of pain research, two prominent issues, sexual dimorphism and pain comorbidities, are discussed in detail based on current findings. The status quo of pain evaluation and manipulation is summarized. A series of improved and innovative pain management strategies, such as gene therapy, monoclonal antibody, brain-computer interface and microbial intervention, are making strides towards clinical application. We highlight existing limitations and future directions for enhancing the quality of preclinical and clinical research. Efforts to decipher the complexities of pain pathology will be instrumental in translating scientific discoveries into clinical practice, thereby improving pain management from bench to bedside.

Age- and Sex-Dependent Effects of Moderate Exercise on Endogenous Pain Inhibition in Rats

Diffuse noxious inhibitory controls (DNICs), or the pain inhibits pain phenomenon, refer to reduced pain-like behaviors that are displayed following a noxious conditioning stimulus located far from the test stimulus and have also been referred to as "descending control of nociception" when measured in awake-behaving animals. In this study, we sought to determine the impact of moderate long-term exercise on the DCN response and determine if this effect differed across age and sex. After a six-week exercise program consisting of 30 min of moderate treadmill running 5 days a week, the animals' forepaws were injected with capsaicin, and DCN responses were assessed using thermal withdrawal latencies of the hind paw. Young, exercised male and female rats displayed prolonged DCN responses relative to their sedentary counterparts, with the young exercised male group displaying longer-lasting DCN facilitation than the young exercised females. Exercise did not impact DCN responses in either male or female aged rats. Additionally, the serum testosterone levels did not change following exercise in any group. Importantly, the levels of corticosterone did not change following the exercise program, indicating that changes in the DCN response are not due to stress-induced analgesia. Our findings suggest that moderate exercise can facilitate the DCN response in young animals, even when this exercise does not change the levels of serum testosterone.

Physical activity should be the primary intervention for individuals living with chronic pain A position paper from the European Pain Federation (EFIC) 'On the Move' Task Force

BACKGROUND

There is clear evidence demonstrating the benefits of physical activity (PA) on pain and overall health, however, PA is challenging for many individuals living with chronic pain. Even non-exercise specialists can (cost) effectively promote PA, but many health professionals report a number of barriers in providing guidance on PA, suggesting that it is not consistently promoted. This expert position paper summarizes the evidence and provides five recommendations for health professionals to assess, advise and support individuals living with any chronic pain condition with a long life expectancy in adopting and sustaining physically active lifestyles.

METHODS

This position paper was prepared by the 'On The Move' Task Force of the European Pain Federation EFIC. Final recommendations were endorsed by the European Pain Forum, Pain Alliance Europe and the Executive Board of EFIC.

RESULTS

We recommend that all health professionals (1) Take a history of the persons' PA levels, and put PA on the agenda, (2) Advise that PA is important and safe for individuals living with chronic pain, (3) Deliver a brief PA intervention and support individuals living with chronic pain in becoming physically active, (4) Discuss acceptable levels of PA-related soreness and pain and (5) Provide ongoing support in staying physically active.

SIGNIFICANCE

Physical activity is safe and offers several advantages, including general health benefits, low risk of side effects, low cost and not requiring access to healthcare. Adoption of these recommendations can improve the quality of care and life of individuals living with chronic pain and reduce their overall health risks.

Cerebral Mechanism of Tuina on the Descending Pain Inhibitory System in Knee Osteoarthritis: Protocol for a Randomized Controlled Trial

BACKGROUND

Knee osteoarthritis (KOA) is reputedly the most common musculoskeletal disease of the lower limbs and the main cause of pain and disability among older individuals. Pain is the most significant and widespread symptom of KOA. The descending pain inhibitory system has a cardinal role in normal pain consciousness, and its malfunction may be one of the pathophysiological mechanisms in KOA. Crucially, the rostral ventromedial medulla (RVM) and periaqueductal gray (PAG), as important components of the descending pain inhibitory system, directly modulate the activity of the spinal neurons involved in pain transmission. Tuina, a manual therapy, is effective and safe for reducing clinical symptoms of KOA; however, the mechanism that influences pain through the descending pain inhibitory system in KOA is unclear.

OBJECTIVE

This study aims to investigate the modulatory implications of Tuina on the RVM and PAG, which have critical roles in the descending pain inhibitory system in patients with KOA.

METHODS

This randomized controlled parallel trial will be conducted at the Tuina Clinic of the Third Affiliated Hospital of Henan University of Chinese Medicine (Zhengzhou, China). Patients with KOA will be randomly assigned (1:1) to 6 weeks of health education or Tuina. All patients in both groups will accept a resting-state functional magnetic resonance scan at the beginning and end of the experiment, and the resting-state functional connectivity and the voxel-based morphometry analysis will be performed to detect the RVM and PAG function and structure changes. The clinical outcome assessments will be (1) the pressure pain thresholds, (2) the Numerical Rating Scale, (3) the Hamilton Depression Scale (HAMD), and (4) the Western Ontario and McMaster Universities Osteoarthritis Index (WOMAC). Considering that this trial is a study of resting-state functional magnetic resonance imaging technology, resting-state functional connectivity and voxel-based morphometry are the primary outcomes, and clinical outcome assessments are secondary outcomes. Adverse events will be documented and assessed throughout. All main analyses will be carried out on the basis of the intention-to-treat principle. The outcome evaluators and data statisticians will be masked to the treatment group assignment to reduce the risk of bias.

RESULTS

This trial was approved by the ethics committee of the Third Affiliated Hospital of Henan University of Chinese Medicine. Enrollment began in December 2023, and the results of this trial are expected to be submitted for publication in May 2025.

CONCLUSIONS

This trial will identify a possible relationship between function and structure changes of RVM and PAG and the improvement of clinical variables, elucidating the effect of Tuina on the descending pain inhibitory system of patients with KOA. This trial will provide much-needed knowledge for Tuina for patients with KOA.

TRIAL REGISTRATION

Chinese Clinical Trial Registry ChiCTR2300070289; https://www.chictr.org.cn/showproj.html?proj=182570.

INTERNATIONAL REGISTERED REPORT IDENTIFIER (IRRID)

PRR1-10.2196/52820.

Response to experimental cold-induced pain discloses a resistant category among endurance athletes, with a distinct profile of pain-related behavior and GABAergic EEG markers: a case-control preliminary study

Pain is a major public health problem worldwide, with a high rate of treatment failure. Among promising non-pharmacological therapies, physical exercise is an attractive, cheap, accessible and innocuous method; beyond other health benefits. However, its highly variable therapeutic effect and incompletely understood underlying mechanisms (plausibly involving the GABAergic neurotransmission) require further research. This case-control study aimed to investigate the impact of long-lasting intensive endurance sport practice (≥7 h/week for the last 6 months at the time of the experiment) on the response to experimental cold-induced pain (as a suitable chronic pain model), assuming that highly trained individual would better resist to pain, develop advantageous pain-copying strategies and enhance their GABAergic signaling. For this purpose, clinical pain-related data, response to a cold-pressor test and high-density EEG high (Hβ) and low beta (Lβ) oscillations were documented. Among 27 athletes and 27 age-adjusted non-trained controls (right-handed males), a category of highly pain-resistant participants (mostly athletes, 48.1%) was identified, displaying lower fear of pain, compared to non-resistant non-athletes. Furthermore, they tolerated longer cold-water immersion and perceived lower maximal sensory pain. However, while having similar Hβ and Lβ powers at baseline, they exhibited a reduction between cold and pain perceptions and between pain threshold and tolerance (respectively -60% and - 6.6%; -179.5% and - 5.9%; normalized differences), in contrast to the increase noticed in non-resistant non-athletes (+21% and + 14%; +23.3% and + 13.6% respectively). Our results suggest a beneficial effect of long-lasting physical exercise on resistance to pain and pain-related behaviors, and a modification in brain GABAergic signaling. In light of the current knowledge, we propose that the GABAergic neurotransmission could display multifaceted changes to be differently interpreted, depending on the training profile and on the homeostatic setting (e.g., in pain-free versus chronic pain conditions). Despite limitations related to the sample size and to absence of direct observations under acute physical exercise, this precursory study brings into light the unique profile of resistant individuals (probably favored by training) allowing highly informative observation on physical exercise-induced analgesia and paving the way for future clinical translation. Further characterizing pain-resistant individuals would open avenues for a targeted and physiologically informed pain management.

Behavioral physical activity intervention coupled with standard post-cancer directed treatment care to mitigate chronic pain in childhood cancer survivors: A protocol for a single-center, pilot randomized controlled trial

Background

Long term survivors of childhood cancer have a high prevalence of chronic pain. Novel, multidisciplinary approaches to manage pain, are needed to allow for a reduction in the use of opioids for pain management. Physical activity is highly effective in managing chronic pain in children and adolescents, however, evidence about the combination of physical activity intervention and pain medications in chronic pain management in childhood cancer survivors is lacking. The aim of this study is to investigate the feasibility, acceptability and preliminary effects of a behavioral physical activity intervention integrated into standard post cancer directed treatment care to mitigate chronic pain in this unique population.

Methods

This is a single site pilot randomized controlled trial of a 16-week physical activity intervention coupled with standard care. The primary aim is to assess the feasibility and acceptability of the physical activity intervention in childhood cancer survivors with chronic pain. Secondary aims include evaluating the differences in functional and psychosocial outcomes along with self-reported pain scores and cumulative dose of pain medications between the exercise group and standard cancer care group. The physical activity intervention is a home-based program structured to increase patients' physical activity behavior and to favor low intensity bodily movement using aerobic exercise and resistance training.

Conclusions

This study will demonstrate that behavioral supportive measures like physical activity may be a novel means to improve cancer related chronic pain in young survivors of childhood cancer and decrease medication usage for pain along with improvement in functional and psychosocial outcomes.

Physical Activity and Exercise Experience in Spanish and US Men with Fibromyalgia: A Qualitative Cross-Cultural Study

Physical exercise is an indispensable element in the multidisciplinary treatment of fibromyalgia syndrome (FMS). The present study examined if men diagnosed with FMS engaged in any type of physical activity or exercise, the perceived effects from exercise, and who specifically recommended exercise. A qualitative cross-cultural study was performed in fibromyalgia clinical units in Spain and the United States. A total of 17 participants, 10 men from Spain and 7 men from the US, were included. In Spain, a focus group was completed in two parts, one month apart in 2018. In the US, five individual interviews and one joint interview with two men were completed in 2018. Three central themes appeared in the qualitative data: (1) Understanding what constitutes physical activity or exercise, (2) Facilitating or discouraging the performance of physical exercise, and (3) Effects of physical activity or exercise on psychological and social symptoms. The actual practice of exercise by patients with FMS is often perceived as leading to pain and fatigue, rather than a treatment facilitator. Physical activity and exercise can provide benefits, including relaxation, socialization, and increased muscle tone. However, minor opioids limit physical activity as they cause addiction, drowsiness, and decrease physical activity in Spanish men. Recommendations in a clinical setting should incorporate exercise as well as physical activity via daily life activities.

The effects of physical exercise on structural, functional, and biochemical brain characteristics in individuals with chronic whiplash-associated disorder: A pilot randomized clinical trial

BACKGROUND

Exercise for people with whiplash associated disorder (WAD) induces hypoalgesic effects in some, but hyperalgesic effects in others. We investigated the exercise-induced neurobiological effects of aerobic and strengthening exercise in individuals with chronic WAD.

METHODS

Sixteen participants (8 WAD, 8 pain-free [CON]) were randomised to either aerobic or strengthening exercise. MRI for brain morphometry, functional MRI for brain connectivity, and magnetic resonance spectroscopy for brain biochemistry, were used at baseline and after the 8-week intervention.

RESULTS

There were no differences in brain changes between exercise groups in either the WAD or CON group, therefore aerobic and strengthening data were combined to optimise sample size. After the exercise intervention, the CON group demonstrated increased cortical thickness (left parahippocampus: mean difference = 0.04, 95% CI = 0.07-0.00, p = 0.032; and left lateral orbital frontal cortex: mean difference = 0.03, 95% CI = 0.00-0.06, p = 0.048). The WAD group demonstrated an increase in prefrontal cortex (right medial orbital frontal) volume (mean difference = 95.57, 95% CI = 2.30-192.84, p = 0.046). Functional changes from baseline to follow-up between the default mode network and the insula, cingulate cortex, temporal lobe, and somatosensory and motor cortices, were found in the CON group, but not in the WAD group. There were no changes post-exercise in brain biochemistry.

CONCLUSION

Aerobic and strengthening exercises did not exert differential effects on brain characteristics, however differences in structural and functional changes were found between WAD and CON groups. This suggests that an altered central pain modulatory response may be responsible for differential effects of exercise in individuals with chronic WAD.

Differential Structural Brain Changes Between Responders and Nonresponders After Physical Exercise Therapy for Chronic Nonspecific Neck Pain

OBJECTIVES

Physical exercise therapy is effective for some people with chronic nonspecific neck pain but not for others. Differences in exercise-induced pain-modulatory responses are likely driven by brain changes. We investigated structural brain differences at baseline and changes after an exercise intervention. The primary aim was to investigate changes in structural brain characteristics after physical exercise therapy for people with chronic nonspecific neck pain. The secondary aims were to investigate (1) baseline differences in structural brain characteristics between responders and nonresponders to exercise therapy, and (2) differential brain changes after exercise therapy between responders and nonresponders.

MATERIALS AND METHODS

This was a prospective longitudinal cohort study. Twenty-four participants (18 females, mean age 39.7 y) with chronic nonspecific neck pain were included. Responders were selected as those with ≥20% improvement in Neck Disability Index. Structural magnetic resonance imaging was obtained before and after an 8-week physical exercise intervention delivered by a physiotherapist. Freesurfer cluster-wise analyses were performed and supplemented with an analysis of pain-specific brain regions of interest.

RESULTS

Various changes in grey matter volume and thickness were found after the intervention, for example, frontal cortex volume decreased (cluster-weighted P value = 0.0002, 95% CI: 0.0000-0.0004). We found numerous differences between responders and nonresponders, most notably, after the exercise intervention bilateral insular volume decreased in responders, but increased in nonresponders (cluster-weighted P value ≤ 0.0002).

DISCUSSION

The brain changes found in this study may underpin clinically observed differential effects between responders and nonresponders to exercise therapy for people with chronic neck pain. Identification of these changes is an important step toward personalized treatment approaches.

Effect of exercise on chronic neck pain and central sensitization: A protocol for a randomized crossover trial

Exercise-induced hypoalgesia (EIH) has been found to vary widely within individuals with chronic neck pain (NP). Research has suggested that the presence of central sensitization within a subgroup of individuals with chronic NP might be a mediating factor to explain the relationship between exercise and improvements in patient-reported outcomes. Furthermore, recent work has found that lactate might play a role in the development and maintenance of chronic pain. The immediate effect of a single bout of physical exercise on central sensitization in individuals with chronic NP and the relationship between lactate concentration, central sensitization and pain sensitivity are to be investigated. Eighty adult participants with chronic NP will be recruited for this randomized crossover trial. Outcome measures, including temporal summation, conditioned pain modulation, EIH and lactate concentration, will be assessed before and after low- and high-intensity bicycling exercise. The outcomes of this study will provide new insights into the mechanistic effect of exercise on central sensitization in individuals with chronic NP and have the potential to add important information to the current exercise prescription guidelines for individuals with chronic NP. This study has been approved by the Human Research Ethics Committee, The University of Adelaide (H-2022-082) and registered in the Australian New Zealand Clinical Trials Registry (ACTRN12622000642785p).

Identifying body awareness-related brain network changes after Spring Forest Qigong™ practice or P.Volve low-intensity exercise in adults with chronic low back pain: a feasibility Phase I Randomized Clinical Trial

Background

Chronic low back pain (cLBP) affects the quality of life of 52 million Americans and leads to an enormous personal and economic burden. A multidisciplinary approach to cLBP management is recommended. Since medication has limited efficacy and there are mounting concerns about opioid addiction, the American College of Physicians and American Pain Society recommend non-pharmacological interventions, such as mind and body approaches (e.g., Qigong, yoga, Tai Chi) before prescribing medications. Of those, Qigong practice might be most accessible given its gentle movements and because it can be performed standing, sitting, or lying down. The three available Qigong studies in adults with cLBP showed that Qigong reduced pain more than waitlist and equally well than exercise. Yet, the duration and/or frequency of Qigong practice were low (<12 weeks or less than 3x/week). The objectives of this study were to investigate the feasibility of practicing Spring Forest Qigong™ or performing P.Volve low intensity exercises 3x/week for 12 weeks, feasibility of recruitment, data collection, delivery of the intervention as intended, as well as identify estimates of efficacy on brain function and behavioral outcomes after Qigong practice or exercise. To our knowledge, this is the first study investigating the feasibility of the potential effect of Qigong on brain function in adults with cLBP.

Methods

We conducted a feasibility Phase I Randomized Clinical Trial. Of the 36 adults with cLBP recruited between January 2020 and June 2021, 32 were enrolled and randomized to either 12 weeks of remote Spring Forest Qigong™ practice or remote P.Volve low-intensity exercises. Participants practiced at least 3x/week for 41min/session with online videos. Our main outcome measures were the Numeric Pain Rating Scale (highest, average, and lowest cLBP pain intensity levels in the prior week), assessed weekly and fMRI data (resting-state and task-based fMRI tasks: pain imagery, kinesthetic imagery of a Qigong movement, and robot-guided shape discrimination). We compared baseline resting-state connectivity and brain activation during fMRI tasks in adults with cLBP with data from a healthy control group (n=28) acquired in a prior study. Secondary outcomes included measures of function, disability, body awareness, kinesiophobia, balance, self-efficacy, core muscle strength, and ankle proprioceptive acuity with a custom-build device.

Results

Feasibility of the study design and methods was demonstrated with 30 participants completing the study (94% retention) and reporting high satisfaction with the programs; 96% adherence to P.Volve low-intensity exercises, and 128% of the required practice intensity for Spring Forest Qigong™ practice. Both groups saw promising reductions in low back pain (effect sizes Cohen's d =1.01-2.22) and in most other outcomes ( d =0.90-2.33). Markers of ankle proprioception were not significantly elevated in the cLBP group after the interventions. Brain imaging analysis showed weaker parietal operculum and insula network connectivity in adults with cLBP (n=26), compared to data from a healthy control group (n=28). The pain imagery task elicited lower brain activation of insula, parietal operculum, angular gyrus and supramarginal gyrus at baseline in adults with cLBP than in healthy adults. Adults with cLBP had lower precentral gyrus activation than healthy adults for the Qigong movement and robot task at baseline. Pre-post brain function changes showed individual variability: Six (out of 13) participants in the Qigong group showed increased activation in the parietal operculum, angular gyrus, supramarginal gyrus, and precentral gyrus during the Qigong fMRI task.

Interpretation

Our data indicate the feasibility and acceptability of using Spring Forest Qigong™ practice or P.Volve low-intensity exercises for cLBP relief showing promising results in terms of pain relief and associated symptoms. Our brain imaging results indicated brain function improvements after 12 weeks of Qigong practice in some participants, pointing to the need for further investigation in larger studies.

Trial registration number

ClinicalTrials.gov: NCT04164225 .

Effect and mechanisms of exercise for complex regional pain syndrome

Complex regional pain syndrome characterized by severe pain and dysfunction seriously affects patients' quality of life. Exercise therapy is gaining attention because it can effectively relieve pain and improve physical function. Based on the previous studies, this article summarized the effectiveness and underlying mechanisms of exercise interventions for complex regional pain syndrome, and described the gradual multistage exercise program. Exercises suitable for patients with complex regional pain syndrome mainly include graded motor imagery, mirror therapy, progressive stress loading training, and progressive aerobic training. In general, exercise training for patients with complex regional pain syndrome not only alleviates pain but also improves physical function and positive mental status. The underlying mechanisms of exercise interventions for complex regional pain syndrome include the remodeling of abnormal central and peripheral nervous system, the regulation of vasodilation and adrenaline levels, the release of endogenous opioids, and the increased anti-inflammatory cytokines. This article provided a clear explanation and summary of the research on exercise for complex regional pain syndrome. In the future, more high-quality studies with sufficient sample sizes may provide more exercise regimens and better evidence of efficacy.

Exercise-Induced Hypoalgesia Following Proprioceptive Neuromuscular Facilitation and Resistance Training Among Individuals With Shoulder Myofascial Pain: Randomized Controlled Trial

BACKGROUND

Various exercises can attenuate pain perception in healthy individuals and may interact with the descending pain modulation in the central nervous system. However, the analgesic effects of exercise in patients with myofascial pain can be disrupted by the pathological changes during chronic pain conditions. Thus, the exercises targeted on the facilitation of the sensory-motor interaction may have a positive impact on the restoration of the descending pain modulation and the analgesia effects.

OBJECTIVE

This paper estimates the effect of proprioceptive neuromuscular facilitation (PNF) and resistance training on exercise-induced hypoalgesia (EIH) and conditioned pain modulation (CPM) among patients with myofascial pain syndrome.

METHODS

A total of 76 female patients with myofascial pain syndrome (aged 18-30 years), with the pain in the upper trapezius and a visual analog scale score of greater than 30/100 mm, were enrolled in the study. Participants were randomly assigned into 3 intervention groups, including isometric (n=18, 24%), isotonic (n=19, 25%), and PNF (n=20, 26%) exercises, as well as 1 control group (n=19, 25%) with no intervention. Pressure pain threshold and the CPM responses at the myofascial trigger point, arm, and leg sites were assessed before and after the exercise session. The effective EIH response was reflected in the improvement of pressure pain thresholds.

RESULTS

There was an increase in pressure pain thresholds and CPM responses at trigger point (P<.001 and P<.001), arm (P<.001 and P<.001), and leg sites (P<.001 and P=.03) in participants who performed PNF and isotonic exercise, while the isometric exercise only increased pressure pain thresholds at leg sites (P=.03). Compared with the control group, both the isotonic (P=.02) and PNF (P<.001) groups showed greater EIH responses at the trigger points. In comparison to the control group, only the PNF exercise (P=.01) significantly improved pressure pain thresholds and CPM responses at arm and leg sites compared to the control group.

CONCLUSIONS

PNF, isotonic, and isometric exercises could lead to local and global EIH effects. The improvement in CPM response following PNF and isotonic exercises suggested that the EIH mechanisms of different resistance exercises may be attributed to the enhancement of the endogenous pain modulation via the motor-sensory interaction from the additional eccentric and dynamic muscle contraction.

TRIAL REGISTRATION

Chinese Clinical Trial Registry ChiCtr202111090819166165; https://tinyurl.com/2ab93p7n.

Digital rehabilitation for hand and wrist pain: a single-arm prospective longitudinal cohort study

Supplemental Digital Content is Available in the Text.

This study supports that a fully remote digital care program is feasible and able to promote high patient engagement in the telerehabilitation of patients with wrist and hand pain.

Introduction:

Wrist and hand represent the third most common body part in work-related injuries, being associated with long-term absenteeism. Telerehabilitation can promote access to treatment, patient adherence, and engagement, while reducing health care–related costs.

Objective:

Report the results of a fully remote digital care program (DCP) for wrist and hand pain (WP).

Methods:

A single-arm interventional study was conducted on individuals with WP applying for a DCP. Primary outcome was the mean change in the Numerical Pain Rating Scale after 8 weeks (considering a minimum clinically important change of 30%). Secondary outcomes were: disability (Quick Disabilities of the Arm, Shoulder, and Hand questionnaire), analgesic intake, surgery intention, mental health (patient health questionnaire [PHQ-9] and generalized anxiety disorder [GAD-7]), fear-avoidance beliefs (FABQ-PA), work productivity and activity impairment, and engagement.

Results:

From 189 individuals starting the DCP, 149 (78.8%) completed the intervention. A significant pain improvement was observed (51.3% reduction (2.26, 95% CI 1.73; 2.78)) and 70.4% of participants surpassing minimum clinically important change. This change correlated with improvements in disability (52.1%), FABQ-PA (32.2%), and activities impairment recovery (65.4%). Improvements were also observed in other domains: surgery intent (76.1%), mental health (67.0% in anxiety and 72.7% in depression), and overall productivity losses (68.2%). Analgesic intake decreased from 22.5% to 7.1%. Mean patient satisfaction score was 8.5/10.0 (SD 1.8).

Conclusions:

These findings support the feasibility and utility of a fully remote DCP for patients with WP. Clinically significant improvements were observed in all health-related and productivity-related outcomes, alongside very high patient adherence rates and satisfaction. This study strengthens that management of WP is possible through a remote DCP, decreasing access barriers and potentially easing health care expenditure.

The Benefits of a Therapeutic Exercise and Educational Intervention Program on Central Sensitization Symptoms and Pain-Related Fear Avoidance in Breast Cancer Survivors

BACKGROUND

Central sensitization symptoms and pain-related fear avoidance are two common problems in breast cancer survivors. Non-pharmacologic interventions such as therapeutic exercise and patient education can be effective in this population.

AIMS

This study aimed to: (1) analyze the benefits of a therapeutic exercise and educational program on central sensitization symptoms and pain-related fear avoidance in breast cancer survivors, and (2) explore the association between pain-related fear avoidance and central sensitization symptoms.

DESIGN

A single group pre-post intervention study was conducted.

METHODS

Patients were recruited from the service of Medical Oncology of the University Clinical Hospital Virgen de la Victoria, in Málaga (Spain). The intervention consisted of a therapeutic exercise and educational program that lasted 12 weeks, twice a week, for 1 hour. Two instruments were used: the Spanish version of the Central Sensitization Inventory and the Spanish Fear Avoidance Components Scale.

RESULTS

A total of 82 breast cancer survivors participated in the study. Pre-post change on Central Sensitization Inventory was statistically significant (p = .007). There was a trend towards a significant difference for the Spanish Fear Avoidance Components Scale (p = .062). There was a statistically significant correlation between pain-related fear avoidance and central sensitization symptoms (r = 0.536, p < .001).

CONCLUSIONS

The current study has provided preliminary evidence on the benefits of this intervention in pain-related fear avoidance and central sensitization symptoms in breast cancer survivors. The Spanish version of the Central Sensitization Inventory and the Spanish Fear Avoidance Components Scale demonstrated responsiveness to change.

Mechanisms, Mediators, and Moderators of the Effects of Exercise on Chemotherapy-Induced Peripheral Neuropathy

Chemotherapy-induced peripheral neuropathy (CIPN) is an adverse effect of neurotoxic antineoplastic agents commonly used to treat cancer. Patients with CIPN experience debilitating signs and symptoms, such as combinations of tingling, numbness, pain, and cramping in the hands and feet that inhibit their daily function. Among the limited prevention and treatment options for CIPN, exercise has emerged as a promising new intervention that has been investigated in approximately two dozen clinical trials to date. As additional studies test and suggest the efficacy of exercise in treating CIPN, it is becoming more critical to develop mechanistic understanding of the effects of exercise in order to tailor it to best treat CIPN symptoms and identify who will benefit most. To address the current lack of clarity around the effect of exercise on CIPN, we reviewed the key potential mechanisms (e.g., neurophysiological and psychosocial factors), mediators (e.g., anti-inflammatory cytokines, self-efficacy, and social support), and moderators (e.g., age, sex, body mass index, physical fitness, exercise dose, exercise adherence, and timing of exercise) that may illuminate the relationship between exercise and CIPN improvement. Our review is based on the studies that tested the use of exercise for patients with CIPN, patients with other types of neuropathies, and healthy adults. The discussion presented herein may be used to (1) guide oncologists in predicting which symptoms are best targeted by specific exercise programs, (2) enable clinicians to tailor exercise prescriptions to patients based on specific characteristics, and (3) inform future research and biomarkers on the relationship between exercise and CIPN.

'Physio-EndEA' Study: A Randomized, Parallel-Group Controlled Trial to Evaluate the Effect of a Supervised and Adapted Therapeutic Exercise Program to Improve Quality of Life in Symptomatic Women Diagnosed with Endometriosis

Aim: The ‘Physio-EndEA’ study aims to explore the potential benefits of a therapeutic exercise program (focused on lumbopelvic stabilization and tolerance to exertion) on the health-related quality of life (HRQoL) of symptomatic endometriosis women. Design: The present study will use a parallel-group randomized controlled trial design. Methods: A total of 22 symptomatic endometriosis women will be randomized 1:1 to the Physio-EndEA or usual care groups. The ‘Physio-EndEA’ program will consist of a one-week lumbopelvic stabilization learning phase followed by an eight-week phase of stretching, aerobic and resistance exercises focused on the lumbopelvic area that will be sequentially instructed and supervised by a trained physiotherapist (with volume and intensity progression) and adapted daily to the potential of each participant. The primary outcome measure is HRQoL. The secondary outcome measures included clinician-reported outcomes (pressure pain thresholds, muscle thickness and strength, flexibility, body balance and cardiorespiratory fitness) and patient-reported outcomes (pain intensity, physical fitness, chronic fatigue, sexual function, gastrointestinal function and sleep quality). Discussion: Findings of this study will help to identify cost-effective non-pharmacological options (such as this exercise-based intervention) that may contribute to the improvement of HRQoL in symptomatic endometriosis women.

Multidisciplinary rehabilitation treatments for patients with fibromyalgia: a systematic review

INTRODUCTION

Fibromyalgia (FM) is a pathology that causes physical, psychological, and social problems. For this reason, it requires treatment that involves all of these elements. The main of study is to examine multidisciplinary rehabilitation treatment (MRT) in fibromyalgia and to identify healthcare approaches developing effective MRT tools for the treatment of FM.

EVIDENCE ACQUISITION

In this systematic review, we searched the following databases: CINAHL, PubMed, Scopus, Cuidatge, Cuiden, ENFISPO, IBEC and IME.

EVIDENCE SYNTHESIS

Of 356 articles found we selected 13 to analyze and summarize. We created 4 different categories: 1) multidisciplinary rehabilitation treatment focusing on health education and cognitive behavioral therapy (CBT); 2) multidisciplinary rehabilitation treatment that includes dietetics; 3) multidisciplinary rehabilitation treatment adapted to the patients' characteristics; 4) multidisciplinary rehabilitation treatment based on physical exercise.

CONCLUSIONS

This review identifies the most effective treatments that may be usefully applied in many different rehabilitation contexts. These include all treatments that incorporated an education (ED) program to patients and an exercise program complete with aerobic exercise (AE), stretching (SE), relaxation (RE), strengthening (TE), endurance (EN), and which includes the entire body and biofeedback. Furthermore, many approaches also include cognitive behavioral therapy (CBT) for self-management such as occupational therapy, moderation, acceptance, commitment, motivation to change and forgiveness.

Brain Structural Changes during Juvenile Fibromyalgia: Relationships with Pain, Fatigue and Functional Disability

Objective

Juvenile fibromyalgia (FM) is a prevalent chronic pain condition affecting children and adolescents worldwide during a critical period of brain development. To date, no published studies have addressed the pathophysiology of juvenile FM. This study was undertaken to characterize gray matter volume (GMV) alterations in juvenile FM patients for the first time, and to investigate their functional and clinical relevance.

Methods

Thirty‐four female adolescents with juvenile FM and 38 healthy adolescents underwent a structural magnetic resonance imaging examination and completed questionnaires assessing core juvenile FM symptoms. Using voxel‐based morphometry, we assessed between‐group GMV differences and associations between GMV and functional disability, fatigue, and pain interference in juvenile FM. We also studied whether validated brain patterns predicting pain, cognitive control, or negative emotion were amplified/attenuated in juvenile FM patients and whether structural alterations reported in adult FM were replicated in adolescents with juvenile FM.

Results

Compared to controls, juvenile FM patients showed GMV reductions in the anterior midcingulate cortex (aMCC) region (family‐wise error corrected P [P_FWE‐corr] = 0.04; estimated with threshold‐free cluster enhancement [TFCE]; n = 72) associated with pain. Within the juvenile FM group, patients reporting higher functional disability had larger GMV in inferior frontal regions (P_FWE‐corr = 0.006; TFCE estimated; n = 34) linked to affective, self‐referential, and language‐related processes. Last, GMV reductions in juvenile FM showed partial overlap with findings in adult FM, specifically for the anterior/posterior cingulate cortices (P = 0.02 and P = 0.03, respectively; n = 72).

Conclusion

Pain‐related aMCC reductions may be a structural hallmark of juvenile FM, whereas alterations in regions involved in emotional, self‐referential, and language‐related processes may predict disease impact on patients’ well‐being. The partial overlap between juvenile and adult FM findings strengthens the importance of early symptom identification and intervention to prevent the transition to adult forms of the disease.

Muscle-brain communication in pain: The key role of myokines

Pain is the most common reason for a physician visit, which accounts for a considerable proportion of the global burden of disease and greatly affects patients' quality of life. Therefore, there is an urgent need to identify new therapeutic targets involved in pain. Exercise-induced hypoalgesia (EIH) is a well known phenomenon observed worldwide. However, the available evidence demonstrates that the mechanisms of EIH remain unclear. One of the most accepted hypotheses has been the activation of several endogenous systems in the brain. Recently, the concept that the muscle acts as a secretory organ has attracted increasing attention. Proteins secreted by the muscle are called myokines, playing a critical role in communicating with other organs, such as the brain. This review will focus on several myokines and discuss their roles in EIH.

Pain-related post-exertional malaise in Myalgic Encephalomyelitis/Chronic Fatigue Syndrome (ME/CFS) and Fibromyalgia: A systematic review and three-level meta-analysis

OBJECTIVE

Myalgic Encephalomyelitis/Chronic Fatigue Syndrome (ME/CFS) and Fibromyalgia (FM) are two debilitating, moderately comorbid illnesses in which chronic musculoskeletal pain symptoms are prevalent. These individuals can experience post-exertional malaise (PEM), a phenomenon where symptom severity is worsened 24hr or longer following physical stress, but the pain-related component of PEM is not well characterized.

DESIGN

Systematic review and meta-analysis.

METHODS

Case-control studies involving adults with ME/CFS or FM and measuring pain symptoms before and after exposure to a standardized aerobic exercise test were included. Hedges' d effect sizes were aggregated using random effects models and potential moderators were explored with meta-regression analysis. Results were adjusted for nesting effects using three-level modeling.

RESULTS

Forty-five effects were extracted from 15 studies involving 306 patients and 292 healthy controls. After adjusting for nesting effects, we observed a small-to-moderate effect indicating higher post-exercise pain in patients than controls (Hedges' d=0.42; 95% CI: 0.16, 0.67). The mean effect was significantly moderated by pain measurement timepoint (b = -0.19, z = -2.57, P = 0.01) such that studies measuring pain 8-72hr post-exercise showed larger effects (d = 0.71, 95% CI = 0.28-1.14) than those measuring pain 0-2hr post-exercise (d = 0.32, 95% CI = 0.10-0.53).

CONCLUSIONS

People with ME/CFS and FM experience small-to-moderate increases in pain severity following exercise which confirms pain as a component of PEM and emphasizes its debilitating impact in ME/CFS and FM. Future directions include determining mechanisms of pain-related PEM and developing exercise prescriptions that minimize symptom exacerbation in these illnesses.

Aerobic Exercise Attenuates Pain Sensitivity: An Event-Related Potential Study

In this study, electroencephalography (EEG) was utilized to explore the neurophysiological mechanisms of aerobic exercise-induced hypoalgesia (EIH) and provide a theoretical basis for the application of aerobic exercise in pain assessment and treatment. Forty-five healthy subjects were randomly divided into moderate-intensity aerobic exercise [70% heart rate reserve (HRR)], low-intensity aerobic exercise (50% HRR), or control groups (sitting). Aerobic exercise was performed with cycling. Pressure pain threshold (PPT), heat pain threshold (HPT), event-related potential (ERP) induced by contact heat stimulus and pain scoring were measured before and after the intervention. We found that moderate-intensity aerobic exercise can increase the PPT (rectus femoris: t = -2.71, p = 0.017; tibialis anterior muscle: t = -2.36, p = 0.033) and HPT (tibialis anterior muscle: t = -2.219, p = 0.044) of proximal intervention sites rather than distal sites, and decreased pain scorings of contact heat stimulus. After moderate-intensity aerobic exercise, alpha oscillation power reflecting the central descending inhibitory function was enhanced (t = -2.31, p < 0.05). Low-intensity aerobic exercise mainly reduced the pain unpleasantness rating (Block 1: t = 2.415, p = 0.030; Block 2: t = 3.287, p = 0.005; Block 4: t = 2.646, p = 0.019; Block 5: t = 2.567, p = 0.022). Aerobic exercise had an overall EIH effect. Its hypoalgesic effect was related to exercise intensity and affected by the site and type of pain stimulus. Moderate-intensity aerobic exercise effectively reduced the sensitivity to various painful stimuli, and low-intensity aerobic exercise selectively inhibited the negative emotional pain response. The hypoalgesic mechanism of aerobic exercise involves the enhancement of the central descending inhibitory function.

The Effects of Transcranial Direct Current Stimulation Combined with Aerobic Exercise on Pain Thresholds and Electroencephalography in Healthy Adults

OBJECTIVES

We examined whether transcranial direct current stimulation (tDCS) combined with aerobic exercise (AE) modulated the pressure pain threshold (PPT) and peak alpha frequency (PAF) measured via resting electroencephalography.

DESIGN

Single-blind experimental study with a cross-over design.

SETTING

Neuro Rehabilitation Research Center, Kio University.

SUBJECTS

Ten healthy controls participated in this study.

METHODS

Three types of sessions--(i) tDCS, (ii) Sham tDCS/AE, and (iii) tDCS/AE--were tested in this investigation. Anodal stimulation (2 mA, 20 minutes) was applied over the left primary motor cortex. Each session was 20 minutes long. We used the PPT and short-form Profile of Mood States-Brief, as well as PAF measured via resting-electroencephalography, to investigate the effects of tDCS and AE. Heart rate and scores on the Borg scale were used to confirm exercise intensity. PAF was calculated in four regions of interest: frontal, central, parietal, and occipital areas.

RESULTS

The change ratio of PPT increased during each session. The maximum change ratio of PPT were tDCS: 40.7%, Sham tDCS/AE: 51.5%, and tDCS/AE: 83.4%. change ratio of PPT was earlier and higher in the tDCS/AE trials compared with the other sessions. Negative mood was improved after session completion. Significant differences in PAF were found in the occipital area in the Sham tDCS/AE and tDCS/AE sessions.

CONCLUSIONS

The combined tDCS and AE intervention induced significant changes in PPT in a single session, with a PAF that was earlier and higher than those produced during the Sham tDCS/AE and tDCS sessions.

Perceived Ineffectiveness of Pharmacological Treatments for Dysmenorrhea

Background: Dysmenorrhea affects most reproductive-aged women. Common dysmenorrhea treatments vary in their effectiveness across individuals. Little is known about factors associated with perceived treatment ineffectiveness. The objectives of this study were to describe the perceived ineffectiveness of common pharmacological treatments for dysmenorrhea and investigate factors associated with perceived treatment ineffectiveness. Materials and Methods: In this cross-sectional study, 678 women with dysmenorrhea (aged 14-42) provided data on perceived treatment ineffectiveness, dysmenorrhea symptom-based phenotypes, demographics, clinical factors, and psychobehavioral characteristics. We used Fisher's exact tests to compare treatment ineffectiveness across three symptom-based phenotypes. We used logistic regressions to explore associations of phenotype, demographic, clinical, and psychobehavioral correlates of perceived treatment ineffectiveness. Results: Percentages perceiving treatments as ineffective were 29.3%-35.6% nonsteroidal anti-inflammatory drugs, 49.9% acetaminophen, and 39.3% combined oral contraceptive pills (OCPs). Factors associated with perceived ineffectiveness varied across treatments and included symptom-based phenotypes, clinical, and psychobehavioral factors. For ibuprofen and acetaminophen, women with severe (vs. mild) pain phenotype and higher number of chronic pain conditions were more likely to perceive the treatments as ineffective. For OCPs, women with severe pain (vs. mild) phenotype, comorbid gynecological condition, less anxiety, and worse depressive symptoms were more likely to perceive the treatment as ineffective. Conclusion: A significant percentage of women reported ineffectiveness of dysmenorrhea treatments. Phenotypes, clinical, and psychobehavioral factors were associated with treatment ineffectiveness. Future research should test if symptom-based phenotypes are associated with treatment effectiveness in clinical trials and investigate other factors that affect dysmenorrhea treatment effectiveness, so treatments can be tailored to individuals.

Changes in prefrontal cortex activation with exercise in knee osteoarthritis patients with chronic pain: An fNIRS study

The role of exercise on pain modulatory mechanism of the prefrontal areas is not clear. We aimed to determine the effects of exercise on functional activity of the prefrontal cortex in patients with knee osteoarthritis (OA) with chronic pain and to assess the relationships between changes in clinical variables and cortical hemodynamics with exercise via functional near-infrared spectroscopy (fNIRS). Fifteen patients with knee OA with chronic pain were included. All participants attended an exercise program 3 times a week for 6 weeks. Pain during activity was assessed by visual analogue scale (VAS). Pain catastrophization, kinesiophobia and functionality were also measured. Brain hemodynamic activity was assessed with a 47-channel fNIRS system before and after the exercise. Pain, pain catastrophization, kinesiophobia and functionality scores significantly improved (p < 0.05) while functional activity of the dorsolateral prefrontal cortex (DLPFC) during painful stimuli was significantly reduced after exercise program (p < 0.05). Change in cortical hemodynamic activity within the DLPFC was significantly correlated with change in pain perception (R = 0.54, p < 0.05) and pain catastrophization scores (R = 0.44, p < 0.05). Exercise resulted in improvements in clinical assessments of pain severity and pain catastrophization which was accompanied by alterations in prefrontal cortex activation. We provided evidence about the pain modulatory effects of exercise at cortical level which is correlated with clinical improvements in patients with chronic pain. We demonstrate the feasibility and potential of fNIRS methodology for i) elucidating the neural mechanisms underlying chronic and stimulus evoked pain, and ii) exploring the effect of treatment methods on brain functionality.

Nociceptive stress interferes with neural processing of cognitive stimuli in Gulf War Veterans with chronic musculoskeletal pain

AIMS

Disrupted cognition and chronic musculoskeletal pain (CMP) are prevalent experiences among Gulf War Veterans (GWV). A negative association between CMP and cognition (i.e., chronic pain-related cognitive interference) has been observed in some chronic pain populations but has not been evaluated in GWV. Additional research suggests that disrupted cognition in GWV with CMP may be exacerbated by stressing the nociceptive system. Therefore, we compared cognitive performance and related neural activity between CMP and healthy control (CO) GWV in the absence and presence of experimental pain.

MAIN METHODS

During functional magnetic resonance imaging (fMRI), Veterans (CMP = 29; CO = 27) completed cognitive testing via congruent and incongruent conditions of a modified Stroop task (Stroop-only). A random subset (CMP = 13; CO = 13) also completed cognitive testing with experimental pain (Pain+Stroop). Yuen's modified t-test and robust mixed-model analysis of variance (ANOVA) models were used for analyzing cognitive performance data. Independent t-tests and repeated-measures ANOVA models were employed for fMRI data with thresholding for multiple-comparisons (p < 0.005) and cluster size (> 320 mm³).

KEY FINDINGS

Functional MRI analysis revealed significant between-group differences for the incongruent but not congruent-Stroop run. Neither correct responses nor reaction time differed between groups in either Stroop condition (all p ≥ 0.21). Significant group (CMP, CO) by run (Stroop-only, Pain+Stroop) interactions revealed greater neural responses in CMP Veterans during Pain+Stroop runs. No significant interactions were observed for correct responses or reaction time (p ≥ 0.31).

SIGNIFICANCE

GWV with CMP require a greater amount of neural resources to sustain cognitive performance during nociceptive stress.

Altered functional connectivity between hypothalamus and limbic system in fibromyalgia

The hypothalamus links the nervous system to the endocrine system and plays a crucial role in maintaining the human body's homeostasis. This study aims to investigate the resting state functional connectivity (rsFC) changes of the hypothalamus in fibromyalgia patients. 24 Fibromyalgia patients and 24 matched healthy controls (HCs) were recruited. Resting state fMRI data were collected from the fibromyalgia patients and HC's. Fibromyalgia patients went through a second scan after 12 weeks of Tai Chi mind-body intervention. Data analysis showed that fibromyalgia patients displayed less medial hypothalamus (MH) rsFC with the thalamus and amygdala when compared to the functional connectivity in the HCs. After the Tai Chi mind-body intervention, fibromyalgia patients showed increased MH rsFC with the thalamus and amygdala accompanied by clinical improvement. Effective connectivity analysis showed disrupted MH and thalamus interaction in the fibromyalgia patients, which was altered by mind-body exercise. Our findings suggest that fibromyalgia is associated with altered functional connectivity within the diencephalon and limbic system. Elucidating the roles of the diencephalon and limbic system in the pathophysiology and development of fibromyalgia may facilitate the development of a new biomarker and effective treatment methods for this prevalent disorder.Trial Registration ClinicalTrials.gov, NCT02407665. Registered: 3 April 2015, https://clinicaltrials.gov/ct2/show/NCT02407665?term=NCT02407665&draw=2&rank=1.

Rotator cuff-related shoulder pain: does the type of exercise influence the outcomes? Protocol of a randomised controlled trial

INTRODUCTION

Lifetime prevalence of shoulder pain is 70%, and approximately 50% of people with shoulder pain will experience pain for more than a year. Rotator cuff-related shoulder pain (RCRSP) is the most common shoulder condition and the main non-surgical intervention is exercise therapy. For approximately 30% of people with RCRSP, this approach does not lead to a significant reduction in symptoms. This may be due to an inappropriate dosage or choice of exercises. The aim of this investigation is to compare the short, mid and long-term effects, in terms of symptoms, functional limitations, kinesiophobia and pain catastrophising, of three different shoulder rehabilitation approaches (education, strengthening, motor control) in adults with RCRSP.

METHODS AND ANALYSIS

In this single-blind (assessor), parallel-group, randomised clinical trial, 123 adults presenting with RCRSP will take part in a 12-week rehabilitation programme. They will be randomly assigned to one of three groups (education only, strengthening approach or motor control-focused approach). Abbreviated version of the Disabilities of the Arm, Shoulder and Hand Questionnaire, the primary outcome, Western Ontario Rotator Cuff Index and Brief Pain Inventory will evaluate symptoms and functional limitations, while Tampa Scale of Kinesiophobia and Pain Catastrophizing Scale will evaluate pain-related fear and catastrophising at baseline and at 3, 6, 12 and 24 weeks. Ultrasonographic acromiohumeral distances and tendon thickness will be assessed at baseline and 12 weeks. Intervention groups will be compared on outcomes with intention-to-treat analyses using two-way repeated measures analysis of variance if the data are normally distributed or non-parametric analysis of longitudinal data if they are not.

ETHICS AND DISSEMINATION

Ethics approval was obtained from the Sectorial Rehabilitation and Social Integration Research Ethics Committee of the Centre Intégré Universitaire de Santé et de Services Sociaux de la Capitale Nationale (CIUSSS-CN). Results will be disseminated through international publications in peer-reviewed journals, in addition to international conference presentations.

TRIAL REGISTRATION NUMBER

NCT03892603; pre-results.

Exercise-induced hypoalgesia after acute and regular exercise: experimental and clinical manifestations and possible mechanisms in individuals with and without pain

This review describes methodology used in the assessment of the manifestations of exercise-induced hypoalgesia in humans and previous findings in individuals with and without pain. Possible mechanisms and future directions are discussed.

Exercise and physical activity is recommended treatment for a wide range of chronic pain conditions. In addition to several well-documented effects on physical and mental health, 8 to 12 weeks of exercise therapy can induce clinically relevant reductions in pain. However, exercise can also induce hypoalgesia after as little as 1 session, which is commonly referred to as exercise-induced hypoalgesia (EIH). In this review, we give a brief introduction to the methodology used in the assessment of EIH in humans followed by an overview of the findings from previous experimental studies investigating the pain response after acute and regular exercise in pain-free individuals and in individuals with different chronic pain conditions. Finally, we discuss potential mechanisms underlying the change in pain after exercise in pain-free individuals and in individuals with different chronic pain conditions, and how this may have implications for clinical exercise prescription as well as for future studies on EIH.

Central neurobiological effects of physical exercise in individuals with chronic musculoskeletal pain: a systematic review

OBJECTIVE

Primary objectives: to investigate the central neurobiological effects (using MRI) of physical exercise in individuals with chronic pain. Secondary objectives: (1) to investigate the associations between central changes and clinical outcomes and (2) to investigate whether different types and dosages of physical exercise exert different central changes.

DESIGN

Systematic review searching four electronic databases up to September 2018: AMED, CINAHL, Embase and MEDLINE. Two reviewers independently assessed the methodological quality of included studies using the Cochrane Collaboration's Risk of Bias in Non-Randomised Studies-I tool. A standardised extraction table was used for data extraction, which was performed by two reviewers.

INTERVENTIONS

Studies reporting any physical exercise intervention in any chronic musculoskeletal pain condition were included. Eligibility of 4011 records was screened independently by two reviewers, and four studies were included in the review.

PRIMARY AND SECONDARY OUTCOME MEASURES

Primary outcome: any brain outcome assessed with any MR technique.

SECONDARY OUTCOMES

any self-reported clinical outcomes, and type and dosage of the exercise intervention.

RESULTS

All four studies had high risk of bias. There was heterogeneity between the brain areas studied and the types of exercise interventions delivered. All studies reported functional MRI changes in various brain areas following an exercise intervention. Insufficient data were available to conduct a meta-analysis or to answer the secondary aims.

CONCLUSIONS

Only a limited number of studies were available and all were at high risk of bias. None of the studies was randomised or included blinded assessment. Exercise may exert effects on brain neurobiology in people with chronic pain. Due to the high risk of bias, future studies should use a randomised study design. Investigation of morphological brain changes could be included.

PROSPERO REGISTRATION NUMBER

CRD42018108179.

Optimised transcranial direct current stimulation (tDCS) for fibromyalgia-targeting the endogenous pain control system: a randomised, double-blind, factorial clinical trial protocol

INTRODUCTION

Fibromyalgia (FM) is a common debilitating condition with limited therapeutic options. Medications have low efficacy and are often associated with adverse effects. Given that FM is associated with a defective endogenous pain control system and central sensitisation, combining interventions such as transcranial direct current stimulation (tDCS) and aerobic exercise (AE) to modulate pain-processing circuits may enhance pain control.

METHODS AND ANALYSIS

A prospective, randomised (1:1:1:1), placebo-controlled, double-blind, factorial clinical trial will test the hypothesis that optimised tDCS (16 anodal tDCS sessions combined with AE) can restore of the pain endogenous control system. Participants with FM (n=148) will undergo a conditioning exercise period and be randomly allocated to one of four groups: (1) active tDCS and AE, (2) sham tDCS and AE, (3) active tDCS and non-aerobic exercise (nAE) or (4) sham tDCS and nAE. Pain inhibitory activity will be assessed using conditioned pain modulation (CPM) and temporal slow pain summation (TSPS)-primary outcomes. Secondary outcomes will include the following assessments: Transcranial magnetic stimulation and electroencephalography as cortical markers of pain inhibitory control and thalamocortical circuits; secondary clinical outcomes on pain, FM, quality of life, sleep and depression. Finally, the relationship between the two main mechanistic targets in this study-CPM and TSPS-and changes in secondary clinical outcomes will be tested. The change in the primary efficacy endpoint, CPM and TSPS, from baseline to week 4 of stimulation will be tested with a mixed linear model and adjusted for important demographic variables.

ETHICS AND DISSEMINATION

This study obeys the Declaration of Helsinki and was approved by the Institutional Review Board (IRB) of Partners Healthcare under the protocol number 2017P002524. Informed consent will be obtained from participants. Study findings will be reported in conferences and peer-reviewed journal publications.

TRIAL REGISTRATION NUMBER

NCT03371225.

Influence of pain anticipation on brain activity and pain perception in Gulf War Veterans with chronic musculoskeletal pain

Anticipation of a painful experience can influence brain activity and increase sensitivity to experimental somatosensory stimuli in healthy adults, but this response is poorly understood among individuals with chronic musculoskeletal pain (CMP). Studies of brain and perceptual responses to somatosensory stimuli are used to make inferences about central nervous system dysfunction as a potential mechanism of symptoms. As such, we sought to (a) determine the influence of pain anticipation on pain-relevant brain regions and pain perception, and (b) characterize potential differences in these responses between Gulf War Veterans with CMP and matched healthy control (CO) Veterans. CMP (N = 30) and CO Veterans (N = 31) were randomized to conditions designed to generate expectations that either painful (pain) or nonpainful (no pain) stimuli would be administered. Brain responses to five nonpainful thermal stimuli were measured during fMRI, and each stimulus was rated for pain intensity and unpleasantness. In the pain condition, an incremental linear decrease in activity across stimuli was observed in the posterior cingulate cortex, cingulate cortex, and middle temporal gyrus. Further, in the pain condition, differential responses were observed between CMP and CO Veterans in the middle temporal gyrus. These findings indicate that brain responses to nonpainful thermal stimuli in Veterans with CMP are sensitive to pain anticipation, and we recommend accounting for the influence of pain anticipation in future investigations of central nervous system dysfunction in CMP.

Catastrophizing Interferes with Cognitive Modulation of Pain in Women with Fibromyalgia

Background

Pain modulation is a critical function of the nociceptive system that includes the ability to engage descending pain control systems to maintain a functional balance between facilitation and inhibition of incoming sensory stimuli. Dysfunctional pain modulation is associated with increased risk for chronic pain and is characteristic of fibromyalgia (FM). Catastrophizing is also common in FM. However, its influence on pain modulation is poorly understood.

Objective

To determine the role of catastrophizing on central nervous system processing during pain modulation in FM via examining brain responses and pain sensitivity during an attention-distraction paradigm.

Methods

Twenty FM patients and 18 healthy controls (CO) underwent functional magnetic resonance imaging while receiving pain stimuli, administered alone and during distracting cognitive tasks. Pain ratings were assessed after each stimulus. Catastrophizing was assessed with the Pain Catastrophizing Scale (PCS).

Results

The ability to modulate pain during distraction varied among FM patients and was associated with catastrophizing. This was demonstrated by significant positive relationships between PCS scores and pain ratings (P < 0.05) and brain responses in the dorsolateral prefrontal cortex (P < 0.01). Relationships between catastrophizing and pain modulation did not differ between FM and CO (P > 0.05).

Conclusions

FM patients with higher levels of catastrophizing were less able to distract themselves from pain, indicative of catastrophizing-related impairments in pain modulation. These results suggest that the tendency to catastrophize interacts with attention-resource allocation and may represent a mechanism of chronic pain exacerbation and/or maintenance. Reducing catastrophizing may improve FM symptoms via improving central nervous system regulation of pain.

Modulatory effects of different exercise modalities on the functional connectivity of the periaqueductal grey and ventral tegmental area in patients with knee osteoarthritis: a randomised multimodal magnetic resonance imaging study

BACKGROUND

Knee osteoarthritis is a prevalent disorder with unsatisfactory treatment options. Both physical and mindful exercises may be able to relieve its pain symptoms. We compared the modulatory effects of different exercise modalities on the periaqueductal grey (PAG) and ventral tegmental area (VTA), which play important roles in descending opioidergic pathways and reward/motivation systems in patients with knee osteoarthritis.

METHODS

We recruited and randomised 140 patients into Tai Chi, Baduanjin, stationary cycling, and health education control groups for 12 weeks. Knee injury and Osteoarthritis Outcome Score (KOOS), functional and structural MRI, and blood biomarkers were measured at the beginning and end of the experiment. We used the PAG and VTA as seeds in resting-state functional connectivity (rsFC) analysis.

RESULTS

Compared with the control group: (i) all exercises significantly increased KOOS pain sub-scores (pain reduction) and serum programmed death 1 (PD-1) concentrations; (ii) all exercises decreased right PAG rsFC with the medial orbital prefrontal cortex, and the decreased rsFC was associated with improvements in knee pain; and (iii) grey matter volume in the medial orbital prefrontal cortex was significantly increased in all exercise groups. There was also significantly decreased rsFC between the left VTA and the medial orbital prefrontal cortex in the Tai Chi and Baduanjin groups.

CONCLUSIONS

Exercise can simultaneously modulate the rsFC of the descending opioidergic pathway and reward/motivation system and blood inflammation markers. Elucidating the shared and unique mechanisms of different exercise modalities may facilitate the development of exercise-based interventions for chronic pain.

CLINICAL TRIAL REGISTRATION

ChiCTR-IOR-16009308.

Altered resting state functional connectivity of the cognitive control network in fibromyalgia and the modulation effect of mind-body intervention

This study examines altered resting state functional connectivity (rsFC) of the cognitive control network (CCN) in fibromyalgia patients as compared to healthy controls, as well as how an effective mind-body intervention, Tai Chi, can modulate the altered rsFC of the CCN. Patients with fibromyalgia and matched healthy subjects were recruited in this study. Fibromyalgia patients were scanned 12 weeks before and after intervention. The bilateral dorsolateral prefrontal cortex (DLPFC) was used as a seed to explore the rsFC of the CCN. Data analysis was conducted with 21 patients and 20 healthy subjects. Compared to healthy subjects, fibromyalgia patients exhibited increased rsFC between the DLPFC and the bilateral rostral anterior cingulate cortex (rACC) and medial prefrontal cortex (MPFC) at baseline. The rsFC between the CCN and rACC/MPFC further increased after Tai Chi intervention, and this increase was accompanied by clinical improvements. This rsFC change was also significantly associated with corresponding changes in the Overall Impact domain of the Revised Fibromyalgia Impact Questionnaire (FIQR). Further analysis showed that the rACC/MPFC rsFC with both the PAG and hippocampus significantly decreased following Tai Chi intervention. Our study suggests that fibromyalgia is associated with altered CCN rsFC and that effective mind-body treatment may elicit clinical improvements by further increasing this altered rsFC. Elucidating this mechanism of enhancing the allostasis process will deepen our understanding of the mechanisms underlying mind-body interventions in fibromyalgia patients and facilitate the development of new pain management methods.

Interleukin-4 mediates the analgesia produced by low-intensity exercise in mice with neuropathic pain

Peripheral nerve injury (PNI) activates the immune system, resulting in increased proinflammatory cytokines at the site of injury and in the spinal cord dorsal horn. Exercise modulates the immune system promoting an anti-inflammatory phenotype of macrophages in uninjured muscle, and increases in anti-inflammatory cytokines can promote healing and analgesia. We proposed that PNI will decrease, and treadmill exercise will increase, release of anti-inflammatory cytokines at the site of injury and in the spinal cord. We show that 2 weeks of treadmill exercise improves neuropathic pain behaviors in mice: mechanical hyperalgesia, escape and avoidance behavior, and spontaneous locomotor activity. Peripheral nerve injury reduced anti-inflammatory cytokines (interleukin-4 [IL-4], IL-1ra, and IL-5) at the site of nerve injury and in the spinal dorsal horn, whereas exercise restored IL-4, IL-1ra, and IL-5 concentrations to preinjury levels. IL4 mice and mice treated with IL-4 antibody did not develop analgesia to treadmill exercise. Using immunohistochemical staining of the sciatic nerve, treadmill exercise increased the percentage of M2 macrophages (secretes anti-inflammatory cytokines) and decreased M1 macrophages (secretes proinflammatory cytokines) when compared with sedentary mice. The increased M2 and decreased M1 macrophages in exercised mice did not occur in IL-4 mice. In the spinal cord, PNI increased glial cell activation, brain-derived neurotrophic factor and β-nerve growth factor levels, and decreased IL-4 and IL-1ra levels, whereas treadmill exercise suppressed glial cells activation (Glial Fibrillary Acidic Protein and Iba1 immunoreactivity), reduced brain-derived neurotrophic factor and β-nerve growth factor, and increased IL-4, IL-1ra, and IL-5 concentrations. Our results suggest that IL-4 mediates the analgesia produced by low-intensity exercise by modulating peripheral and central neuroimmune responses in mice with neuropathic pain.

Potential Nervous System Sensitization in Patients With Persistent Lower Extremity Tendinopathies: 3 Case Reports

BACKGROUND

Tendinopathy is a condition often associated with pain and functional and sport performance limitations. While targeted exercise prescriptions are often effective, many patients with tendinopathy develop persistent symptoms. Emerging evidence suggests a possible link between nervous system sensitization and tendinopathy. If so, identifying and treating specific pain mechanisms may improve outcomes.

CASE DESCRIPTION

Three patients were seen in physical therapy for complaints of ongoing chronic tendon pain and self-reported disability, despite being treated previously and receiving evidence-informed care. Upon examination, each patient demonstrated signs consistent with possible dysfunction of central pain mechanisms. Joint mobilization, pain neuroscience education, and aerobic exercise were primary interventions in each case to decrease pain and improve function.

OUTCOMES

The 3 patients were treated for 5 sessions over the course of 8 weeks. Clinically significant improvement was noted in measures of pain, self-reported function, and pressure pain thresholds. At discharge, all patients were able to run without symptoms, and improvement was maintained at 1-year follow-up.

DISCUSSION

Tendinopathy, while often described as local pain and dysfunction, may be associated with dysfunction of the nervous system. Identifying and treating pain mechanisms in addition to relevant impairments may be an appropriate intervention approach for individuals with tendinopathy.

LEVEL OF EVIDENCE

Therapy, level 4. J Orthop Sports Phys Ther 2019;49(4):272-279. Epub 13 Feb 2019. doi:10.2519/jospt.2019.8600.

Developing an optimized strategy with transcranial direct current stimulation to enhance the endogenous pain control system in fibromyalgia

INTRODUCTION

Fibromyalgia affects more than 5 million people in the United States and has a detrimental impact on individuals' quality of life. Current pharmacological treatments provide limited benefits to relieve the pain of fibromyalgia, along with a risk of adverse effects; a scenario that explains the increasing interest for multimodal approaches. A tailored strategy to focus on this dysfunctional endogenous pain inhibitory system is transcranial direct current stimulation (tDCS) of the primary motor cortex. By combining tDCS with aerobic exercise, the effects can be optimized. Areas covered: The relevant literature was reviewed and discussed the methodological issues for designing a mechanistic clinical trial to test this combined intervention. Also, we reviewed the neural control of different pathways that integrate the endogenous pain inhibitory system, as well as the effects of tDCS and aerobic exercise both alone and combined. In addition, potential neurophysiological assessments are addressed: conditioned pain modulation, temporal slow pain summation, transcranial magnetic stimulation, and electroencephalography in the context of fibromyalgia. Expert commentary: By understanding the neural mechanisms underlying pain processing and potential optimized interventions in fibromyalgia with higher accuracy, the field has an evident potential of advancement in the direction of new neuromarkers and tailored therapies.

Prescribed Versus Preferred Intensity Resistance Exercise in Fibromyalgia Pain

Exercise is the treatment of choice for fibromyalgia (FM), but little is known about resistance exercise prescription to modulate pain in this condition. This study aimed to compare the effects of different resistance exercise models, comprising self-selected or prescribed intensity, on pain in FM patients. In a cross-over fashion, 32 patients underwent the following sessions: (i) standard prescription (STD; 3 × 10 repetitions at 60% of maximal strength); (ii) self-selected load with fixed number of repetitions (SS); (iii) self-selected load with volume load (i.e., load × sets × repetitions) matched for STD (SS-VM); and (iv) self-selected load with a free number of repetitions until achieving score 7 of rating perceived exertion (SS-RPE). Pain, assessed by Visual Analogic Scale (VAS) and Short-Form McGill Pain Questionnaire (SF-MPQ), was evaluated before and 0, 24, 48, 72, and 96 h after the sessions. Load was significantly lower in SS, SS-VM, SS-RPE than in STD, whereas rating perceived exertion and volume load were comparable between sessions. VAS scores increased immediately after all sessions (p < 0.0001), and reduced after 48, 72, 96 h (p < 0.0001), remaining elevated compared to pre-values. SF-MPQ scores increased immediately after all exercise sessions (p = 0.025), then gradually reduced across time, reaching baseline levels at 24 h. No significant differences between sessions were observed. Both prescribed and preferred intensity resistance exercises failed in reducing pain in FM patients. The recommendation that FM patients should exercise at preferred intensities to avoid exacerbated pain, which appears to be valid for aerobic exercise, does not apply to resistance exercise.

Role of the Prefrontal Cortex in Pain Processing

The prefrontal cortex (PFC) is not only important in executive functions, but also pain processing. The latter is dependent on its connections to other areas of the cerebral neocortex, hippocampus, periaqueductal gray (PAG), thalamus, amygdala, and basal nuclei. Changes in neurotransmitters, gene expression, glial cells, and neuroinflammation occur in the PFC during acute and chronic pain, that result in alterations to its structure, activity, and connectivity. The medial PFC (mPFC) could serve dual, opposing roles in pain: (1) it mediates antinociceptive effects, due to its connections with other cortical areas, and as the main source of cortical afferents to the PAG for modulation of pain. This is a ‘loop’ where, on one side, a sensory stimulus is transformed into a perceptual signal through high brain processing activity, and perceptual activity is then utilized to control the flow of afferent sensory stimuli at their entrance (dorsal horn) to the CNS. (2) It could induce pain chronification via its corticostriatal projection, possibly depending on the level of dopamine receptor activation (or lack of) in the ventral tegmental area-nucleus accumbens reward pathway. The PFC is involved in biopsychosocial pain management. This includes repetitive transcranial magnetic stimulation, transcranial direct current stimulation, antidepressants, acupuncture, cognitive behavioral therapy, mindfulness, music, exercise, partner support, empathy, meditation, and prayer. Studies demonstrate the role of the PFC during placebo analgesia, and in establishing links between pain and depression, anxiety, and loss of cognition. In particular, losses in PFC grey matter are often reversible after successful treatment of chronic pain.

Breathing Exercises Must Be a Real and Effective Intervention to Consider in Women with Fibromyalgia: A Pilot Randomized Controlled Trial

BACKGROUND/OBJECTIVE

Respiratory problems can aggravate pain located in the coincident areas with tender points in the upper half of the body in patients with fibromyalgia (FM) and easily become fatigued, thus can lead to a decrease in the functionality of daily activities. The purpose of this study was to examine the effects of a breathing exercises program on pain thresholds tolerance on tender points and FM impact on daily life.

METHODS/DESIGN

Thirty-five women with FM (age 34-67 years) were randomly assigned to an exercise group (n = 18), performing breathing exercises (30 min/session, 7 times/week; for 12 weeks), or to a control group (n = 17). Pain thresholds tolerance on tender points were measured by the physician using digital pressure algometer and FM impact on daily life was evaluated with the Portuguese version of the Fibromyalgia Impact Questionnaire (FIQ).

RESULTS

After 12 weeks of breathing exercises significant improvements were observed in the mean values of the treatment effects on pain thresholds tolerance on tender points and in the functional capacity to perform daily life, pain, and fatigue in favor of the exercise group. Gains in second rib, occiput, and supraspinatus pairs of the tender points predict improvements in the functional capacity, pain, and fatigue.

CONCLUSION

Our study demonstrated that breathing exercises produced relevant benefits on pain thresholds tolerance on tender points located in the upper half of the body, some of which predicted improvements in the impact of FM in the functional capacity to perform daily life, pain, and fatigue. These results provide further support of an idea that breathing exercises are a real and effective intervention to consider in women with FM.

TRIAL REGISTRATION

International Standard Randomized Controlled Trial Number ISRCTN37081460, available information in www.isrctn.com/ ISRCTN37081460.

Identification of candidate genes associated with fibromyalgia susceptibility in southern Spanish women: the al-Ándalus project

BACKGROUND

Candidate-gene studies on fibromyalgia susceptibility often include a small number of single nucleotide polymorphisms (SNPs), which is a limitation. Moreover, there is a paucity of evidence in Europe. Therefore, we compared genotype frequencies of candidate SNPs in a well-characterised sample of Spanish women with fibromyalgia and healthy non-fibromyalgia women.

METHODS

A total of 314 women with a diagnosis of fibromyalgia (cases) and 112 non-fibromyalgia healthy (controls) women participated in this candidate-gene study. Buccal swabs were collected for DNA extraction. Using TaqMan™ OpenArray™, we analysed 61 SNPs of 33 genes related to fibromyalgia susceptibility, symptoms, or potential mechanisms.

RESULTS

We observed that the rs841 and rs1799971 GG genotype was more frequently observed in fibromyalgia than in controls (p = 0.04 and p = 0.02, respectively). The rs2097903 AT/TT genotypes were also more often present in the fibromyalgia participants than in their control peers (p = 0.04). There were no differences for the remaining SNPs.

CONCLUSIONS

We identified, for the first time, associations of the rs841 (guanosine triphosphate cyclohydrolase 1 gene) and rs2097903 (catechol-O-methyltransferase gene) SNPs with higher risk of fibromyalgia susceptibility. We also confirmed that the rs1799971 SNP (opioid receptor μ1 gene) might confer genetic risk of fibromyalgia. We did not adjust for multiple comparisons, which would be too stringent and yield to non-significant differences in the genotype frequencies between cases and controls. Our findings may be biologically meaningful and informative, and should be further investigated in other populations. Of particular interest is to replicate the present study in a larger independent sample to confirm or refute our findings. On the other hand, by including 61 SNPs of 33 candidate-genes with a strong rationale (they were previously investigated in relation to fibromyalgia susceptibility, symptoms or potential mechanisms), the present research is the most comprehensive candidate-gene study on fibromyalgia susceptibility to date.

Potential Mechanisms Underlying Centralized Pain and Emerging Therapeutic Interventions

Centralized pain syndromes are associated with changes within the central nervous system that amplify peripheral input and/or generate the perception of pain in the absence of a noxious stimulus. Examples of idiopathic functional disorders that are often categorized as centralized pain syndromes include fibromyalgia, chronic pelvic pain syndromes, migraine, and temporomandibular disorder. Patients often suffer from widespread pain, associated with more than one specific syndrome, and report fatigue, mood and sleep disturbances, and poor quality of life. The high degree of symptom comorbidity and a lack of definitive underlying etiology make these syndromes notoriously difficult to treat. The main purpose of this review article is to discuss potential mechanisms of centrally-driven pain amplification and how they may contribute to increased comorbidity, poorer pain outcomes, and decreased quality of life in patients diagnosed with centralized pain syndromes, as well as discuss emerging non-pharmacological therapies that improve symptomology associated with these syndromes. Abnormal regulation and output of the hypothalamic-pituitary-adrenal (HPA) axis is commonly associated with centralized pain disorders. The HPA axis is the primary stress response system and its activation results in downstream production of cortisol and a dampening of the immune response. Patients with centralized pain syndromes often present with hyper- or hypocortisolism and evidence of altered downstream signaling from the HPA axis including increased Mast cell (MC) infiltration and activation, which can lead to sensitization of nearby nociceptive afferents. Increased peripheral input via nociceptor activation can lead to “hyperalgesic priming” and/or “wind-up” and eventually to central sensitization through long term potentiation in the central nervous system. Other evidence of central modifications has been observed through brain imaging studies of functional connectivity and magnetic resonance spectroscopy and are shown to contribute to the widespreadness of pain and poor mood in patients with fibromyalgia and chronic urological pain. Non-pharmacological therapeutics, including exercise and cognitive behavioral therapy (CBT), have shown great promise in treating symptoms of centralized pain.

Severity of symptoms persists for decades in fibromyalgia-a 26-year follow-up study

The aim of this study is to find out the outcome of 28 patients who got the diagnosis of primary fibromyalgia (pFM) 26 years ago. In 1986, 56 patients with widespread pain were examined and filled in a base questionnaire (BQ). Of them, 42 fulfilled the Yunus criteria for pFM. Twenty-six years later, addresses of 38 patients were found, and an extensive follow-up questionnaire (FupQ) was mailed to them. Of them, 28 (74%) answered the FupQ. This included nine identical questions with the BQ and questions concerning changes in their symptoms and quality of life (Qol). Three patients (11%) had healed from fibromyalgia (FM), and 23% reported having one or several symptomless periods lasting at least 1 year. In others (n = 25), all but pain and ache showed slight deterioration. Despite the aging and FM, the level of functional ability evaluated by Stanford Health Assessment Questionnaire (HAQ) remained at the same level (BQ 0.41 vs. Fup 0.44, p = 0.82). The sum score of reported symptoms (n = 21) did not change significantly (10.8 (SD 2.9) vs. 11.1 (SD 4.1), p = 0.75). Experienced sleeplessness increased most significantly (27 vs. 65%, p = 0.0034). Exercising did not have a significant influence on the changes of the measured parameters. However, the three healed patients exercised regularly. Symptoms of FM have persisted in most patients for decades without significant deterioration of self-reported functional ability. About one fourth of patients had experienced long symptomless periods during their illness. Three patients (11%) reported that they have healed from FM.

Nonpharmacological Interventions in Targeting Pain-Related Brain Plasticity

Chronic pain is a highly prevalent and debilitating condition that is frequently associated with multiple comorbid psychiatric conditions and functional, biochemical, and anatomical alterations in various brain centers. Due to its widespread and diverse manifestations, chronic pain is often resistant to classical pharmacological treatment paradigms, prompting the search for alternative treatment approaches that are safe and efficacious. The current review will focus on the following themes: attentional and cognitive interventions, the role of global environmental factors, and the effects of exercise and physical rehabilitation in both chronic pain patients and preclinical pain models. The manuscript will discuss not only the analgesic efficacy of these therapies, but also their ability to reverse pain-related brain neuroplasticity. Finally, we will discuss the potential mechanisms of action for each of the interventions.

The discordance between subjectively and objectively measured physical function in women with fibromyalgia: association with catastrophizing and self-efficacy cognitions. The al-Ándalus project

PURPOSE

People with fibromyalgia experience a disagreement between patient-reported (i.e., subjective) and performance-based (i.e., objective) status. This study aimed to (i) corroborate the discordance between subjectively and objectively measured physical function and (ii) examine whether catastrophizing (worrying, pain magnifying, and helpless cognitions) and self-efficacy (believing capable to manage pain) are independently associated with this discordance.

METHODS

This population-based cross-sectional study included 405 women with fibromyalgia and 193 age-matched female controls. Participants completed the Pain Catastrophizing Scale, Chronic Pain Self-efficacy Scale, and physical functioning subscales of the Revised Fibromyalgia Impact Questionnaire and Short Form-36 (SF-36) health survey. Objective physical function was measured with the Senior Fitness Test battery. Subjective and objective physical functions were expressed as deviation from the general population in standard deviation (SD) units using means and SD of the control group.

RESULTS

In fibromyalgia, subjective physical function was worse than objective physical function (p < 0.001). Higher catastrophizing was consistently associated with greater discordance between subjective and objective physical function, while self-efficacy was only significantly associated with this discordance when subjective physical function was assessed by means of the SF-36.

CONCLUSIONS

Subjective physical function is more impaired than objective physical function in fibromyalgia, yet both are markedly impaired. Catastrophizing cognitions are associated with this discordance. In particular, high catastrophizing may promote a feeling of reduced ability to do meaningful activities of daily living (i.e., restrictions) that people with fibromyalgia are actually able to. Therefore, catastrophizing should be assessed and potentially targeted when focusing on improving physical function in fibromyalgia. Implications for rehabilitation Rehabilitation should focus on physical exercise programs to help women with fibromyalgia to improve their reduced physical function. In rehabilitation settings, physical function of people with fibromyalgia should be evaluated by both subjective and objective assessments to fully understand physical functioning and to test the existence of discordance between both assessments. In case of a large discordance between subjective and objective physical function, a physical exercise program might be better complemented with cognitive management techniques to reduce catastrophizing and subjective physical dysfunction. When people with fibromyalgia experience high levels of catastrophizing, subjective assessments seem to be poor indicators of physical function.