Physical activity based on daily steps in patients with chronic musculoskeletal pain: evolution and associated factors.

BACKGROUND: People with chronic musculoskeletal pain (CMSP) often have low physical activity. Various factors can influence the activity level. The aim of this study was to monitor physical activity, assessed by the number of steps per day, over time in people with CMSP and identify factors that could be associated with this activity feature. METHODS: This prospective study involved people undergoing rehabilitation following an orthopedic trauma that had led to CMSP. At entry, participants completed self-reported questionnaires assessing pain, anxiety, depression, catastrophyzing, kinesiophobia, and behavioural activity patterns (avoidance, pacing and overdoing). They also underwent functional tests, assessing walking endurance and physical fitness. To determine daily step counts, participants wore an accelerometer for 1 week during rehabilitation and 3 months post-rehabilitation. The number of steps per day was compared among three time points: weekend of rehabilitation (an estimate of pre-rehabilitation activity; T1), weekdays of rehabilitation (T2), and post-rehabilitation (T3). Linear regression models were used to analyze the association between daily steps at T2 and at T3 and self-reported and performance-based parameters. RESULTS: Data from 145 participants were analyzed. The mean number of steps was significantly higher during T2 than T1 and T3 (7323 [3047] vs. 4782 [2689], p < 0.001, Cohen's d = 0.769, and 4757 [2680], p < 0.001, Cohen's d = 0.693), whereas T1 and T3 results were similar (p = 0.92, Cohen's d = 0.008). Correlations of number of steps per day among time points were low (r ≤ 0.4). Multivariable regression models revealed an association between daily steps at T2 and pain interfering with walking, anxiety and overdoing behaviour. Daily steps at T3 were associated with overdoing behaviour and physical fitness. CONCLUSIONS: Despite chronic pain, people in rehabilitation after an orthopedic trauma increased their physical activity if they were given incentives to do so. When these incentives disappeared, most people returned to their previous activity levels. A multimodal follow-up approach could include both therapeutic and environmental incentives to help maintain physical activity in this population.

Agreement between child self-report and parent-proxy report for functioning in pediatric chronic pain.

PURPOSE: Accurate assessment of chronic pain and functional disability in children and adolescents is imperative for guiding pain management interventions. Parents have multifaceted roles in their child's pain experience and frequently provide parent-proxy reports of pain-related functioning. However, cross-informant variance is often observed with limited understanding of contributing factors. This study aims to examine the degree of alignment between child and parent-proxy reports for Patient-Reported Outcomes Measurement Information System (PROMIS) pain interference domain among children with chronic pain and to identify factors associated with improved child-parent agreement. METHODS: This study includes a sample of 127 youth (66.1% female) with mixed etiology chronic pain, ranging in age from 8 to 17 (M = 12.24; SD = 1.598), and their parent. Data was collected at an interdisciplinary pediatric pain clinic and online peer support groups. Measures of demographic, pain intensity, and functioning were collected. RESULTS: Means of parent-proxy reports were significantly lower than child self-reports on the PROMIS (p < 0.05). A statistically significant association between child's pain intensity (ß = 0.953, P < 0.05) and the difference between child self-reported and parent-proxy reported PROMIS functional interference scores was found. CONCLUSION: Parents underestimated pain-related functional disability relative to children's self-reports. The difference between the paired child self-report and parent-proxy report of functional disability was significantly associated with greater child self-reported pain intensity. Although parent-proxy reports in pediatric chronic pain is often used in research and practice, findings underscore the importance of incorporating child and adolescent self-report, when possible, to comprehensively capture the child's pain experience and best inform clinical interventions.

Neuropathic pain has sex-specific effects on oxycodone-seeking and non-drug-seeking ensemble neurons in the dorsomedial prefrontal cortex of mice.

Approximately 50 million Americans suffer from chronic pain, and nearly a quarter of chronic pain patients have reported misusing opioid prescriptions. Repeated drug seeking is associated with reactivation of an ensemble of neurons sparsely scattered throughout the dorsomedial prefrontal cortex (dmPFC). Prior research has demonstrated that chronic pain increases intrinsic excitability of dmPFC neurons, which may increase the likelihood of reactivation during drug seeking. We tested the hypothesis that chronic pain would increase oxycodone-seeking behaviour and that the pain state would differentially increase intrinsic excitability in dmPFC drug-seeking ensemble neurons. TetTag mice self-administered intravenous oxycodone. After 7 days of forced abstinence, a drug-seeking session was performed, and the ensemble was tagged. Mice received spared nerve injury (SNI) to induce chronic pain during the period between the first and second seeking session. Following the second seeking session, we performed electrophysiology on individual neurons within the dmPFC to assess intrinsic excitability of the drug-seeking ensemble and non-ensemble neurons. SNI had no impact on sucrose seeking or intrinsic excitability of dmPFC neurons from these mice. In females, SNI increased oxycodone seeking and intrinsic excitability of non-ensemble neurons. In males, SNI had no impact on oxycodone seeking or neuron excitability. Data from females are consistent with clinical reports that chronic pain can promote drug craving and relapse and support the hypothesis that chronic pain itself may lead to neuroadaptations which promote opioid seeking.

Goniometry and fleximetry measurements to assess cervical range of motion in individuals with chronic neck pain: a validity and reliability study.

PURPOSE: To assess the test-retest and inter-rater reliability of goniometry and fleximetry in measuring cervical range of motion in individuals with chronic neck pain. METHODS: A reliability study. Thirty individuals with chronic neck pain were selected. Cervical range of motion was measured by goniometry and fleximetry at two time points 7 days apart. To characterize the sample, we used the numerical pain rating scale, Pain-Related Catastrophizing Thoughts Scale, and Neck Disability Index. Intraclass correlation coefficient (ICC), standard error of measurement (SEM) and minimum detectable change (MDC) were calculated. Correlations between goniometry and fleximetry measurements were performed using Spearman's correlation coefficient (rho). RESULTS: For goniometry, we found excellent test-retest reliability (ICC ≥ 0.986, SEM ≤ 1.89%, MDC ≤ 5.23%) and inter-rater reliability (ICC ≥ 0.947, SEM ≤ 3.91%, MDC ≤ 10.84%). Similarly, we found excellent test-retest reliability (ICC ≥ 0.969, SEM ≤ 2.71%, MDC ≤ 7.52%) and inter-rater reliability (ICC ≥ 0.981, SEM ≤ 1.88%, MDC ≤ 5.20%) for fleximetry. Finally, we observed a strong correlation between the goniometry and the fleximetry for all cervical movements (rho ≥ 0.993). CONCLUSION: Goniometry and fleximetry measurements are reliable for assessing cervical range of motion in individuals with chronic neck pain.

Resting-state brain activity as a biomarker of chronic pain impairment and a mediator of its association with pain resilience.

Past cross-sectional chronic pain studies have revealed aberrant resting-state brain activity in regions involved in pain processing and affect regulation. However, there is a paucity of longitudinal research examining links of resting-state activity and pain resilience with changes in chronic pain outcomes over time. In this prospective study, we assessed the status of baseline (T1) resting-state brain activity as a biomarker of later impairment from chronic pain and a mediator of the relation between pain resilience and impairment at follow-up. One hundred forty-two adults with chronic musculoskeletal pain completed a T1 assessment comprising a resting-state functional magnetic resonance imaging scan based on regional homogeneity (ReHo) and self-report measures of demographics, pain characteristics, psychological status, pain resilience, pain severity, and pain impairment. Subsequently, pain impairment was reassessed at a 6-month follow-up (T2). Hierarchical multiple regression and mediation analyses assessed relations of T1 ReHo and pain resilience scores with changes in pain impairment. Higher T1 ReHo values in the right caudate nucleus were associated with increased pain impairment at T2, after controlling for all other statistically significant self-report measures. ReHo also partially mediated associations of T1 pain resilience dimensions with T2 pain impairment. T1 right caudate nucleus ReHo emerged as a possible biomarker of later impairment from chronic musculoskeletal pain and a neural mechanism that may help to explain why pain resilience is related to lower levels of later chronic pain impairment. Findings provide empirical foundations for prospective extensions that assess the status of ReHo activity and self-reported pain resilience as markers for later impairment from chronic pain and targets for interventions to reduce impairment. PRACTITIONER POINTS: Resting-state markers of impairment: Higher baseline (T1) regional homogeneity (ReHo) values, localized in the right caudate nucleus, were associated with exacerbations in impairment from chronic musculoskeletal pain at a 6-month follow-up, independent of T1 demographics, pain experiences, and psychological factors. Mediating role of ReHo values: ReHo values in the right caudate nucleus also mediated the relationship between baseline pain resilience levels and later pain impairment among participants. Therapeutic implications: Findings provide empirical foundations for research extensions that evaluate (1) the use of resting-state activity in assessment to identify people at risk for later impairment from pain and (2) changes in resting-state activity as biomarkers for the efficacy of treatments designed to improve resilience and reduce impairment among those in need.

A model linking emotional dysregulation in neurodivergent people to the proprioceptive impact of joint hypermobility.

Emotional feelings are putatively ascribed to central representation of bodily states in the context of expectation and uncertainty in both internal state and external world. Neurodivergent people are more likely to experience co-occurring mental health challenges, although mechanistic insights underpinning this association are scarce. We therefore undertook a study to test whether imprecise processing of proprioceptive error signals may underlie the connection between neurodivergence and emotional dysregulation. In a cohort of people with complex chronic conditions, including chronic pain/fatigue, and complex trauma, and in a comparison group, we assessed presence of neurodivergence, variant connective tissue manifested through joint hypermobility, and emotional dysregulation. We present a data-informed conceptual model showing that variant connective tissue determines whether proprioceptive surprise is linked with emotional dysregulation in neurodivergent individuals. We suggest that future research in this area may have important clinical implications for the interaction of mental and physical wellbeing in neurodivergent people. This article is part of the theme issue 'Sensing and feeling: an integrative approach to sensory processing and emotional experience'.

Understanding the flexion-relaxation phenomenon in non-specific chronic low back pain patients throught immersive virtual reality feedback approach.

The flexion-relaxation phenomenon (FRP) is frequently absent among non-specific chronic low back pain (NSCLBP) patients. However, it is unknown whether this absence is intrinsic to their pathology or merely a consequence of reduced trunk flexion. Immersive virtual reality (IVR) can create a patient avatar whose range of motion can be modulated to differ from the real movement. The present study enrolled 15 NSCLBP patients and 15 asymptomatic participants with similar characteristics to disentangle the relationship between range of motion and the FRP in NSCLBP using IVR. Trunk kinematics and lumbar muscle electromyography were assessed. The IVR environment was combined with a motion capture system to create avatars that moved like each participant. The IVR display showed a closed room and a mirror reflecting the subject's avatar with a target line to be reached by trunk flexion. The avatar's trunk movements were modulated from reality, leading the participants to flex their trunk more than their voluntary maximum trunk flexion. Under IVR conditions, NSCLBP patients significantly increased their trunk flexion angle, which was coupled with a significant improvement in the FRP. The absence of the FRP among the NSCLBP population appeared to be primarily related to reduced trunk flexion.

Effect of exercise and manual therapy or kinesiotaping on sEMG and pain perception in chronic low back pain: a randomized trial.

The importance of incorporating lumbo-pelvic stability core and controlling motor exercises in patients with chronic low back pain (CLBP) reinforces the use of strategies to improve biopsychosocial beliefs by reducing biomedical postulations. However, clinical practice guidelines recommend multimodal approaches incorporating exercise and manual therapy (MT), and instead reject the application of kinesiotape (KT) in isolation. Therefore, the objectives of this study were to analyze the effects of 12 weeks of exercises combined with MT or KT on perceived low back pain using the visual analog scale (VAS) and muscle electric activity measured with electromyography (EMG) of the rectus abdominis and multifidus in CLBP (mild disability) and to explore the relationship between the rectus abdominis and multifidus ratios and pain perception after intervention. A blinded, 12-week randomized controlled trial (RCT) was carried out, involving three parallel groups of patients with CLBP. The study was registered at Clinicaltrial.gov and assigned the identification number NCT05544890 (19/09/22). The trial underwent an intention-to-treat analysis. The primary outcome revealed a multimodal treatment program supplemented by additional therapies such as MT and KT, resulting in significant reductions in perceived low back pain. The subjective assessment of individuals with CLBP indicated no discernible distinction between exclusive core stability exercises and control-motor training when combined with MT or KT. Notably, our findings demonstrated positive alterations in both the mean and peak EMG values of the right rectus abdominis in the exercise group, suggesting a beneficial impact on muscle activation. This study focused on assessing the activation levels of the trunk musculature, specifically the rectus abdominis (RA) and multifidus (MF), in individuals with CLBP exhibiting mild disability according to the Oswestry Disability Index. Importantly, improvements in the VAS values were observed independently of changes in muscle electrical activity.

Effects of Wrist Stability Training Combined with Grip Strength Exercise on Pain and Function in Patients with Nonspecific Chronic Wrist Pain.

Background and Objectives: Non-specific chronic wrist pain is wrist pain that occurs without a specific cause, such as trauma, and may limit the range of motion of the joints of the wrist and hand, affecting muscle strength, grip strength, and function. This study aimed to determine the effects of grip-strengthening exercises combined with wrist stability training on pain and function in patients with non-specific chronic wrist pain. Materials and Methods: The subjects of the study were 31 patients with wrist pain. To determine the effect of grip-strengthening exercises combined with wrist stability training, 15 participants participated in grip-strengthening exercises combined with wrist stability training and 16 control subjects participated. The experimental group participated in wrist-stability training. Grip-strengthening exercises combined with wrist stability training were performed for 20 min/day twice a week for 4 weeks, and relaxation massage and conservative physical therapy were performed for 20 min/day twice a week for 4 weeks. The control group received relaxation massage and conservative physical therapy for 40 min/day twice a week for 4 weeks. A visual pain scale was used to evaluate the degree of pain before and after treatment, and a patient-rated wrist evaluation was used to evaluate wrist function. Results: The results showed that the visual score significantly decreased in the time effect before and after the intervention in both groups (p < 0.001), patient-rated wrist evaluation significantly decreased (p < 0.001), and grip strength and muscle strength significantly increased (p < 0.001). The results of this study showed that grip-strengthening exercises combined with wrist stability training were effective in improving pain, function, grip strength, and muscle strength in patients with non-specific chronic wrist pain. Conclusions: Grip-strengthening exercises combined with wrist stability training can be used as an effective intervention method to improve pain, function, grip strength, and muscle strength, emphasizing the need for wrist exercise interventions in patients with non-specific chronic wrist pain in the future.

Musculoskeletal evaluation of the lower pelvic complex in women with endometriosis: A case-control study.

OBJECTIVE: Use clinical pain measurement tools to investigate and compare the prevalence of pelvic loin disoders in women with and without endometriosis. STUDY DESIGN: Chronic pelvic pain (CPP) associated with endometriosis has diverse origins, including musculoskeletal factors. Musculoskeletal dysfunction in the pelvic region is theorized to result from sustained muscular contraction, triggered by altered visceral stimuli and adoption of antalgic postures, causing secondary damage to muscles, ligaments, and joints. CPP significantly impacts quality of life, relationships, sexuality, and mental health. However, limited data exists on musculoskeletal impacts of endometriosis and CPP. It was made a case-control study at Maternidade Escola Assis Chateaubriand from August 2017 to January 2021. Evaluated 71 women: 41 in endometriosis group (EG) and 30 in control group (CG). Data collection included sociodemographic questionnaires, musculoskeletal physiotherapeutic evaluations, pain mapping, pressure pain thresholds, kinesiophobia, and disability measurements. Statistical analysis was performed using Spearman's Rho test to determine correlations. RESULTS: Mean age of participants was 31 years. EG exhibited lower pain threshold variations in lumbopelvic trigger points than CG (P < .05). Significant muscle flexibility differences between groups were observed; EG had reduced flexibility (P < .05). Most common pain areas were hypogastrium in EG (48.78 %) and left lumbar in CG (30 %). EG had higher kinesiophobia values (P = .009). There was a weak association between kinesiophobia-pressure threshold association observed in CG's lumbar pelvic region. CONCLUSION: Women with Endometriosis and CPP exhibit higher prevalence of musculoskeletal disorder, lower pain thresholds, decreased lumbopelvic muscle range of motion, higher kinesiophobia scores, and increased disability indices with low back pain compared to healthy women.

Brain activity changes after high/low frequency stimulation in a nonhuman primate model of central post-stroke pain.

Central post-stroke pain (CPSP) is a chronic pain resulting from a lesion in somatosensory pathways. Neuromodulation techniques, such as repetitive transcranial magnetic stimulation (rTMS) that target the primary motor cortex (M1), have shown promise for the treatment of CPSP. High-frequency (Hf) rTMS exhibits analgesic effects compared to low-frequency (Lf) rTMS; however, its analgesic mechanism is unknown. We aimed to elucidate the mechanism of rTMS-induced analgesia by evaluating alterations of tactile functional magnetic resonance imaging (fMRI) due to Hf- and Lf-rTMS in a CPSP monkey model. Consistent with the patient findings, the monkeys showed an increase in pain threshold after Hf-rTMS, which indicated an analgesic effect. However, no change after Lf-rTMS was observed. Compared to Lf-rTMS, Hf-rTMS produced enhanced tactile-evoked fMRI signals not only in M1 but also in somatosensory processing regions, such as the primary somatosensory and midcingulate cortices. However, the secondary somatosensory cortex (S2) was less active after Hf-rTMS than after Lf-rTMS, suggesting that activation of this region was involved in CPSP. Previous studies showed pharmacological inhibition of S2 reduces CPSP-related behaviors, and the present results emphasize the involvement of an S2 inhibitory system in rTMS-induced analgesia. Verification using the monkey model is important to elucidate the inhibition system.

Beyond pain: the influence of psychological factors on functional status in fibromyalgia.

OBJECTIVES: Fibromyalgia (FM) is characterised by chronic widespread pain, often associated with fatigue, sleep disturbance, cognitive and mood impairment. Pain is a complex and multidimensional experience that significantly impacts personal, social, and professional functioning. Psychological factors related to chronic pain include catastrophising and self-efficacy in managing the painful condition. Therefore, this study explores the influence of chronic pain and related psychological factors on functional outcomes in FM patients. METHODS: In this study, 91 Italian patients with FM were assessed using an online questionnaire. The questionnaire included instruments to assess pain, such as the Numerical Rating Scale (NRS) and the Brief Pain Inventory (BPI), psychological characteristics, such as the Pain Self-Efficacy Questionnaire (PSEQ) and the Pain Catastrophizing Scale (PCS), and health-related quality of life with the 12-item Short Form Survey (SF-12). Multiple regression models were run, using the Interference subscale of the BPI and the physical and mental components of the SF-12 as outcomes, and the NRS, PCS and PSEQ scales as predictors. RESULTS: Our analysis revealed that in our model, both PCS and PSEQ were significant predictors of BPI-Interference (PCS: ß=0.29; p=0.001; PSEQ: ß=-0.36; p<0.001); NRS and PSEQ significantly predicted SF-12-Physical score (NRS: ß=-0.32; p=<0.001; PSEQ: ß=.50; p<0.001); PCS was found to be the only significant predictor of SF-12-Mental scores (ß=-0.53; p<0.001). CONCLUSIONS: Our results suggested that psychological variables such as catastrophic thinking and self-efficacy play a significant role in determining daily functioning and physical and mental health status in FM patients, showing greater influence than pain intensity.

Multimodal therapeutic intervention program associated with photobiomodulation therapy for individuals with chronic nonspecific neck pain: protocol for a clinical trial.

BACKGROUND: Neck pain is a prevalent global musculoskeletal issue, significantly contributing to the loss of years of healthy life due to disability. Chronic nonspecific neck pain (CNNP) involves diverse symptoms impacting mobility and quality of life. While therapeutic exercises demonstrate efficacy, the role of photobiomodulation therapy (PBMT) remains uncertain. This study aims to assess the additional effects of PBMT within a multimodal therapeutic intervention for CNNP. METHODS: A randomized, two-arm, controlled, blind clinical trial follows CONSORT and SPIRIT guidelines. Participants diagnosed with CNNP will receive a stand-alone multimodal therapeutic intervention or the same program with additional PBMT. The primary outcomes will be assessed by the functional disability identified through applying the NDI (Neck Disability Index). Secondary outcomes will be pain intensity during rest and active neck movement, catastrophizing and kinesiophobia, functionality, and disability assessed at baseline, after 8 weeks, and at a 4-week follow-up. Both groups receive pain education before personalized interventions, including resistance exercises, neuromuscular activities, mobility, and body balance. The PBMT group undergoes low-level light therapy. Intention-to-treat analysis, using linear mixed models, employs data presented as mean, standard deviation, and differences with a 95% confidence interval. Non-normally distributed variables transform. Statistical significance is set at 5%. DISCUSSION: This study addresses a critical gap in understanding the combined effects of PBMT and therapeutic exercises for CNNP. The findings aim to guide clinicians, researchers, and CNNP sufferers through rigorous methodology and diverse outcome assessments, offering valuable insights into evidence-based practices for CNNP management. Data confidentiality is maintained throughout, ensuring participant privacy during statistical analysis. TRIAL REGISTRATION: Effects of adding photobiomodulation to a specific therapeutic exercise program for the treatment of individuals with chronic nonspecific neck pain, registration number: NCT05400473, on 2022-05-27.

Chronic Pain and Joint Hypermobility: A Brief Diagnostic Review for Clinicians and the Potential Application of Infrared Thermography in Screening Hypermobile Inflamed Joints.

Joint hypermobility syndromes, particularly chronic pain associated with this condition, including Hypermobile Ehlers-Danlos Syndrome (hEDS) and Hypermobility Spectrum Disorders (HSD), present diagnostic challenges due to their multifactorial origins and remain poorly understood from biomechanical and genomic-molecular perspectives. Recent diagnostic guidelines have differentiated hEDS, HSD, and benign joint hypermobility, providing a more objective diagnostic framework. However, incorrect diagnoses and underdiagnoses persist, leading to prolonged journeys for affected individuals. Musculoskeletal manifestations, chronic pain, dysautonomia, and gastrointestinal symptoms illustrate the multifactorial impact of these conditions, affecting both the physical and emotional well-being of affected individuals. Infrared thermography (IRT) emerges as a promising tool for joint assessment, especially in detecting inflammatory processes. Thermal distribution patterns offer valuable insights into joint dysfunctions, although the direct correlation between pain and inflammation remains challenging. The prevalence of neuropathies among hypermobile individuals accentuates the discordance between pain perception and thermographic findings, further complicating diagnosis and management. Despite its potential, the clinical integration of IRT faces challenges, with conflicting evidence hindering its adoption. However, studies demonstrate objective temperature disparities between healthy and diseased joints, especially under dynamic thermography, suggesting its potential utility in clinical practice. Future research focused on refining diagnostic criteria and elucidating the underlying mechanisms of hypermobility syndromes will be essential to improve diagnostic accuracy and enhance patient care in this complex and multidimensional context.

Using Resistance-Band Tests to Evaluate Trunk Muscle Strength in Chronic Low Back Pain: A Test-Retest Reliability Study.

Exercise is a front-line intervention to increase functional capacity and reduce pain and disability in people with low strength levels or disorders. However, there is a lack of validated field-based tests to check the initial status and, more importantly, to control the process and make tailored adjustments in load, intensity, and recovery. We aimed to determine the test-retest reliability of a submaximal, resistance-band test to evaluate the strength of the trunk stability muscles using a portable force sensor in middle-aged adults (48 ± 13 years) with medically diagnosed chronic low back pain and healthy peers (n = 35). Participants completed two submaximal progressive tests of two resistance-band exercises (unilateral row and Pallof press), consisting of 5 s maintained contraction, progressively increasing the load. The test stopped when deviation from the initial position by compensation movements occurred. Trunk muscle strength (CORE muscles) was monitored in real time using a portable force sensor (strain gauge). Results revealed that both tests were highly reliable (intra-class correlation [ICC] > 0.901) and presented low errors and coefficients of variation (CV) in both groups. In particular, people with low back pain had errors of 14-19 N (CV = 9-12%) in the unilateral row test and 13-19 N (CV = 8-12%) in the Pallof press. No discomfort or pain was reported during or after the tests. These two easy-to-use and technology-based tests result in a reliable and objective screening tool to evaluate the strength and trunk stability in middle-aged adults with chronic low back pain, considering an error of measurement < 20 N. This contribution may have an impact on improving the individualization and control of rehabilitation or physical training in people with lumbar injuries or disorders.

Mendelian randomization highlights sleep disturbances mediated the effect of depression on chronic pain.

INTRODUCTION: Depression and chronic pain are significant contributors to the global burden of disease. Previous research has revealed complex relationships between these two conditions, which may be influenced by sleep quality. However, observational studies have limitations, including confounding factors and reverse causation. This study aims to explore the mediating effects of sleep on the relationship between depression and chronic pain using Mendelian randomization (MR). METHODS: We conducted a two-step, two-sample MR study using mediation analysis. We obtained major depressive disorder (MDD) Genome-Wide Association Studdies (GWAS) data from Wray et al.'s GWAS meta-analysis. Phenotypic data related to sleep were collected from the UK Biobank. Chronic pain data were obtained from the Finnish database. RESULTS: MR analysis revealed significant genetic associations between MDD and chronic localized pain [IVW: odds ratio (OR) = 1.26, 95% confidence interval (CI) = 1.16-1.38, p = 2.52 × 10-7] as well as fibromyalgia (IVW: OR = 2.17, 95% CI = 1.34-3.52, p = .002). Genetic susceptibility for MDD was also associated with insomnia (IVW: OR = 1.10, 95% CI = 1.06-1.13, p = 3.57 × 10-8) and self-reported short sleep duration (IVW: OR = 1.03, 95% CI = 1.00-1.06, p = .047). The mediating effects of insomnia and fibromyalgia on the pathway from depression to chronic regional pain were 1.04 and 1.03, respectively, with mediation proportions of 12.8% and 15.2%. Insomnia mediated the pathway between depression and fibromyalgia with an effect of 1.12, accounting for 15.2% of the total effect. CONCLUSION: This two-step MR analysis strengthens the evidence of genetic predictive associations between depression and chronic pain, highlighting the mediating roles of insomnia and short sleep duration. It further elucidates the specific roles of distinct sleep disorders, differentiating insomnia and short sleep duration from other sleep-related phenotypes.

Effects of cervicothoracic mobility programme on pain, range of motion and function in patients with chronic back pain.

Objective: To determine the effects of the cervicothoracic mobility programme on pain, range of motion and function in patients with chronic back pain. METHODS: The randomised controlled trial was conducted from April to November 2022 at the Physiotherapy Department of Syed Medical Complex, Sialkot, Pakistan, and comprised patients of either gender aged 18-50 years who had a minimum of 6 months of chronic back pain with moderate disability. They were randomly allocated to experimental group A and control group B. Group A subjects received cervical and thoracic mobilisation with conventional physical therapy, while group B subjects received conventional physical therapy alone. The treatment duration was 45 minutes per session, with 3 sessions per week for 3 weeks. Numeric Pain Rating Scale, Oswestry Disability Index and a goniometer was used to assess pain, disability and for the range of motion. Data was analysed using SPSS 25. RESULTS: Of the 44 patients, 22(50%) were in each of the 2 groups. Group A had 14(63.6%) females and 8(36.4%) males with overall mean age 36.45±10.80 years, while group B had 16(72.7%) females and 6(27.3%) males with overall mean age 35.77±11.05 years. There was a significant inter-group difference in terms of pain, function and flexion (p<0.05), while the difference was not significant in terms of extension, right and left lateral rotation (p>0.05). Intragroup analysis showed significant improvement in both groups (p<0.05). Conclusion: Cervicothoracic mobilisation was more effective in improving pain, functionality and range of motion in patients with chronic low back pain. ClinicalTrial gov Identifier: NCT05347251.

Targeted vibratory therapy as a treatment for proprioceptive dysfunction: Clinical trial in older patients with chronic low back pain.

INTRODUCTION: Proprioceptive function declines with age, leading to falls, pain, and difficulties in performing activities of daily living among older adults. Although individuals with low back pain (LBP) exhibit decreased lumbosacral proprioception in various postures, the mechanism by which reduced proprioceptive function causes LBP remains uncertain. Vibratory stimulation may enhance proprioceptive function; however, its efficacy in treating LBP has not been investigated. Thus, we investigated the feasibility of improving proprioceptive function and its effect on alleviating chronic LBP in older patients through targeted vibratory therapy (TVT) administration. METHODS: This single arm designed trial included older patients aged >65 years with non-specific chronic LBP. TVT involved applying vibratory stimulation, matching the frequency of dysfunctional receptors, for 1 min daily over 14 days to activate proprioceptors; patients performed TVT three times daily at home. In cases of reduced proprioceptive function at multiple sites, TVT was aimed at the lowest frequency band value. LBP and proprioceptive function were evaluated at 2 weeks after TVT and at 2 weeks after the end of TVT in patients with declined proprioception in the trunk or lower extremities. RESULTS: Overall, 56 patients with chronic LBP were enrolled; 32 patients were recruited for treatment based on a proprioceptive dysfunction diagnosis and 24 patients were recruited with a normal diagnosis with no significant differences observed between the two sets of patients in sarcopenia-related factors and clinical proprioception-related characteristics. No patient had any adverse events. Two weeks after TVT, the numerical pain rating scale score improved to <3 points in 78.1% of patients, with 73.1% of patients achieving a score of ≤ 3 points. Proprioceptive function improved in 81.3% of cases, and engagement in activities of daily living improved significantly. CONCLUSIONS: TVT demonstrated efficacy in improving proprioception and alleviating LBP in older patients with impaired proprioceptive function without affecting non-targeted proprioceptors.

Neck Kinematics in Patients With Chronic Mechanical Neck Pain: An Observational Study to Explore the Integration of Multiple Influencing Factors Through a Bayesian Model-Based Approach.

The aim of this observational, cross-sectional study is to evaluate potential differences in kinematics, specifically range of motion (ROM) and velocity, during planar cervical movements between patients with non-traumatic chronic neck pain and disability and asymptomatic controls, while accounting for potential influencing variables of age, sex and fear of movement. The influence of pain intensity, neck disability, age, sex or fear of motion on kinematics was analyzed through robust multivariate Bayesian regression models fitted using the brms library in R. Forty-three patients with neck pain (aged 36.70 ± 13.75 years; 10 men and 33 women) and 42 asymptomatic participants (aged 32.74 ± 13.24 years; 25 men and 17 women) completed the study protocol. The presence of neck pain/disability was associated with lower ROM and peak velocity during all planar movements when considering the influence of age, sex or fear of motion, with standardized regression coefficients that had a small effect size (ranged from 0.11 to 0.28) and estimated differences of less than 2.21° in ROM and 25.61°/s in peak velocity. Although patients with chronic mechanical neck pain showed reduced ROM and peak velocity, the small effect sizes and the low estimated differences between groups question the relevance and clinical usefulness of kinematic analysis of planar movements in samples of patients similar to those included in our study. It is probable that there are differences between the groups, but it is insufficient to rely solely on kinematic variables for patient discrimination. This limitation likely arises from the substantial variability in patient kinematics.

Emotional contagion and cognitive empathy regulate the effect of depressive symptoms on empathy-related brain functional connectivity in patients with chronic back pain.

BACKGROUND: Chronic pain and depression share common neural mechanisms, but their impacts on empathy are different. It is unclear how comorbid depressive symptoms affect empathy-related brain function in patients with chronic pain. METHODS: A total of 29 healthy participants and 107 patients with chronic back pain (CBP) were included in this study. All subjects underwent a functional MRI scan with concurrent empathic stimulation. Multiple linear regression, moderation analysis, and mediation analysis were used to explore the impacts of chronic pain and comorbid depression on empathy. RESULTS: The interaction between the pain intensity and the depressive symptoms affected the functional connectivity (FC) of the insula-middle frontal gyrus (MFG), and the severity of the self-rating depression scale (SDS) scores moderated the effect of the pain on the left insula-left MFG FC. Within the CBP group, the emotional contagion (EC) scores served as a mediator in the association between the SDS scores and the FC of the left middle cingulate cortex (MCC)-inferior temporal gyrus (ITG), and the level of cognitive empathy (CE) moderated the effect of the SDS scores on the left MCC-ITG FC. LIMITATIONS: There is a lack of research on the effects of depressive symptoms on empathy in individuals with different types of chronic pain. CONCLUSION: Depressive symptoms were strongly associated with the emotional contagion in patients with chronic back pain. Furthermore, the emotional contagion and the cognitive empathy regulated the effect of the comorbid depressive symptoms on the MCC-ITG connectivity in patients with chronic back pain.