RESUMEN
OBJECTIVES: A high incidence of attention-deficit hyperactivity disorder (ADHD) has been reported in chronic pain (ChP) patients. Furthermore, an association between ChP and muscular dysregulation has been reported in adults with ADHD. The present study investigated whether ADHD was more prevalent among psychiatric outpatients with ChP than those without ChP, and if there was an association between ChP, muscular dysregulation and characteristics of pain in patients with ADHD. METHODS: One-hundred and twenty-one individuals remitted to an outpatient psychiatry unit took part in this naturalistic epidemiological cross-sectional study. They were assessed with a pain self-report form (localization, intensity, and onset) and a test of muscle dysregulation (the Motor Function Neurological Assessment). Prevalence of ADHD among patients with ChP, as well as the qualitative characteristics of ChP within the ADHDgroup are reported. Both ChP and pain intensity correlated with muscular dysregulation through Spearman's rho analysis. Additionally, the relationship between various diagnostic categories (ADHD, affective disorders, anxiety, or personality disorders) and incidence of axial pain was evaluated in logistic regression. RESULTS: ADHD was significantly more prevalent in patients with ChP, than in patients without ChP. In the ADHD group, ChP and pain intensity was associated with muscular dysregulation, particularly with high muscle tone. ChP was more axial and widespread, than for the patients without ADHD, and started at an early age. ADHD diagnosis predicted axial pain, whereas affective-, anxiety-, or personality disorders did not. CONCLUSIONS: The study suggests that ChP in ADHD is associated with muscular dysregulation and is qualitatively different from ChP in psychiatric patients without ADHD. These findings may lead to further understanding of potential mechanisms involved in ADHD and ChP, and in turn to new treatment strategies for both disorders.
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Trastorno por Déficit de Atención con Hiperactividad , Dolor Crónico , Humanos , Trastorno por Déficit de Atención con Hiperactividad/fisiopatología , Trastorno por Déficit de Atención con Hiperactividad/epidemiología , Dolor Crónico/fisiopatología , Dolor Crónico/epidemiología , Masculino , Femenino , Estudios Transversales , Adulto , Persona de Mediana Edad , Prevalencia , Dimensión del Dolor , Adulto JovenRESUMEN
Studies reported the existence of instability catch (IC) during trunk flexion in patients with chronic low back pain (CLBP). However, different movement speeds can cause different neuromuscular demands resulting in altered kinematic patterns. In addition, kinematic characterization corresponding to clinical observation of IC is still limited. Therefore, this study aimed to determine (1) the association between movement speed and kinematic parameters representing IC during trunk flexion and (2) the differences in kinematic parameters between individuals with and without CLBP. Fifteen no low back pain (NoLBP) and 15 CLBP individuals were recruited. Inertial measurement units (IMU) were attached to T3, L1, and S2 spinous processes. Participants performed active trunk flexion while IMU data were simultaneously collected. Total trunk, lumbar, and pelvic mean angular velocity (T_MV, L_MV, and P_MV), as well as number of zero-crossings, peak-to-peak, and area of sudden deceleration and acceleration (Num, P2P, and Area), were derived. Pearson's correlation tests were used to determine the association between T_MV and L_MV, P_MV, Num, P2P, and Area. An ANCOVA was performed to determine the difference in kinematic parameters between groups using movement speed as a covariate. Significant associations (P < 0.05) were found between movement speed and other kinematic parameters, except for Area. Results showed that L_MV significantly differed from the P_MV (P = 0.002) in the CLBP group, while a significant between-group difference (P = 0.037) was found in the P_MV. Additionally, significant between-group differences (P < 0.05) in P2P and Area were observed. The associations between movement speed and kinematic parameters suggest that movement speed changes can alter kinematic patterns. Therefore, clinicians may challenge lumbopelvic neuromuscular control by modifying movement speed to elicit greater change in kinematic patterns. In addition, the NoLBP group used shared lumbar and pelvic contributions, while the CLBP group used less pelvic contribution. Finally, P2P and Area appeared to offer the greatest sensitivity to differentiate between the groups. Overall, these findings may enhance the understanding of the mechanism underlying IC in CLBP.
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Dolor de la Región Lumbar , Movimiento , Humanos , Dolor de la Región Lumbar/fisiopatología , Fenómenos Biomecánicos , Masculino , Femenino , Adulto , Movimiento/fisiología , Adulto Joven , Dolor Crónico/fisiopatología , Rango del Movimiento Articular/fisiologíaRESUMEN
BACKGROUND: This study is a randomized controlled, biopsychosocial study investigating the effectiveness of pain neuroscience education (PNE) and motor imagery-based exercise protocol (MIEP) on fibromyalgia pain. METHODS: Our study has four groups (MIEP n = 12, PNE n = 12, MIEP + PNE n = 14, Control n = 12) and all participants (n = 50) consist of patients diagnosed with fibromyalgia with chronic back pain. The primary outcome measure was pain intensity, and secondary outcome measures were beliefs, kinesiophobia, anxiety-depression, cognitive-mood, self-esteem, and body awareness. RESULTS: A statistically significant decrease in pain intensity was observed in all experimental groups, without any group being superior (Visual Analog Scale [VAS]: MIEP + PNE p = .003, 95% confidence interval [CI], -4.7078 to -0.9922; MIEP p = .003, 95% CI, -5.4806 to -1.0194; PNE p = .002, 95% CI, -3.6139 to -1.5461). There was a significant improvement in organic beliefs in both groups where PNE was applied (MIEP + PNE: p = .017, 95% CI, -7.8211 to -0.3189; PNE: p = .003, 95% CI, -9.7999 to -0.0401). A significant superiority in organic pain beliefs was detected in the MIEP + PNE group compared to the control group (p = .008, 95% CI, 1.7241-9.4959). CONCLUSIONS: According to this study, in which MIEP and PNE were combined, there was a decrease in pain intensity when both applications were applied together and when they were applied one by one. MIEP has improved her motor imagery ability, improved pain and increased body awareness. PNE has improved people's organic pain beliefs; removed people from fears, catastrophizing, and negative thoughts about pain; improved easier management of psychological processes and cognitive-emotion regulation ability.
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Terapia por Ejercicio , Fibromialgia , Imágenes en Psicoterapia , Humanos , Fibromialgia/terapia , Fibromialgia/rehabilitación , Fibromialgia/psicología , Fibromialgia/fisiopatología , Femenino , Imágenes en Psicoterapia/métodos , Persona de Mediana Edad , Adulto , Terapia por Ejercicio/métodos , Masculino , Educación del Paciente como Asunto/métodos , Neurociencias , Manejo del Dolor/métodos , Dolor Crónico/terapia , Dolor Crónico/rehabilitación , Dolor Crónico/fisiopatología , Dimensión del Dolor , Ansiedad/terapia , AutoimagenRESUMEN
The absence of a comprehensive understanding of the neural basis of spontaneous pain limits the development of therapeutic strategies targeting this primary complaint of patients with chronic pain. Here we report a distinct neuronal ensemble within the prelimbic cortex which processes signals related to spontaneous pain in rats with chronic inflammatory pain. This neuronal ensemble specifically encodes spontaneous pain-related behaviors, independently of other locomotive and evoked behaviors. Activation of this neuronal ensemble elicits marked spontaneous pain-like behaviors and enhances nociceptive responses, whereas prolonged silencing of its activities alleviates spontaneous pain and promotes overall recovery from inflammatory pain. Notably, afferents from the primary somatosensory cortex and infralimbic cortex bidirectionally modulate the activities of the spontaneous pain-responsive prelimbic cortex neuronal ensemble and pain behaviors. These findings reveal the cortical basis of spontaneous pain at the neuronal level, highlighting a distinct neuronal ensemble within the prelimbic cortex and its associated pain-regulatory brain networks.
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Inflamación , Neuronas , Ratas Sprague-Dawley , Corteza Somatosensorial , Animales , Neuronas/metabolismo , Neuronas/fisiología , Masculino , Ratas , Corteza Somatosensorial/fisiopatología , Dolor/fisiopatología , Conducta Animal , Modelos Animales de Enfermedad , Dolor Crónico/fisiopatología , Corteza Prefrontal/fisiopatologíaRESUMEN
Trunk control involves integration of sensorimotor information in the brain. Individuals with chronic low back pain (cLBP) have impaired trunk control and show differences in brain structure and function in sensorimotor areas compared with healthy controls (HC). However, the relationship between brain structure and trunk control in this group is not well understood. This cross-sectional study aimed to compare seated trunk control and sensorimotor white matter (WM) structure in people with cLBP and HC and explore relationships between WM properties and trunk control in each group. Thirty-two people with cLBP and 35 HC were tested sitting on an unstable chair to isolate trunk control; performance was measured using the 95% confidence ellipse area (CEA95) of center-of-pressure tracing. A WM network between cortical sensorimotor regions of interest was derived using probabilistic tractography. WM microstructure and anatomical connectivity between cortical sensorimotor regions were assessed. A mixed-model ANOVA showed that people with cLBP had worse trunk control than HC (F = 12.96; p < .001; ηp2 = .091). There were no differences in WM microstructure or anatomical connectivity between groups (p = 0.564 to 0.940). In the cLBP group, WM microstructure was moderately correlated (|r| = .456 to .565; p ≤ .009) with trunk control. Additionally, the cLBP group demonstrated stronger relationships between anatomical connectivity and trunk control (|r| = .377 to .618 p < .034) compared to the HC group. Unique to the cLBP group, WM connectivity between right somatosensory and left motor areas highlights the importance of interhemispheric information exchange for trunk control. Parietal areas associated with attention and spatial reference frames were also relevant to trunk control. These findings suggest that people with cLBP adopt a more cortically driven sensorimotor integration strategy for trunk control. Future research should replicate these findings and identify interventions to effectively modulate this strategy.
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Dolor de la Región Lumbar , Corteza Sensoriomotora , Sustancia Blanca , Humanos , Dolor de la Región Lumbar/fisiopatología , Sustancia Blanca/diagnóstico por imagen , Sustancia Blanca/fisiopatología , Sustancia Blanca/patología , Masculino , Femenino , Adulto , Corteza Sensoriomotora/fisiopatología , Corteza Sensoriomotora/diagnóstico por imagen , Estudios Transversales , Persona de Mediana Edad , Torso/fisiopatología , Dolor Crónico/fisiopatología , Dolor Crónico/diagnóstico por imagen , Dolor Crónico/patología , Sedestación , Estudios de Casos y Controles , Imagen por Resonancia MagnéticaRESUMEN
Increasing evidence is present to enable pain measurement by using frontal channel EEG-based signals with spectral analysis and phase-amplitude coupling. To identify frontal channel EEG-based biomarkers for quantifying pain severity, we investigated band-power features to more complex features and employed various machine learning algorithms to assess the viability of these features. We utilized a public EEG dataset obtained from 36 patients with chronic pain during an eyes-open resting state and performed correlation analysis between clinically labelled pain scores and EEG features from Fp1 and Fp2 channels (EEG band-powers, phase-amplitude couplings (PAC), and its asymmetry features). We also conducted regression analysis with various machine learning models to predict patients' pain intensity. All the possible feature sets combined with five machine learning models (Linear Regression, random forest and support vector regression with linear, non-linear and polynomial kernels) were intensively checked, and regression performances were measured by adjusted R-squared value. We found significant correlations between beta power asymmetry (r = -0.375), gamma power asymmetry (r = -0.433) and low beta to low gamma coupling (r = -0.397) with pain scores while band power features did not show meaningful results. In the regression analysis, Support Vector Regression with a polynomial kernel showed the best performance (R squared value = 0.655), enabling the regression of pain intensity within a clinically usable error range. We identified the four most selected features (gamma power asymmetry, PAC asymmetry of theta to low gamma, low beta to low/high gamma). This study addressed the importance of complex features such as asymmetry and phase-amplitude coupling in pain research and demonstrated the feasibility of objectively observing pain intensity using the frontal channel-based EEG, that are clinically crucial for early intervention.
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Biomarcadores , Dolor Crónico , Electroencefalografía , Neuralgia , Humanos , Electroencefalografía/métodos , Masculino , Femenino , Persona de Mediana Edad , Dolor Crónico/fisiopatología , Dolor Crónico/diagnóstico , Neuralgia/fisiopatología , Neuralgia/diagnóstico , Adulto , Aprendizaje Automático , Anciano , Dimensión del Dolor/métodos , Descanso/fisiologíaRESUMEN
Assessing physical activity is important in the treatment of chronic conditions, including chronic low back pain (cLBP). ActiGraph™, a widely used physical activity monitor, collects raw acceleration data, and processes these data through proprietary algorithms to produce physical activity measures. The purpose of this study was to replicate ActiGraph™ algorithms in MATLAB and test the validity of this method with both healthy controls and participants with cLBP. MATLAB code was developed to replicate ActiGraph™'s activity counts and step counts algorithms, to sum the activity counts into counts per minute (CPM), and categorize each minute into activity intensity cut points. A free-living validation was performed where 24 individuals, 12 cLBP and 12 healthy, wore an ActiGraph™ GT9X on their non-dominant hip for up to seven days. The raw acceleration data were processed in both ActiLife™ (v6), ActiGraph™'s data analysis software platform, and through MATLAB (2022a). Percent errors between methods for all 24 participants, as well as separated by cLBP and healthy, were all less than 2%. ActiGraph™ algorithms were replicated and validated for both populations, based on minimal error differences between ActiLife™ and MATLAB, allowing researchers to analyze data from any accelerometer in a manner comparable to ActiLife™.
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Algoritmos , Ejercicio Físico , Dolor de la Región Lumbar , Humanos , Dolor de la Región Lumbar/fisiopatología , Dolor de la Región Lumbar/diagnóstico , Ejercicio Físico/fisiología , Masculino , Femenino , Adulto , Persona de Mediana Edad , Actigrafía/métodos , Actigrafía/instrumentación , Acelerometría/métodos , Acelerometría/instrumentación , Dolor Crónico/fisiopatología , Dolor Crónico/diagnóstico , Estudios de Casos y ControlesRESUMEN
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.
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Analgésicos Opioides , Comportamiento de Búsqueda de Drogas , Neuralgia , Neuronas , Oxicodona , Corteza Prefrontal , Animales , Oxicodona/farmacología , Corteza Prefrontal/efectos de los fármacos , Corteza Prefrontal/fisiopatología , Comportamiento de Búsqueda de Drogas/efectos de los fármacos , Ratones , Neuralgia/fisiopatología , Neuronas/efectos de los fármacos , Masculino , Femenino , Analgésicos Opioides/farmacología , Autoadministración , Dolor Crónico/fisiopatología , Factores SexualesRESUMEN
BACKGROUND: Motor control exercise is commonly applied in people with chronic low back pain (CLBP), but possibly not all people with CLBP have motor control impairments. We suggest movement precision as measure to identify motor control impairments. Movement precision has been operationalized as trunk movement variability (TMV) and as trunk tracking error(s) (TTE). OBJECTIVES: To compare the known-group validity and the responsiveness of TMV and TTE. DESIGN: We used a case-control comparison (Healthy controls (n = 30) vs CLBP (n = 60)) to assess the known-group validity. A cohort study, (measurements in week 3 and week 12 of treatment), was used to assess responsiveness. METHODS: TMV (temporal (CyclSD) and spatial (MeanSD)) was analyzed during standing, repetitive flexion and rotation tasks (35x). TTE was measured during movement target tracking tasks, again in flexion and rotation. Participants with CLBP followed a multidisciplinary intervention and both measures were assessed in week 3 and week 12 of treatment. 2-way MANOVA and 2-way ANOVA were used to assess the effect of Group (CLBP vs healthy controls) and direction (flexion vs rotation) on TMV and TTE. For responsiveness, 2-way MANOVA and 2-way ANOVA were used to assess the effect of treatment and direction on both measures. FINDINGS: At baseline, TMV was not different between groups, while TTE was higher in the people with CLBP (p = 0.005, np2 = 0.09). Treatment strongly decreased temporal TMV (p = 0.025, np2 = 0.33) and TTE (p < 0.001, np2 = 0.844). CONCLUSIONS: These results demonstrate that TTE is more sensitive to CLBP and more responsive to treatment than TMV.
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Dolor de la Región Lumbar , Movimiento , Torso , Humanos , Dolor de la Región Lumbar/terapia , Dolor de la Región Lumbar/fisiopatología , Masculino , Femenino , Estudios de Casos y Controles , Adulto , Persona de Mediana Edad , Movimiento/fisiología , Torso/fisiopatología , Estudios de Cohortes , Dolor Crónico/terapia , Dolor Crónico/fisiopatología , Rango del Movimiento Articular/fisiología , Terapia por Ejercicio/métodosRESUMEN
Chronic neuropathic pain and chronic tinnitus have been likened to phantom percepts, in which a complete or partial sensory deafferentation results in a filling in of the missing information derived from memory. 150 participants, 50 with tinnitus, 50 with chronic pain and 50 healthy controls underwent a resting state EEG. Source localized current density is recorded from all the sensory cortices (olfactory, gustatory, somatosensory, auditory, vestibular, visual) as well as the parahippocampal area. Functional connectivity by means of lagged phase synchronization is also computed between these regions of interest. Pain and tinnitus are associated with gamma band activity, reflecting prediction errors, in all sensory cortices except the olfactory and gustatory cortex. Functional connectivity identifies theta frequency connectivity between each of the sensory cortices except the chemical senses to the parahippocampus, but not between the individual sensory cortices. When one sensory domain is deprived, the other senses may provide the parahippocampal 'contextual' area with the most likely sound or somatosensory sensation to fill in the gap, applying an abductive 'duck test' approach, i.e., based on stored multisensory congruence. This novel concept paves the way to develop novel treatments for pain and tinnitus, using multisensory (i.e. visual, vestibular, somatosensory, auditory) modulation with or without associated parahippocampal targeting.
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Electroencefalografía , Neuralgia , Acúfeno , Acúfeno/fisiopatología , Humanos , Neuralgia/fisiopatología , Femenino , Masculino , Persona de Mediana Edad , Electroencefalografía/métodos , Adulto , Encéfalo/fisiopatología , Anciano , Dolor Crónico/fisiopatologíaRESUMEN
BACKGROUND: Chronic low back pain (LBP) is a leading cause of disability, which is exacerbated in some by repeated lifting. Electromyography (EMG) assessments of isolated erector spinae (ES) regions during lifting identified conflicting results. Here, high-density EMG comprehensively assesses the lumbar and thoracolumbar ES activity in people with and without LBP performing a multiplanar lifting task. METHODS: Four high-density EMG grids (two bilaterally) and reflective markers were affixed over the ES and trunk to record muscle activity and trunk kinematics respectively. The task involved cyclical lifting of a 5 kg box for â¼7 min from a central shelf to five peripheral shelves, returning to the first between movements, while monitoring perceived exertion. RESULTS: Fourteen LBP (26.9 ± 11.1 years) and 15 control participants (32.1 ± 14.6 years) completed the study. LBP participants used a strategy characterised by less diffuse and more cranially-focussed ES activity (P < 0.05). LBP participants also exhibited less variation in ES activity distribution between sides during movements distal to the central shelf (P < 0.05). There were few consistent differences in kinematics, but LBP participants reported greater exertion (P < 0.05). CONCLUSION: In the presence of mild LBP, participants used a less variable motor strategy, with less diffuse and more cranially-focussed ES activity; this motor strategy occurred concomitantly with increased exertion while completing this dynamic task.
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Electromiografía , Elevación , Dolor de la Región Lumbar , Humanos , Dolor de la Región Lumbar/fisiopatología , Masculino , Femenino , Adulto , Electromiografía/métodos , Dolor Crónico/fisiopatología , Fenómenos Biomecánicos/fisiología , Músculos Paraespinales/fisiopatología , Músculos Paraespinales/fisiologíaRESUMEN
Neuropathic pain is a significant and persistent issue for individuals with spinal cord injuries (SCI), severely impacting their quality of life. While changes at the peripheral and spinal levels are known to contribute to SCI-related pain, whether and how supraspinal centers contribute to post SCI chronic neuropathic pain is poorly understood. Here, we first validated delayed development of chronic neuropathic pain in mice with moderate contusion SCI. To identify supraspinal regions involved in the pathology of neuropathic pain after SCI, we next performed an activity dependent genetic screening and identified multiple cortical and subcortical regions that were activated by innocuous tactile stimuli at a late stage following contusion SCI. Notably, chemogenetic inactivation of pain trapped neurons in the lateral thalamus alleviated neuropathic pain and reduced tactile stimuli evoked cortical overactivation. Retrograde tracing showed that contusion SCI led to enhanced corticothalamic axonal sprouting and over-activation of corticospinal neurons. Mechanistically, ablation or silencing of corticospinal neurons prevented the establishment or maintenance of chronic neuropathic pain following contusion SCI. These results highlighted a corticospinal-lateral thalamic feed-forward loop whose activation is required for the development and maintenance of chronic neuropathic pain after SCI. Our data thus shed lights into the central mechanisms underlying chronic neuropathic pain associated with SCI and the development of novel therapeutic avenues to treat refractory pain caused by traumatic brain or spinal cord injuries.
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Neuralgia , Tractos Piramidales , Traumatismos de la Médula Espinal , Animales , Neuralgia/etiología , Neuralgia/patología , Traumatismos de la Médula Espinal/complicaciones , Traumatismos de la Médula Espinal/patología , Traumatismos de la Médula Espinal/fisiopatología , Ratones , Tractos Piramidales/patología , Ratones Endogámicos C57BL , Dolor Crónico/etiología , Dolor Crónico/fisiopatología , Masculino , Neuronas/patología , Femenino , Ratones TransgénicosRESUMEN
BACKGROUND: Feline osteoarthritis (OA) leads to chronic pain and somatosensory sensitisation. In humans, sensory exposure can modulate chronic pain. Recently, electroencephalography (EEG) revealed a specific brain signature to human OA. However, EEG pain characterisation or its modulation does not exist in OA cats, and all EEG were conducted in sedated cats, using intradermal electrodes, which could alter sensory (pain) perception. NEW METHOD: Cats (n=11) affected by OA were assessed using ten gold-plated surface electrodes. Sensory stimuli were presented in random orders: response to mechanical temporal summation, grapefruit scent and mono-chromatic wavelengths (500â¯nm-blue, 525â¯nm-green and 627â¯nm-red light). The recorded EEG was processed to identify event-related potentials (ERP) and to perform spectral analysis (z-score). RESULTS: The procedure was well-tolerated. The ERPs were reported for both mechanical (F3, C3, Cz, P3, Pz) and olfactory stimuli (Cz, Pz). The main limitation was motion artifacts. Spectral analysis revealed a significant interaction between the power of EEG frequency bands and light wavelengths (p<0.001). All wavelengths considered, alpha band proportion was higher than that of delta and gamma bands (p<0.044), while the latter was lower than the beta band (p<0.016). Compared to green and red, exposure to blue light elicited distinct changes in EEG power over time (p<0.001). COMPARISON WITH EXISTING METHOD: This is the first demonstration of EEG feasibility in conscious cats with surface electrodes recording brain activity while exposing them to sensory stimulations. CONCLUSION: The identification of ERPs and spectral patterns opens new avenues for investigating feline chronic pain and its potential modulation through sensory interventions.
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Dolor Crónico , Electroencefalografía , Estudios de Factibilidad , Vigilia , Animales , Gatos , Electroencefalografía/métodos , Dolor Crónico/fisiopatología , Vigilia/fisiología , Masculino , Osteoartritis/fisiopatología , Potenciales Evocados/fisiología , Encéfalo/fisiopatología , Encéfalo/fisiología , Femenino , Estimulación Física , Modelos Animales de Enfermedad , Percepción del Dolor/fisiologíaRESUMEN
Despite the widespread research about the effects of attentional focus on balance control in different populations, to the best of our knowledge, no study has yet investigated the effects of attentional focus instructions on balance control in individuals with chronic low back pain (CLBP). Therefore, this study was aimed to compare the effects of internal focus (IF) and external focus (EF) of attention on quiet standing balance control between individuals with CLBP and healthy controls. Twenty individuals with CLBP and 20 healthy controls were enrolled in this quasi-experimental study. The participants were asked to stand still with eyes open and eyes closed while performing three tasks: baseline standing with no focus instructions, internally focusing on their feet, and externally focusing on two markers were placed on the force platform. Statistical analyses showed a significant main effect of group for mean total velocity (p = 0.02), area (p = 0.01), and displacement in mediolateral (ML) direction (p = 0.003). Moreover, a significant main effect of vision was observed for mean total velocity (p < 0.001), area (p < 0.001), and displacement in anteroposterior (AP) (p < 0.001) and ML directions (p < 0.001). Also, the results revealed a significant main effect of attentional focus for mean total velocity (p < 0.001), area (p < 0.001), and displacement in AP (p < 0.001) and ML directions (p = 0.01). Our results showed that in both healthy controls and individuals with CLBP, EF led to improve quiet standing balance control compared to IF and control conditions. From a clinical perspective, it may be useful for physical therapists to consider the use of instruction cues that direct performer's attention away from the body for improving quiet standing balance control in individuals with CLBP.
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Atención , Dolor de la Región Lumbar , Equilibrio Postural , Humanos , Equilibrio Postural/fisiología , Dolor de la Región Lumbar/fisiopatología , Masculino , Femenino , Adulto , Adulto Joven , Posición de Pie , Dolor Crónico/fisiopatología , Fenómenos BiomecánicosRESUMEN
OBJECTIVE: The present study aimed to investigate whether subjective and objective measures of pain habituation can be used as potential markers for central sensitization across various chronic pain patients. METHODS: Two blocks of contact-heat stimuli were applied to a non-painful area in 93 chronic pain patients (low back pain, neuropathic pain, and complex regional pain syndrome) and 60 healthy controls (HC). Habituation of pain ratings, contact-heat evoked potentials (CHEP), and sympathetic skin responses (SSR) was measured. RESULTS: There was no significant difference in any measure of pain habituation between patients and HC. Even patients with apparent clinical signs of central sensitization showed no reduced pain habituation. However, prolonged baseline CHEP and SSR latencies (stimulation block 1) were found in patients compared to HC (CHEP: Δ-latency = 23 ms, p = 0.012; SSR: Δ-latency = 100 ms, p = 0.022). CONCLUSION: Given the performed multimodal neurophysiological testing protocol, we provide evidence indicating that pain habituation may be preserved in patients with chronic pain and thereby be of limited use as a sensitive marker for central sensitization. These results are discussed within the framework of the complex interactions between pro- and antinociceptive mechanism as well as methodological issues. The prolonged latencies of CHEP and SSR after stimulation in non-painful areas may indicate subclinical changes in the integrity of thermo-nociceptive afferents, or a shift towards antinociceptive activity. This shift could potentially affect the relay of ascending signals. SIGNIFICANCE: Our findings challenge the prevailing views in the literature and may encourage further investigations into the peripheral and central components of pain habituation, using advanced multimodal neurophysiological techniques.
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Dolor Crónico , Habituación Psicofisiológica , Humanos , Masculino , Dolor Crónico/fisiopatología , Femenino , Habituación Psicofisiológica/fisiología , Persona de Mediana Edad , Adulto , Anciano , Dimensión del Dolor/métodos , Neuralgia/fisiopatología , Calor , Umbral del Dolor/fisiología , Sensibilización del Sistema Nervioso Central/fisiologíaRESUMEN
OBJECTIVES: People with low back pain (LBP) exhibit altered coordination, possibly indicating guarded movement. The connection between these changes and pain-related threat remains unclear. We aimed to determine if pain-related threat was related to spinal coordination and variability, during a lifting task, in people with chronic LBP. METHODS: Participants were adults with chronic LBP (n = 47). Upper lumbar, lower lumbar, and hipkinematics were measured during 10crate lifting/lowering repetitions. Coordination and variability of the Hip-Lower Lumbar, and Lower Lumbar-Upper Lumbar joint pairs were calculated. Pain-related threat was measured using the Tampa Scale for Kinesiophobia, the Pain Catastrophizing Scale, and task-specific fear. Linear regression analyses tested the relationship between pain-related threat and coordination. RESULTS: Adding catastrophizing to our base model (sex) explained variance in Hip-Lower lumbar coordination (r2 change = 0.125, p = 0.013). General and task specific measures of fear were unrelated to coordination and variability at both joint pairs (r2 change < 0.064, p > 0.05). Exploratory t-tests revealed subgroups aligned with phenotypes of "tight" and "loose" control, where "tight" control was characterized by greater catastrophizing and disability. CONCLUSION: Pain catastrophizing, but not measures of fear, was related to more in-phase ("tight") Hip-Lower Lumbar coordination during lifting/lowering. Considering this relationship based on subgroups may add clarity.
Asunto(s)
Catastrofización , Dolor Crónico , Miedo , Elevación , Dolor de la Región Lumbar , Humanos , Dolor de la Región Lumbar/fisiopatología , Dolor de la Región Lumbar/psicología , Masculino , Femenino , Estudios Transversales , Adulto , Catastrofización/psicología , Dolor Crónico/fisiopatología , Dolor Crónico/psicología , Persona de Mediana Edad , Dimensión del Dolor/métodosRESUMEN
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.
Asunto(s)
Artrometría Articular , Vértebras Cervicales , Dolor Crónico , Dolor de Cuello , Rango del Movimiento Articular , Humanos , Dolor de Cuello/fisiopatología , Dolor de Cuello/diagnóstico , Rango del Movimiento Articular/fisiología , Femenino , Reproducibilidad de los Resultados , Masculino , Dolor Crónico/fisiopatología , Dolor Crónico/diagnóstico , Artrometría Articular/métodos , Adulto , Persona de Mediana Edad , Vértebras Cervicales/fisiopatología , Dimensión del Dolor/métodos , Variaciones Dependientes del ObservadorRESUMEN
Pain perception is the consequence of a complex interplay between activation and inhibition. Noradrenergic pain modulation inhibits nociceptive transmission and pain perception. The main source of norepinephrine (NE) in the central nervous system is the Locus Coeruleus (LC), a small but complex cluster of cells in the pons. The aim of this study is to review the literature on the LC-NE inhibitory system, its influence on chronic pain pathways and its frequent comorbidities. The literature research showed that pain perception is the consequence of nociceptive and environmental processing and is modulated by the LC-NE system. If perpetuated in time, nociceptive inputs can generate neuroplastic changes in the central nervous system that reduce the inhibitory effects of the LC-NE complex and facilitate the development of chronic pain and frequent comorbidities, such as anxiety, depression or sleeping disturbances. The exact mechanisms involved in the LC functional shift remain unknown, but there is some evidence that they occur through plastic changes in the medial and lateral pathways and their brain projections. Additionally, there are other influencing factors, like developmental issues, neuroinflammatory glial changes, NE receptor affinity and changes in LC neuronal firing rates.
Asunto(s)
Dolor Crónico , Locus Coeruleus , Norepinefrina , Locus Coeruleus/metabolismo , Humanos , Dolor Crónico/fisiopatología , Dolor Crónico/metabolismo , Animales , Norepinefrina/metabolismo , Plasticidad Neuronal , Neuronas/metabolismo , Neuronas/fisiología , Percepción del Dolor/fisiologíaRESUMEN
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.
Asunto(s)
Dolor Crónico , Dimensión del Dolor , Padres , Medición de Resultados Informados por el Paciente , Apoderado , Autoinforme , Humanos , Femenino , Dolor Crónico/psicología , Dolor Crónico/fisiopatología , Masculino , Niño , Padres/psicología , Adolescente , Dimensión del Dolor/métodosRESUMEN
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.