Mediating role of physical activity in the relationship between exercise-induced muscle pain and symptom severity in women with fibromyalgia.

Background: Individuals with fibromyalgia (FM) exhibit generalized hyperalgesia to pain stimuli, and physical activity (PA) is critical to manage FM symptoms.

Purpose: This study examined the relationship between exercise-induced muscle pain, symptom severity, and PA in 28 women with FM.

Methods: Muscle pain rating (MPR) was assessed during 3 minutes of submaximal isometric handgrip exercise, whereas PA and symptom severity were evaluated via self-report questionnaires.

Preferred Communication Strategies Used by Physical Therapists in Chronic Pain Rehabilitation: A Qualitative Systematic Review and Meta-Synthesis.

Objective: Lack of clarity regarding effective communication behaviors in chronic pain management is a barrier for implementing psychologically informed physical therapy approaches that rely on competent communication by physical therapist providers. This study aimed to conduct a systematic review and meta-synthesis to inform the development of a conceptual framework for preferred communication behaviors in pain rehabilitation.

Methods: Ten databases in the health and communication sciences were systematically searched for qualitative and mixed-method studies of interpersonal communication between physical therapists and adults with chronic pain.

A randomized controlled trial of yoga vs nonaerobic exercise for veterans with PTSD: Understanding efficacy, mechanisms of change, and mode of delivery.

Background And Objectives: Posttraumatic stress disorder (PTSD) is a chronic, disabling, and prevalent mental health disorder among Veterans. Despite the availability of empirically supported psychotherapies, many Veterans remain symptomatic after treatment and/or prefer to seek complementary and integrative health approaches, including yoga, to manage PTSD. The randomized controlled trial (RCT) described herein will evaluate the efficacy of a manualized yoga program as compared to nonaerobic exercise in reducing PTSD severity among Veterans.

Determination of Pain Phenotypes in Knee Osteoarthritis Using Latent Profile Analysis.

Objective: To identify clinical phenotypes of knee osteoarthritis (OA) using measures from the following domains: 1) multimorbidity; 2) psychological distress; 3) pain sensitivity; and 4) knee impairment or pathology.

Design: Data were collected from 152 people with knee OA and from 31 pain-free individuals. In participants with knee OA, latent profile analysis (LPA) was applied to the following measures: normalized knee extensor strength, Functional Comorbidity Index (FCI), Pain Catastrophizing Scale (PCS), and local (knee) pressure pain threshold.

Greater Severity and Functional Impact of Post-traumatic Headache in Veterans With Comorbid Neck Pain Following Traumatic Brain Injury.

Background: Post-traumatic headache (PTH) is a commonly experienced symptom after mild traumatic brain injury (mTBI). Blast injury- or blunt injury-related mechanisms for mTBI in veterans can also affect musculoskeletal structures in the neck, resulting in comorbid neck pain (NP). However, it is unknown whether the presence of comorbid NP may be associated with a different pattern of headache symptoms, physical functioning, or emotional functioning compared to those without comorbid NP.

Hormonal and Neuromuscular Responses to Breastfeeding: A Pilot Study.

Objectives: Difficult breastfeeding in the first weeks after birth may result in muscle tension in infants and activation of the maternal hypothalamic-pituitary-adrenal (HPA) axis and sympathetic nervous system (SNS). Our primary objective was to examine the feasibility of collecting neuroendocrine markers of maternal HPA axis and SNS activation (salivary cortisol and α-amylase [sAA]) and electromyographic (EMG) markers of infant distress during feeding in the first 2 weeks after birth. We also examined the relationships of these indices to each other and to mother-infant interactive behaviors during feeding.

Adaptations in Evoked Pain Sensitivity and Conditioned Pain Modulation after Development of Chronic Neck Pain.

Numerous studies demonstrate elevated pain sensitivity and impaired conditioned pain modulation (CPM) in patients with chronic musculoskeletal pain compared to healthy individuals; however, the time course of changes in pain sensitivity and CPM after the development of a chronic pain condition is unclear. Secondary analysis of data from a prospective investigation examined changes in evoked pain sensitivity and CPM before and after development of chronic neck pain (CNP). 171 healthy office workers participated in a baseline assessment, followed by monthly online questionnaires to identify those who developed CNP over the subsequent year.

Short-duration therapeutic massage reduces postural upper trapezius muscle activity.

Massage therapy has historically been used as a therapeutic treatment to help reduce pain and promote relaxation. The aim of this study was to investigate the effect of therapeutic massage on the upper trapezius muscles, which are commonly associated with increased muscle tension. This was a randomized crossover study.

Psychosocial stress alters the strength of reticulospinal input to the human upper trapezius.

Unlabelled: Psychosocial stress has been shown to influence several aspects of human motor control associated with the fight-or-flight response, including augmentation of upper trapezius muscle activity. Given the established role of the reticular formation in arousal, this study investigated the contribution of reticulospinal activation to trapezius muscle activity during exposure to an acute psychosocial stressor. Twenty-five healthy adults were exposed to startling acoustic stimuli (SAS) while performing a motor task during periods of low and high psychosocial stress.

Upper trapezius muscle activity in healthy office workers: reliability and sensitivity of occupational exposure measures to differences in sex and hand dominance.

Patterns of cervical muscle activity may contribute to overuse injuries in office workers. The purpose of this investigation was to characterise patterns of upper trapezius muscle activity in pain-free office workers using traditional occupational exposure measures and a modified Active Amplitude Probability Distribution Function (APDF), which considers only periods of active muscle contraction. Bilateral trapezius muscle activity was recorded in 77 pain-free office workers for 1-2 full days in their natural work environment.

Evaluation of Novel EMG Biofeedback for Postural Correction During Computer Use.

Postural correction is an effective rehabilitation technique used to treat chronic neck and shoulder pain, and is aimed toward reducing the load on the surrounding muscles by adopting a neutral posture. The objective of this investigation was to evaluate the effectiveness of real-time high-density surface EMG (HDsEMG) biofeedback for postural correction during typing. Twenty healthy participants performed a typing task with two forms of postural feedback: (1) verbal postural coaching and (2) verbal postural coaching plus HDsEMG biofeedback.

Psychosocial, Physical, and Neurophysiological Risk Factors for Chronic Neck Pain: A Prospective Inception Cohort Study.

Unlabelled: The purpose of this investigation was to identify modifiable risk factors for the development of first-onset chronic neck pain among an inception cohort of healthy individuals working in a high-risk occupation. Candidate risk factors identified from previous studies were categorized into psychosocial, physical, and neurophysiological domains, which were assessed concurrently in a baseline evaluation of 171 office workers within the first 3 months of hire. Participants completed monthly online surveys over the subsequent year to identify the presence of chronic interfering neck pain, defined as a Neck Disability Index score ≥5 points for 3 or more months.

Cardiovascular responses to an acute psychological stressor are associated with the cortisol awakening response in individuals with chronic neck pain.

Introduction: Dysregulation of the hypothalamic-pituitary-adrenal axis (HPA-axis) is common in individuals who experience chronic psychological stress, as well as individuals with chronic pain. Changes in cortisol availability in the presence of a chronic stressor such as pain may influence the sympathetic-adrenal-medullary (SAM) system, which contributes to cardiovascular responses to stress and also exhibits altered responsiveness in the presence of pain. The purpose of this study was to investigate the relationship between HPA activity during the cortisol awakening response and cardiovascular reactivity during exposure to an acute psychological stressor in individuals with chronic neck pain.

Examination of contraction-induced muscle pain as a behavioral correlate of physical activity in women with and without fibromyalgia.

Purpose: This study aimed to compare muscle pain intensity during a sustained isometric contraction in women with and without fibromyalgia (FM), and examine the association between muscle pain and self-reported levels of physical activity.

Methods: Fourteen women with FM and 14 healthy women completed the study, where muscle pain ratings (MPRs) were obtained every 30 s during a 3 min isometric handgrip task at 25% maximal strength, and self-reported physical activity was quantified using the Baecke Physical Activity Questionnaire.

Results: Women with FM were less physically active than healthy controls.

Effects of electrocardiography contamination and comparison of ECG removal methods on upper trapezius electromyography recordings.

Electromyography (EMG) recordings from the trapezius are often contaminated by the electrocardiography (ECG) signal, making it difficult to distinguish low-level muscle activity from muscular rest. This study investigates the influence of ECG contamination on EMG amplitude and frequency estimations in the upper trapezius during muscular rest and low-level contractions. A new method of ECG contamination removal, filtered template subtraction (FTS), is described and compared to 30 Hz high-pass filter (HPF) and averaged template subtraction (ATS) methods.

Associations between cervical and scapular posture and the spatial distribution of trapezius muscle activity.

The first aim of this investigation was to quantify the distribution of trapezius muscle activity with different scapular postures while seated. The second aim of this investigation was to examine the association between changes in cervical and scapular posture when attempting to recruit different subdivisions of the trapezius muscle. Cervical posture, scapular posture, and trapezius muscle activity were recorded from 20 healthy participants during three directed shoulder postures.

Modulation of intracortical inhibition in response to acute psychosocial stress is impaired among individuals with chronic neck pain.

Objective: Psychosocial stress has been associated with a variety of chronic pain disorders although the mechanisms responsible for this relationship are unknown. The purpose of this study was to compare the excitability of intracortical and corticospinal pathways to the trapezius muscle in individuals with and without chronic neck pain during exposure to low and high levels of psychosocial stress.

Methods: Single and paired-pulse transcranial magnetic stimulation was used to assess motor evoked potentials (MEPs) and short-interval intracortical inhibition (SICI) during mental math performed in the presence and absence of social evaluative threat.

Future directions in painful knee osteoarthritis: harnessing complexity in a heterogeneous population.

This perspective article proposes a conceptual model for the pain experience for individuals diagnosed with knee osteoarthritis (OA). Pain in knee OA is likely a heterogeneous, multifactorial phenomenon that involves not only the OA disease process but also elements specific to patient psychology and pain neurophysiology. The relevant contributions to the pain experience for any individual patient remain difficult, if not impossible, to definitively determine, and the rationale for many clinical treatment decisions arises primarily from a mechanistic understanding of OA pathophysiology.

Pain mediates the association between physical activity and the impact of fibromyalgia on daily function.

This study quantified the association between recreational physical activity and daily function in women with fibromyalgia, and determined if this association is mediated by symptoms of pain, depression, or body mass. Twenty-three women diagnosed with fibromyalgia participated in an observational survey study. Recreational physical activity and the impact of fibromyalgia on daily function were assessed using the sport and leisure time physical activity subscales of the Baecke Physical Activity Questionnaire (BPAQ) and the Fibromyalgia Impact Questionnaire (FIQ), respectively.

Mechanical pain sensitivity and the severity of chronic neck pain and disability are not modulated across the menstrual cycle.

Unlabelled: Despite the high prevalence of neck pain among women, menstrual effects on regional pain outcomes have not been investigated in this clinical population. This study evaluated menstrual effects on mechanical pain sensitivity (pressure pain threshold [PPT]), neck pain intensity (numeric pain rating scale [NPRS]), and neck-related disability (Neck Disability Index [NDI]) in 22 normally menstruating (NM) and 17 hormonal contraceptive users with chronic neck pain. Sex hormones, PPT, and NDI were measured during the early follicular (F1), late follicular (F2), and luteal (L) menstrual phases.

Differential effects of mental concentration and acute psychosocial stress on cervical muscle activity and posture.

Physical and psychosocial stressors in the workplace have been independently associated with the development of neck pain, yet interactions among these risk factors remain unclear. The purpose of this study was to compare the effects of mentally challenging computer work performed with and without exposure to a psychosocial stressor on cervical muscle activity and posture. Changes in cervical posture and electromyography of upper trapezius, cervical extensor, and sternocleidomastoid muscles were compared between a resting seated posture at baseline, a low stress condition with mental concentration, and a high stress condition with mental concentration and psychosocial stress in sixty healthy office workers.

Preliminary investigation of absent nociceptive flexion reflex responses among more symptomatic women with fibromyalgia syndrome.

Fibromyalgia syndrome (FMS) is a widespread musculoskeletal pain condition with unclear physiologic mechanisms. The purpose of this investigation was to compare the responsiveness of nociceptive flexion reflex (NFR) pathways between women with and without FMS. A secondary purpose was to examine the influence of depression, fibromyalgia symptom severity, and cardiovascular health on NFR responses among women with FMS.

Reliability and group differences in quantitative cervicothoracic measures among individuals with and without chronic neck pain.

Background: Clinicians frequently rely on subjective categorization of impairments in mobility, strength, and endurance for clinical decision-making; however, these assessments are often unreliable and lack sensitivity to change. The objective of this study was to determine the inter-rater reliability, minimum detectable change (MDC), and group differences in quantitative cervicothoracic measures for individuals with and without chronic neck pain (NP).

Methods: Nineteen individuals with NP and 20 healthy controls participated in this case control study.

Stress management as an adjunct to physical therapy for chronic neck pain.

Background And Purpose: Chronic neck pain is prevalent in the workplace. Research suggests that psychosocial stress may contribute to the development of neck pain by causing excessive or prolonged muscle activity in some individuals. The purpose of this case report is to describe the rationale, development, and implementation of stress management as an adjunct to standard physical therapist management of chronic neck pain in a female office worker who responded to psychosocial stress with elevated muscle activity prior to treatment.

Dependence of the paired motor unit analysis on motor unit discharge characteristics in the human tibialis anterior muscle.

The paired motor unit analysis provides in vivo estimates of the magnitude of persistent inward currents (PIC) in human motoneurons by quantifying changes in the firing rate (ΔF) of an earlier recruited (reference) motor unit at the time of recruitment and derecruitment of a later recruited (test) motor unit. This study assessed the variability of ΔF estimates, and quantified the dependence of ΔF on the discharge characteristics of the motor units selected for analysis. ΔF was calculated for 158 pairs of motor units recorded from nine healthy individuals during repeated submaximal contractions of the tibialis anterior muscle.