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Introduction: When performing an exercise or a functional test, pain that is evoked by movement or muscle contraction could be a stronger stimulus for changing how individuals move compared to tonic pain. We investigated whether the decrease in muscle force production is larger when experimentally‐induced knee pain is directly associated to the torque produced (movement‐evoked) compared to a constant painful stimulation (tonic). Methods: Twenty‐one participants performed three isometric knee extension maximal voluntary contractions without pain (baseline), during pain, and after pain. Knee pain was induced using sinusoidal electrical stimuli at 10 Hz over the infrapatellar fat pad, applied continuously or modulated proportionally to the knee extension torque. Peak torque and contraction duration were averaged across repetitions and normalized to baseline. Results: During tonic pain, participants reported lower pain intensity during the contraction than at rest (p < 0.001), whereas pain intensity increased with contraction during movement‐evoked pain (p < 0.001). Knee extension torque decreased during both pain conditions (p < 0.001), but a larger reduction was observed during movement‐evoked compared to tonic pain (p < 0.001). Participants produced torque for longer during tonic compared to movement‐evoked pain (p = 0.005). Conclusion: Our results indicate that movement‐evoked pain was a more potent stimulus to reduce knee extension torque than tonic pain. The longer contraction time observed during tonic pain may be a result of a lower perceived pain intensity during muscle contraction. Overall, our results suggest different motor adaptation to tonic and movement‐evoked pain and support the notion that motor adaptation to pain is a purposeful strategy to limit pain. This mechanistic evidence suggests that individuals experiencing prevalently tonic or movement‐evoked pain may exhibit different motor adaptations, which may be important for exercise prescription. [ABSTRACT FROM AUTHOR]

Background and Aims: Pain drawings are commonly used in the clinical assessment of people with cervical radiculopathy. This study aimed to assess (1) the agreement of clinical interpretation of pain drawings and MRI findings in identifying the affected level of cervical radiculopathy, (2) the agreement of these predictions based on the pain drawing among four clinicians from two different professions (i.e., physiotherapy and surgery) and (3) the topographical pain distribution of people presenting with cervical radiculopathy (C4–C7). Methods: Ninety‐eight pain drawings were obtained from a baseline assessment of participants in a randomized clinical trial, in which single‐level cervical radiculopathy was determined using MRI. Four experienced clinicians independently rated each pain drawing, attributing the pain distribution to a single nerve root (C4–C7). A post hoc analysis was performed to assess agreement. Outcome measures: Percentage agreement and kappa values were used to assess the level of agreement. Topographic pain frequency maps were created for each cervical radiculopathy level as determined by MRI. Results: The radiculopathy level determined from the pain drawings showed poor overall agreement with MRI (mean = 35.7%, K = −0.007 to 0.139). The inter‐clinician agreement ranged from fair to moderate (K = 0.212–0.446). Topographic frequency maps revealed that pain distributions were widespread and overlapped markedly between patients presenting with different levels cervical radiculopathy. Conclusion: This study revealed a lack of agreement between the segmental level affected determined from the patient's pain drawing and the affected level as identified on MRI. The large overlap of pain and non‐dermatomal distribution of pain reported by patients likely contributed to this result. [ABSTRACT FROM AUTHOR]

Sensitization mechanisms are thought to play a role in the perception of pain in people with cluster headache. No study has investigated the relation between the spatial extent of pain in cluster headache and measures of sensitization or other clinical features. Our aim was to investigate if the size of the painful area in people with cluster headache relates to widespread pressure sensitivity, headache features, and psychological outcomes. Forty men with episodic cluster headache reported their symptoms on a digital body chart and pain extent was calculated. Pressure pain thresholds were assessed locally over the temporalis muscle and the C5-C6 joint and at a remote site over the tibialis anterior to assess widespread pressure sensitivity. Clinical features of headache attacks, and anxiety/depressive levels were also assessed. Patients were assessed during a period of remission 6 months after their last pain attack and after treatment discontinuation. Thirty-two (80%) and thirty (75%) patients reported their headaches in the orbital and the frontal areas, respectively. No significant associations (rho values ranging from −0.228 to 0.187, P values ranging from 0.157 to 0.861) were found between pain extent and pressure pain thresholds in trigeminal, extra-trigeminal, and distant pain-free areas, headache clinical features, and anxiety and depressive levels. Pain extent in the trigemino-cervical area was not related to the degree of pressure pain sensitivity or headache features in men with episodic cluster headache during a period of remission. [ABSTRACT FROM AUTHOR]

Objective. Our aims were 1) to investigate whether perceived pain extent, assessed from the pain drawing, relates to clinical, psychological, and psychophysical outcomes in women with carpal tunnel syndrome (CTS); 2) to assess differences in pain extent depending on the presence of median or extramedian symptoms; and 3) to investigate differences in pain extent according to severity (minimal, moderate, or severe) or laterality (unilateral or bilateral) of CTS. Methods. One hundred forty (N�0) women with CTS completed pain drawings, which were subsequently digitized, allowing pain extent to be calculated. Clinical features including pain intensity (numerical pain rating scale, 0�) and disability (Boston Carpal Tunnel Questionnaire), psychological features including depression (Beck Depression Inventory), and psychophysical variables (pressure pain and thermal pain thresholds) were assessed. Spearman rho correlation coefficients were used to reveal the correlations between pain extent and other outcomes. Differences in pain extent according to severity (minimal, moderate, severe) or laterality (unilateral, bilateral) and the presence of extramedian symptoms were also evaluated. Results. No significant associations were identified between pain extent and clinical, psychological, or psychophysical outcomes. Women with extramedian symptoms (88%) exhibited a larger (P<0.001) pain extent (total: 24.2%613.5%) than women with median symptoms (12%; total: 12.2%66.9%). Pain extent was not significantly different depending on the severity or laterality of the symptoms. Conclusions. Pain extent in the upper extremity was not associated with clinical, psychological, or psychophysical variables and was not related to the severity or laterality of the symptoms in women with CTS. [ABSTRACT FROM AUTHOR]

Objective: To determine the efficacy of suboccipital inhibitory techniques in people with migraine compared with a control treatment based on myofascial trigger point (MTrP) therapy and stretching. Design: A randomized, double-blind controlled pilot trial was conducted. Settings/Location: University research laboratory. Subjects: Forty-six adults diagnosed with migraine with over 6 months duration. Interventions: Participants were randomized to receive either combined MTrP therapy and stretching (control group) or the control treatment plus suboccipital soft tissue inhibition (experimental group). Treatment was applied on four occasions over 8 weeks (one every 15 days), with a duration of 30 minutes per session in the experimental group and 20 min in the control group. Outcome measures: The impact of headache was assessed with the Headache Impact Test (HIT-6), disability by the migraine disability assessment (MIDAS), and quality of life by the Short Form Health Survey (SF-36). Both groups were assessed at baseline and 1 week immediately after the end of treatment. Results: The amount of change of the HIT-6 score and MIDAS scores were significantly different between groups (p < 0.05), although the SF-36 scores were not. The change in the HIT-6 score and MIDAS scores was greater in the experimental group. Both groups showed a reduction on the HIT-6 score (p < 0.001), MIDAS scores (p < 0.05), and SF-36 physical subscale, whereas the SF-36 mental subscale improved only in the experimental group (p < 0.001). Conclusion: Soft tissue techniques based on MTrP therapy and stretching were helpful for improving certain aspects of migraine, such as the impact and disability caused by the headache, and the frequency and intensity of headache; however, when combined with suboccipital soft tissue inhibition, the treatment effect was larger. [ABSTRACT FROM AUTHOR]

STUDY DESIGN: Longitudinal clinimetric study. BACKGROUND: Pain self-efficacy predicts poor recovery and mediates the relationship between pain and disability in patients with neck pain disorders (NPDs). The Pain Self-Efficacy Questionnaire (PSEQ) is a frequently used instrument to measure pain self-efficacy; however, its measurement properties have never been evaluated in a group of patients with NPDs. OBJECTIVES: This study aimed to assess validity and responsiveness of the PSEQ in patients with NPDs. METHODS: Patients with NPDs (n = 161) were included. Confirmatory and exploratory factor analysis was used to assess structural validity. Twelve hypotheses on expected correlations with other instruments were formulated a priori to assess construct validity. Responsiveness was evaluated in 146 patients with NPDs who underwent multimodal rehabilitation by testing 12 hypotheses on expected effect sizes, area under the curve, and correlations with change in other instruments. RESULTS: Factor analyses showed that the PSEQ is a unidimensional instrument with moderate construct validity and responsiveness (50% to 75% of hypotheses met). Validity was consistent when analyzed separately for patients with whiplash-associated disorders and idiopathic neck pain, and responsiveness was better in patients with idiopathic neck pain. CONCLUSION: The PSEQ is a unidimensional measure of pain self-efficacy in patients with NPDs, as found by previous studies in other populations. Nevertheless, in contrast with previous studies, its construct validity and responsiveness were found to be suboptimal in NPDs, suggesting that the content validity of the PSEQ and of the comparator instruments used in this study should be better assessed. [ABSTRACT FROM AUTHOR]

Background. Expanded distribution of pain is considered a sign of central sensitization (CS). The relationship between recording of symptoms and CS in people with knee osteoarthritis (OA) has been poorly investigated. Objective. The aim of this study was to examine whether the area of pain assessed using pain drawings relates to CS and clinical symptoms in people with knee OA. Design. This was a cross-sectional study. Methods. Fifty-three people with knee OA scheduled to undergo primary total knee arthroplasty were studied. All participants completed pain drawings using a novel digital device, completed self-administration questionnaires, and were assessed by quantitative sensory testing. Pain frequency maps were generated separately for women and men. Spearman correlation coefficients were computed to reveal possible correlations between the area of pain and quantitative sensory testing and clinical symptoms. Results. Pain frequency maps revealed enlarged areas of pain, especially in women. Enlarged areas of pain were associated with higher knee pain severity (rs=.325, P<.05) and stiffness (rs=.341, P<.05), lower pressure pain thresholds at the knee (rs= -.306, P<.05) and epicondyle (rs=-.308, P<05), and higher scores with the Central Sensitization Inventory (rs=.456, P<.01). No significant associations were observed between the area of pain and the remaining clinical symptoms and measures of CS. Limitations. Firm conclusions about the predictive role of pain drawings cannot be drawn. Further evaluation of the reliability and validity of pain area extracted from pain drawings in people with knee OA is needed. Conclusion. Expanded distribution of pain was correlated with some measures of CS in individuals with knee OA. Pain drawings may constitute an easy way for the early identification of CS in people with knee OA, but further research is needed. [ABSTRACT FROM AUTHOR]

STUDY DESIGN: A prospective cohort study nested in a randomized controlled trial. OBJECTIVES: To determine and compare responsiveness and minimal clinically important change of the modified Constant score (CS) and the Oxford Shoulder Score (OSS). BACKGROUND: The OSS and the CS are commonly used to assess shoulder outcomes. However, few studies have evaluated the measurement properties of the OSS and CS in terms of responsiveness and minimal clinically important change. METHODS: The study included 126 patients who reported having difficulty returning to usual activities 8 to 12 weeks after arthroscopic decompression surgery for subacromial impingement syndrome. The assessment at baseline and at 3 months included the OSS, the CS, and the European Quality of Life-5 Dimensions-3 Level (EQ- 5D-3L) index. Responsiveness was assessed as follows: by correlation analysis between the change scores of the OSS, CS, and EQ-5D-3L index, and the Patient Global Impression of Change (PGIC) scale; by receiver-operating-characteristic (ROC) curve analysis using the PGIC scale as an external anchor; and by effect-size statistics. RESULTS: At 3 months, a follow-up assessment of 112 patients (89%) was conducted. The change scores of the CS and the OSS were more strongly correlated with the external anchor (PGIC scale) than the change score of the EQ-5D-3L index. The areas under the ROC curves exceeded 0.80 for both shoulder scores, with no significant differences between them, and comparable effect-size estimates were observed for the CS and the OSS. Minimal clinically important change ROC values were 6 points for the OSS and 11 points for the CS, with upper 95% cutoff limits of 12 and 22 points, respectively. CONCLUSION: The CS and the OSS were both suitable for assessing improvement after decompression surgery. [ABSTRACT FROM AUTHOR]

Objective: The purpose of this study was to investigate the effect of active vs passive scapular correction on pain and pressure pain threshold at the most symptomatic cervical segment in patients with chronic neck pain. Methods: Twenty-three volunteers with chronic, idiopathic neck pain were recruited (age, 38.9 ± 14.4 years; sex [man/woman], 3/20; Neck Disability Index, 28.1% ± 9.9%). Subjects were randomly allocated to 2 groups: active scapular correction or passive scapular correction. Pressure pain threshold and pain intensity rated on a numerical rating scale during a posteroanterior glide over the most symptomatic cervical segment were measured before and immediately after the active or passive scapular intervention. Results: Only the active scapular correction produced a reduction in pain (pre, 6.3 ± 1.2; post, 3.7 ± 2.4; P< .05) and increase in pressure pain threshold (pre, 8.7 ± 4.2 kg/cm²; post, 10.1 ± 3.8 kg/cm²; P < .05) at the most painful cervical segment. Conclusions: An active scapular correction exercise resulted in an immediate reduction of pain and pressure pain sensitivity in patients with chronic neck pain and scapular dysfunction. [ABSTRACT FROM AUTHOR]

The article focuses on one study which investigates the action potential propagation velocity in individual motor units before and after the performance of eccentric exercise. 10 healthy men were recruited for the study and were asked to perform the eccentric exercise which consists of a series of four sets of 25 repetitions with three-minute rest between each set. Sensory assessment of muscle pain, EMG recordings, data analysis, statistical analysis were the conducted after the performance. After data interpretation, it was revealed that the electrophysiological membrane properties of muscle fibers are altered by exercise-induced muscle fiber damage.

High-density surface electromyography (HDsEMG) can be used to measure the spatial distribution of electrical muscle activity over the skin. As this distribution is associated with the generation and propagation of muscle fiber action potentials, HDsEMG is processed to extract information on regional muscle activation, muscle fiber characteristics and behaviour of individual motor units. This matrix, developed by the Consensus for Experimental Design in Electromyography (CEDE) project, summarizes recommendations on the use of HDsEMG in experimental studies. For each application, recommendations are included regarding electrode montage, electrode type and configuration, electrode location and orientation, data analysis, and interpretation. Cautions and reporting standards are also included. The steps of the Delphi process to reach consensus are contained in an appendix. This matrix is intended to help researchers when collecting, reporting, and interpreting HDsEMG data. It is hoped that this document will be used to generate new empirical evidence to improve how HDsEMG is used in research and in clinical applications. [ABSTRACT FROM AUTHOR]

The article presents a study which examines the effects of 24 and 48 hours eccentric exercise in the reflex activity of knee muscles to rapid destabilizing perturbations. The study used KinCom Dynamometer to measure the maximal voluntary isometric contraction force while the perceived pain intensity 24 and 48 hours after exercise was assessed a 10-cm scale visual analog scale. Results show that time to task failure and significant decreases in maximum voluntary force. Furthermore, average rectified value (ARV) depended on the perturbation direction and the interaction between session and muscle during the rapid destabilizing perturbations.