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Chronic low back pain (CLBP) is a disabling condition worldwide. In CLBP, neuroimaging studies demonstrate abnormal activities in cortical areas responsible for pain modulation, emotional, and sensory components of pain experience [i.e.,... more
Chronic low back pain (CLBP) is a disabling condition worldwide. In CLBP, neuroimaging studies demonstrate abnormal activities in cortical areas responsible for pain modulation, emotional, and sensory components of pain experience [i.e., pregenual and dorsal anterior cingulate cortex (pgACC, dACC), and somatosensory cortex (SSC), respectively]. This pilot study, conducted in a university setting, evaluated the feasibility, safety, and acceptability of a novel electroencephalography-based infraslow-neurofeedback (EEG ISF-NF) technique for retraining activities in pgACC, dACC and SSC and explored its effects on pain and disability. Participants with CLBP (n = 60), recruited between July’20 to March’21, received 12 sessions of either: ISF-NF targeting pgACC, dACC + SSC, a ratio of pgACC*2/dACC + SSC, or Placebo-NF. Descriptive statistics demonstrated that ISF-NF training is feasible [recruitment rate (7 participants/month), dropouts (25%; 20–27%), and adherence (80%; 73–88%)], safe (no...
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Electroencephalographic (EEG) alterations have been demonstrated in acute, chronic, and experimentally induced musculoskeletal (MSK) pain conditions. However, there is no cumulative evidence on the associated EEG characteristics... more
Electroencephalographic (EEG) alterations have been demonstrated in acute, chronic, and experimentally induced musculoskeletal (MSK) pain conditions. However, there is no cumulative evidence on the associated EEG characteristics differentiating acute, chronic, and experimentally induced musculoskeletal pain states, especially compared to healthy controls. The present systematic review was performed according to the Preferred Reporting Items for Systematic reviews and Meta-Analyses guidelines (PRISMA) to review and summarize available evidence for cortical brain activity and connectivity alterations in acute, chronic, and experimentally induced MSK pain states. Five electronic databases were systematically searched from their inception to 2022. A total of 3471 articles were screened, and 26 full articles (five studies on chronic pain and 21 studies on experimentally induced pain) were included for the final synthesis. Using the Downs and Black risk of assessment tool, 92% of the stud...
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This study explored the effect of electroencephalographic infraslow neurofeedback (EEG ISF-NF) training on effective connectivity and tested whether such effective connectivity changes are correlated with changes in pain and disability in... more
This study explored the effect of electroencephalographic infraslow neurofeedback (EEG ISF-NF) training on effective connectivity and tested whether such effective connectivity changes are correlated with changes in pain and disability in people with chronic low back pain. This involved secondary analysis of a pilot double-blinded randomised placebo-controlled study. Participants (n = 60) were randomised to receive ISF-NF targeting either the pregenual anterior cingulate cortex (pgACC), dorsal anterior cingulate and somatosensory cortex (dACC + S1), ratio of pgACC*2/dACC + S1, or Sham-NF. Resting-state EEG and clinical outcomes were assessed at baseline, immediately after intervention, and at one-week and one-month follow-up. Kruskal–Wallis tests demonstrated significant between-group differences in effective connectivity from pgACC to S1L at one-month follow up and marginal significant changes from S1L to pgACC at one-week and one-month follow up. Mann–Whitney U tests demonstrated ...
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Tinnitus is defined as the conscious awareness of a sound without an identifiable external sound source, and tinnitus disorder as tinnitus with associated suffering. Chronic tinnitus has been anatomically and phenomenologically separated... more
Tinnitus is defined as the conscious awareness of a sound without an identifiable external sound source, and tinnitus disorder as tinnitus with associated suffering. Chronic tinnitus has been anatomically and phenomenologically separated into three pathways: a lateral “sound” pathway, a medial “suffering” pathway, and a descending noise-canceling pathway. Here, the triple network model is proposed as a unifying framework common to neuropsychiatric disorders. It proposes that abnormal interactions among three cardinal networks—the self-representational default mode network, the behavioral relevance-encoding salience network and the goal-oriented central executive network—underlie brain disorders. Tinnitus commonly leads to negative cognitive, emotional, and autonomic responses, phenomenologically expressed as tinnitus-related suffering, processed by the medial pathway. This anatomically overlaps with the salience network, encoding the behavioral relevance of the sound stimulus. Chron...
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Background: The core intrinsic connectivity networks (ICNs), encompassing the default-mode network (DMN), salience network (SN) and central executive network (CEN), have been shown to be dysfunctional in individual’s with internalizing... more
Background: The core intrinsic connectivity networks (ICNs), encompassing the default-mode network (DMN), salience network (SN) and central executive network (CEN), have been shown to be dysfunctional in individual’s with internalizing disorders (IDs; e.g. major depressive disorder, MDD; generalized anxiety disorder, GAD; social anxiety disorder, SOC). As such, source-localised electroencephalogram neurofeedback (EEG-NFB) therapy targeting key cortical nodes within these networks has the potential to reduce symptoms associated with IDs and restore normal core ICN function. We intend to conduct a transdiagnostic, randomized, double-blind, sham-controlled, dose-response, parallel-group trial of standardized low-resolution electromagnetic tomography electrophysiological infraslow (<0.1 Hz) fluctuation neurofeedback (sLORETA eISF-NFB) 3 times per week over 4 weeks in participants (n=60) with IDs. Our primary aim will be to assess the clinical efficacy of sLORETA eISF-NFB via relevant...
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As for hypertension, chronic pain, epilepsy and other disorders with particular symptoms, a commonly accepted and unambiguous definition provides a common ground for researchers and clinicians to study and treat the problem. The WHO's... more
As for hypertension, chronic pain, epilepsy and other disorders with particular symptoms, a commonly accepted and unambiguous definition provides a common ground for researchers and clinicians to study and treat the problem. The WHO's ICD11 definition only mentions tinnitus as a nonspecific symptom of a hearing disorder, but not as a clinical entity in its own right, and the American Psychiatric Association's DSM-V doesn't mention tinnitus at all. Here we propose that the tinnitus without and with associated suffering should be differentiated by distinct terms: "Tinnitus" for the former and "Tinnitus Disorder" for the latter. The proposed definition then becomes "Tinnitus is the conscious awareness of a tonal or composite noise for which there is no identifiable corresponding external acoustic source, which becomes Tinnitus Disorder "when associated with emotional distress, cognitive dysfunction, and/or autonomic arousal, leading to behavioural changes and functional disability.". In other words "Tinnitus" describes the auditory or sensory component, whereas "Tinnitus Disorder" reflects the auditory component and the associated suffering. Whereas acute tinnitus may be a symptom secondary to a trauma or disease, chronic tinnitus may be considered a primary disorder in its own right. If adopted, this will advance the recognition of tinnitus disorder as a primary health condition in its own right. The capacity to measure the incidence, prevalence, and impact will help in identification of human, financial, and educational needs required to address acute tinnitus as a symptom but chronic tinnitus as a disorder.
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The pathophysiological mechanisms that underlie the generation and maintenance of tinnitus are being unraveled progressively. Based on this knowledge, a large variety of different neuromodulatory interventions have been developed and are... more
The pathophysiological mechanisms that underlie the generation and maintenance of tinnitus are being unraveled progressively. Based on this knowledge, a large variety of different neuromodulatory interventions have been developed and are still being designed, adapting to the progressive mechanistic insights in the pathophysiology of tinnitus. rTMS targeting the temporal, temporoparietal, and the frontal cortex has been the mainstay of non-invasive neuromodulation. Yet, the evidence is still unclear, and therefore systematic meta-analyses are needed for drawing conclusions on the effectiveness of rTMS in chronic tinnitus. Different forms of transcranial electrical stimulation (tDCS, tACS, tRNS), applied over the frontal and temporal cortex, have been investigated in tinnitus patients, also without robust evidence for universal efficacy. Cortex and deep brain stimulation with implanted electrodes have shown benefit, yet there is insufficient data to support their routine clinical use. Recently, bimodal stimulation approaches have revealed promising results and it appears that targeting different sensory modalities in temporally combined manners may be more promising than single target approaches.While most neuromodulatory approaches seem promising, further research is required to help translating the scientific outcomes into routine clinical practice.
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ABSTRACT Objective: Fitbit Zip™ (FBZ) is a low-cost user-friendly device that could help motivate individuals post-stroke to increase their physical activity. However, inaccuracy in step counts from altered gait variables could cause... more
ABSTRACT Objective: Fitbit Zip™ (FBZ) is a low-cost user-friendly device that could help motivate individuals post-stroke to increase their physical activity. However, inaccuracy in step counts from altered gait variables could cause dissatisfaction and reduce compliance. The aim of this study was to determine the influence of gait variables on the concurrent validity of the FBZ. Method: In a cross-sectional study, 19 community-dwelling stroke survivors (mean 66 (SD 8) years) wore a FBZ at the non-paretic hip, and were videoed completing a six minute walk test (6MWT). Steps recorded by the FBZ were compared against the criterion standard of manually counted steps from video-recordings. Spatio-temporal gait parameters were calculated, and gait quality was assessed using the Wisconsin Gait Analysis (WGA) tool. Concurrent validity of FBZ was determined using Kendall’s Tau correlation coefficient. Linear regression analysis determined the association between gait parameters, quality, and FBZ accuracy. Results: A very strong correlation was observed between the FBZ steps and manual counting (τ = 0.80, p < .001). Step difference demonstrated significant negative association with gait velocity (R2 = 0.35, B = −59.94, p = .007), and positive association with WGA score (R2 = 0.69, B = 4.59, p < .001), indicating poor FBZ accuracy in participants with lower speed (≤0.8m/s) and poor gait quality (WGA score>16). Conclusions: FBZ is an accurate measure of step activity in independent ambulators with stroke walking at speeds > 0.8m/s, but accuracy can be compromised with lower speed and poor gait quality. Clinicians should consider gait velocity and quality before advising FBZ as a motivational tool to increase physical activity in individuals post-stroke.
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OBJECTIVES To determine normal temperatures over the Achilles tendon over nine weeks. DESIGN A prospective cohort study with nine weeks of observation. SETTING University's Human Biomechanics and Physiology Laboratory. PARTICIPANTS... more
OBJECTIVES To determine normal temperatures over the Achilles tendon over nine weeks. DESIGN A prospective cohort study with nine weeks of observation. SETTING University's Human Biomechanics and Physiology Laboratory. PARTICIPANTS Male or female competitive runners running at least 25 miles per week who did not report pain in the region of the Achilles over 9 weeks of data collection. MAIN OUTCOME MEASURE Thermal images taken at the same time and day of the week, were used to measure the temperature of the skin over the Achilles tendon. RESULTS Seventeen athletes were eligible for analysis. The Achilles tendon temperatures were right 28.7 °C ± 1.3 °C, left 28.8 °C ± 1.3 °C. ICC demonstrated a very high consistency and minimal variations in temperatures (right 0.86 (95% CI = 0.58, 0.98), left 0.79 (95% CI = 0.38, 0.97). The mean difference between sides over the season was 0.50 °C ± 0.43 °C (p = 0.681). A decreasing trend in the Achilles tendon temperatures as the season progressed was observed. CONCLUSION This is the first report of normal thermal profiles over an extended period. Variations in Achilles temperatures left to right, and over time were not significant. The decreasing temperature trend over the season warrants further investigation.
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BACKGROUND Normalizing to a reference signal is essential when analysing and comparing electromyography signals across or within individuals. However, studies have shown that MVC testing may not be as reliable in persons with acute and... more
BACKGROUND Normalizing to a reference signal is essential when analysing and comparing electromyography signals across or within individuals. However, studies have shown that MVC testing may not be as reliable in persons with acute and chronic pain. OBJECTIVES The purpose of this study was to compare the test-retest reliability of the muscle activity in the biceps femoris and gluteus maximus between a novel sub-MVC and standard MVC protocols. METHODS This study utilized a single individual repeated measures design with 12 participants performing multiple trials of both the sub-MVC and MVC tasks on two separate days. The participant position in the prone leg raise task was standardised with an ultrasonic sensor to improve task precession between trials/days. Day-to-day and trial-to-trial reliability of the maximal muscle activity was examined using ICC and SEM. FINDINGS Day-to-day and trial-to-trial reliability of the EMG activity in the BF and GM were high (0.70-0.89) to very high (≥0.90) for both test procedures. %SEM was <5-10% for both tests on a given day but higher in the day-to-day comparisons. The lower amplitude of the sub-MVC is a likely contributor to increased %SEM (8-13%) in the day-to-day comparison. CONCLUSIONS The findings show that the sub-MVC modified prone double leg raise results in GM and BF EMG measures similar in reliability and precision to the standard MVC tasks. Therefore, the modified prone double leg raise may be a useful substitute for traditional MVC testing for normalizing EMG signals of the BF and GM.
Background: Physiotherapy plays an important role in management of acute nonspecific low back pain (NSLBP). However, there is a relative dearth of information about the current clinical practice for management of NSLBP and its... more
Background: Physiotherapy plays an important role in management of acute nonspecific low back pain (NSLBP). However, there is a relative dearth of information about the current clinical practice for management of NSLBP and its relationships with clinical outcomes of pain and function. Objective: To investigate the current physiotherapy practice patterns in management of acute NSLBP in New Zealand (NZ), and determine its relationships with clinical outcomes of pain and function. Methods: A prospective observational cohort study, using data from private physiotherapy clinics, was conducted. Physiotherapists at each clinic completed a treatment summary form at time of discharge. Treatment techniques used and clinical outcome of pain [numeric pain rating scale (NPRS)] and function [Patient-specific Function scale (PSFS)] were extracted from recorded notes. Raw values of NPRS and PSFS were converted to percentage of available change scores and used for further analysis. Results and Conclusions: A total of 199 data-sets of acute NSLBP patients were included in the analysis. A wide variety of treatment techniques were used by NZ physiotherapists, with joint mobilization being the most popular form of treatment choice (88%), often combined with specific exercises and massage (21%). Linear regression analysis demonstrated a significant positive association between joint mobilization and massage and patient’s function, and pain and function, respectively; whereas, a significant negative association between specific exercises and patient’s function. The most popular form of treatments used by NZ physiotherapists’ lacks support from evidence-based clinical guidelines, but still seems to be effective in reducing pain and improving function.
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Palpation-digitization technique for measurement of innominate motion involves repeated manual palpation-digitization of pelvic landmarks, which could introduce a systematic variation between subsequent trials and thereby influence final... more
Palpation-digitization technique for measurement of innominate motion involves repeated manual palpation-digitization of pelvic landmarks, which could introduce a systematic variation between subsequent trials and thereby influence final innominate angular measurement. The aim of this study is to quantify the effect of repeated palpation-digitization errors on overall variability of innominate vector length measurements; and to determine if there is a systematic variation between subsequent repeated trials. A single group repeated measures study, using four testers and fourteen healthy participants, was conducted. Four pelvic landmarks, left and right posterior superior iliac spine and anterior superior iliac spine, were palpated and digitized using 3D digitizing stylus of Polhemus electromagnetic tracking device, for ten consecutive trials by each tester in their random order. The ten individual trials of innominate vector lengths measured by each tester for each participant were used for the analysis. Repeated measures ANOVA demonstrated a very small effect of repeated trial factor (≤0.66%) as well as error component (≤0.32%) on innominate vector length variability. Further, residual versus order plots demonstrated a random pattern of errors across zero; thus indicating no systematic variation between subsequent trials of innominate vector length measurements.
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Research Interests: Manual Therapy, Adolescent, Medicine, Low back pain, Prospective studies, and 15 moreHumans, Female, Male, New Zealand, Clinical Sciences, Middle Aged, Adult, Pelvic Pain, Rotation, Elsevier, Sensitivity and Specificity, Pain Measurement, Predictive value of tests, Biomechanical Phenomena, and Sacroiliac joint
Innominate kinematic anomalies resulting in low back pain (LBP) of sacroiliac joint (SIJ) origin (SIJ-positive), has always been a topic of contention, owing to difficultly in its evaluation. Recent technique of electromagnetic... more
Innominate kinematic anomalies resulting in low back pain (LBP) of sacroiliac joint (SIJ) origin (SIJ-positive), has always been a topic of contention, owing to difficultly in its evaluation. Recent technique of electromagnetic palpation-digitization has been able to accurately quantify innominate kinematics in healthy individuals. The purpose of this study is to determine if participants with LBP of SIJ origin (SIJ-positive) demonstrate significantly different innominate kinematics than participants with LBP of non-SIJ origin (SIJ-negative). Single-blinded cross-sectional case-control study. Participants [n(122)] between the ages of 18 to 50 years, suffering from chronic non-specific LBP (≥3 months) volunteered in the study. An experienced musculoskeletal physiotherapist evaluated and classified participants into either SIJ-positive [n(45)] or SIJ-negative [n(77)] group, using the reference standard pain provocation tests [≥3 positive tests = SIJ-positive]. A research physiotherapist, blinded to clinical groups, conducted the innominate kinematic testing using a valid and reliable electromagnetic palpation-digitization technique, during prone lying incremental hip abduction-external rotation test positions. The results of the mixed model regression analyses demonstrated that SIJ-positive participants exhibited significantly different innominate movement patterns and trends of rotation, but not innominate ranges of motion, when compared with SIJ-negative LBP participants. These findings demonstrate association between SIJ pain and altered innominate kinematics, and have led the groundwork for further exploration of clinical measurement, relevance, and management of these potentially important movement observations.
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Research Interests: Manual Therapy, Sensitivity Analysis, Adolescent, Medicine, Humans, and 15 moreKinematics, Female, Male, Reliability, Palpation, Motion, Clinical Sciences, Intraclass Correlation Coefficient, Repeated Measures, Observer Variation, Adult, Reproducibility of Results, Reference Values, Biomechanical Phenomena, and Sacroiliac joint
Joint kinematic assessment using an electromagnetic tracking device (EMTD) requires palpation-digitization (PD) of bony landmarks to define the anatomical axes. Errors in PD of bony landmarks can perturb the anatomical axes and affect the... more
Joint kinematic assessment using an electromagnetic tracking device (EMTD) requires palpation-digitization (PD) of bony landmarks to define the anatomical axes. Errors in PD of bony landmarks can perturb the anatomical axes and affect the validity and reliability of kinematic measurements. The validity and reliability of PD for kinematic measurement needs to be explored before recommending its wider use. A systematic search of 15 electronic databases located studies assessing validity and/or reliability of PD for joint kinematic assessment. Two independent reviewers used the QUADAS and QAREL tools to assess quality of validity and reliability studies respectively. The results were synthesized qualitatively using a level of evidence approach. Eight studies satisfied the final eligibility criteria and were included in the review. The validity, intra-rater reliability and inter-rater reliability were assessed in three, seven and one study respectively. The overall level of evidence for validity of PD technique was strong with high correlation (≥0.80) reported by three high (≥60%) quality studies. The overall level of evidence for intra-rater reliability was also strong with very high ICC (≥0.90) and satisfactory SEM (SEM% ≤ 10%) reported by four high quality studies. However the level of evidence for inter-rater reliability was limited and needs to be addressed by future research.
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Acute pain is a physiological response that causes an unpleasant sensory and emotional experience in the presence of actual or potential tissue injury. Anatomically and symptomatically, chronic pathological pain can be divided into three... more
Acute pain is a physiological response that causes an unpleasant sensory and emotional experience in the presence of actual or potential tissue injury. Anatomically and symptomatically, chronic pathological pain can be divided into three distinct but interconnected pathways, a lateral “painfulness” pathway, a medial “suffering” pathway and a descending pain inhibitory circuit. Pain (fullness) can exist without suffering and suffering can exist without pain (fullness). The triple network model is offering a generic unifying framework that may be used to understand a variety of neuropsychiatric illnesses. It claims that brain disorders are caused by aberrant interactions within and between three cardinal brain networks: the self-representational default mode network, the behavioral relevance encoding salience network and the goal oriented central executive network. A painful stimulus usually leads to a negative cognitive, emotional, and autonomic response, phenomenologically expressed...
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Pain is an unpleasant sensory and emotional experience associated with actual or potential tissue damage. Chronic pain, with a prevalence of 20-30% is the major cause of human suffering worldwide, because effective, specific and safe... more
Pain is an unpleasant sensory and emotional experience associated with actual or potential tissue damage. Chronic pain, with a prevalence of 20-30% is the major cause of human suffering worldwide, because effective, specific and safe therapies have yet to be developed. It is unevenly distributed among sexes, with women experiencing more pain and suffering. Chronic pain can be anatomically and phenomenologically dissected into three separable but interacting pathways, a lateral 'painfulness' pathway, a medial 'suffering' pathway and a descending pain inhibitory pathway. One may have pain(fullness) without suffering and suffering without pain(fullness). Pain sensation leads to suffering via a cognitive, emotional and autonomic processing, and is expressed as anger, fear, frustration, anxiety and depression. The medial pathway overlaps with the salience and stress networks, explaining that behavioural relevance or meaning determines the suffering associated with painfulness. Genetic and epigenetic influences trigger chronic neuroinflammatory changes which are involved in transitioning from acute to chronic pain. Based on the concept of the Bayesian brain, pain (and suffering) can be regarded as the consequence of an imbalance between the two ascending and the descending pain inhibitory pathways under control of the reward system. The therapeutic clinical implications of this simple pain model are obvious. After categorizing the working mechanisms of each of the available treatments (pain killers, psychopharmacology, psychotherapy, neuromodulation, psychosurgery, spinal cord stimulation) to 1 or more of the 3 pathways, a rational combination can be proposed of activating the descending pain inhibitory pathways in combination with inhibition of the medial and lateral pathway, so as to rebalance the pain (and suffering) pathways.