Search

Abstract. Introduction: We explored trajectories of pain intensity and depressive symptoms over the first 24 months of the pandemic in people with low back pain. Methods: This longitudinal study was conducted alongside the Quebec Low Back Pain Study. Starting in April 2020 and every 3 months until July 2022, 291 participants completed an online survey. Group-based trajectory modeling was used to identify patterns of pain intensity and depressive symptoms. Onset outbreak characteristics were then put in relation with trajectory groups using multivariate logistic regression. Results: The analysis revealed 5 trajectories of pain intensity and depressive symptoms, respectively. The pain trajectories were stable mild (n = 17, 5.8%); stable moderate (n = 103, 35.4%); stable severe (n = 81, 27.8%); U-shape (n = 24, 8.3%), and inverted U-shape (n = 66, 22.7%). The trajectories of depressive symptoms were stable none (n = 58, 19.9%); stable very mild (n = 61, 21.0%); stable mild (n = 85, 29.2%); stable moderate (n = 59, 21.7%); and severe slightly improving (n = 24, 8.3%). Pre-COVID everyday/nearly everyday pain, average pain intensity, and widespread bodily pain were predictive of pain trajectory groups. Higher pre-COVID depression, acute stress disorder, and lockdown measures-related stress were associated with moderate/severe depressive trajectories. Discussion: Our findings indicated relative stability of pain and depressive symptoms among participants during the COVID-19 pandemic but also highlighted subgroups of people who experienced temporary deterioration or improvement over the first months of the pandemic that then reverted back to baseline levels. Modifiable risk factors were identified before the onset of the pandemic, which could give preventive measures in targeted populations.

Background: A full-thickness rotator cuff tear (FTRCT) is defined as a complete tear of one of the four rotator cuff muscle tendons (supraspinatus, infraspinatus, subscapularis or teres minor). This condition can lead to pain and reduced function. However, not all FTRCT are symptomatic. A better understanding of the characteristics that lead some individuals with FTRCT to experience pain is fundamental to improve strategies used to manage this condition. This level II descriptive study aimed to explore potential sociodemographic, anatomical, psychosocial, pain sensitivity, biomechanical and neuromuscular variables that may differ between individuals with symptomatic FTRCT and age-matched individuals with asymptomatic shoulders. Methods: In this cross-sectional observational study, adults aged 50 to 80 years of age, either with symptomatic FTRCT or no shoulder pain, were recruited via convenience sampling. Participants filled out questionnaires on sociodemographic and psychosocial variables. Then, various tests were performed, including pain pressure threshold, shoulder range of motion, shoulder muscle strength, shoulder ultrasound and radiologic examination, and sensorimotor functions testing. Each variable was compared between groups using univariate analyses (independent t-tests, Mann-Whitney U tests, exact probability Fisher tests). Significance was set at 0.05. Results: FTRCT (n = 30) and Control (n = 30) groups were comparable in terms of sex, age, and number of comorbidities. The symptomatic FTRCT group showed a higher proportion of smokers (P = .026) and more participants indicated consuming alcohol or drugs more than they meant to (P = .010). The FTRCT group had a significantly higher prevalence of glenohumeral osteophytes (48% vs. 17%; P = .012). Participants in the FTRCT group were significantly more stressed (P = .04), anxious (P = .003) and depressed (P = .002). The FTRCT group also showed significantly higher levels of pain catastrophisation (P

Abstract Background The management of shoulder pain is challenging for primary care clinicians considering that 40% of affected individuals remain symptomatic one year after initial consultation. Developing tailored knowledge mobilization interventions founded on evidence-based recommendations while also considering patients’ expectations could improve primary care for shoulder pain. The aim of this qualitative study is to explore patients’ expectations and experiences of their primary care consultation for shoulder pain. Methods In this qualitative study, participants with shoulder pain and having consulted a primary care clinician in the past year were interviewed. All the semi-structured interviews were transcribed verbatim, and inductive thematic analysis was performed to identify themes related to the participants’ expectations and experiences of primary care consultations for shoulder pain. Results Thirteen participants with shoulder pain were interviewed (8 women, 5 men; mean age 50 ± 12 years). Eleven of them initially consulted a family physician or an emergency physician, and two participants initially consulted a physiotherapist. Four overarching themes related to patients’ expectations and experiences were identified from our thematic analysis: 1) I can’t sleep because of my shoulder; 2) I need to know what is happening with my shoulder; 3) But… we need to really see what is going on to help me!; and 4) Please take some time with me so I can understand what to do!. Several participants waited until they experienced a high level of shoulder pain before making an appointment since they were not confident about what their family physician could do to manage their condition. Although some participants felt that their physician took the time to listen to their concerns, many were dissatisfied with the limited assessment and education provided by the clinician. Conclusions Implementing evidence-based recommendations while considering patients’ expectations is important as it may improve patients’ satisfaction with healthcare. Several participants reported that their expectations were not met, especially when it came to the explanations provided. One unexpected finding that emerged from this study was the waiting period between the onset of shoulder pain and when patients decided to consult their primary care clinician.

Background: While low back pain (LBP) is the leading cause of disability worldwide, its clinical objective assessment is currently limited. Part of this syndrome arises from the abnormal sensorimotor control of back muscles, involving increased muscle fatigability (i.e., assessed with the Biering–Sorensen test) and abnormal muscle activation patterns (i.e., the flexion–extension test). Surface electromyography (sEMG) provides objective measures of muscle fatigue development (median frequency drop, MDF) and activation patterns (RMS amplitude change). This study therefore assessed the sensitivity and validity of a novel and flexible sEMG system (NSS) based on PEVA electrodes and potentially embeddable in textiles, as a tool for objective clinical LBP assessment. Methods: Twelve participants wearing NSS and a commercial laboratory sEMG system (CSS) performed two clinical tests used in LBP assessment (Biering–Sorensen and flexion–extension). Erector spinae muscle activity was recorded at T12-L1 and L4-L5. Results: NSS showed sensitivity to sEMG changes associated with fatigue development and muscle activations during flexion–extension movements (p < 0.05) that were similar to CSS (p > 0.05). Raw signals showed moderate cross-correlations (MDF: 0.60–0.68; RMS: 0.53–0.62). Adding conductive gel to the PEVA electrodes did not influence sEMG signal interpretation (p > 0.05). Conclusions: This novel sEMG system is promising for assessing electrophysiological indicators of LBP during clinical tests.

BackgroundFatigue impacts motor performance and upper limb kinematics. It is of interest to study whether it is possible to minimize the potentially detrimental effects of fatigue with prevention programs.ObjectiveTo determine the effect of task-specific training on upper limb kinematics and motor performance when reaching in a fatigued state.MethodsThirty healthy participants were recruited (Training group n = 15; Control group n = 15). Both groups took part in two evaluation sessions (Day 1 and Day 5) during which they performed a reaching task (as quickly and accurately as possible) in two conditions (rested and fatigued). During the reaching task, joint kinematics and motor performance (accuracy and speed) were evaluated. The Training group participated in three task-specific training sessions between Day 1 and Day 5; they trained once a day, for three days. The Control group did not perform any training. A three-way non-parametric ANOVA for repeated measures (Nonparametric Analysis of Longitudinal Data; NparLD) was used to assess the impact of the training (Condition [within subject]: rested, fatigued; Day [within subject]: Day 1 vs. Day 5 and Group [between subjects]: Training vs. Control).ResultsAfter the training period, the Training group significantly improved their reaching speed compared to the Control group (Day x Group p < .01; Time effect: Training group = p < .01, Control group p = .20). No between-group difference was observed with respect to accuracy. The Training group showed a reduction in contralateral trunk rotation and lateral trunk flexion in Day 2 under the fatigue condition (Group x Day p < .04; Time effect: Training group = p < .01, Control group = p < .59).ConclusionAfter the 3-day training, participants demonstrated improved speed and reduced reliance on trunk compensations to complete the task under fatigue conditions. Task-specific training could help minimizing some effects of fatigue.

With the overall objective of providing implication for clinical and research practices regarding the identification and measurement of modifiable predicting factors for return to work (RTW) in people with musculoskeletal disorders (MSDs) and common mental disorders (CMDs), this study 1) systematically examined and synthetized the research evidence available in the literature on the topic, and 2) critically evaluated the tools used to measure each identified factor. A systematic search of prognostic studies was conducted, considering four groups of keywords: 1) population (i.e., MSDs or CMDs), 2) study design (prospective), 3) modifiable factors, 4) outcomes of interest (i.e., RTW). Studies showing high risk of bias were eliminated. Tools used to measure prognostic factors were assessed using psychometric and usability criteria. From the 78 studies that met inclusion criteria, 19 (for MSDs) and 5 (for CMDs) factors reaching moderate or strong evidence were extracted. These factors included work accommodations, RTW expectations, job demands (physical), job demands (psychological), job strain, work ability, RTW self-efficacy, expectations of recovery, locus of control, referred pain (back pain), activities as assessed with disability questionnaires, pain catastrophizing, coping strategies, fears, illness behaviours, mental vitality, a positive health change, sleep quality, and participation. Measurement tools ranged from single-item tools to multi-item standardized questionnaires or subscales. The former generally showed low psychometric properties but excellent usability, whereas the later showed good to excellent psychometric properties and variable usability. The rigorous approach to the selection of eligible studies allowed the identification of a relatively small set of prognostic factors, but with a higher level of certainty. For each factor, the present tool assessment allows an informed choice to balance psychometric and usability criteria.

Abstract Background Shoulder pain is difficult to diagnose and treat with half of those affected still symptomatic six months after initial consultation. This may be explained by primary care management not conforming to evidence-based practice. This survey evaluated physiotherapists (PTs) and family physicians' (FPs) knowledge and appropriateness of care in shoulder pain management. Methods A survey sent to PTs and FPs in the province of Quebec, Canada presented four clinical vignettes with cases of rotator cuff (RC) tendinopathy, acute full-thickness RC tear, adhesive capsulitis and traumatic anterior glenohumeral instability. Respondents indicated diagnosis, indications for imaging, specialists’ referrals, and choice of treatments. Answers were compared to recommendations from clinical practice guidelines (CPGs). Participants’ responses were compared between types of providers with Fisher’s exact test. Results Respondents (PTs = 175, FPs = 76) were mostly women with less than ten years of experience. More than 80% of PTs and 84% of FPs correctly diagnosed cases presented. Despite this practice not being recommended, more FPs than PTs recommended an imaging test in the initial management of RC tendinopathy (30% compared to 13%, p = 0.001) and adhesive capsulitis (51% compared to 22%, p = 0.02). For full-thickness RC tear and shoulder instability, up to 72% of FPs and 67% of PTs did not refer to a specialist for a surgical opinion, although recommended by CPGs. For RC tendinopathy, 26% of FPs and 2% of PTs (p

Le développement des environnements numériques d’apprentissage (ENA), en plus de permettre un accès plus facile au savoir pour tous, présente un nouvel éventail de possibilités pédagogiques. Les infrastructures de données intrinsèquement liées aux technologies du Web favorisent l’apprentissage adaptatif et la personnalisation des parcours. C’est le cas de la plateforme en ligne Gérer ma douleur, qui propose un ensemble de ressources pour les personnes souffrant de douleurs chroniques afin de les aider à mieux les gérer. Dans le cadre du développement de cette plateforme, l’équipe de recherche-développement a procédé à l’étude de l’usage de ces infrastructures de données, pour proposer de nouvelles offres et fonctionnalités de façon à soutenir les parcours d’apprentissage. Un module de suivi de parcours d’apprentissage a été développé en partenariat avec de potentiels futurs utilisateurs, en suivant une méthodologie de prototypage rapide. De plus, un système de collecte et d’observation des données d’interactions des utilisateurs avec la plateforme a été mis en place en utilisant la norme xAPI, dans l’optique d’améliorer le fonctionnement du dispositif d’apprentissage et les différentes ressources éducatives.

Abstract Background Individuals living with a rheumatic pain condition can face delays in accessing pain clinics, which prevents them from receiving timely treatment. Little is known regarding their specific healthcare utilization in order to alleviate pain while waiting to obtain services in pain clinics. Hence, the aim of this study was to explore the perceptions and experiences of persons living with rheumatic conditions regarding healthcare utilization while waiting to access a pain clinic. Methods In this qualitative descriptive study, semi-structured interviews were conducted with adults living with a painful rheumatic condition that reported either being waiting for admission in a pain clinic, having been referred but then denied pain clinic services, or having received services during the previous six months, in the province of Quebec, Canada. The interviews were transcribed verbatim, and an inductive thematic analysis was performed. Results Twenty-six individuals were interviewed (22 women and 4 men; mean age 54 ± 10 years). Three themes were identified: 1) lacking guidance in identifying solutions to their complex and multidimensional needs, 2) struggling to obtain and maintain services due to systemic access barriers, and 3) displaying resilience through a search for accessible and sustainable self-management strategies. Conclusions The current approaches and structures of health services fail to adequately answer the service needs of individuals experiencing painful rheumatic conditions. Important shifts are required in pain education, in increasing access to multidisciplinary approaches at the primary care level and in breaking down barriers individuals with chronic pain face to receive appropriate and timely care.

IntroductionTrunk muscle endurance (TME) tests are commonly used by clinicians to assess muscle performance changes in response to rehabilitation in patients with low back pain (LBP). The aim of this study was to assess the responsiveness of three TME-tests in patients with LBP and to evaluate the relationships between changes in TME and improvement in self-reported function.Materials and MethodsEighty-four LBP patients were evaluated at baseline and after completion of a 6-week training program. Function was assessed with the modified Oswestry Disability Index (ODI) while TME was estimated using three tests: (1) the Biering-Sørensen, (2) the side bridge endurance tests (both sides), and (3) the trunk flexor endurance test. The standardized response mean (SRM) and the minimal clinical important difference (MCID) for each TME-test, and the relationships between changes in TME and improvement in ODI were calculated.ResultsSRMs were small to large for TME-tests (range: 0.43–0.82), and large for the ODI (2.85) and no clinically useful MCID was identified for the TME-tests (area under the curve below 0.70). No significant correlations were found between changes in the TME and change in ODI scores (r 0.05).ConclusionOur results show a weak responsiveness of TME-tests in patients with LBP. There was no association between endurance performance change and self-reported functional change. TME-tests may not be a key component of rehabilitation monitoring in patients with LBP.

Introduction Approximately 33% of people who contracted COVID-19 still experience symptoms 12 weeks after infection onset. This persistence of symptoms is now considered a syndrome itself called ‘long COVID’. Evidence regarding long COVID and its cognitive and physical impacts is growing, but the literature is currently lacking objectively measured data to guide towards adapted healthcare trajectories. The objectives are to describe the physical and cognitive impairments experienced by individuals living with long COVID using self-reported and clinical objective measures, and to compare the evolution over time of the physical and cognitive state between adults living with long COVID (at least one physical or cognitive COVID-19 symptom for more than 12 weeks following infection; long COVID group), people who developed COVID-19 but did not experience persistent symptoms (short COVID group) and people who did not develop COVID-19 (control group).Methods and analysis In this longitudinal cohort study, 120 participants will be recruited in each group. Variables will be collected through three evaluation sessions over 6 months (baseline, 3 months, 6 months). Variables include self-administered questionnaires on health-related quality of life, comorbidity, sleep, pain, anxiety, depressive symptoms, fatigue and cognitive function, as well as objective measures of cognitive (attention, memory, executive functioning) and physical (grip strength, balance, gait speed, gait endurance, VO2, frailty) functions. Activity, heart rate and sleep will be monitored with a fitness tracker watch for 7 days following evaluation sessions. Maximum-likelihood analyses of variance (ANOVAs) will be used to compare data at baseline between groups. Repeated measures ANOVAs will be used to compare the longitudinal performance variations across groups of the self-reported and clinical variables.Ethics and dissemination Ethics committees of the CIUSSS de la Capitale-Nationale and CIUSSS de l’Est-de-l’Île-de-Montréal approved the project. Results will be disseminated through clinical and community platforms as well as through peer-reviewed manuscripts and international conferences.Trial registration number NCT05216536.

Abstract Background Scapular stabilization exercises (SSE) are often included in the treatment of individuals with rotator cuff-related shoulder pain (RCRSP) to decrease pain and improve function. These SSE typically aim to strengthen the scapular muscles and optimize dynamic neuromuscular control of the scapula, which may improve overall shoulder stability and movement quality. No consensus of the recommended SSE for the management of RCRSP is available. Hence, this study aimed to consult physiotherapists to co-create an inventory of recommended SSE based on the exercise’s relevance and frequency of prescriptions for the rehabilitation of individuals with RCRSP. Methods A group of 16 physiotherapists with experience in treating shoulder pain participated in a sequential consultation incorporating two distinct rounds of consultation focusing on SSE (modified Delphi design). In round 1, physiotherapists identified and demonstrated up to 10 SSE that they commonly recommend or use among individuals with RCRSP. The description and performance of all SSE were audio and video recorded. All SSE suggested by more than one participant in round 1 advanced to round 2. In round 2, physiotherapists rated these SSE on a 4-point Likert scale according to their perceived relevance and frequency of prescription for this population. Results In round 1, out of the 25 SSE recommended by participants, 19 SSE (76.0%) were recommended by more than one physiotherapist and advanced to round 2. In round 2, 13 SSE were consensually classified (agreement ≥75%) as being relevant for the rehabilitation of individuals with RCRSP. SSE targeting the recruitment of the serratus anterior and lower trapezius muscles were considered the most relevant for the management of RCRSP, whereas SSE targeting neuromuscular scapular control were the most prescribed SSE for the management of RCRSP. Conclusions An inventory composed of 13 SSE was co-created by physiotherapists based on their relevance and frequency of prescription for the rehabilitation of individuals with RCRSP. When designing an exercise program, physiotherapists can use this SSE inventory to inform their exercise selection, in combination with their current knowledge on shoulder rehabilitation, as well as patients’ preferences.

Abstract Background Experimental pain during gait has been shown to interfere with learning a new locomotor task. However, very few studies have investigated the impact of clinical pain on motor learning due to the challenges associated with clinical populations. Objective The first objective of this proof-of-concept study was to determine the feasibility to obtain two groups of participants with chronic ankle pathology with or without residual pain while walking. The second objective was to evaluate the impact of clinical musculoskeletal pain on motor learning during gait. Methods Participants with chronic isolated ankle pathology were recruited and their personal and clinical characteristics were collected (functional performance, dorsiflexion maximal strength, range of motion). To assess motor acquisition (Day 1) and retention (Day 2), participants performed an adaptation task on two consecutive days that consisted of walking while experiencing a perturbing force applied to the ankle. The level of pain during the task was measured, and participants who reported pain were attributed to the Pain group and participants without pain to the No Pain group. Learning performance was assessed by measuring ankle kinematics (Mean plantarflexion absolute error) and learning strategy was assessed by measuring the Relative timing of error and the tibialis anterior (TA) electromyographic activity. Results Twenty-five participants took part in the experiment. Eight (32%) were excluded because they could not be included in either the Pain or No Pain group due to the intermittent pain, leaving eight participants in the Pain group and nine in the No Pain group. Both groups were similar in terms of baseline characteristics. Musculoskeletal pain had no influence on learning performance, but the learning strategy were different between the two groups. The No Pain group showed a TA activity reduction before perturbation between the days, while the Pain group did not. Conclusion Some barriers were identified in studying musculoskeletal pain including the high rates of participants’ exclusion, leading to a small sample size. However, we showed that it is feasible to investigate clinical pain and motor learning. From the results of this study, musculoskeletal pain has no influence on motor learning performance but influences the learning strategy.

IntroductionFollowing most musculoskeletal injuries, motor control is often altered. Acute pain has been identified as a potential contributing factor. However, there is little evidence of this interaction for acute pain following ankle sprains. As pain is generally present following this type of injury, it would be important to study the impact of acute pain on ankle motor control. To do so, a valid and reliable motor control test frequently used in clinical settings should be used. Therefore, the objective of this study was therefore to assess the effect of acute ankle pain on the modified Star Excursion Balance Test reach distance.MethodsUsing a cross-sectional design, 48 healthy participants completed the modified Star Excursion Balance Test twice (mSEBT1 and mSEBT2). Following the first assessment, they were randomly assigned to one of three experimental groups: Control (no stimulation), Painless (non-nociceptive stimulation) and Painful (nociceptive stimulation). Electrodes were placed on the right lateral malleolus to deliver an electrical stimulation during the second assessment for the Painful and Painless groups. A generalized estimating equations model was used to compare the reach distance between the groups/conditions and assessments.ResultsPost-hoc test results: anterior (7.06 ± 1.54%; p

Gait modifications are commonly advocated to decrease knee forces and pain in runners with patellofemoral pain (PFP). However, it remains unknown if clinicians can expect immediate effects on symptoms. Our objectives were (1) to compare the immediate effects of gait modifications on pain and kinetics of runners with PFP; (2) to compare kinetic changes in responders and non-responders; and (3) to compare the effects between rearfoot strikers (RFS) and non-RFS. Sixty-eight runners with PFP (42 women, 26 men) ran normally on a treadmill before testing six modifications: 1- increase step rate by 10%; 2- 180 steps per minute; 3- decrease step rate by 10%; 4- forefoot striking; 5- heel striking; 6- running softer. Overall, there were more responders (pain decreased ≥1/10 compared with normal gait) during forefoot striking and increasing step rate by 10% (both 35%). Responders showed greater reductions in peak patellofemoral joint force than non-responders during all conditions except heel striking. When compared with non-RFS, RFS reduced peak patellofemoral joint force in a significant manner (P

The study aimed to investigate the effects of footwear on the electromyographic (EMG) activity of pelvic floor muscles (PFMs) and internal oblique (IO) muscles during running at different speeds. The study also aimed to explore the correlation between EMG activity of PFMs and IO muscles and participants’ morphological characteristics. Ten nulliparous female runners were included in the study. The participants ran for 90 s at speeds of 9, 11, and 13 km/h wearing both traditional and minimalist shoes. EMG outcomes were presented as a percentage of maximum voluntary contraction (%MVC). Comparative analysis was conducted using the Wilcoxon rank test. Correlational analysis was performed using the Rho–Spearman correlation coefficient. The %MVC for the IO muscles was significantly lower when using minimalist shoes compared to traditional shoes (p = 0.04). No statistically significant differences were found for the PFMs (p > 0.05). The study also observed large correlations between age and %MVC of the PFMs and IO muscles (rho = −0.64; p = 0.04). Minimalist shoes decreased the activity of IO muscles in female runners. However, no significant differences in EMG activity of PFMs were found when comparing traditional and minimalist footwear. The long-term effects of minimalist footwear on EMG activity of PFMs and IO muscles, as well as their relationship to morphological characteristics, require further investigation.

Electromyography (EMG) is gaining importance in many research and clinical applications, including muscle fatigue detection, control of robotic mechanisms and prostheses, clinical diagnosis of neuromuscular diseases and quantification of force. However, EMG signals can be contaminated by various types of noise, interference and artifacts, leading to potential data misinterpretation. Even assuming best practices, the acquired signal may still contain contaminants. The aim of this paper is to review methods employed to reduce the contamination of single channel EMG signals. Specifically, we focus on methods which enable a full reconstruction of the EMG signal without loss of information. This includes subtraction methods used in the time domain, denoising methods performed after the signal decomposition and hybrid approaches that combine multiple methods. Finally, this paper provides a discussion on the suitability of the individual methods based on the type of contaminant(s) present in the signal and the specific requirements of the application.

Abstract Background Extensive waiting times before receiving services is a major barrier to adequate pain management. Waiting times may have a detrimental impact on patients’ conditions and quality of life. However, there remains a lack of knowledge on the actual experiences of patients waiting to receive services, especially for those with rheumatic conditions. The present study aimed to gain an in-depth understanding of perceptions and experiences of patients with rheumatic conditions regarding access to pain clinic services. The secondary objective was to identify possible solutions to improve this access according to patients’ perspectives. Methods This qualitative study based on semi-structured interviews was conducted with adults with rheumatic conditions waiting to access pain clinics in the province of Quebec, Canada. Interviews were transcribed verbatim and analyzed using thematic content analysis. Results Twenty-six participants were interviewed (22 women and 4 men; mean age 54 ± 10 years). Four main themes were identified: 1) the perception that waiting time is unacceptably long; 2) how the lack of information affects patients’ experiences of waiting; 3) patients’ various expectations towards the pain clinic, from high hopes to disillusionment and 4) carrying an emotional, physical and financial burden resulting from the wait. Participants reported several solutions to improve the experience of waiting, including providing information to patients, increasing resources, improving prioritization processes and care coordination, and providing alternative interventions to patients during the wait. Conclusions For patients with rheumatic conditions, access to pain clinic services is challenging due to extensive waiting times. The burden it imposes on them adds to the existing challenge of living with a chronic rheumatic condition. The solutions identified by participants could serve as building blocks to develop and implement measures to improve patients’ experience of accessing pain-related services.

Abstract Study design Single-blind parallel group randomized clinical trial. Objectives To compare the effects of neurocryostimulation (NCS) with those of traditional ice application on functional recovery, pain, edema and ankle dorsiflexion range of motion (ROM) in individuals receiving physiotherapy treatments for acute lateral ankle sprains (LAS). Background Ankle sprain is a very common injury and its management is often costly, with important short- and long-term impacts on individuals and society. As new methods of therapy using cold (cryotherapy) are emerging for the treatment of musculoskeletal conditions, little evidence exists to support their use. NCS, which provokes a rapid cooling of the skin with the liberation of pressured CO2, is a method believed to accelerate the resorption of edema and recovery in the case of traumatic injuries. Methods Forty-one participants with acute LAS were randomly assigned either to a group that received in-clinic physiotherapy treatments and NCS (experimental NCS group, n = 20), or to a group that received the same in-clinic physiotherapy treatments and traditional ice application (comparison ice group, n = 21). Primary (Lower Extremity Functional Scale - LEFS) and secondary (visual analog scale for pain intensity at rest and during usual activities in the last 48 h, Figure of Eight measurement of edema, and weight bearing lunge for ankle dorsiflexion range of motion) outcomes were evaluated at baseline (T0), after one week (T1), two weeks (T2), four weeks (T4) and finally, after six weeks (T6). The effects of interventions were assessed using two-way ANOVA-type Nonparametric Analysis for Longitudinal Data (nparLD). Results No significant group-time interaction or group effect was observed for all outcomes (0.995 ≥ p ≥ 0.057) following the intervention. Large time effects were however observed for all outcomes (p

Abstract Background Low back pain (LBP) is the first cause of years lived with disability worldwide. This is due to the development of chronic pain. Thus, it is necessary to identify the best therapeutic approaches in the acute phase of LBP to limit the transition to chronic pain. Superficial heat presents the highest level of evidence for short-term reduction in pain and disability in acute LBP. Physical activity is also recommended to avoid transition to chronic LBP, but there is a lack of evidence to determine its effect to reduce acute LBP. Also, the long-term effects of these interventions are unknown. This is a protocol for a randomized controlled trial (RCT) to determine the short and long-term effects of wearable continuous low-level thermal therapy, in combination with exercises or not, on disability and pain. Methods/design Sixty-nine participants with acute LBP will be randomly assigned to one of three intervention programs: 1) thermal therapy, 2) thermal therapy + exercises, and 3) control. The interventions will be applied for 7 continuous days. The primary outcome will be disability and secondary outcomes will be pain intensity, pain-related fear, self-efficacy, number of steps walked and perception of change. The evaluators will be blinded to the interventions, and participants will be blinded to other groups’ interventions. Primary and secondary outcomes will be compared between intervention groups. Discussion This study will provide new evidence about acute LBP treatments, to limit transition to chronicity. This will be the first study to measure the long-term effects of wearable continuous low-level thermal therapy, combined or not to exercises. Trial registration This RCT has been retrospectively registered on ClinicalTrials.gov ( NCT03986047 ) on June 14th, 2019.

Abstract. Introduction:. Numerous definitions of acute low back pain (aLBP) exist. The use of different definitions results in variability in reported prevalence or incidence, conflicting data regarding factors associated with the transition to chronic LBP (cLBP), and hampers comparability among studies. Objective:. Here, we compare the impact of 3 aLBP definitions on the number of aLBP cases and participants' characteristics and explore the distribution of participants across definitions. Methods:. A sample of 1264 participants from the Quebec Low Back Pain Study was included. Three definitions of aLBP were used: (1) not meeting the National Institutes of Health (NIH) cLBP definition (“nonchronic”), (2) pain beginning 5 years of pain than in the other definitions. Half the participants meeting the “acute” definition and one-third of participants meeting the “new episode” definition were also classified as cLBP based on the NIH definition. Conclusions:. Our results highlight the importance of the definition used for aLBP. Different definitions influence the sample size and clinical profiles (group's characteristics). We recommended that cohort studies examining the transition from aLBP to cLBP ensure that the definitions selected are mutually exclusive (ie, participants included [aLBP] differ from the expected outcome [cLBP]).

Abstract Background Access to multidisciplinary pain treatment facilities (MPTF) is limited by extensive waiting time in many countries. However, there is a lack of knowledge about the impact of waiting time on clinical outcomes, particularly for patients with rheumatic conditions. This study examined the association between waiting time for MPTF and clinical outcomes in patients with rheumatic conditions. Methods Data were extracted from the Quebec Pain Registry, a large database of patients who received services in MPTF. The associations between waiting time (classified as 6 months) and change in pain interference, pain intensity and health-related quality of life, from the initial visit at the MPTF to the 6-month follow-up, were tested using generalized estimating equations. Results A total of 3230 patients with rheumatic conditions (mean age: 55.8 ± 14.0 years; 66% were women) were included in the analysis. Small significant differences in improvement between waiting time groups were revealed, with patients waiting less than 2 months having a larger improvement in all clinical outcomes compared to patients who waited 2–6 months or over 6 months before their initial visit (adjusted time X group effect p ≤ 0.001). Only patients waiting less than 2 months reached a clinically important improvement in pain interference (1.12/10), pain intensity (1.3/10) and physical and mental quality of life (3.9 and 3.7/100). Conclusions Longer delays experienced by patients before receiving services in MPTF were associated with statistically significant smaller improvements in pain interference, pain intensity and health-related quality of life; these differences were, however, not clinically significant. Based on these results, we advise that strategies are developed not only to reduce waiting times and mitigate their impacts on patients with rheumatic conditions, but also to improve treatment effectiveness in MPTF.

Objective Human gait requires complex somatosensory processing of various inputs such as proprioception. Proprioception can be altered in the presence of pain. This has been shown mostly during controlled tasks, thereby limiting the influence of external perturbations. While controlling the environment is sometimes warranted, it limits the ecological validity of the data. Using robotic orthoses to apply perturbations during movements seems a promising tool to functionally assess proprioception, where the complex somatosensory processing required in real-life situations is at play. The main objective of this study was to compare the proprioceptive threshold of healthy participants during gait in the presence and absence of an acute experimental pain. Methods 36 healthy participants walked on a treadmill while wearing a robotized ankle–foot orthosis (rAFO) around their right ankle. The rAFO applied torque perturbations of graded magnitudes during the swing phase of gait. Participants had to report the presence/absence of such perturbations, as a measure of proprioceptive threshold. Following initial assessment, they were randomly assigned to one of three experimental groups: Control (no stimulation), Painless (non-nociceptive stimulation) and Painful (nociceptive stimulation). Electrodes placed on the right lateral malleolus delivered an electrical stimulation during the second assessment for Painless and Painful groups. A Kruskal-Wallis was used to compare the percentage of change of the three groups between the two assessments. Results A 31.80±32.94% increase in proprioceptive threshold, representing an increase of 1.3±1.2 Nm in the detection threshold, was observed for the Painful group only (pConclusion Findings show that the presence of pain at the ankle can alter participants’ proprioceptive threshold during gait. Clinical assessment of proprioception should therefore carefully consider the presence of pain when evaluating a patient’s performance using clinical proprioceptive test and consider the negative effect of pain on proprioceptive threshold for test interpretation.

BackgroundAltered movement patterns have been proposed as an etiological factor for the development of musculoskeletal pain. Fatigue influences upper limb kinematics and movement performance which could extend to the contralateral limb and potentially increasing risk of injury. The aim of this study was to investigate the impact of fatigue at the dominant arm on the contralateral upper limb movement.MethodsForty participants were randomly assigned to one of two groups: Control or Fatigue Group. All participants completed a reaching task at the baseline and post-experimental phase, during which they reached four targets with their non-dominant arm in a virtual reality environment. Following the baseline phase, the Fatigue Group completed a shoulder fatigue protocol with their dominant arm only, while the Control Group took a 10-minute break. Thereafter, the reaching task was repeated. Upper limb and trunk kinematics (joint angles and excursions), spatiotemporal (speed and accuracy) and surface electromyographic (sEMG) activity (sEMG signal mean epoch amplitude and median frequency of the EMG power spectrum) were collected. Two-way repeated-measures ANOVA were performed to determine the effects of Time, Group and of the interaction between these factors.ResultsThere was a significant Time x Group interaction for sternoclavicular elevation range of motion (p = 0.040), movement speed (p = 0.043) and accuracy (p = 0.033). The Fatigue group showed higher contralateral sternoclavicular elevation and increased movement error while experiencing fatigue in the dominant arm. Moreover, the Control group increased their speed during the Post-experimental phase compared to baseline (p = 0.043), while the Fatigue group did not show any speed improvement. There was no EMG sign of fatigue in any of the muscles evaluated.ConclusionThis study showed that fatigue at the dominant shoulder impacts movement at the contralateral upper limb. Such changes may be a risk factor for the development of shoulder pain in both the fatigued and non-fatigued limbs.

Work-related upper extremity disorders are costly to society due to resulting medical costs, presenteeism and absenteeism. Although their aetiology is likely multifactorial, physical workplace factors are known to play an important role in their development. Promising options for preventing work-related upper extremity disorders include assistive technologies such as dynamic arm supports designed to follow the movement of the arm while compensating for its weight. The objective of this study was to assess the effects of a dynamic arm support on perceived exertion, muscle activity and movement patterns of the upper limb during repetitive manual tasks in healthy individuals. Thirty healthy right-handed individuals were allocated either a static or a dynamic task to perform with and without a dynamic arm support. During the task, surface electromyographic activity (anterior and middle deltoid, upper trapezius) and upper limb kinematics (elbow, shoulder, sternoclavicular) were measured using surface EMG and inertial sensors. Results showed that the dynamic arm support significantly reduced perceived exertion during the tasks and limited the development of muscular fatigue of the anterior and middle deltoid as demonstrated by EMG signal mean epoch amplitudes and median frequency of the EMG power spectrum. The dynamic arm support also prevented a decrease in shoulder elevation and an increase in total shoulder joint excursion during static and dynamic task, respectively. These results denote the potential benefits of dynamic arm supports in work environments. Further studies should focus on their efficacy, acceptability and implementability in work settings.

Introduction: Lower limb pain, whether induced experimentally or as a result of a musculoskeletal injury, can impair motor control, leading to gait adaptations such as increased muscle stiffness or modified load distribution around joints. These adaptations may initially reduce pain but can also lead to longer-term maladaptive plasticity and to the development of chronic pain. In humans, many current experimental musculoskeletal-like pain models are invasive, and most don’t accurately reproduce the movement-related characteristics of musculoskeletal pain. The main objective of this study was to measure pain adaptation strategies during gait of a musculoskeletal-like experimental pain protocol induced by phase-specific, non-invasive electrical stimulation.Methods: Sixteen healthy participants walked on a treadmill at 4 km/h for three consecutive periods (BASELINE, PAIN, and POST-PAIN). Painful electrical stimulations were delivered at heel strike for the duration of heel contact (HC) using electrodes placed around the right lateral malleolus to mimic ankle sprains. Gait adaptations were quantified bilaterally using instrumented pressure-sensitive insoles. One-way ANOVAs and group time course analyses were performed to characterize the impact of electrical stimulation on heel and forefoot contact pressure and contact duration.Results: During the first few painful strides, peak HC pressure decreased on the painful side (8.6 ± 1.0%, p < 0.0001) and increased on the non-stimulated side (11.9 ± 0.9%, p < 0.0001) while HC duration was significantly reduced bilaterally (painful: 12.1 ± 0.9%, p < 0.0001; non-stimulated: 4.8 ± 0.8%, p < 0.0001). No clinically meaningful modifications were observed for the forefoot. One minute after the onset of painful stimulation, perceived pain levels stabilized and peak HC pressure remained significantly decreased on the painful side, while the other gait adaptations returned to pre-stimulation values.Discussion: These results demonstrate that a non-invasive, phase-specific pain can produce a stable painful gait pattern. Therefore, this protocol will be useful to study musculoskeletal pain locomotor adaptation strategies under controlled conditions.

Abstract. A higher level of pain self-efficacy has been suggested as a predictor of a better outcome in patients with musculoskeletal disorders. The Pain Self-Efficacy Questionnaire (PSEQ) is one of the most frequently used patient-reported outcome measures for pain self-efficacy. The purpose of this study was to conduct a systematic review that would identify, appraise, and synthetize the psychometric properties of the PSEQ. Embase, MEDLINE, and CINAHL databases were searched for publications reporting on psychometric properties of the PSEQ in populations with musculoskeletal disorders. After applying selection criteria on identified citations, 28 studies (9853 participants) were included. The methodological quality as measured with the COSMIN risk of bias tool varied from adequate to very good for most measurement properties. The results showed a weighted mean intraclass correlation coefficient of 0.86 (range: 0.75–0.93) for test–retest reliability for the original 10-item PSEQ and the minimal detectable change at 95% confidence interval was 11.52 out of 60 points. Effect size and standardized response mean values were 0.53 and 0.63, respectively, whereas the minimal clinically important difference ranged from 5.5 to 8.5 in patients with chronic low back pain. Internal consistency (Cronbach alpha) ranged from 0.79 to 0.95. The results also showed that the PSEQ has low to moderate correlations with measures of quality of life, disability, pain, pain interference, anxiety, depression, and catastrophizing. Finally, the PSEQ has been adapted and validated in 14 languages. Overall, the results demonstrate that the PSEQ has excellent validity, reliability, and responsiveness. Further high-quality studies are needed to determine responsiveness in populations other than chronic low back pain.

Abstract Background People with chronic shoulder pain have been shown to present with motor adaptations during arm movements. These adaptations may create abnormal physical stress on shoulder tendons and muscles. However, how and why these adaptations develop from the acute stage of pain is still not well‐understood. Objective To investigate motor adaptations following acute experimental shoulder pain during upper limb reaching. Methods Forty participants were assigned to the Control or Pain group. They completed a task consisting of reaching targets in a virtual reality environment at three time points: (1) baseline (both groups pain‐free), (2) experimental phase (Pain group experiencing acute shoulder pain induced by injecting hypertonic saline into subacromial space), and (3) Post experimental phase (both groups pain‐free). Electromyographic (EMG) activity, kinematics, and performance data were collected. Results The Pain group showed altered movement planning and execution as shown by a significant increased delay to reach muscles EMG peak and a loss of accuracy, compared to controls that have decreased their mean delay to reach muscles peak and improved their movement speed through the phases. The Pain group also showed protective kinematic adaptations using less shoulder elevation and elbow flexion, which persisted when they no longer felt the experimental pain. Conclusion Acute experimental pain altered movement planning and execution, which affected task performance. Kinematic data also suggest that such adaptations may persist over time, which could explain those observed in chronic pain populations.

Abstract Background Mild traumatic brain injury (mTBI) is an acknowledged public health problem. Up to 25% of adult with mTBI present persistent symptoms. Headache, dizziness, nausea and neck pain are the most commonly reported symptoms and are frequently associated with cervical spine and vestibular impairments. The most recent international consensus statement (2017 Berlin consensus) recommends the addition of an individualized rehabilitation approach for mTBI with persistent symptoms. The addition of an individualized rehabilitation approach including the evaluation and treatment of cervical and vestibular impairments leading to symptoms such as neck pain, headache and dizziness is, however, recommended based only on limited scientific evidence. The benefit of such intervention should therefore be further investigated. Objective To compare the addition of a 6-week individualized cervicovestibular rehabilitation program to a conventional approach of gradual sub-threshold physical activation (SPA) alone in adults with persistent headache, neck pain and/or dizziness-related following a mTBI on the severity of symptoms and on other indicators of clinical recovery. We hypothesize that such a program will improve all outcomes faster than a conventional approach (between-group differences at 6-week and 12-week). Methods In this single-blind, parallel-group randomized controlled trial, 46 adults with subacute (3 to12 weeks post-injury) persistent mTBI symptoms will be randomly assigned to: 1) a 6-week SPA program or 2) SPA combined with a cervicovestibular rehabilitation program. The cervicovestibular rehabilitation program will include education, cervical spine manual therapy and exercises, vestibular rehabilitation and home exercises. All participants will take part in 4 evaluation sessions (baseline, week 6, 12 and 26) performed by a blinded evaluator. The primary outcome will be the Post-Concussion Symptoms Scale. The secondary outcomes will be time to clearance to return to function, number of recurrent episodes, Global Rating of Change, Numerical Pain Rating Scale, Neck Disability Index, Headache Disability Inventory and Dizziness Handicap Inventory. A 2-way ANOVA and an intention-to-treat analysis will be used. Discussion Controlled trials are needed to determine the best rehabilitation approach for mTBI with persistent symptoms such as neck pain, headache and dizziness. This RCT will be crucial to guide future clinical management recommendations. Trial registration ClinicalTrials.gov Identifier - NCT03677661, Registered on September, 15th 2018.

Introduction While multiple pharmacological and non-pharmacological interventions treating chronic non-specific low back pain (CLBP) are available, they have been shown to produce at best modest effects. Interventions such as repetitive transcranial magnetic stimulation (rTMS), a form of non-invasive brain stimulation, have exhibited promising results to alleviate chronic pain. However, evidence on the effectiveness of rTMS for CLBP is scarce due to limited rigorous clinical trials. Combining rTMS with motor control exercises (MCE) may help to address both central and nociceptive factors contributing to the persistence of LBP. The primary aim of this randomised controlled trial is to compare the effectiveness of a combination of rTMS and MCE to repeated rTMS sessions alone, sham rTMS and a combination of sham rTMS and MCE on pain intensity.Methods and analysis One hundred and forty participants (35/group) with CLBP will be randomised into four groups (active rTMS+MCE, sham rTMS+MCE, active rTMS and sham rTMS) to receive 10 sessions of their allocated intervention. The primary outcome will be the pain intensity, assessed at baseline, 4, 8, 12 and 24 weeks. Secondary outcomes will include disability, fear of movement, quality of life and patient global rating of change.Ethics and dissemination Ethics approval was obtained from the Comité d’éthique de la recherche sectoriel en réadaptation et intégration sociale, CIUSS de la Capitale Nationale in June 2019 (#2020–1844 – CER CIUSSS-CN). The results of the study will be submitted to a peer-reviewed journal and scientific meetings.Trial registration number NCT04555278.

BackgroundEfficient shoulder movement depends on the ability of central nervous system to integrate sensory information and to create an appropriate motor command. Various daily encountered factors can potentially compromise the execution of the command, such as fatigue. This study explored how fatigue influences shoulder movements during upper limb reaching.MethodsForty healthy participants were randomly assigned to one of two groups: Control or Fatigue Group. All participants completed an upper limb reaching task at baseline and post-experimental, during which they reached four targets located at 90° of shoulder abduction, 90° external rotation at 90° abduction, 120° scaption, and 120° flexion in a virtual reality environment. Following the baseline phase, the Fatigue Group completed a shoulder fatigue protocol, while Controls took a 10-minute break. Thereafter, the reaching task was repeated. Upper limb kinematic (joint angles and excursions) and spatiotemporal (speed and accuracy) data were collected during the reaching task. Electromyographic activity of the anterior and middle deltoids were also collected to characterize fatigue. Two-way repeated-measures ANOVA were performed to determine the effects of Time, Group and of the interaction between these factors.ResultsThe Fatigue group showed decreased mean median power frequency and increased electromyographic amplitudes of the anterior deltoid (p < 0.05) following the fatigue protocol. Less glenohumeral elevation, increased trunk flexion and rotation and sternoclavicular elevation were also observed in the Fatigue group (Group x Time interaction, p < 0.05). The Control group improved their movement speed and accuracy in post-experimental phase, while the Fatigue group showed a decrease of movement speed and no accuracy improvement (Group x Time interaction, p < 0.05).ConclusionIn a fatigued state, changes in movement strategy were observed during the reaching task, including increased trunk and sternoclavicular movements and less glenohumeral movement. Performance was altered as shown by the lack of accuracy improvement over time and a decrease in movement speed in the Fatigue group.

Background/Aim Ankle sprains are frequent musculoskeletal injuries that can lead to sensorimotor deficits provoking long-term instability at the ankle joint. A broad variety of clinical tests currently exist to assess sensorimotor processing, and are commonly clinically referred to as proprioceptive tests. However, there is a discrepancy in the use of the term proprioception when looking at the main outcome of these tests. As identifying specific deficits is important for motor recovery, it is critical for clinicians to select the most appropriate tests.Methods A systematic review of four databases was performed to provide an up-to-date review of the psychometric properties of available tests referred to as proprioceptive tests. Seventy-nine articles on eight ankle proprioceptive tests were included and critically appraised. Data on validity, reliability and responsiveness were extracted from the included articles and synthesised. The tests reviewed were then divided into two categories based on their main outcome: motor control or somatosensation.Results Strong evidence showed that the Star Excursion Balance Test, a motor control test, is capable of differentiating between stable and unstable ankles. Moderate evidence suggests that somatosensation tests, such as Joint Position Sense, are also valid and reliable, but their responsiveness has yet to be evaluated.Conclusions Together, these findings indicate that the Star Excursion Balance Test can be used in the clinic to assess motor control based on its excellent psychometric properties. However, as ankle stability control involves complex sensorimotor interactions, care has to be taken regarding the use of this test as a specific tool for proprioception assessment.

Abstract Background Low back pain (LBP) encompasses heterogeneous patients unlikely to respond to a unique treatment. Identifying sub-groups of LBP may help to improve treatment outcomes. This is a hypothesis-setting study designed to create a clinical prediction rule (CPR) that will predict favorable outcomes in soldiers with sub-acute and chronic LBP participating in a multi-station exercise program. Methods Military members with LBP participated in a supervised program comprising 7 stations each consisting of exercises of increasing difficulty. Demographic, impairment and disability data were collected at baseline. The modified Oswestry Disability Index (ODI) was administered at baseline and following the 6-week program. An improvement of 50% in the initial ODI score was considered the reference standard to determine a favorable outcome. Univariate associations with favorable outcome were tested using chi-square or paired t-tests. Variables that showed between-group (favorable/unfavorable) differences were entered into a logistic regression after determining the sampling adequacy. Finally, continuous variables were dichotomized and the sensitivity, specificity and positive and negative likelihood ratios were determined for the model and for each variable. Results A sample of 85 participants was included in analyses. Five variables contributed to prediction of a favorable outcome: no pain in lying down (p = 0.017), no use of antidepressants (p = 0.061), FABQ work score

Objective: To perform a systematic review and meta-analysis of randomized controlled trials on the efficacy of workplace-based interventions to prevent or treat shoulder pain. Data sources: A systematic review of 4 databases was performed up to January 2016. Study selection: Randomized controlled trials were included if the intervention under study was a workplace-based intervention performed to prevent or reduce shoulder pain and disability in workers. Data extraction: The methodological quality of the studies was evaluated and meta-analyses were conducted. Pooled mean differences and risk ratios were calculated. Data synthesis: Data from 4 studies on strengthening exercises performed in the workplace for workers with shoulder pain (n = 368) were pooled. A statistically significant reduction in pain intensity was observed compared with different control interventions (mean differences (scale out of 10) 1.31 (95% confidence interval (95% CI) 0.86–1.76)). Pooled data from 5 studies on the efficacy of workstation modifications (n = 2,148) showed a statistically significant reduction in the prevalence of shoulder pain with a risk ratio of 1.88 (95% CI 1.20–2.96) compared with different control interventions. Conclusion: Low-grade evidence exists that a workplace exercise programme may reduce the intensity of shoulder pain, and that workstation modifications may reduce the prevalence of shoulder pain.

Background Rotator cuff calcific tendinopathy is characterised by the deposition of hydroxyapatite crystals in one of the rotator cuff tendons and can be managed by ultrasound-guided lavage. However, evidence regarding the efficacy of ultrasound-guided lavage for rotator cuff calcific tendinopathy remains inconclusive. The aim of this systematic review and meta-analysis is to update the available evidence on the efficacy of ultrasound-guided lavage in adults with rotator cuff calcific tendinopathy.Methods A literature search was conducted up to April 2018 in four bibliographic databases to identify randomised control trials that compared ultrasound-guided lavage alone with other interventions to treat rotator cuff calcific tendinopathy. Randomised control trials were assessed with the Cochrane Risk of Bias Tool. Meta-analyses and/or qualitative synthesis of the evidence were performed.Results Three randomised control trials were included. Pooled results for pain (n=226) indicated that ultrasound-guided lavage may significantly decrease pain when compared with shockwave therapy, with a mean difference of −1.98 out of 10 points (95% CI −2.52 to −1.45) in the short term and of −1.84 (95% CI −2.63 to −1.04) in the long term. Based on one trial (n=25), ultrasound-guided lavage significantly improved function when compared with shockwave therapy (p

Inertial measurement units have recently shown great potential for the accurate measurement of joint angle movements in replacement of motion capture systems. In the race towards long duration tracking, inertial measurement units increasingly aim to ensure portability and long battery life, allowing improved ecological studies. Their main advantage over laboratory grade equipment is their usability in a wider range of environment for greater ecological value. For accurate and useful measurements, these types of sensors require a robust orientation estimation that remains accurate over long periods of time. To this end, we developed the Allumo software for the preprocessing and calibration of the orientation estimate of triaxial accelerometers. This software has an automatic orientation calibration procedure, an automatic erroneous orientation-estimate detection and useful visualization to help process long and short measurement periods. These automatic procedures are detailed in this paper, and two case studies are presented to showcase the usefulness of the software. The Allumo software is open-source and available online.

Background: Workplace adaptation is the preferred method of intervention to diminish risk factors associated with the development of work-related shoulder disorders. However, the majority of the workplace assessments performed are subjective (e.g., questionnaires). Quantitative assessments are required to support workplace adaptations. The aims of this study are to assess the concurrent validity of inertial measurement units (IMUs; MVN, Xsens) in comparison to a motion capture system (Vicon) during lifting tasks, and establish the discriminative validity of a wireless electromyography (EMG) system for the evaluation of muscle activity. Methods: Sixteen participants performed 12 simple tasks (shoulder flexion, abduction, scaption) and 16 complex lifting tasks (lifting crates of different weights at different heights). A Delsys Trigno EMG system was used to record anterior and middle deltoids’ EMG activity, while the Xsens and Vicon simultaneously recorded shoulder kinematics. Results: For IMUs, correlation coefficients were high (simple task: >0.968; complex task: >0.84) and RMSEs were low (simple task: Conclusions: These results suggest that wireless EMG and IMUs are valid units that can be used to measure physical demand in workplace assessments.

Motion capture systems are recognized as the gold standard for joint angle calculation. However, studies using these systems are restricted to laboratory settings for technical reasons, which may lead to findings that are not representative of real-life context. Recently developed commercial and home-made inertial measurement sensors (M/IMU) are potentially good alternatives to the laboratory-based systems, and recent technology improvements required a synthesis of the current evidence. The aim of this systematic review was to determine the criterion validity and reliability of M/IMU for each body joint and for tasks of different levels of complexity. Five different databases were screened (Pubmed, Cinhal, Embase, Ergonomic abstract, and Compendex). Two evaluators performed independent selection, quality assessment (consensus-based standards for the selection of health measurement instruments [COSMIN] and quality appraisal tools), and data extraction. Forty-two studies were included. Reported validity varied according to task complexity (higher validity for simple tasks) and the joint evaluated (better validity for lower limb joints). More studies on reliability are needed to make stronger conclusions, as the number of studies addressing this psychometric property was limited. M/IMU should be considered as a valid tool to assess whole body range of motion, but further studies are needed to standardize technical procedures to obtain more accurate data.

Cutaneous pain experienced during locomotor training was previously reported to interfere with retention assessed in pain-free conditions. To determine whether this interference reflects consolidation deficits or a difficulty to transfer motor skills acquired in the presence of pain to a pain-free context, this study evaluated the effect of pain induced during both the acquisition and retention phases of locomotor learning. Healthy participants performed a locomotor adaptation task (robotized orthosis perturbing ankle movements during swing) on two consecutive days. Capsaicin cream was applied around participants’ ankle on both days for the Pain group, while the Control group was always pain-free. Changes in movement errors caused by the perturbation were measured to assess global motor performance; temporal distribution of errors and electromyographic activity were used to characterize motor strategies. Pain did not interfere with global performance during the acquisition or the retention phases but was associated with a shift in movement error center of gravity to later in the swing phase, suggesting a reduction in anticipatory strategy. Therefore, previously reported retention deficits could be explained by contextual changes between acquisition and retention tests. This difficulty in transferring skills from one context to another could be due to pain-related changes in motor strategy.

Abstract Background While minimalist running shoes may have an influence on running biomechanics and on the incidence of overuse injuries, the term “minimalist” is currently used without standardisation. The objectives of this study were to reach a consensus on a standard definition of minimalist running shoes, and to develop and validate a rating scale that could be used to determine the degree of minimalism of running shoes, the Minimalist Index (MI). Methods For this modified Delphi study, 42 experts from 11 countries completed four electronic questionnaires on an optimal definition of minimalist shoes and on elements to include within the MI. Once MI was developed following consensus, 85 participants subjectively ranked randomly assigned footwear models from the most to the least minimalist and rated their degree of minimalism using visual analog scales (VAS), before evaluating the same footwear models using MI. A subsample of thirty participants reassessed the same shoes on another occasion. Construct validity and inter‐ and intra‐rater reliability (intraclass correlation coefficients [ICC]; Gwet's AC1) of MI were evaluated. Results The following definition of minimalist shoes was agreed upon by 95 % of participants: “Footwear providing minimal interference with the natural movement of the foot due to its high flexibility, low heel to toe drop, weight and stack height, and the absence of motion control and stability devices”. Characteristics to be included in MI were weight, flexibility, heel to toe drop, stack height and motion control/stability devices, each subscale carrying equal weighing (20 %) on final score. Total MI score was highly correlated with VAS (r = 0.91). A significant rank effect (p

Most patients receiving intensive rehabilitation to improve their upper limb function experience pain. Despite this, the impact of pain on the ability to learn a specific motor task is still unknown. The aim of this study was to determine whether the presence of experimental tonic pain interferes with the acquisition and retention stages of motor learning associated with training in a reaching task. Twenty-nine healthy subjects were randomized to either a Control or Pain Group (receiving topical capsaicin cream on the upper arm during training on Day 1). On two consecutive days, subjects made ballistic movements towards two targets (NEAR/FAR) using a robotized exoskeleton. On Day 1, the task was performed without (baseline) and with a force field (adaptation). The adaptation task was repeated on Day 2. Task performance was assessed using index distance from the target at the end of the reaching movement. Motor planning was assessed using initial angle of deviation of index trajectory from a straight line to the target. Results show that tonic pain did not affect baseline reaching. Both groups improved task performance across time (p

The hybrid zone between the primarily forest-dwelling American toad, Anaxyrus americanus, and the prairie-adapted Canadian toad, A. hemiophrys, in southeastern Manitoba is known to have shifted its position during the past 50 years. Hybrid zones are areas of interbreeding between species and their movement across a landscape should reflect their underlying dynamics and environmental change. However, empirical demonstrations of hybrid zone movements over long periods of time are rare. This hybrid zone is dominated by individuals of intermediate morphology and genetic composition. We sought to determine if it had continued to move and if that movement was associated with shifts in habitat, as predicted.We used variation in the toads' most diagnostic morphological feature, the separation between their interorbital cranial crests, to determine the geographic position of the hybrid zone center at four times between 1960 and 2009 using maximum likelihood methods. The hybrid zone center moved west by 38 km over 19 years and then east again by 10 km over the succeeding 29 years. The position of the hybrid zone did not track either the direction or the magnitude of movement of the forest-prairie habitat transition over the same time period.This is the first reported evidence of oscillation in the position of a hybrid zone. The back and forth movement indicates that neither species maintains a selective advantage over the other in the long term. However, the movement of the hybrid zone was not bounded by the breadth of the habitat transition. Its oscillation suggests that the hybrid zone is better described as being elastically tethered to the habitat transition.