Assessing standing balance with MOTI: a validation study.

OBJECTIVES: This study aimed to determine the validity and reliability of a new device called MOTI for measuring balance by comparing its performance that with of the gold-standard force platform. METHODS: The study involved collecting data from both devices in dual- and single-leg standing positions with eyes open and closed and using statistical measures to compare their performance. RESULTS: The results showed that MOTI can accurately measure balance during dual-leg standing tasks but has poor to moderate performance during single-leg standing tasks. However, it could detect small changes in postural sway caused by a reduced base of support and/or visual feedback. The study also found that the test-retest reliability was poor to moderate for both devices. CONCLUSIONS: These findings suggest that MOTI has potential as a reliable tool for measuring balance during certain tasks, but further research is needed to improve its performance during single-leg standing. This study provides valuable insights into the validity and reliability of MOTI for measuring balance and highlights the need for further investigation.

Sensory, functional and electromyographic variables show different recovery patterns over a seven day period following exercise-induced pain in the hamstrings.

BACKGROUND: Delayed-onset muscle soreness (DOMS) is common after unaccustomed exercises and can restrict performance if intense physical activities are performed while the muscle is still sore. This study aimed to evaluate the recovery process following exercise-induced DOMS over a seven-day period by evaluating sensory, functional, and electromyographic parameters. METHODS: Twenty-four healthy males participated in four experimental sessions (Day-0, Day-2, Day-4, Day-7). Pain perception, pressure pain sensitivity, active range of motion, maximal isometric strength, and muscle activity of the hamstrings during the maximal isometric contraction were assessed bilaterally at each session. A single-leg deadlift eccentric exercise (5-sets of 20-reps) was performed at the end of Day-0 to induce DOMS in the dominant leg. FINDINGS: At Day-2, the DOMS-side showed increased pain sensitivity and decreased active range of motion, strength and muscle activity compared to Day-0 (P < 0.015). Muscle activity on the DOMS-side reached similar values than at baseline on Day-4, whereas pain perception, pressure pain sensitivity, maximal isometric strength, and active range of motion had returned to the baseline state on Day-7. No changes over time were observed on the control-side, showing all variables an excellent reliability between values at Day-0 and Day-7 (Intraclass Correlation Coefficient > 0.90). INTERPRETATION: Surface electromyographic values during a maximal isometric contraction recover faster than the other parameters. Given the heterogeneous path of altered variables towards DOMS recovery, trainers and clinicians should consider a multimodal assessment, including quantitative sensory and functional measures in addition to the subjective perception of recovery.

Validity of an inertial measurement unit for the assessment of range and quality of movement during head and thoracic spine movements.

BACKGROUND: Patients with spinal pain often exhibit movement limitations and altered motor control, which can be challenging to measure accurately in clinical practice. Inertial measurement sensors present a promising new opportunity to develop valid, low-cost, and easy-to-use methods for assessing and monitoring spinal motion in a clinical setting. AIM: This study aimed to investigate the agreement of an inertial sensor and a 3D camera system for assessing the range of motion (ROM) and quality of movement (QOM) in head and trunk single-plane movements. METHODS: Thirty-three healthy, pain-free volunteers were included. Each participant performed movements of the head (cervical flexion, extension, and lateral flexion) and trunk (trunk flexion, extension, rotation, and lateral flexion), which were simultaneously recorded by a 3D camera system and an inertial measurement unit (MOTI, Aalborg, Denmark). Agreement and consistency were analyzed for ROM and QOM by determining intraclass correlation coefficients (ICC), mean bias, and with Bland-Altman plots. RESULTS: The agreement between systems was excellent for all movements (ICC between 0.91 and 1.00) for ROM and good to excellent for the QOM (ICC between 0.84 and 0.95). The mean bias for all movements (0.1-0.8°) was below the minimum acceptable difference between devices. The Bland-Altman plot indicated that MOTI systematically measured a slightly greater ROM and QOM than the 3D camera system for all neck and trunk movements. CONCLUSION: This study showed that MOTI is a feasible and potentially applicable option to assess ROM and QOM for head and trunk movements in experimental and clinical settings.

Cross-cultural translation and adaptation of the Danish version of the brief version of the 10-item Big Five Inventory.

BACKGROUND: Personality traits are associated with pain-related beliefs and coping strategies, and different chronic conditions are linked through specific personality profiles. This highlights the importance of having valid and reliable measures of personality traits for use in clinical and research settings when assessing patients in chronic pain. PURPOSE: To translate and cross-culturally adapt the 10-item Big Five Inventory (BFI-10) into Danish. METHODS: A bilingual expert panel (N = 4) and a panel of laymen (N = 8) translated and culturally adapted the questionnaire into Danish. Face validity was evaluated in a group of persons suffering from recurring or ongoing painful conditions (N = 9). Data were collected to evaluate the internal consistency, test-retest reliability and factor structure (N = 96). RESULTS: Some of the participants in the lay panel considered the questionnaire too short, considering its aim of assessing personality. Acceptable internal consistency was found for two out of five subscales (0.78 for both Extraversion and Neuroticism), while the internal consistency was non-acceptable for the remaining subscales (0.17-0.45). Test-retest reliability was acceptable for three subscales (0.80 for Neuroticism, 0.84 for Conscientiousness, and 0.85 for Extraversion). Assumptions for determining the factor structure were not met and therefore was this analysis omitted. DISCUSSION: Although face valid, only two out of five subscales had acceptable internal consistency and only three subscales had acceptable test-retest reliability. These findings indicate that interpreting findings regarding personality using the Danish BFI-10 should be done with caution.

Long-term consistency of clinical sensory testing measures for pain assessment.

Background: Understanding the stability of quantitative sensory tests (QSTs) over time is important to aid clinicians in selecting a battery of tests for assessing and monitoring patients. This study evaluated the short- and long-term reliability of selected QSTs. Methods: Twenty healthy women participated in three experimental sessions: Baseline, 2 weeks, and 6 months. Measurements included pressure pain thresholds (PPT) in the neck, upper back, and leg; Pressure-cuff pain tolerance around the upper-arm; conditioned pain modulation during a pressure-cuff stimulus; and referred pain following a suprathreshold pressure stimulation. Intraclass correlation coefficients (ICC) and minimum detectable change (MDC) were calculated. Results: Reliability for PPT was excellent for all sites at 2 weeks (ICC, 0.96-0.99; MDC, 22-55 kPa) and from good to excellent at 6 months (ICC, 0.88-0.95; MDC, 47-91 kPa). ICC for pressure-cuff pain tolerance indicated excellent reliability at both times (0.91-0.97). For conditioned pain modulation, reliability was moderate for all sites at 2 weeks (ICC, 0.57-0.74; MDC, 24%-35%), while it was moderate at the neck (ICC, 0.54; MDC, 27%) and poor at the upper back and leg at 6 months. ICC for referred pain areas was excellent at 2 weeks (0.90) and good at 6 months (0.86). Conclusions: PPT, pressure pain tolerance, and pressure-induced referred pain should be considered reliable procedures to assess the pain-sensory profile over time. In contrast, conditioned pain modulation was shown to be unstable. Future studies prospectively analyzing the pain-sensory profile will be able to better calculate appropriate sample sizes.

Prolonged slumped sitting causes neck pain and increased axioscapular muscle activity during a computer task in healthy participants - A randomized crossover study.

INTRODUCTION: Sitting posture may contribute to spinal pain. Effects of postures on pain, sensitivity and muscle activity during computer tasks were investigated. METHODS: Twenty-five healthy participants, seated at a workstation without backrest, completed four, 15-min typing tasks: A)Upright with forearm-support; B)Upright without forearm-support; C)Slumped with forearm-support; D)Slumped without forearm-support. Participants rated pain every minute on a numerical rating scale (NRS). RMS-EMG was recorded from upper/lower trapezius (UT, LT), serratus anterior and anterior/middle deltoid. At baseline and after tasks, pressure pain thresholds (PPTs) were recorded bilaterally over the head, UT, and leg. RESULTS: All tasks caused clinically relevant increased NRS (≥2/10) compared to baseline (P < 0.001). NRS was higher in Task-D (P < 0.003) and lower in Task-B (P < 0.005) than others. PPTs did not change from baseline. Task-D caused higher UT and LT RMS-EMG (P < 0.02) than other tasks. CONCLUSION: A 15-min task caused pain irrespective of posture with some causing larger changes than others.

Not just sensitization: sympathetic mechanisms contribute to expand experimental referred pain.

Background: Widespread pain partially depends upon sensitization of central pain mechanisms. However, mechanisms controlling pain distribution are not completely known. The present study sought to assess skin temperature variations in the area of experimentally-induced pain and potential sex differences. Methods: Pressure-pain thresholds (PPTs) were measured on the right infraspinatus muscle. At the end of Day 0, all participants performed an eccentric exercise of the shoulder external rotators to induce muscle soreness 24 hours after. On Day 1, participants indicated on a body chart the area of pain induced by 60 seconds of suprathreshold pressure stimulation (STPS; PPT + 20%) on the right infraspinatus muscle. Skin temperature variations in the area of referred pain were recorded with an infrared thermography camera, immediately before and after the STPS. Results: Twenty healthy, pain-free individuals (10 females) participated. On Day 0, the pre-STPS temperature was higher than the post-STPS temperature on the arm (P = 0.001) and forearm (P = 0.003). On Day 1, the pre-STPS temperature was higher than the post-STPS temperature on the shoulder (P = 0.015), arm (P = 0.001), and forearm (P = 0.010). On Day 0, the temperature decrease after STPS in females was greater than in males on the forearm (P = 0.039). On Day 1, a greater temperature decrease was found amongst females compared with males at the shoulder (P = 0.018), arm (P = 0.046), and forearm (P = 0.005). Conclusions: These findings indicate that sympathetic vasomotor responses contribute to expand pressure-induced referred pain, especially among females.

Development of the Prevent for Work Questionnaire (P4Wq) for the assessment of musculoskeletal risk factors in the workplace: part 2-pilot study for questionnaire development and validation.

OBJECTIVE: The aim of this study was to develop a multifactorial, self-report questionnaire: Prevent for Work Questionnaire (P4Wq). The questionnaire is intended for screening for risk factors in work-related musculoskeletal disorders (WMSDs). DESIGN: Data were collected from otherwise healthy workers employed in three service areas at a specialist hospital in Italy: healthcare, administration and ancillary services. SETTING AND PARTICIPANTS: In all, 115 participants were enrolled (67% women; average age 41.5±9.94 years). The content of the tool for WMSDs was derived from three participation rounds of analysis involving a select group of experts who identified the questionnaire domains and items. Participants responded to 89 items in addition to the EuroQol 5 Dimensions Questionnaire (EQ-5D-5L), Fear-Avoidance Beliefs Questionnaire (FABq) and Oswestry Disability Index (ODI). The proportion of missing data and the distribution of responses were analysed for each item. Items with a discrimination index >0.40 and an interitem correlation <0.80 were retained. Factor analysis was performed using the VARIMAX rotation method, factor extraction, and identification, assignment of items to subscales, and assignment of scores to items. Internal consistency, reliability, construct validity and face validity were also assessed. RESULTS: A total of 52 items were included in the factor analysis and four subscales identified: Physical Stress Subscore (six items); Mental Stress Subscore (six items); Job Satisfaction Subscore (four items) and Kinesiophobia/Catastrophizing Subscore (four items). The items in the final questionnaire version had a factor loading >0.7. The questionnaire consisted of 20 items with good internal consistency (Cronbach's alpha 0.81-0.91), reliability (weighted kappa coefficient 0.617-1.00), good construct validity (EQ-5D-5L, r=-0.549, p<0.001; ODI, r=0.549, p<0.001; FABq work, r=0.688, p<0.001) and satisfactory face validity (universal validity index 96.04%). CONCLUSION: The P4Wq is a 20-item, multifactorial self-report risk assessment questionnaire. It may provide a useful tool for screening for WMSDs by specifically addressing back disorders. It investigates risks for individual workers and may inform educational programmes and preventive strategies tailored to a worker's needs. TRIAL REGISTRATION NUMBER: NCT04192604.

European knowledge alliance for innovative measures in prevention of work-related musculoskeletal pain disorders (Prevent4Work Project): protocol for an international mixed-methods longitudinal study.

INTRODUCTION: Work-related musculoskeletal (MSK) pain is a highly prevalent condition and one of the main contributors to disability and loss of work capacity. Current approaches to the management and prevention of work-related MSK pain do not consistently integrate current evidence-based knowledge and seem to be outdated. The Prevent4Work (P4W) Project aims to collect and spread evidence-based information to improve the management and prevention of work-related MSK pain. P4W will longitudinally investigate (1) risk factors associated with the prevalence of work-related MSK pain, (2) predictive factors for new events of work-related MSK pain in the short term and (3) the modification of pain beliefs after participating in evidence-based e-learning courses. METHODS AND ANALYSIS: This project employs a mixed-methods design with international cohorts of workers from Spain, Italy and Denmark. All participants will be assessed using self-reported variables at baseline (ie, cross-sectional design) with follow-up after 3 and 6 months (ie, prospective-predictive design). Throughout the first phase (0-3 months), all participants will be offered to self-enrol in e-learning courses on work-related MSK pain. Changes in pain beliefs (if any) will be assessed. The dataset will include sociodemographic characteristics, physical and psychological job demands, lifestyle-related factors, MSK pain history and pain beliefs. At baseline, all participants will additionally complete the P4W questionnaire developed to detect populations at high risk of suffering work-related MSK pain.Descriptive statistics, binary logistic regression, and analysis of variance will be used to identify the significant factors that influence the history of work-related MSK pain, evaluate the short-term prediction capacity of the P4W questionnaire, and investigate whether workers' participation in e-learning courses will modify their pain beliefs. ETHICS AND DISSEMINATION: The study received ethical approval from the Ethical Committee of San Jorge University (USJ011-19/20). The results will be made available via peer-reviewed publications, international conferences and P4W official channels.

The tolerance to stretch is linked with endogenous modulation of pain.

OBJECTIVES: The effect of stretching on joint range of motion is well documented, and although sensory perception has significance for changes in the tolerance to stretch following stretching the underlining mechanisms responsible for these changes is insufficiently understood. The aim of this study was to examine the influence of endogenous pain inhibitory mechanisms on stretch tolerance and to investigate the relationship between range of motion and changes in pain sensitivity. METHODS: Nineteen healthy males participated in this randomized, repeated-measures crossover study, conducted on 2 separate days. Knee extension range of motion, passive resistive torque, and pressure pain thresholds were recorded before, after, and 10 min after each of four experimental conditions; (i) Exercise-induced hypoalgesia, (ii) two bouts of static stretching, (iii) resting, and (iv) a remote, painful stimulus induced by the cold pressor test. RESULTS: Exercise-induced hypoalgesia and cold pressor test caused an increase in range of motion (p<0.034) and pressure pain thresholds (p<0.027). Moderate correlations in pressure pain thresholds were found between exercise-induced hypoalgesia and static stretch (Rho>0.507, p=0.01) and exercise-induced hypoalgesia and the cold pressor test (Rho=0.562, p=0.01). A weak correlation in pressure pain thresholds and changes in range of motion were found following the cold pressor test (Rho=0.460, p=0.047). However, a potential carryover hypoalgesic effect may have affected the results of the static stretch. CONCLUSIONS: These results suggest that stretch tolerance may be linked with endogenous modulation of pain. Present results suggest, that stretch tolerance may merely be a marker for pain sensitivity which may have clinical significance given that stretching is often prescribed in the rehabilitation of different musculoskeletal pain conditions where reduced endogenous pain inhibition is frequently seen.

Development of the Prevent for Work questionnaire (P4Wq) for assessment of musculoskeletal risk in the workplace: part 1-literature review and domains selection.

OBJECTIVE: This study aims to define appropriate domains and items for the development of a self-administered questionnaire to assess the risk of developing work-related musculoskeletal disorder (WMSD) and the risk of its progression to chronicity. DESIGN: Literature review and survey study. SETTING AND PARTICIPANTS: A literature review and a two-round interview with 15 experts in musculoskeletal pain were performed to identify the available domains for WMSD assessment. INTERVENTIONS AND OUTCOME: To ensure quality, only validated questionnaires were included for the Delphi process. A three-round Delphi method, with three round steps, was used to select the most pertinent and relevant domains and items. RESULTS: Nine questionnaires were identified through the expert discussion and literature review, comprising 38 candidate domains and 504 items. In the first round of the Delphi group, 17 domains reached more than 70% agreement and were selected. In the second round, 10 domains were rejected, while 11 were selected to complete the pool of domains. In the third and final round, 89 items belonging to 28 domains were defined as significant to develop a WMSDs risk assessment questionnaire. CONCLUSIONS: No specific risk assessment questionnaires for WMSDs were identified from the literature. WMSD risk of presence and chronicity can be defined by an assessment tool based on the biopsychosocial model and the fear-avoidance components of chronic pain. The present study provides the formulation and operationalisation of the constructs in domains and items needed for developing and validating the questionnaire.

The Area of Pressure-Induced Referred Pain Is Dependent on the Intensity of the Suprathreshold Stimulus: An Explorative Study.

OBJECTIVE: To investigate the pain referral area (number of pixels) and extent (vector length) as elicited from increasing intensities of pressure-induced pain at the shoulder. DESIGN: Cross-sectional design. SETTING: Clinical laboratory setting. PARTICIPANTS: Twenty-two healthy men and women participated in two experimental sessions. METHODS: Delayed onset of muscle soreness (DOMS) was induced in the dominant shoulder and assessed 24 hours later. Participants rated the level of DOMS on a 6-point Likert scale. Four different intensities (pressure pain threshold [PPT]+20%, PPT+30%, PPT+40%, and PPT+50%) were applied to the infraspinatus in a randomized, balanced fashion for 60 seconds from low to high intensity or vice versa. The resulting location, area, and extent of referred pain as drawn by the participants on a digital body chart were extracted and expressed in pixels. The extent of pain was defined as the vector length extending from the ipsilateral earlobe to the most distal location of the pain. RESULTS: The referred pain area from PPT+20% was smaller than PPT+30%, PPT+40%, and PPT+50%. The extent of referred pain did not differ between the pressure pain intensities. CONCLUSIONS: Pressure intensity at PPT+30%, but no more, produces the greatest referred pain area as compared with the traditional pressure intensity of PPT+20%. Thus, the intensity of PPT+30% may be ideal for exploring the mechanisms of referred pain. The extent of the pain represents an independent expression of the intensity of the provoking stimulus and may be more closely related to the location of the stimulus.

"Study protocol for the ≥65 years NOrthern jutland Cohort of Fall risk Assessment with Objective measurements (the NOCfao study)".

BACKGROUND: Accidental falls are common among community-dwellers, probably due to the level of physical activity and impaired postural stability. Today, fall risk prediction tools' discriminative validity are only moderate. In order to increase the accuracy, multiple variables such as highly validated objective field measurements of physical activity and impaired postural stability should be adressed in order to predict falls. The main aim of this paper is to describe the ≥65 years NOrthern jutland Cohort of Fall risk Assessment with Objective measurements (NOCfao) investigating the association between physical activity and impaired postural stability and the risk of fall episodes among community-dwelling older adults. METHODS: The study consists of a baseline session where the participants are asked to respond to three questionnaires, perform physical tests (i.e., measuring strength in the upper and lower extremities, balance, and walking speed), participate in an assessment of pain sensitivity, and to wear an ankle mounted pedometer for measuring physical activity for 5 days. Subsequently, the fall incidences and the circumstances surrounding the falls during the previous 1 to 2 months will be recorded throughout a one-year follow-up period. DISCUSSION: This study will add to the present-day understanding of the association between physical activity and impaired postural stability and the risk of fall episodes among community-dwelling older adults. These data will provide valid and reliable information on the relationship between these variables and their significance for community-dwelling older adults. TRIAL REGISTRATION: ClinicalTrials.gov identifier: NCT2995317. Registered December 13th, 2016.

Improvements in clinical pain and experimental pain sensitivity after cognitive functional therapy in patients with severe persistent low back pain.

INTRODUCTION: Multidisciplinary care is recommended for disabling persistent low back pain (pLBP) nonresponsive to primary care. Cognitive functional therapy (CFT) is a physiotherapy-led individualised intervention targeting psychological, physical, and lifestyle barriers to recovery, to self-manage pLBP. OBJECTIVES: This pilot study investigated clinical outcomes and pain thresholds after a 12-week CFT pathway in patients with severe pLBP referred to a University Pain Center. Exploratory analyses compared changes in clinical outcomes, opioid consumption, and costs after CFT with changes after a multidisciplinary pain management (MPM) pathway. METHODS: In total, 47 consecutively referred pLBP patients consented to the CFT pathway. At baseline, 3 and 6 months, clinical outcomes and PPTs were assessed. Control patients (n = 99) who had completed an MPM pathway in the last 3 years were matched from the clinical pain registry used in the Pain Center in a 3:1 ratio based on propensity scores derived from relevant baseline variables of the CFT cases. RESULTS: Most clinical outcomes and low back pressure pain threshold were improved at 3 and 6 months after the CFT pathway. Compared with MPM, CFT patients had significantly larger reductions in disability and improved quality of life after the interventions at a lower cost (-3688€ [confidence interval: -3063 to -4314€]). Reduction in pain intensity and proportion of patients withdrawing from opioids (18.2% vs 27.8%) were similar between CFT and MPM groups. CONCLUSION: Improvements in clinical and experimental pain were found after the CFT pathway. Fully powered randomized controlled trials comparing CFT with an MPM program in patients with disabling pLBP are warranted to control for the current limitations.

Education as a strategy for managing occupational-related musculoskeletal pain: a scoping review.

BACKGROUND: Musculoskeletal (MSK) pain is the primary contributor to disability worldwide. There is a growing consensus that MSK pain is a recurrent multifactorial condition underpinned by health and lifestyle factors. Studies suggest that education on work-related pain and individualised advice could be essential and effective for managing persistent MSK pain. OBJECTIVE: The objective of this scoping review was to map the existing educational resources for work-related MSK (WRMSK) pain, and the effects of implementing educational strategies in the workplace on managing WRMSK pain. METHODS: This scoping review assessed original studies that implemented and assessed education as a strategy to manage WMSK pain. Literature search strategies were developed using thesaurus headings (ie, MeSH and CINAHL headings) and free-text search including words related to MSK in an occupational setting. The search was carried out in PubMed, CINAHL, Cochrane Library and Web of Science in the period 12-14 February 2019. RESULTS: A total of 19 peer-reviewed articles were included and the study design, aim and outcomes were summarised. Of the 19 peer-reviewed articles, 10 randomised controlled trial (RCT) studies assessed the influence of education on work-related MSK pain. Many studies provided a limited description of the education material and assessed/used different methods of delivery. A majority of studies concluded education positively influences work-related MSK pain. Further, some studies reported additive effects of physical activity or ergonomic adjustments. CONCLUSIONS: There is a gap in knowledge regarding the best content and delivery of education of material in the workplace. Although beneficial outcomes were reported, more RCT studies are required to determine the effects of education material as compared with other interventions, such as exercise or behavioural therapy.

Cross-cultural adaptation of the Danish version of the Big Five Inventory - a dual-panel approach.

Background and aims Assessing personality in research can be of importance, especially due to the potential relationship between different personality traits and the manifestation of symptoms in different clinical conditions. Therefore, it is important to have valid and reliable tools that allow for the assessment of personality traits. In this study, the aim was to translate and culturally adapt the Big Five Inventory (BFI) to the Danish language. Methods A dual panel approach, consisting of a 4-person bilingual panel and an 8-person panel with laymen, was used to translate and culturally adapt the questionnaire. A third 9-person panel consisting of people with different medical diagnosis was used to assess the face validity. Internal consistency (Cronbach's α) and test-retest reliability (intraclass correlation coefficients (ICC)) were tested amongst 96 subjects. Results The translated version demonstrated adequate internal consistency (0.66-0.84) and good-excellent test-retest reliability (0.86-0.95). The smallest detectable change is between 1.13-1.70 for the five subscales. Both the healthy and patient panels of laymen considered the questionnaire too long. Conclusion This translated version of the Big Five Inventory demonstrated high to very high test-retest reliability and, for most parts, an acceptable internal consistency. The construct validity was however different from versions translated into languages geographically and culturally similar to Danish. Implications Assessing the Big Five personality traits in Danish populations can be valuable for many reasons, e.g. when assessing people in pain in both clinical and experimental settings. Improved knowledge of the underlying driver of pain conditions is important. Here, understanding how personality may interact with pain can help researchers and clinicians.

The use of posture-correcting shirts for managing musculoskeletal pain is not supported by current evidence - a scoping review of the literature.

BACKGROUND AND AIMS: The concept of bad posture being a dominant driver of pain is commonly held belief in the society. This may explain the significant attention supportive clothing such as posture-correcting shirts has recently gained in Scandinavia and the USA. The aim of this scoping review was to present an overview and synthesis of the available evidence for the use of posture-correcting shirts aimed at reducing pain or postural discomfort and optimising function/posture. METHODS: A systematic search was conducted for literature investigating the effect of posture-correcting shirts on musculoskeletal pain or function. PubMed, Embase, CINAHL, PEDro and the Cochrane Library were searched for relevant literature. Results of the searches were evaluated by two independent reviewers in three separate steps based on title, abstract and full text. For data synthesis, the population, intervention, comparator and outcome were extracted. The quality of the literature was evaluated using the Quality Assessment Tool for Observational Cohort and Cross-Sectional Studies and the risk of bias was assessed using the Risk Of Bias In Non-randomized Studies - of Interventions (ROBINS-I) assessment tool or the RoB 2.0 tool for individually randomized, parallel group trials. The overall confidence in the literature was determined using the Grading of Recommendations Assessment, Development and Evaluation (GRADE). RESULTS: A total of 136 articles were identified and six of these were included in the review. These studies were heterogeneous with regards to aims, outcomes and methods, presenting contrasting results. The overall findings were that posture-correcting shirts change posture and subjectively have a positive effect on discomfort, energy levels and productivity. The quality of the included literature was poor to fair with only one study being of good quality. The risk of bias was serious or critical for the included studies. Overall, this resulted in very low confidence in available evidence. An important limitation of all studies was that they were conducted in pain-free individuals. CONCLUSIONS: The contrasting findings and the low quality of current literature, questions the intended effect of posture-correcting shirts and whether the changes it creates are in fact useful for clinical practice. Moreover, the findings are contrasted by the available evidence regarding posture and pain with a particular focus on whether this management strategy may have a detrimental effect on people living with musculoskeletal pain. A major limitation to the existing literature on the effect of posture-correcting shirts is that no studies have investigated their effect in clinical populations. IMPLICATIONS: Based on the available literature and the major limitation of no studies investigating clinical populations, there is no good quality evidence to support recommendation of posture-correcting shirts as a management strategy for musculoskeletal pain. Promotion of this product may reinforce the inaccurate and unhelpful message that poor posture leads to pain. The efficacy of such garments should be tested in clinical populations and not only in pain-free individuals, to assess whether there is any meaningful benefit of this management approach. Until then, the use of posture-correcting shirts for musculoskeletal pain is not supported by current evidence.

Muscle stretching - the potential role of endogenous pain inhibitory modulation on stretch tolerance.

Background and aims The effect of stretching on joint range of motion is well documented and is primarily related to changes in the tolerance to stretch, but the mechanisms underlying this change are still largely unknown. The aim of this study was to investigate the influence of a remote, painful stimulus on stretch tolerance. Methods Thirty-four healthy male subjects were recruited and randomly assigned to an experimental pain group (n=17) or a control group (n=17). Passive knee extension range of motion, the activity of hamstring muscles and passive resistive torque were measured with subjects in a seated position. Three consecutive measures were performed with a 5-min interval between. A static stretch protocol was utilized in both groups to examine the effect of stretching and differences in stretch tolerance between groups. Following this, the pain-group performed a cold pressor test which is known to engage the endogenous pain inhibitory system after which measurements were repeated. Results A significant increase in knee extension range of motion was found in the pain group compared with controls (ANCOVA: p<0.05). No difference was found in muscle activity or passive resistive torque between groups (ANCOVA p>0.091). Conclusions Passive knee extension range of motion following stretching increased when following a distant, painful stimulus, potentially engaging the endogenous pain inhibitory systems. Current findings indicate a link between increased tolerance to stretch and endogenous pain inhibition. Implications The current findings may have implications for clinical practice as they indicate that a distant painful stimulus can influence range of motion in healthy individuals. This implies that the modulation of pain has significance for the efficacy of stretching which is important knowledge when prescribing stretching as part of rehabilitation.

Correlations between the active straight leg raise, sleep and somatosensory sensitivity during pregnancy with post-partum lumbopelvic pain: an initial exploration.

Background and aims For some women, lumbopelvic pain (LPP) developed during pregnancy becomes a continuing post-partum problem. Increased understanding of potential prognostic factors is required. This study investigated whether active straight leg raise (ASLR), sleep dysfunction and pressure pain sensitivity during pregnancy are correlated with LPP intensity and quality, disability, and physical health-related quality of life (HRQoL) post-partum. Methods An exploratory, prospective cohort study design was used. Baseline factors of interest were: (1) ASLR, (2) Pittsburgh Sleep Quality Index, and (3) pressure pain thresholds (PPTs) collected from pregnant women from sites local and distal to the lumbopelvic area. Follow-up data collected 11-18 months post-partum (n=29) were: (1) pain intensity score (numerical rating scale), (2) pain quality (McGill Pain Questionnaire), (3) disability (Pelvic Girdle Questionnaire), and (4) HRQoL (36-item Short Form Health Survey). Correlation analysis was performed. Results Greater difficulty with an ASLR during pregnancy correlated with lower post-partum physical HRQoL scores (r=-0.563, p=0.002). Likewise, reduced PPTs at the sacrum during pregnancy was correlated with a higher post-partum pain quality score (r=-0.384, p=0.040). Conclusions In this cohort, findings indicate that poor ASLR performance and localised pressure pain hypersensitivity at the pelvis during pregnancy are correlated with post-partum physical HRQoL and pain quality, respectively. Implications Pain sensitivity may contribute to the prognosis of women with LPP during pregnancy. These explorative findings may be important for designing larger prognostic studies and may assist in directing potential pain management in post-partum LPP.