Factors associated with the Single Leg Squat test in female soccer players: a cross-sectional study

BACKGROUND

The Single Leg Squat (SLS) test is widely used in the clinical setting to examine and evaluate rehabilitation goals. It is simple to perform and is proposed to have biomechanical and neuromuscular similarities to athletic movements. The aim of the present study was to investigate whether demographics, previous injuries, and biomechanical and psychosocial factors are associated with the outcome of the SLS, assessed as a total score for all segments and as a separate knee segment in elite and sub-elite female soccer players.

METHODS

We conducted a cross-sectional study involving 254 female soccer players (22 yrs; SD ± 4, height 1.69 m; SD ± 0.1, weight 64 kg; SD ± 6) from divisions 1-3 of the Swedish Soccer League. During the preseason, we assessed the participants using the SLS and tested their hip strength and ankle mobility. Demographics, previous injury, sleep quality, fear of movement, anxiety, and perceived stress were assessed with questionnaires. Logistic regression models were built to analyse the association between the outcome of the SLS and the independent variables for the dominant and non-dominant leg.

RESULTS

Significantly more participants failed the SLS on the dominant leg compared with the non-dominant leg (p < 0.001). The outcome of the SLS associated with various biopsychosocial factors depending on if the dominant or non-dominant leg was tested. The total score associated with hip strength for the dominant (OR 0.99, 95% CI 0.98-0.99, p = 0.04) and the non-dominant leg (OR 0.99, 95% CI 0.97-0.99, p = 0.03). The knee segment associated with division level for the dominant (div 2; OR 2.34, 95% CI 1.01-5.12, p = 0.033. div 3; OR 3.07, 95% CI 1.61-5.85, p = 0.001) and non-dominant leg (div 2; OR 3.30, 95% CI 1.33-8.00, p = 0.01. div 3; OR 3.05, 95% CI 1.44-6.43, p = 0.003).

CONCLUSIONS

This study identified that leg dominance, division level, hip strength, and psychosocial factors were associated with the outcome of the SLS when assessed as a total score and as a separate knee segment. This indicates that clinicians need to understand that movement control is associated with factors from several domains. Whether these factors and, the results of the SLS are related to injury need to be studied prospectively.

TRIAL REGISTRATION

Clinical Trials Gov, date of registration 2022-03-01.

CLINICAL TRIALS IDENTIFIER

NCT05289284A.

Summarizing the effects of different exercise types in chronic neck pain - a systematic review and meta-analysis of systematic reviews

BACKGROUND

To date, no consensus exists as to whether one exercise type is more effective than another in chronic neck pain. This systematic review and meta-analysis of systematic reviews aimed to summarize the literature on the effect of various exercise types used in chronic neck pain and to assess the certainty of the evidence.

METHODS

We searched the databases Ovid MEDLINE, Embase, Cochrane Library, SportDiscus, and Web of Science (Core Collection) for systematic reviews and meta-analyses on adults between 18 and 70 years with chronic neck pain lasting ≥ 12 weeks which investigated the effects of exercises on pain and disability. The included reviews were grouped into motor control exercise (MCE), Pilates exercises, resistance training, traditional Chinese exercise (TCE), and yoga. Study quality was assessed with AMSTAR-2 and the level of certainty for the effects of the exercise through GRADE. A narrative analysis of the results was performed and in addition, meta-analyses when feasible.

RESULTS

Our database search resulted in 1,794 systematic reviews. We included 25 systematic reviews and meta-analyses including 17,321 participants (overlap not accounted for). The quality of the included reviews ranged from critically low to low (n = 13) to moderate to high (n = 12). We found low to high certainty of evidence that MCE, Pilates exercises, resistance training, TCE, and yoga have short-term positive effects on pain and that all exercise types except resistance training, show positive effects on disability compared to non-exercise controls. We found low to moderate certainty of evidence for conflicting results on pain and disability when the exercise types were compared to other exercise interventions in the short-term as well as in intermediate/long-term apart for yoga, as no long-term results were available.

CONCLUSION

Overall, our findings show low to high certainty of evidence for positive effects on pain and disability of the various exercise types used in chronic neck pain compared to non-exercise interventions, at least in the short-term. Based on our results, no optimal exercise intervention for patients with chronic neck pain can be recommended, since no large differences between the exercise types were shown here. Because the quality of the included systematic reviews varied greatly, future systematic reviews need to increase their methodological quality.

TRIAL REGISTRATION

Prospero CRD42022336014.

High- Versus Low-Dose Exercise Therapy for Knee Osteoarthritis : A Randomized Controlled Multicenter Trial

BACKGROUND

The benefits of exercise in patients with knee osteoarthritis are well documented, but the optimal exercise dose remains unknown.

OBJECTIVE

To compare high-dose versus low-dose exercise therapy with regard to knee function, pain, and quality of life (QoL) in patients with long-term symptomatic knee osteoarthritis.

DESIGN

A Swedish and Norwegian multicenter randomized controlled superiority trial with multiple follow-ups up to 12 months after the intervention. (ClinicalTrials.gov: NCT02024126).

SETTING

Primary health care facilities.

PATIENTS

189 patients with diagnosed knee osteoarthritis and a history of pain and decreased knee function were assigned to high-dose therapy (n = 98; 11 exercises; 70 to 90 minutes) or low-dose therapy (n = 91; 5 exercises; 20 to 30 minutes).

INTERVENTION

Patient-tailored exercise programs according to the principles of medical exercise therapy. Global (aerobic), semiglobal (multisegmental), and local (joint-specific) exercises were performed 3 times a week for 12 weeks under supervision of a physiotherapist.

MEASUREMENTS

The Knee Injury and Osteoarthritis Outcome Score (KOOS) was measured biweekly during the 3-month intervention period and at 6 and 12 months after the intervention. The primary end point was the mean difference in KOOS scores between groups at the end of the intervention (3 months). Secondary outcomes included pain intensity and QoL. The proportion of patients with minimal clinically important changes in primary and secondary outcomes was compared between groups.

RESULTS

Both groups improved over time, but there were no benefits of high-dose therapy in most comparisons. One exception was the KOOS score for function in sports and recreation, where high-dose therapy was superior at the end of treatment and at 6-month follow-up. A small benefit in QoL at 6 and 12 months was also observed.

LIMITATION

There was no control group that did not exercise.

CONCLUSION

The results do not support the superiority of high-dose exercise over low-dose exercise for most outcomes. However, small benefits with high-dose exercise were found for knee function in sports and recreation and for QoL.

PRIMARY FUNDING SOURCE

Swedish Rheumatic Fund.

Biomechanical analysis of lifting on stable versus unstable surfaces-a laboratory-based proof-of-concept study

Background

Many workers performing manual handling tasks suffer from musculoskeletal disorders (MSD). Previous research has identified several loading aspects associated with manual handling, but it is still unknown if lifting on an unstable surface is associated with increased biomechanical loading of different body parts.

Aim

This proof-of-concept study aims to study what kinematic and kinetic movement parameters, such as movement time, joint angles, torque, and muscle activity are feasible and of importance when studying the effect of lifting on surfaces with varying degrees of stability in an experimental set-up.

Methods

Measurements were taken during three different surface conditions: stable, slightly unstable, and unstable. The participants were instructed to lift a box from the floor and place it on a table in front of them. The weight of the box varied from 0.5 to 15.5 kg. By using a motion capture system (VICON) with 28 reflective markers placed on the participants and one on the box, one Kistler force plate for measuring force levels and center of pressure movements (CoP), and four electromyographic transmitters (EMG), we analyzed the downward and upward phases of the lifting movement, using the Friedman’s test for repeated measures.

Results

Statistically significant results with less joint movements in the lower and upper back were seen with increased instability during both the downward and upward phases. The decrease in trunk movements with increased instability resulted in a somewhat more flexed knee position during the movement, a lower torque in the lower back, and a decrease in CoP movements, but no differences in movement time or muscle activity in back and knee muscles.

Conclusion

Lifting while standing on unstable surfaces resulted in an alteration of both kinematics and kinetics parameters; however, further studies regarding whether this is an additional risk factor for developing lower back pain are needed. Muscle activity levels were not altered due to instability and due to the complexity of the measurement, and we suggest not including EMG measures in future experiments of this type.

Supplementary Information

The online version contains supplementary material available at 10.1186/s40814-022-01157-2.

Summarizing the effects of different exercise types in chronic low back pain - a systematic review of systematic reviews

Background

In chronic LBP (CLBP), guideline-endorsed treatment is to stay active, return to normal activity, and to exercise. Several reviews on various exercise types used in CLBP have been published. We aimed to identify systematic reviews of common exercise types used in CLBP, to appraise their quality, and to summarize and compare their effect on pain and disability.

Methods

We searched the databases OVID MEDLINE, EMBASE, COCHRANE LIBRARY, and WEB OF SCIENCE (Core collection) for systematic reviews and meta-analyses on adults between 18 and 70 years of age suffering from chronic or recurrent LBP for a period of at least 12 weeks, which investigated the effects of exercises on pain and disability. All searches were conducted without language restriction. The search was performed up until 2022–01-26. The included reviews were grouped into nine exercise types: aerobic training, aquatic exercises, motor control exercises (MCE), resistance training, Pilates, sling exercises, traditional Chinese exercises (TCE), walking, and yoga. The study quality was assessed with AMSTAR-2. For each exercise type, a narrative analysis was performed, and the level of evidence for the effects of exercise was assessed through GRADE.

Results

Our database search resulted in 3,475 systematic reviews. Out of the 253 full texts that were screened, we included 45 systematic reviews and meta-analyses. The quality of the included reviews ranged from high to critically low. Due to large heterogeneity, no meta-analyses were performed. We found low-to-moderate evidence of mainly short-term and small beneficial effects on pain and disability for MCE, Pilates, resistance training, TCE, and yoga compared to no or minimal intervention.

Conclusions

Our findings show that the effect of various exercise types used in CLBP on pain and disability varies with no major difference between exercise types. Many of the included systematic reviews were of low-to-moderate quality and based on randomized controlled trials with high risk of bias. The conflicting results seen, undermine the certainty of the results leading to very-low-to-moderate quality of evidence for our results. Future systematic reviews should be of higher quality to minimize waste of resources.

Trial registration

PROSPERO: Reg no 190409 Registration date 01AUG 2020.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12891-022-05722-x.

Socioeconomic variation of multimorbidity in Colombian older adults

Multimorbidity (MM) prevalence among older adults is increasing worldwide. Variations regarding the socioeconomic characteristics of the individuals and their context have been described, mostly in high-income settings. However, further research is needed to understand the effect of the coexistence of infectious diseases along with socioeconomic factors regarding MM. This study aims to examine the variation of MM regarding infectious diseases mortality after adjusting for socioeconomic factors. A cross-sectional multilevel study with a nationally representative sample of 17,571 Colombian adults of 60 years of age or older was conducted. Individual socioeconomic, demographic, childhood and health related characteristics, as well as group level variables (multidimensional poverty index and infectious diseases mortality rate) were analyzed. A two-level stepwise structural equation model was used to simultaneously adjust for the individual and contextual effects. Multimorbidity prevalence was 62.3% (95% CI 61.7–62.9). In the multilevel adjusted models, age, female sex, having functional limitations, non-white ethnicity, high body mass index, higher income, physical inactivity and living in urban areas were associated with multimorbidity among the sample for this study. The median odds ratio for multidimensional poverty was 1.18 (1.16–1.19; p = 0.008) and for infectious diseases was 1.25 (1.22–1.28; p = 0.014). This paper demonstrates that MM varies regarding the mortality of infectious diseases and shows a strong association between MM and poverty in a low-middle income country. Differences in the factors involved in the etiology of multimorbidity are expected among wealthy and poor countries regarding availability and prioritization of health services.

Reliability and validity of a novel Kinect-based software program for measuring a single leg squat

Background

The Single leg squat (SLS) is a movement screening test widely used in clinical settings. The SLS is highly subjective in its nature. Objective measures, such as 3D-motion analyses, are seldom used in daily clinical work. An interactive, Kinect-based 3D-movement analysis system, the Qinematic™, is proposed to be easily used in clinical settings to assess the SLS. The aim of this study was to establish the test-retest reliability and construct validity of Qinematic™ for assessing the SLS. A further aim was to identify angles of medial knee displacement, to summarise the discriminative ability of the SLS measured by Qinematic™.

Methods

We performed a test-retest reliability study (n = 37) of the SLS using Qinematic™ and a construct validity study, in which Qinematic™ data were compared with visual assessment of video-recorded SLS.

Results

Three variables (left knee down, right knee up and down) reached “substantial reliability” (ICC = 0.64–0.69). One variable, “left knee up”, showed a significant difference between the two test occasions (T1–6.34°, T2 0.66°, p = 0.013, ICC = 0.50), and “poor absolute reliability” was seen for all variables (SEM = 9.04–10.66, SDC = 25.06–29.55). A moderate agreement between the visual assessment and Qinematic™ data for various knee angles was shown (Kappa = 0.45–0.58). The best discriminative ability of the SLS was found at a knee angle of 6° (AUC = 0.82, sensitivity = 0.86, specificity = 0.78, PPV = 0.58, NPV = 0.94).

Conclusions

Qinematic™ shows a poor absolute reliability, and a substantial relative reliability, in measuring a SLS at the way down. This indicates that Qinematic™ should not be recommended for the use on an individual level, but it can possibly be used on a group level. The merged results of the construct validity study indicate that Qinematic™ at 6° of medial displacement can identify subjects with a knee over foot position. In summary, the use of the Qinematic™ net trajectory angle, which estimates the “line of best fit” cannot be recommended to assess a knee medial to foot position and should be reconsidered.

Visual assessment of movement quality in the single leg squat test: a review and meta-analysis of inter-rater and intrarater reliability

Single leg squat (SLS) is a common tool used in clinical examination to set and evaluate rehabilitation goals, but also to assess lower extremity function in active people.

Non-participation in initial and repeated health risk appraisals - a drop-out analysis based on a health project

BACKGROUND

Health risk assessment (HRAs) are commonly used by occupational health services (OHS) to aid workplaces in keeping their employees healthy, but for unknown reasons, many employees choose not to participate in the HRAs. The aim of the study was to explore whether demographic, lifestyle and health-related factors in employees are associated with non-participation in initial and repeated HRAs.

METHODS

In an OHS-based health project, 2022 municipal employees were asked to participate in three repeated HRAs. Multiple logistic regression analyses were used so as to determine associations between non-participating and demographic, lifestyle and health-related factors (e.g. biomarkers).

RESULTS

Among the employees who were asked to participate in the health project, more than half did not participate in any HRA and among those who did, more than one third did not participate in repeated HRAs. Young age, male sex and being employed in the Technical department or Health and Social Care department in comparison with being employed in the department for Childcare and Education were factors significantly associated with non-participation in the initial HRA. These factors, together with being on sick leave and having unhealthy dietary habits, were factors associated with non-participation in repeated HRAs.

CONCLUSIONS

Among the non-participators in initial HRAs and in repeated HRAs younger men and those already related to ill-health were overrepresented. This implicates that health care providers to a higher extent should focus on "those most needed" and that employers should be more engaged in results of repeated HRA's. Future studies should focus on modifiable variables that could make the HRAs more attractive and inclusive.

Elaborating on the assessment of the risk of bias in prognostic studies in pain rehabilitation using QUIPS-aspects of interrater agreement

BACKGROUND

Many studies have been performed to identify important prognostic factors for outcomes after rehabilitation of patients with chronic pain, and there is a need to synthesize them through systematic review. In this process, it is important to assess the study quality and risk of bias. The "Quality In Prognosis Studies" (QUIPS) tool has been developed for this purpose and consists of several prompting items categorized into six domains, and each domain is judged on a three-grade scale (low, moderate or high risk of bias). The aim of the present study was to determine the interrater agreement of the risk of bias assessment in prognostic studies of patients with chronic pain using QUIPS and to elaborate on the use of this instrument.

METHODS

We performed a systematic review and a meta-analysis of prognostic factors for long-term outcomes after multidisciplinary rehabilitation in patients with chronic pain. Two researchers rated the risk of bias in 43 published papers in two rounds (15 and 28 papers, respectively). The interrater agreement and Cohen's quadratic weighted kappa coefficient (κ) and 95% confidence interval (95%CI) were calculated in all domains and separately for the first and second rounds.

RESULTS

The raters agreed in 61% of the domains (157 out of 258), with similar interrater agreement in the first (59%, 53/90) and second rounds (62%, 104/168). The overall weighted kappa coefficient (kappa for all domains and all papers) was weak: κ = 0.475 (95%CI = 0.358-0.601). A "minimal agreement" between the raters was found in the first round, κ = 0.323 (95%CI = 0.129-0.517), but increased to "weak agreement" in the second round, κ = 0.536 (95%CI = 0.390-0.682).

CONCLUSION

Despite a relatively low interrater agreement, QUIPS proved to be a useful tool in assessing the risk of bias when performing a meta-analysis of prognostic studies in pain rehabilitation, since it demands of raters to discuss and investigate important aspects of study quality. Some items were particularly hard to differentiate in-between, and a learning phase was required to increase the interrater agreement. This paper highlights several aspects of the tool that should be kept in mind when rating the risk of bias in prognostic studies, and provides some suggestions on common pitfalls to avoid during this process.

TRIAL REGISTRATION

PROSPERO CRD42016025339; registered 05 February 2016.

Observational Methods for Assessing Ergonomic Risks for work-related musculoskeletal disorders. A Scoping Review

Introducción: Los desórdenes músculo-esqueléticos relacionados con el trabajo (DME) son una de las causas más comunes de la ausencia laboral. Las exposiciones en el entorno de trabajo pueden causar o agravar el impacto de estos desórdenes músculo-esqueléticos y la identificación de exposiciones ergonómicas es esencial en la evaluación de riesgos. Es importante evaluar los tres indicadores clave de estas exposiciones (intensidad, frecuencia y duración) para poder estimar el nivel de riesgo para el desarrollo de dme. Objetivo: Este artículo tiene como objetivo proporcionar una visión general de algunos de los métodos de observación que se pueden utilizar para evaluar los riesgos ergonómicos en el lugar de trabajo. Métodos: Este estudio se realizó como una revisión del alcance de la literatura médica y ergonómica y de las páginas web gubernamentales o ciales en Suecia, EE. UU. Y los Países Bajos. Resultados: En total, se identificaron 19 métodos de observación diferentes. Resumimos nuestros hallazgos en función de las partes del cuerpo que se estudiaron y los indicadores clave evaluados: 1) la intensidad de la carga de trabajo (postura y producción de fuerza), 2) la frecuencia de la carga de trabajo (por ejemplo, movimientos repetitivos) y 3) la duración de la carga de trabajo (por ejemplo, trabajo estático). En un apéndice incluimos una breve presentación de estos métodos junto con la hoja de trabajo (si estaba disponible) y la fuente de referencia del método de observación. Conclusión: Para los ergónomos que realizan evaluaciones de riesgo hay una gran cantidad de herramientas de evaluación observacional disponibles y es importante comprender que se pueden usar diferentes métodos simultáneamente para poder estimar los niveles de riesgo objetivo para DME.

Reliability and validity of a novel Kinect-based software program for measuring posture, balance and side-bending

Background

Clinical examinations are subjective and often show a low validity and reliability. Objective and highly reliable quantitative assessments are available in laboratory settings using 3D motion analysis, but these systems are too expensive to use for simple clinical examinations. Qinematic™ is an interactive movement analyses system based on the Kinect camera and is an easy-to-use clinical measurement system for assessing posture, balance and side-bending. The aim of the study was to test the test-retest the reliability and construct validity of Qinematic™ in a healthy population, and to calculate the minimal clinical differences for the variables of interest. A further aim was to identify the discriminative validity of Qinematic™ in people with low-back pain (LBP).

Methods

We performed a test-retest reliability study (n = 37) with around 1 week between the occasions, a construct validity study (n = 30) in which Qinematic™ was tested against a 3D motion capture system, and a discriminative validity study, in which a group of people with LBP (n = 20) was compared to healthy controls (n = 17). We tested a large range of psychometric properties of 18 variables in three sections: posture (head and pelvic position, weight distribution), balance (sway area and velocity in single- and double-leg stance), and side-bending.

Results

The majority of the variables in the posture and balance sections, showed poor/fair reliability (ICC < 0.4) and poor/fair validity (Spearman <0.4), with significant differences between occasions, between Qinematic™ and the 3D–motion capture system. In the clinical study, Qinematic™ did not differ between people with LPB and healthy for these variables. For one variable, side-bending to the left, there was excellent reliability (ICC =0.898), excellent validity (r = 0.943), and Qinematic™ could differentiate between LPB and healthy individuals (p = 0.012).

Conclusion

This paper shows that a novel software program (Qinematic™) based on the Kinect camera for measuring balance, posture and side-bending has poor psychometric properties, indicating that the variables on balance and posture should not be used for monitoring individual changes over time or in research. Future research on the dynamic tasks of Qinematic™ is warranted.

Predictors of multidisciplinary rehabilitation outcomes in patients with chronic musculoskeletal pain: protocol for a systematic review and meta-analysis

BACKGROUND

Chronic musculoskeletal pain is a major public health problem. Early prediction for optimal treatment results has received growing attention, but there is presently a lack of evidence regarding what information such proactive management should be based on. This study protocol, therefore, presents our planned systematic review and meta-analysis on important predictive factors for health and work-related outcomes following multidisciplinary rehabilitation (MDR) in patients with chronic musculoskeletal pain.

METHODS

We aim to perform a synthesis of the available evidence together with a meta-analysis of published peer-reviewed original research that includes predictive factors preceding MDR. Included are prospective studies of adults with benign, chronic (> 3 months) musculoskeletal pain diagnoses who have taken part in MDR. In the studies, associations between personal and rehabilitation-based factors and the outcomes of interest are reported. Outcome domains are pain, physical functioning including health-related quality of life, and work ability with follow-ups of 6 months or more. We will use a broad, explorative approach to any presented predictive factors (demographic, symptoms-related, physical, psychosocial, work-related, and MDR-related) and these will be analyzed through (a) narrative synthesis for each outcome domain and (b) if sufficient studies are available, a quantitative synthesis in which variance-weighted pooled proportions will be computed using a random effects model for each outcome domain. The strength of the evidence will be evaluated using the Grading of Recommendations, Assessment, Development and Evaluation.

DISCUSSION

The strength of this systematic review is that it aims for a meta-analysis of prospective cohort or randomized controlled studies by performing an extensive search of multiple databases, using an explorative study approach to predictive factors, rather than building on single predictor impact on the outcome or on predefined hypotheses. In this way, an overview of factors central to MDR outcome can be made and will help strengthen the evidence base and inform a wide readership including health care practitioners and policymakers.

SYSTEMATIC REVIEW REGISTRATION

PROSPERO CRD42016025339.

Health risk appraisals in Swedish occupational health services

BACKGROUND: Health risk appraisals (HRAs) in occupational health services (OHS) in Sweden are very commonly used for health promotion issues, but not much research has explored the extent and nature of individual feedback that is provided.

OBJECTIVES: This study aimed to describe and explore HRAs in OHS regarding the content of the feedback in relation to the individual status and overall employee satisfaction.

METHODS: Feedback (evaluation and advice) and employee satisfaction with HRA were studied in employees that participated in health risk appraisals with a specific feedback session (HRA-F) (n = 272) and employees that participated in a single session (HRA-S) (n = 104). Associations between feedback and individual status concerning life style were assessed with Cohen’s kappa (k).

RESULTS: The employees received mainly information and advice for improvement on health and lifestyle issues (89–100%), while advice for improvement of working conditions was less common (15–59%). The feedback provided on life style was not based on individual status (k < 0.4), except for smoking and risky alcohol consumption (k > 0.55). A great majority of employees reported good overall satisfaction with their HRAs.

CONCLUSIONS: The evaluation and feedback given to employees after HRAs should be based more on HRA-results and advice could be focused more on work-related factors.

Predictors for persistent neck/shoulder pain, medical care-seeking due to neck/shoulder pain and sickness absence

Objective: To determine whether symptoms and clinical signs can predict persistent neck/shoulder pain, future medical care-seeking and sickness absence.

Design: A population-based cohort was followed prospectively over a 5—6 year period.

Setting: Subjects from the district of Norrtälje (Sweden).

Subjects: Subjects with self-rated neck/shoulder pain were included ( n = 1471).

Main measures: Cox regression analyses were used to test the predictive value of single and combinations of symptoms and clinical signs obtained with questionnaires and simple tests concerning persistent neck/shoulder pain, future medical care-seeking and sickness absence.

Results: Several symptoms and clinical signs were associated with the outcomes of interest: the relative risk (RR) for persistent neck/shoulder pain was 1.38 (95% confidence interval (CI) 1.14—1.52) for subjects with pain for over three months at baseline and concerning future medical care-seeking RR was 2.10 (95% CI 1.73—2.54) for subjects who had previously sought medical care. An episode of sickness absence during the year of enrolment increased the risk for future sickness absence (RR = 2.42, 95% CI 1.95—3.00). Having five or seven concurrent symptoms and clinical signs was common and more strongly associated with persistent pain (RR = 1.77, 95% CI 1.39 — 2.27) and future medical care-seeking (RR = 4.51, 95% CI 2.54—9.94), respectively, but not concerning sickness absence.

Conclusion: By simply counting the number of concurrent symptoms and clinical signs, it is possible to predict persistent neck/shoulder pain and future medical care-seeking, but not sickness absence.

Are job strain and sleep disturbances prognostic factors for neck/shoulder/arm pain? A cohort study of a general population of working age in Sweden

OBJECTIVE

To study whether job strain, that is, psychological job demands and decision latitude, and sleep disturbances among persons with occasional neck/shoulder/arm pain (NSAP) are prognostic factors for having experienced at least one episode of troublesome NSAP, and to determine whether sleep disturbances modify the association between job strain and troublesome NSAP.

DESIGN

Prospective cohort study.

SETTING

Stockholm, Sweden.

PARTICIPANTS

A population-based cohort of individuals with occasional NSAP (n=6979) who answered surveys in 2006 and 2010.

OUTCOME MEASURES

Report of at least one episode of troublesome NSAP in 2010.

RESULTS

The ORs for troublesome NSAP at follow-up were in individuals exposed to passive jobs 1.2 (95% CI 0.9 to 1.4); to active jobs 1.3 (95% CI 1.1 to 1.5); to high strain 1.5 (95% CI 1.0 to 2.4); to mild sleep disturbances 1.4 (95% CI 1.3 to 1.6) and to severe sleep disturbances 2.2 (95% CI 1.6 to 3.0). High strain and active jobs were associated with having experienced at least one episode of troublesome NSAP during the previous 6 months in persons with sleep disturbances, but not in individuals without sleep disturbances.

CONCLUSIONS

Our results indicate that high strain, active jobs and sleep disturbances are prognostic factors that should be taken into account when implementing preventive measures to minimise the risk of troublesome NSAP among people of working age. We suggest that sleep disturbances may modify the association between high strain and troublesome NSAP.

Reliability of the Fox-walk test in patients with rheumatoid arthritis

PURPOSE

The Fox-walk test is a new method used to estimate aerobic capacity outside a clinical environment, which may be useful in the implementation of daily health-enhancing physical activity. The aim of our study was to investigate the reliability of the test in people with rheumatoid arthritis (RA).

METHOD

Fifteen participants performed the Fox-walk test three times with weekly intervals. The intraclass correlation coefficient (ICC), the standard error of measurement (SEM) and the smallest detectable change (SDC) were used to estimate the reliability. General health perception, lower limb pain and fatigue were measured to determine their potential influence on the reliability.

RESULTS

There were no systematic differences between the three test occasions (p = 0.190) and the reliability was almost perfect (ICC = 0.982). None of the covariates influenced the reliability. The SEM was 0.999 ml/kg/min or 3.4% and the SDC was 2.769 ml/kg/min or 9.4%.

CONCLUSIONS

These findings demonstrate that the Fox-walk test is reliable in people with RA and enables differentiation between people with RA and monitoring progress. The validity of the test among people with RA is still to be determined.

IMPLICATIONS FOR REHABILITATION

• The Fox-walk test is a new method to estimate aerobic capacity and could be performed walking or running. • The test is self administered without expensive equipment and is available in 150 public places in Sweden and several other European countries. • The Fox-walk test is a reliable test for use among people with rheumatoid arthritis monitoring the progress of their physical activity.

The influence of work-related exposures on the prognosis of neck/shoulder pain

To determine associations between work-related exposures and the prognosis of self-reported neck/shoulder pain. This prospective cohort study was based on 803 working subjects who reported neck/shoulder pain at baseline. The proportion of subjects who 5-6 years later were symptom-free was calculated. Data concerning work-related biomechanical, psychosocial, and organizational exposures were collected at baseline. The Cox regression analyses were used to calculate the relative chances (RC) of being symptom-free at the end of the study for single exposures, and also for up to three simultaneous work-related exposures. Adjustments were made for sex and age. Only 36% of the subjects were symptom-free 5-6 years later. The relative chance for being symptom-free at the end of the study was 1.32 (95% CI = 0.99-1.74) for subjects who were exposed to sitting > or =75% of the working time and 1.53 (95% CI = 1.02-2.29) for subjects who were exposed to job strain, i.e., the combination of high demands and low decision latitude. The relative chance of being symptom-free at the end of the study was 0.61 (95% CI = 0.40-0.94) for subjects with at least two out of three simultaneous biomechanical exposures at work; manual handling, working with the hands above shoulder level, and working with vibrating tools. In a heterogeneous population with moderate nonspecific neck/shoulder pain, sedentary work enhanced the chance of being symptom-free 5-6 years later, whereas simultaneous exposures to at least two of manual handling, working with hands above shoulder level and working with vibrating tools were associated with a lower chance of being symptom-free at the end of the study. This could imply that subjects with neck/shoulder pain should avoid such simultaneous exposures.

The effect of ergonomic intervention on neck/shoulder and low back pain

The aim of this study was to examine the effect of two types of ergonomic intervention on pain and pain-related disability in the neck/shoulder and low back regions. A cohort of 492 subjects of various occupations with non-specific neck/shoulder or low back pain was followed over a five to six year period. The study subjects were classified into four intervention groups: no ergonomic intervention, educational worksite intervention, workplace intervention, and combined workplace and educational worksite intervention. The group with no ergonomic intervention was used as the reference group. The changes in pain intensity and pain-related disability from baseline to follow-up in each of the three groups with intervention were compared to the changes in the reference group. During the follow-up, 39% of the subjects had received ergonomic intervention. The average change in pain intensity and pain-related disability was smaller in the educational worksite intervention group than in the reference group. The average reduction of pain intensity and pain-related disability did not differ between the two other intervention groups and the reference group. Thus, for subjects still at work, ergonomic intervention seemed to be ineffective for reducing neck/shoulder and low back pain and pain-related disability.

Sickness absence and concurrent low back and neck-shoulder pain: results from the MUSIC-Norrtälje study

In Sweden, musculoskeletal disorders, in particular low back disorders (LBD) and neck-shoulder disorders (NSD) constitute by far the most common disorders, causing sick leave and early retirement. Studies that compare sickness absence in individuals with LBD and individuals with NSD are lacking. Moreover, it is likely that having concurrent complaints from the low back region and the neck-shoulder region could influence sickness absence. The purpose of the present study was to explore potential differences in sickness absence and in long-term sickness absence during a 5-year period, 1995-2001, among individuals with (1) solely LBD, (2) solely NSD, and (3) concurrent LBD and NSD. The present study was based on 817 subjects from the MUSIC-Norrtälje study, whom were working at baseline and whom at both baseline and follow-up reported LBD and/or NSD. Three groups were identified based on pain and pain-related disability at both baseline and follow-up: (1) solely LBD, (2) solely NSD, and (3) concurrent LBD and NSD. Subjects who did not give consistent answers at both the baseline and follow-up occasions were assigned a fourth group: (4) migrating LBD/NSD. Two outcomes were analysed: (1) prevalence of sickness absence, and (2) long-term sickness absence among those with sickness absence days. Logistic regression analysis was used to calculate odds ratios (OR) for sickness absence in the different disorder groups, taking into account confounding factors such as gender, age and other non-musculoskeletal-related disorders. In the group concurrent LBD and NSD, 59% had been sickness absent between baseline and follow up, compared to 42% in the group solely LBD, 41% in the group solely NSD, and 46% in the group migrating LBD/NSD. No difference in sickness absence was found between the group solely LBD compared to the group solely NSD [OR 0.65 (0.36-1.17)]. The adjusted OR for sickness absence in the group concurrent LBD and NSD compared to subjects with solely LBD or solely NSD was [OR 1.69 (1.14-2.51)]. The adjusted OR for having long-term sickness absence was 2.48 (95% CI = 1.32-4.66) for the group concurrent LBD and NSD. In the present study, having concurrent LBD and NSD were associated with a higher risk for sickness absence and also long-term sickness absence. This suggests that, when research on sickness absence and return to work after a period of LBD or NSD is performed, it is important to take into consideration any concurrent pain from the other spinal region. The study also implies that spinal co-morbidity is an important factor to be considered by clinicians and occupational health providers in planning treatment, or in prevention of these disorders.

Seeking Care for Neck/Shoulder Pain: A Prospective Study of Work-Related Risk Factors in a Healthy Population

This study estimated the 5-year cumulative incidence of neck/shoulder pain and identified work-related risk factors leading subjects to seek care for this problem. Four to six years after the case-referent MUSIC-Norrtälje Study, a postal questionnaire was sent to the referents of this study, and 81% responded. At baseline, 516 men and 697 women were assessed as to their work-related exposures. The 4- to 6-year cumulative incidence for seeking care for neck/shoulder pain was 29% for women and 18% for men. For men, moderately increased risks were found for manual handling, night work/shift work, hindrances at work, and solitary work. For men, the risk increased with an increasing number of risk indicators. No work-related risk factors were found for women, highlighting the difficulty of identifying risk factors in a general population.

Reliability of isokinetic supine bench press in healthy women using the Ariel Computerized Exercise System

The aim of this study was to assess reliability of the Ariel Computerized Exercise System (ACES) "multifunction exerciser". Twenty-three healthy women completed three sets, three repetitions each, of maximal isokinetic supine bench press at two different velocities, slow (10/s) and moderate (25/s). The following performance parameters were studied: peak and average force, peak and average power, and total work. The experiment was repeated for two days. Intraclass correlation coefficients (ICC[2,1]) varied between 0.947 and 0.755 at 10 degrees/s and between 0.861 and 0.654 at 25 degrees/s. The standard error of the measurement (SEM), the smallest detectable difference (SDD), and the coefficient of variation (CV) indicated that it is possible to achieve reliable and clinically relevant measurements with the ACES.