Participatory ergonomic intervention versus strength training on chronic pain and work disability in slaughterhouse workers: study protocol for a single-blind, randomized controlled trial

Mapping the conceptual structure of ergonomics, musculoskeletal disorders, treatment and return to work in manual jobs: A systematic review

BACKGROUND

Musculoskeletal disorders constitute one of the major health problems of workers exposed to manual work throughout the world. Nevertheless, there is no study that maps its conceptual structure based on a systematic methodology.

OBJECTIVE

To identify the conceptual structure of ergonomics, MSDs, treatment and return to work in manual jobs in the last 12 years by applying a systematic co-word network analysis methodology which describes the replicability of the search filters and emphasizes the rigor that has to be followed in the creation of the network.

METHODS

The search filter was customized for each bibliographic database, and followed the PRISMA 2020 flowchart for the screening process. For the creation of the network, the titles, abstracts, and keywords were used as the unit of analysis extracting the noun phrases of the first two units. In the normalization process, the terms of the search filter were deleted and their associated terms, and standardized the similar terms. Regarding the plotting of the network, Vosviewer was used applying the network settings based on content analysis.

RESULTS

The co-word network shows three communities: Ergonomic assessment and workplace intervention tools, factors related to rehabilitation and return to work, and physical and mental overload management. For each community, there is a framework that explains the relationship within terms.

CONCLUSION

This study is aligned with the replicability, robustness, and relevance recommendations in the implementation of rigorous scientometric studies. The occupational health community is encouraged to implement scientometric studies following a rigorous methodology and working in interdisciplinary team.

Attention to Progression Principles and Variables of Exercise Prescription in Workplace-Related Resistance Training Interventions: A Systematic Review of Controlled Trials

Background

The workplace is an important setting for adult health promotion including exercise training such as resistance training (RT). Since the reporting of exercise training interventions is generally inconsistent, the objective of this systematic review was to investigate the attention to principles of RT progression and variables of RT exercise prescription in workplace-related RT interventions.

Methods

A systematic literature search was conducted in the databases LIVIVO, PubMed, SPORTDiscus, and Web of Science (2000–2020). Controlled trials with apparently healthy “employees” and a main focus on RT were included. RT principles and variables were extracted and rated by two reviewers (reported, not reported, or unclear). Sum scores for each RT intervention and percentages regarding each principle and variable were calculated.

Results

Overall, 21 articles were included (18 primary studies, 3 protocols). Summarized narratively, the interventions showed different positive effects on strength- or performance-related and/or health- or complaint-related outcomes. The reporting of the RT principles and variables was varied [progressive overload: 94% of the studies, specificity: 78%, variation (periodization): 39%, muscle action: 94%, loading: 94%, volume; 67%, exercise selection: 89%, exercise order: 47%, rest periods between sets: 33%, rest periods between exercises: 27%, repetition velocity: 44%, and frequency: 100%].

Conclusion

Several key RT principles and variables were reported inconsistently, reducing reproducibility and pointing to the need for standardized RT intervention reporting in workplace-related interventions. Exercise science and workplace promotion should be further linked, since accurate reporting is a prerequisite for transferring robust findings into practice.

The Effects on Turkish Ice Cream Employees' Musculoskeletal Pain of Physical Activity and Ergonomy Programme in Workplace

ABSTRACTObjective. This study aimed to investigate the effects of physical activity and ergonomy programme (PAEIP) on employees' musculoskeletal pain. Methods. The sampling group included 120 employees met the criteria and were randomly assigned to the intervention group (N = 57) and the control group (N = 63). Visual Analog Scale (VAS), Nordic Musculoskeletal Survey, Rapid Upper Limb Assessment (RULA) were used for collecting data. Results. When pre-test and post-test pain scores of intervention group were compared, the average post-test scores were significantly lower in neck, shoulder, wrist and low back regions than the pre-test scores. When the intervention and control groups' RULA score compared, in the intervention group whereas proportion of employees found in "acceptable posture" level was 0 percent in pre-test, it was 5.3 percent in the post-test, and in the same group, proportion of employees in "further investigation and change may be needed" level was 31.6% in the pre-test, this rate increased to 61.4% in the post-test. Conclusion. As a result, PAEIP has been found effective in reducing the ergonomic risks associated with upper extremities and rate or intensity of musculoskeletal pain.

Lateral epicondylosis: A literature review to link pathology and tendon function to tissue-level treatment and ergonomic interventions

BACKGROUND

Common treatments for lateral epicondylosis (LE) focus on tissue healing. Ergonomic advice is suggested broadly, but recommendations based on biomechanical motion parameters associated with functional activities are rarely made. This review analyzes the role of body functions and activities in LE and integrates the findings to suggest motion parameters applicable to education and interventions relevant to activities and life roles for patients.

PURPOSE

This study examines LE pathology, tendon and muscle biomechanics, and population exposure outlining potentially hazardous activities and integrates those to provide motion parameters for ergonomic interventions to treat or prevent LE. A disease model is discussed to align treatment approaches to the stage of LE tendinopathy.

STUDY DESIGN

Integrative review METHODS: We conducted in-depth searches using PubMed, Medline, and government websites. All levels of evidence were included, and the framework for behavioral research from the National Institutes of Health was used to synthesize ergonomic research.

RESULTS

The review broadened the diagnosis of LE from a tendon ailment to one affecting the enthesis of the capitellum. It reinforced the continuum of severity to encompass degeneration as well as regeneration. Systematic reviews confirmed the availability of evidence for tissue-based treatments, but evidence of well-defined harm reducing occupational interventions was scattered amongst evidence levels. Integration of biomechanical studies and population information gave insight into types of potentially hazardous activities and provided a theoretical basis for limiting hazardous exposures to wrist extensor tendons by reducing force, compression, and shearing during functional activities.

CONCLUSIONS

These findings may broaden the first treatment approach from a passive, watchful waiting into an active exploration and reduction of at-risk activities and motions. Including the findings into education modules may provide patients with the knowledge to lastingly reduce potentially hazardous motions during their daily activities, and researchers to define parameters of ergonomic interventions.

Periodized resistance training for persistent non-specific low back pain: a mixed methods feasibility study

Background

We investigated the feasibility of a 16-week supervised heavy resistance training program with weekly undulating periodization for individuals with persistent non-specific low-back pain (LBP).

Methods

Twenty-five adults with persistent non-specific LBP participated in this mixed methods feasibility study. Participants trained a whole-body program consisting of squat, bench press, deadlift and pendlay row two times per week for 16 weeks. We assessed pain intensity, pain-related disability, pain self-efficacy and one-repetition maximum strength at baseline, 8 weeks and 16 weeks. Three focus group interviews were conducted at the end of the program. Linear mixed models were used to assess changes in outcomes, and the qualitative data was assessed using systematic text condensation.

Results

We observed clinically meaningful reductions in pain intensity after 8 and 16 weeks of training. The mean difference on the numeric pain rating scale (0–10) in the last 2 weeks from baseline to 8 weeks was 2.6 (95% CI: 1.8–3.6) and from baseline to 16 weeks 3.4 (95% CI: 2.5–4.4). In addition, there were improvements in pain-related disability (3.9, 95% CI: 2.3–5.5), pain self-efficacy (7.7, 95% CI: 5.4–10.1) and muscle strength. In the focus group interviews, participants talked about challenges regarding technique, the importance of supervision and the advantages of periodizing the training. Perceived benefits were improved pain, daily functioning, energy level and sleep, and changes in views on physical activity.

Conclusion

Periodized resistance training with weekly undulating periodization is a feasible training method for this group of individuals with persistent non-specific LBP. A randomized clinical trial should assess the efficacy of such an intervention.

Trial registration

clinicaltrials.gov/ Identifier – NCT04284982, Registered on February 24th 2020.

Workplace-Based Rehabilitation of Upper Limb Conditions: A Systematic Review

Purpose The objective of this systematic review was to identify, collate and analyse the current available evidence on the effectiveness of workplace-based rehabilitative interventions in workers with upper limb conditions on work performance, pain, absenteeism, productivity and other outcomes. Methods We searched Medline, Cochrane Library, Scopus, Web of Science, Academic Search Premier, Africa-Wide Information, CINAHL, OTSeeker and PEDro with search terms in four broad areas: upper limb, intervention, workplace and clinical trial (no date limits). Studies including neck pain only or musculoskeletal pain in other areas were not included. Results Initial search located 1071 articles, of which 80 were full text reviewed. Twenty-eight articles were included, reporting on various outcomes relating to a total of seventeen studies. Nine studies were of high methodological quality, seven of medium quality, and one of low quality. Studies were sorted into intervention categories: Ergonomic controls (n = 3), ergonomic training and workstation adjustments (n = 4), exercise and resistance training (n = 6), clinic-based versus workplace-based work hardening (n = 1), nurse case manager training (n = 1), physiotherapy versus Feldenkrais (n = 1), and ambulant myofeedback training (n = 1). The largest body of evidence supported workplace exercise programs, with positive effects for ergonomic training and workstation adjustments, and mixed effects for ergonomic controls. Ambulant myofeedback training had no effect. The remaining three categories had positive effects in the single study on each intervention. Conclusion While there is substantial evidence for workplace exercise programs, other workplace-based interventions require further high quality research. Systematic review registration PROSPERO CRD42017059708.

Test-retest reliability of knee extensors endurance test with elastic resistance

Background

Reliable clinical tests capable of measuring resistance are important tools for rehabilitation. One alternative that has recently increased in popularity is the use of elastic tubes, which stand out for being easy to handle, low cost, practical, and feasible.

Objective

Analyze the test-retest reliability of the knee extensors muscle fatigue resistance test (FRT) with elastic tubes.

Methods

A total of 116 healthy young males, aged between 18 and 30 years old, participated in the study. Participants performed three pre-test stages: orientation, load presentation, and familiarization with equipment, lasting two weeks. Subsequently, they performed the FRT on two occasions (test and retest), with an interval of seven days. The reliability analyzes were performed using the intraclass correlation coefficient (ICC) with 95% confidence interval and typical measurement error (TME), also expressed as coefficient of variation (CV%).

Results

The findings regarding the reliability of the test demonstrated satisfactory values (time: ICC = 0.66; 95%CI [0.50; 0.76]; CV(%) = 9.34; repetition: ICC = 0.61; 95%CI [0.46; 0.73], CV(%) = 13.66; rhythm: ICC = 0.52; 95%CI [0.35; 0.67], CV(%) = 10.29.

Conclusion

From the findings presented, it is concluded that the proposed clinical test with elastic tubes demonstrates evidence of acceptable values.

Incident CTS in a large pooled cohort study: associations obtained by a Job Exposure Matrix versus associations obtained from observed exposures

Background

There is growing use of a job exposure matrix (JEM) to provide exposure estimates in studies of work-related musculoskeletal disorders; few studies have examined the validity of such estimates, nor did compare associations obtained with a JEM with those obtained using other exposures.

Objective

This study estimated upper extremity exposures using a JEM derived from a publicly available data set (Occupational Network, O*NET), and compared exposure-disease associations for incident carpal tunnel syndrome (CTS) with those obtained using observed physical exposure measures in a large prospective study.

Methods

2393 workers from several industries were followed for up to 2.8 years (5.5 person-years). Standard Occupational Classification (SOC) codes were assigned to the job at enrolment. SOC codes linked to physical exposures for forceful hand exertion and repetitive activities were extracted from O*NET. We used multivariable Cox proportional hazards regression models to describe exposure-disease associations for incident CTS for individually observed physical exposures and JEM exposures from O*NET.

Results

Both exposure methods found associations between incident CTS and exposures of force and repetition, with evidence of dose–response. Observed associations were similar across the two methods, with somewhat wider CIs for HRs calculated using the JEM method.

Conclusion

Exposures estimated using a JEM provided similar exposure-disease associations for CTS when compared with associations obtained using the ‘gold standard’ method of individual observation. While JEMs have a number of limitations, in some studies they can provide useful exposure estimates in the absence of individual-level observed exposures.

Integrating participatory ergonomic management in non-weight-bearing exercise and progressive resistance exercise on self-care and functional ability in aged farmers with knee osteoarthritis: a clustered randomized controlled trial

Background

Ergonomic hazards are the most important cause of knee osteoarthritis (OA) in aged para rubber farmers. Ergonomic management comprising improvement of working conditions and muscle-strengthening exercise has been well documented in terms of workers' health benefit. However, those interventions were not adequate to sustain the advantage. Few studies have demonstrated the effect of integrating participatory ergonomic management (PEM) in non-weight-bearing exercise (NWE) and progressive resistance exercise (PRE), and none has focused on aged para rubber farmers with knee OA.

Purpose

This study investigated the effect of PEM-NWE, PEM-PRE, and standard treatment (ST) on self-care and functional ability in the aged population.

Materials and methods

A single-blinded, clustered randomized controlled trial was carried out. Participants (n=75) from three different communities in southern Thailand were randomly assigned to PEM-NWE, PEM-PRE, and ST. Self-care and functional ability (pain, stiffness, and physical function) were examined at baseline (B), during the intervention at Week 5 (W5), and after its completion at Week 9 (W9). Mean comparison of those outcomes over time was made using Generalized Linear Mixed Models (GLMMs).

Results

Compared to the standard treatment, the means of both groups, PEM-NWE and PEM-PRE, were significantly increased in self-care and functional ability. However, no significant difference between PEM-NWE and PEM-PRE was found.

Conclusion

Either or both interventions should be incorporated into nursing practice in order to promote occupational health and enhance quality of work life for Thai aged farmers. Further study on their cost-effectiveness is highly recommended.

Resistance training in addition to multidisciplinary rehabilitation for patients with chronic pain in the low back: Study protocol

INTRODUCTION

Chronic low back pain (LBP) is a major health problem worldwide. Multidisciplinary rehabilitation and exercise is recommended for the management of chronic LBP. However, there is a need to investigate effective exercise interventions that is available in clinics and as home-based training on a large scale. This article presents the design and rationale of the first randomized clinical trial investigating the effects of progressive resistance training with elastic bands in addition to multidisciplinary rehabilitation for patients with moderate to severe chronic LBP.

METHODS AND ANALYSIS

We aim to enroll 100 patients with chronic LBP referred to a specialized outpatient hospital clinic in Norway. Participants will be randomized equally to either; a) 3 tion including whole-body progressive resistance training using elastic bands - followed by home-based progressive resistance training for 9 weeks, or b) 3 weeks of multidisciplinary rehabilitation including general physical exercise - followed by home-based general physical exercise for 9 weeks. Questionnaires and strength tests will be collected at baseline, weeks 3 and 12, and at 6 and 12 months. The primary outcome is between-group changes in pain-related disability at week 12 assessed by the Oswestry disability index. Secondary outcomes include pain, work ability, work status, mental health, health-related quality of life, global rating of change, general health, and muscular strength and pain-related disability up to 12 months of follow-up.

DISCUSSION

This study will provide valuable information for clinicians working with patients with chronic LBP.

TRIAL REGISTRATION

ClinicalTrials.gov, number NCT02420236.

Psychosocial effects of workplace physical exercise among workers with chronic pain: Randomized controlled trial

While workplace physical exercise can help manage musculoskeletal disorders, less is known about psychosocial effects of such interventions. This aim of this study was to investigate the effect of workplace physical exercise on psychosocial factors among workers with chronic musculoskeletal pain.The trial design was a 2-armed parallel-group randomized controlled trial with allocation concealment. A total of 66 slaughterhouse workers (51 men and 15 women, mean age 45 years [standard deviation (SD) 10]) with upper limb chronic musculoskeletal pain were randomly allocated to group-based strength training (physical exercise group) or individual ergonomic training and education (reference group) for 10 weeks. Social climate was assessed with the General Nordic Questionnaire for Psychological and Social Factors at Work, and vitality and mental health were assessed with the 36-item Short Form Health Survey. All scales were converted to 0 to 100 (higher scores are better). Between-group differences from baseline to follow-up were determined using linear mixed models adjusted for workplace, age, gender, and baseline values of the outcome.Mean baseline scores of social climate, mental health, and vitality were 52.2 (SD 14.9), 79.5 (SD 13.7), and 53.9 (SD 19.7), respectively. Complete baseline and follow-up data were obtained from 30 and 31 from the physical exercise and reference groups, respectively. The between-group differences from baseline to follow-up between physical exercise and reference were 7.6 (95% CI 0.3 to 14.9), -2.3 (95% CI -10.3 to 5.8), and 10.1 (95% CI 0.6 to 19.5) for social climate, mental health, and vitality, respectively. For social climate and vitality, this corresponded to moderate effect sizes (Cohen d = 0.51 for both) in favor of physical exercise. There were no reported adverse events.In conclusion, workplace physical exercise performed together with colleagues improves social climate and vitality among workers with chronic musculoskeletal pain. Mental health remained unchanged.

Strength Training Improves Fatigue Resistance and Self-Rated Health in Workers with Chronic Pain: A Randomized Controlled Trial

Chronic musculoskeletal pain is widespread in the working population and leads to muscular fatigue, reduced work capacity, and fear of movement. While ergonomic intervention is the traditional approach to the problem, physical exercise may be an alternative strategy. This secondary analysis of a randomized controlled trial investigates the effect of strength training on muscular fatigue resistance and self-rated health among workers with chronic pain. Sixty-six slaughterhouse workers with chronic upper limb pain and work disability were randomly allocated to 10 weeks of strength training or usual care ergonomic training (control). At baseline and follow-up, participants performed a handgrip muscular fatigue test (time above 50% of maximal voluntary contraction force) with simultaneous recording of electromyography. Additionally, participants replied to a questionnaire regarding self-rated health and pain. Time to fatigue, muscle strength, hand/wrist pain, and self-rated health improved significantly more following strength training than usual care (all P < 0.05). Time to fatigue increased by 97% following strength training and this change was correlated to the reduction in fear avoidance (Spearman's rho = −0.40; P = 0.01). In conclusion, specific strength training improves muscular fatigue resistance and self-rated health and reduces pain of the hand/wrist in manual workers with chronic upper limb pain. This trial is registered with ClinicalTrials.gov NCT01671267.

An Analysis of Work-Related Musculoskeletal Disorders Among Butchers in Kano Metropolis, Nigeria

Background

Butchering is often associated with high rates of work-related musculoskeletal disorders (WRMSDs). However, published work on the prevalence of WRMSDs among butchers in Nigeria is scarce. This is important because meat processing practices differ across geographical and cultural locations. This study was therefore aimed at analyzing WRMSDs among butchers in Kano metropolis.

Methods

Sociodemographic and work-settings information was obtained from 102 male cattle butchers (age, 37.49 ± 11.68 years) through survey. Information on the prevalence and pattern of musculoskeletal disorders was obtained from the respondents using the Standardized Nordic Questionnaire. Additional information on health seeking practices was also obtained using a pro forma. Associations between the prevalence of WRMSDs and each of the sociodemographic data and work settings were explored using Chi-square analysis. The level of significance was set at p < 0.05.

Results

The 12-month and point prevalence rates of WRMSDs among butchers in this study were 88.2% and 74.5%, respectively. Whereas lower back complaints (66.7%) were the overall and lower body quadrant's most commonly reported WRMSDs among the butchers surveyed, wrist/hand complaints were the leading upper quadrant's (45.1%) most commonly reported WRMSDs among the respondents. There were significant associations between age and majority of WRMSDs in the body regions. Only 23.3% of the 90 individuals who had WRMSD visited the hospital to seek redress for their WRMSD.

Conclusion

The prevalence of WRMSDs is high among butchers in Kano Metropolis. Few individuals with WRMSD utilize healthcare facilities. Age is a major risk factor in this setting.

The Consequence of Combined Pain and Stress on Work Ability in Female Laboratory Technicians: A Cross-Sectional Study

Musculoskeletal pain and stress-related disorders are leading causes of impaired work ability, sickness absences and disability pensions. However, knowledge about the combined detrimental effect of pain and stress on work ability is lacking. This study investigates the association between pain in the neck-shoulders, perceived stress, and work ability. In a cross-sectional survey at a large pharmaceutical company in Denmark 473 female laboratory technicians replied to questions about stress (Perceived Stress Scale), musculoskeletal pain intensity (scale 0-10) of the neck and shoulders, and work ability (Work Ability Index). General linear models tested the association between variables. In the multi-adjusted model, stress (p < 0.001) and pain (p < 0.001) had independent main effects on the work ability index score, and there was no significant stress by pain interaction (p = 0.32). Work ability decreased gradually with both increased stress and pain. Workers with low stress and low pain had the highest Work Ability Index score (44.6 (95% CI 43.9-45.3)) and workers with high stress and high pain had the lowest score (32.7 (95% CI 30.6-34.9)). This cross-sectional study indicates that increased stress and musculoskeletal pain are independently associated with lower work ability in female laboratory technicians.

Stretch breaks in the work setting improve flexibility and grip strength and reduce musculoskeletal complaints

AbstractThis study investigated the effect of a stretch break program (SBP) on the flexibility, strength and musculoskeletal complaints of storage (SW) and administrative (AW) sector workers. Twenty-six male workers were randomly selected: 16 workers from the storage sector and ten workers from the administrative sector. We applied the Physical Activity Questionnaire and Musculoskeletal Questionnaire and evaluated flexibility and grip strength before and after 6 months of the SBP. The SPB decreased the SW group members' complaints of paresthesias and numbness in the upper body and total body. The SPB reduced the AW group members' complaints of paresthesias and numbness in the upper body. Furthermore, the SPB improved cervical, trunk and left shoulder flexibility in the SW group and improved cervical and shoulder flexibility and grip strength in the AW group. The SBP contribute to improve flexibility and musculoskeletal complaints in the regions that are affected by higher rates of work-related injuries.

Examining outcome of early physician specialist assessment in injured workers with shoulder complaints

Background

There is minimal research on demographics, type of injury and diagnosis of injured workers with shoulder problems. The purposes of this study were: 1) to document the demographics of patients with shoulder complaints referred to an Early Shoulder Physician Assessment (ESPA) Program and to describe the recommended management, and 2) to examine the relationship between patient characteristics and their subjective complaints of pain and functional difficulty.

Methods

This study involved a retrospective review of electronic files of injured workers mostly seen within the first 16 weeks of injury or recurrence. Measures of functional difficulty and pain were the Quick Disabilities of the Arm, Shoulder and Hand (QuickDASH) and Numeric Pain Scale (NPS).

Results

Files of 550 consecutive patients, 260 females (47%), 290 men (53%) were examined. The average age was 49 (SD = 11, range 22–77), with 28 (5%) patients being 65 years of age or older. Patients who were not working were the most disabled group based on Quick DASH (F = 49.93, p < 0.0001) and NPS (F = 10.24, p = 0.002). Patients who were working full time performing regular duties were the least disabled according to both measures, the QuickDASH (F = 10.24, p = 0.002) and NPS (F = 7.57, p = 0.006).

Patients waiting more than 16 weeks were slightly older (53 years of age vs. 49, p = 0.045) than those who met the criteria for early assessment with similar levels of pain and functional difficulty. Biceps pathology had the highest prevalence (37%). Full thickness tear had a prevalence of 14%. Instability, labral lesions and osteoarthritis of glenohumeral joint were uncommon conditions (3, 2 and 1% respectively). Fifty-five patients (10%) were surgical candidates and had higher scores on QuickDASH (F = 7.16, p = 0.008) and NPS (F = 4.24, p = 0.04) compared to those who did not require surgery.

Conclusions

This study provides information on characteristics and prevalence of important variables in injured workers with shoulder problems and highlights the impact of these characteristics on pain and disability.

Effect of individually tailored biopsychosocial workplace interventions on chronic musculoskeletal pain, stress and work ability among laboratory technicians: randomized controlled trial protocol

Background

Among laboratory technicians, the prevalence of neck and shoulder pain is widespread possibly due to typical daily work tasks such as pipetting, preparing vial samples for analysis, and data processing on a computer including mouse work - all tasks that require precision in motor control and may result in extended periods of time spent in static positions.

In populations characterized by intense chronic musculoskeletal pain and diagnosed conditions in conjunction with psycho-physiological symptoms such as stress-related pain and soreness and other disabling conditions, multifactorial approaches applying a combination of individually tailored physical and cognitive strategies targeting the areas most needed, may be an effective solution to the physical and mental health challenges.

The aim of this study is therefore to investigate the effect of an individually tailored biopsychosocial intervention strategy on musculoskeletal pain, stress and work disability in lab technicians with a history of musculoskeletal pain at a single worksite in Denmark.

Methods/design

In this single-blind two-armed parallel-group randomized controlled trial with allocation concealment, participants receive either an individualized multifactorial intervention or “usual care” for 10 weeks at the worksite. Inclusion criteria: 1) female laboratory technician (18-67 years of age) and 2) Pain intensity ≥ 3 (0-10 Visual Analogue Scale) lasting ≥3 months with a frequency of ≥ 3 days per week in one or more of the following regions: i) upper back i) low back iii) neck, iv) shoulder, v) elbow and/or vi) hand. Exclusion criteria: 1) life-threatening disease and 2) pregnancy. Stress, as measured by Cohen´s perceived stress questionnaire is not an inclusion criteria, thus participants can participate regardless of their stress level.

We will implement an individualized intervention addressing biopsychosocial elements of musculoskeletal pain with the following components; i) increasing physical capacity through strength- and motor control training; ii) lowering or preventing development of stress through mindfulness practice and learning de-catastrophizing pain management strategies through cognitive training.

The primary outcome at 10-week follow-up is the between-group difference in intensity of perceived musculoskeletal pain during the last week (average value of back, neck, shoulder, elbow and hand) assessed by questionnaire (modified visual analogue scale 0-10).

Discussion

This study will provide experimental evidence to guide workplace initiatives designed towards reducing chronic musculoskeletal pain and stress.

Trial registration number

ClinicalTrials.gov NCT02047669.

Electronic supplementary material

The online version of this article (doi:10.1186/1471-2474-15-444) contains supplementary material, which is available to authorized users.

Preventive occupational health interventions in the meat processing industry in upper-middle and high-income countries: a systematic review on their effectiveness

OBJECTIVE

To investigate the effectiveness of occupational health interventions in the meat processing industry on work and health-related outcomes.

METHODS

A systematic literature review was performed. PubMed, Embase, and The Cochrane Library were searched. Studies were included when they reported on an intervention among employees in the meat processing industry and with outcomes related to work or health. Studies were assessed on risk of bias, and data were synthesized by type of intervention.

RESULTS

A total of 13 articles reporting on two randomized controlled trials and nine non-randomized intervention studies were retrieved. Studies were categorized into three topics: ergonomics programs, skin protection, and Q fever vaccination. All studies had high risk of bias. Based on four studies, there was limited evidence for workplace health and safety programs showing reductions in musculoskeletal injury severity, reduction of lost work days, and reduction of costs and claims for several musculoskeletal disorders. There was limited evidence for added rest breaks resulting in improved productivity at the end of a workday and in reductions of perceived discomfort in various body regions at the end of the workday. One study on skin protection showed reductions of eczema prevalence, although evidence was moderate. Based on four studies, there was high-quality evidence for strong effectiveness of Q fever vaccination.

CONCLUSION

This review presents evidence for the effectiveness of a variety of workplace interventions. There was limited evidence for effectiveness of ergonomic interventions, moderate evidence of a skin protection intervention, and strong evidence for Q fever vaccination.

Conservative interventions for treating work-related complaints of the arm, neck or shoulder in adults

BACKGROUND

Work-related upper limb disorder (WRULD), repetitive strain injury (RSI), occupational overuse syndrome (OOS) and work-related complaints of the arm, neck or shoulder (CANS) are the most frequently used umbrella terms for disorders that develop as a result of repetitive movements, awkward postures and impact of external forces such as those associated with operating vibrating tools. Work-related CANS, which is the term we use in this review, severely hampers the working population.

OBJECTIVES

To assess the effects of conservative interventions for work-related complaints of the arm, neck or shoulder (CANS) in adults on pain, function and work-related outcomes.

SEARCH METHODS

We searched the Cochrane Central Register of Controlled Trials (The Cochrane Library, 31 May 2013), MEDLINE (1950 to 31 May 2013), EMBASE (1988 to 31 May 2013), CINAHL (1982 to 31 May 2013), AMED (1985 to 31 May 2013), PsycINFO (1806 to 31 May 2013), the Physiotherapy Evidence Database (PEDro; inception to 31 May 2013) and the Occupational Therapy Systematic Evaluation of Evidence Database (OTseeker; inception to 31 May 2013). We did not apply any language restrictions.

SELECTION CRITERIA

We included randomised controlled trials (RCTs) and quasi-randomised controlled trials evaluating conservative interventions for work-related complaints of the arm, neck or shoulder in adults. We excluded trials undertaken to test injections and surgery. We included studies that evaluated effects on pain, functional status or work ability.

DATA COLLECTION AND ANALYSIS

Two review authors independently selected trials for inclusion, extracted data and assessed risk of bias of the included studies. When studies were sufficiently similar, we performed statistical pooling of reported results.

MAIN RESULTS

We included 44 studies (62 publications) with 6,580 participants that evaluated 25 different interventions. We categorised these interventions according to their working mechanisms into exercises, ergonomics, behavioural and other interventions.Overall, we judged 35 studies as having a high risk of bias mainly because of an unknown randomisation procedure, lack of a concealed allocation procedure, unblinded trial participants or lack of an intention-to-treat analysis.We found very low-quality evidence showing that exercises did not improve pain in comparison with no treatment (five studies, standardised mean difference (SMD) -0.52, 95% confidence interval (CI) -1.08 to 0.03), or minor intervention controls (three studies, SMD -0.25, 95% CI -0.87 to 0.37) or when provided as additional treatment (two studies, inconsistent results) at short-term follow-up or at long-term follow-up. Results were similar for recovery, disability and sick leave. Specific exercises led to increased pain at short-term follow-up when compared with general exercises (four studies, SMD 0.45, 95% CI 0.14 to 0.75)We found very low-quality evidence indicating that ergonomic interventions did not lead to a decrease in pain when compared with no intervention at short-term follow-up (three studies, SMD -0.07, 95% CI -0.36 to 0.22) but did decrease pain at long-term follow-up (four studies, SMD -0.76, 95% CI -1.35 to -0.16). There was no effect on disability but sick leave decreased in two studies (risk ratio (RR) 0.48, 95% CI 0.32 to 0.76). None of the ergonomic interventions was more beneficial for any outcome measures when compared with another treatment or with no treatment or with placebo.Behavioural interventions had inconsistent effects on pain and disability, with some subgroups showing benefit and others showing no significant improvement when compared with no treatment, minor intervention controls or other behavioural interventions.In the eight studies that evaluated various other interventions, there was no evidence of a clear beneficial effect of any of the interventions provided.

AUTHORS' CONCLUSIONS

We found very low-quality evidence indicating that pain, recovery, disability and sick leave are similar after exercises when compared with no treatment, with minor intervention controls or with exercises provided as additional treatment to people with work-related complaints of the arm, neck or shoulder. Low-quality evidence also showed that ergonomic interventions did not decrease pain at short-term follow-up but did decrease pain at long-term follow-up. There was no evidence of an effect on other outcomes. For behavioural and other interventions, there was no evidence of a consistent effect on any of the outcomes.Studies are needed that include more participants, that are clear about the diagnosis of work-relatedness and that report findings according to current guidelines.

Test-retest repeatability of strength capacity, aerobic power and pericranial tenderness of neck and shoulder muscles in children - relevant for tension-type headache

Background

Frequent or chronic tension-type headache in children is a prevalent and debilitating condition for the child, often leading to medication overuse. To explore the relationship between physical factors and tension-type headache in children, the quality of repeated measures was examined. The aim of the present study was to determine the test-retest repeatability of parameters determining isometric neck and shoulder strength and stability, aerobic power, and pericranial tenderness in children.

Methods

Twenty-five healthy children, 9 to 18 years of age, participated in test-retest procedures within a 1-week interval. A computerized padded force transducer was used for testing. The tests included the isometric maximal voluntary contraction and force steadiness of neck flexion and extension, and the isometric maximal voluntary contraction and rate of force of the dominant shoulder. Pericranial tenderness was recorded by means of standardized manual palpation, and a submaximal cycle ergometer test predicted maximal oxygen uptake (VO₂ max). The measurements were evaluated in steps, using the intraclass correlation coefficient (ICC); changes in the mean between the two test occasions; the levels of agreement, visualized in Bland-Altman Plots; and by quantifying the variability.

Results

The results showed an acceptable test-retest repeatability of isometric maximal voluntary contraction (ICC 0.90–0.97). The force steadiness measurements revealed a trend of systematic changes in the direction of neck flexion and need further examination in both healthy and ill children. The rate of force development, Total Tenderness Score, and prediction of VO₂ max showed repeatability, with ICC 0.80–0.87.

Conclusion

The measurements of strength capacity, aerobic power, and tenderness provide acceptable repeatability, suitable for research in children.

The effect of double versus single oscillating exercise devices on trunk and limb muscle activation

PURPOSE/BACKGROUND

Proper strengthening of the core and upper extremities is important for muscular health, performance, and rehabilitation. Exercise devices have been developed that attempt to disrupt the center of gravity in order to activate the trunk stabilizing muscles. The objective of this study was to analyze the trunk and shoulder girdle muscle activation with double and single oscillating exercise devices (DOD and SOD respectively) in various planes.

METHODS

TWELVE MALE SUBJECTS PERFORMED THREE INTERVENTIONS USING BOTH DEVICES UNDER RANDOMIZED CONDITIONS: single-handed vertical orientation of DOD and SOD to produce 1) medio-lateral oscillation in the frontal plane 2) dorso-ventral oscillation in the sagittal plane and 3) single-handed horizontal orientation for superior and inferior oscillation in the transverse plane. Electromyographic (EMG) activity during the interventions of the anterior deltoid, triceps brachii, biceps brachii, forearm flexors as well as lower abdominal and back stabilizer muscles was collected, and were normalized to maximal voluntary contractions. A two way repeated measures ANOVA (2x3) was conducted to assess the influence of the devices and movement planes on muscle activation.

RESULTS

The DOD provided 35.9%, 40.8%, and 52.3% greater anterior deltoid, transverse abdominus (TA)/internal oblique (IO) and lumbo-sacral erector spinae (LSES) activation than did the SOD respectively. Effect size calculations revealed that these differences were of moderate to large magnitude (0.86, 0.48, and 0.61 respectively). There were no significant differences in muscular activation achieved between devices for the triceps brachii, biceps brachii and forearm flexor muscles. Exercise in the transverse plane resulted in 30.5%, 29.5%, and 19.5% greater activation than the sagittal and 21.8%, 17.2%, and 26.3% greater activation than the frontal plane for the anterior deltoid, TA/IO and LSES respectively.

CONCLUSIONS

A DOD demonstrated greater muscular activity for trunk and shoulder muscle activation but does not provide an advantage for limb activation. Overall, oscillating the devices in the transverse plane provided greater muscular activation of the anterior deltoid, TA/IO and LSES than use of the devices during frontal or sagittal plane movements.

LEVEL OF EVIDENCE

2c: Outcomes research.