Musculoskeletal disorders of the neck and shoulders in female sewing machine operators: prevalence, incidence, and prognosis

Dry needling, trigger point electroacupuncture and motor point electroacupuncture for the treatment of myofascial pain syndrome involving the trapezius: a randomised clinical trial

OBJECTIVE

The objective of this study was to compare trigger point (TrP) dry needling, TrP electroacupuncture and motor point electroacupuncture of the trapezius muscle for the treatment of myofascial pain syndrome (MPS).

METHODS

This randomised clinical trial included 90 patients divided into three groups. Group 1 was treated with dry needling of TrPs, group 2 with intramuscular electrical stimulation of TrPs, and group 3 with electroacupuncture of motor points and/or the spinal accessory nerve. Each group received seven treatment sessions. The outcomes were the pain score measured by visual analogue scale (VAS) and quality of life evaluated by the 12-item short form (SF-12) health questionnaire. We compared the pain outcome over serial time points using growth curve analysis methods.

RESULTS

Participants in the three groups experienced significant improvements in pain scores over time. The average pain level of participants in group 3 across the repeated assessments was 0.98 units lower than in group 1 (mean difference (95% confidence interval (CI) = 1.74-0.23)), p = 0.012). There were no significant differences in pain scores between participants in groups 1 and 2, and there were no significant differences in quality of life across the three groups at the end of the treatment period.

CONCLUSION

Our results provide evidence that electrical stimulation of motor points and/or of the spinal accessory nerve may be superior in terms of pain relief (but not quality of life) to dry needling and possibly electrical stimulation of trigger points for the management of MPS involving the trapezius.

TRIAL REGISTRATION NUMBER

TRIAL-RBR-43R7RF (Brazilian Clinical Trials Registry).

Scoping review and interpretation of myofascial pain/fibromyalgia syndrome: An attempt to assemble a medical puzzle

BACKGROUND

Myofascial Pain Syndrome (MPS) is a common, overlooked, and underdiagnosed condition and has significant burden. MPS is often dismissed by clinicians while patients remain in pain for years. MPS can evolve into fibromyalgia, however, effective treatments for both are lacking due to absence of a clear mechanism. Many studies focus on central sensitization. Therefore, the purpose of this scoping review is to systematically search cross-disciplinary empirical studies of MPS, focusing on mechanical aspects, and suggest an organic mechanism explaining how it might evolve into fibromyalgia. Hopefully, it will advance our understanding of this disease.

METHODS

Systematically searched multiple phrases in MEDLINE, EMBASE, COCHRANE, PEDro, and medRxiv, majority with no time limit. Inclusion/exclusion based on title and abstract, then full text inspection. Additional literature added on relevant side topics. Review follows PRISMA-ScR guidelines. PROSPERO yet to adapt registration for scoping reviews.

FINDINGS

799 records included. Fascia can adapt to various states by reversibly changing biomechanical and physical properties. Trigger points, tension, and pain are a hallmark of MPS. Myofibroblasts play a role in sustained myofascial tension. Tension can propagate in fascia, possibly supporting a tensegrity framework. Movement and mechanical interventions treat and prevent MPS, while living sedentarily predisposes to MPS and recurrence.

CONCLUSIONS

MPS can be seen as a pathological state of imbalance in a natural process; manifesting from the inherent properties of the fascia, triggered by a disrupted biomechanical interplay. MPS might evolve into fibromyalgia through deranged myofibroblasts in connective tissue ("fascial armoring"). Movement is an underemployed requisite in modern lifestyle. Lifestyle is linked to pain and suffering. The mechanism of needling is suggested to be more mechanical than currently thought. A "global percutaneous needle fasciotomy" that respects tensegrity principles may treat MPS/fibromyalgia more effectively. "Functional-somatic syndromes" can be seen as one entity (myofibroblast-generated-tensegrity-tension), sharing a common rheuma-psycho-neurological mechanism.

Prevalence and incidence of work-related musculoskeletal disorders in secondary industries of 21st century Europe: a systematic review and meta-analysis

OBJECTIVE

Over the course of the twenty-first century, work-related musculoskeletal disorders are still persisting among blue collar workers. At present, no epidemiological overview exists. Therefore, a systematic review and meta-analysis was performed on the epidemiology of work-related musculoskeletal disorders (WMSD) within Europe's secondary industries.

METHODS

Five databases were screened, yielding 34 studies for the qualitative analysis and 17 for the quantitative analysis. Twelve subgroups of WMSDs were obtained for the meta-analysis by means of predefined inclusion criteria: back (overall), upper back, lower back, neck, shoulder, neck/shoulder, elbow, wrist/hand, leg (overall), hip, knee, and ankle/feet.

RESULTS

The most prevalent WMSDs were located at the back (overall), shoulder/neck, neck, shoulder, lower back and wrist WMSDs with mean 12-month prevalence values of 60, 54, 51, 50, 47, and 42%, respectively. The food industry was in the majority of subgroups the most prominent researched sector and was frequently associated with high prevalence values of WMSDs. Incidence ratios of upper limb WMSDs ranged between 0.04 and 0.26. Incidence ratios could not be calculated for other anatomical regions due to the lack of sufficient articles.

CONCLUSION

WMSDs are still highly present among blue collar workers. Relatively high prevalence values and low incidence ratios indicate a limited onset of WMSDs with however long-term complaints.

Ultrasound-guided interventional procedures for myofascial trigger points: a systematic review

Myofascial pain syndrome (MPS) is characterized by the presence of clinically detected myofascial trigger points (MTrPs). Diagnostic ultrasound (US) has been proposed as a method to strengthen the reliability of MTrP localization, thus potentially improving the efficacy and safety profile of interventional procedures. The objective is to evaluate the benefit and safety profile of any US-guided interventional procedure for MPS. Medline, Embase, PubMed, the Allied and Complementary Medicine Database (AMED), and Web of Science were systematically searched from their inception to May 2020 for any randomized controlled trial that evaluated treatment benefit and safety of any US-guided interventional procedure for MPS. The primary outcome of interest was pain severity. Additional outcomes of interest were function and adverse effects. The risk of bias was assessed using the Risk of Bias V.2.0 tool. eleven studies met all inclusion and exclusion criteria. Two studies (n=174) with a high risk of bias revealed some evidence supporting US guidance over blinded interventions for improvement in pain and function. Eight studies (n=483) with varying risks of bias were of head-to-head comparisons of different US modalities. These studies revealed that US-guided local anesthetic injections were inferior to US-guided pulse radiofrequency and US-guided dry needling (DN). US-guided DN was also found to be superior to US-guided platelet-rich-plasma injections but inferior to US-guided miniscalpel. Meanwhile, one study (n=21) with some concerns of bias found that US-guided local anesthetic injections were superior to non-steroidal anti-inflammatory drugs for pain outcomes and fewer adverse events. All US-guided procedures resulted in zero or minimal self-limited adverse events. Issues with clinical relevance, limited sample sizes, and small point estimates warrant more high-quality research to better characterize the possible value of US-guided injections.

The effect of dry needling on gastrocnemius muscle stiffness and strength in participants with latent trigger points

Abnormal muscle stiffness is a potential complication after injury and identifying interventions that modify muscle stiffness may be useful to promote recovery. The purpose of this study was to identify the short-term effects of dry needling (DN) on resting and contracted gastrocnemius muscle stiffness and strength of the triceps surae in individuals with latent myofascial trigger points (MTrPs). In this randomized controlled trial, 52 individuals received two DN treatment sessions to latent MTrPs and 50 individuals received two sham needling sessions. Resting and contracted muscle stiffness were assessed both at the treatment site and a standardized central site in the medial gastrocnemius head immediately post-treatment and one week after the last session. There were significant group by time interactions for resting muscle stiffness at the site of the MTrP (p = .03), but not at the central site (p = .29). Post-needling between group comparison indicated that the DN group had significantly lower resting muscle stiffness at the site of the MTrP than the sham group after adjusting for baseline differences. There were no significant between group differences in contracted muscle stiffness or muscle strength. Identifying strategies that can reduce aberrant muscle stiffness may help to guide management of individuals with neuromuscular pain-related conditions. Level of evidence: Therapy, level 2.

A flexible ergonomic redesign of the sewing machine workstation

Purpose

The apparel industry is a labor-intensive industry, which depends mainly on the performance of the worker. The purpose of this study is to present an ergonomic redesign of the sewing machine workstation, with different sewing table heights and inclination angles, based on the operator’s anthropometric data.

Design/methodology/approach

A flexible ergonomic sewing table has been designed, four main workstation-setting factors were studied; sewing desk inclination angles – X_1, height – X_2, sewing machine type – X_3 and operator’s body mass index (BMI) – X_4, with three levels for each factor, except sewing machine type, which only has two levels. The study was undertaken to specify the limitations and advantages of each combination tested. Different measurement techniques were used; subjective information, production rates – P, working postures (head, neck and trunk inclination angles in the kinematic stage) were measured.

Findings

Sewing operators’ sitting posture angles in the kinematic stage were affected more or less by their anthropometric measurements and the type of sewing machine. These two factors should be taken into consideration when ergonomically redesigning the sewing machine workstation.

Practical implications

A new ergonomically redesigned sewing machine table can be incorporated into garment factories, taking into consideration the BMI of the operators to improve their productivity and reduce musculoskeletal disorder complaints due to incorrect operators’ posture.

Originality/value

An important correlation was found between the sewing operator’s anthropometric body measurement – BMI and the type of sewing machine (with significant R^2 = 0.8385 and 0.9764 with both the head and neck inclination angles O_H, O_N, respectively).

ANALISIS TINGKAT KELELAHAN SUBYEKTIF BERDASARKAN SIKAP KERJA PENJAHIT DI INDUSTRI KONVEKSI

Work manner affects health safety and environment in the work station. It also affects workers’ fatigue which can reduce their performance resulting from the excessive of physical and mental at the working environment. The purpose of this study was to analyze the relationship between the tailor work attitude with the incidence of work fatigue on workers in the Ramli convection industry that engaged in fashion. The research was a descriptive by using the assessment of RULA model that targets of body posture of the workers in the Convection Industry. This research aimed to estimate the risk accident of skeletal muscle disorder and to assess work attitude which having pain, fatigue and musculoskeletal disorder by using RULA Model. The improvement of work attitude with changing of work position by standing up and sitting down, not slouching and not bending, and the improvement of work station such as making the ergonomic of the tailors’ chair. The results showed a strong correlation between fatigue with age (r = 0.711), work period (r = 0.854), intermediate relationship with gender (r = 0.439), work attitude (r = 0.416), and the working environment (r = 0.419). The result showed a weak correlation between fatigue with work station (r = 0.448). The conclusion is workers who have a high risk of work attitude experience a higher level of fatigue.Keywords: work attitude, work fatigue, work station

Blue-collar work and women's health: A systematic review of the evidence from 1990 to 2015

Despite the implications of gender and sex differences for health risks associated with blue-collar work, adverse health outcomes among blue-collar workers has been most frequently studied among men. The present study provides a "state-of-the-field" systematic review of the empiric evidence published on blue-collar women's health. We systematically reviewed literature related to the health of blue-collar women published between January 1, 1990 and December 31, 2015. We limited our review to peer-reviewed studies published in the English language on the health or health behaviors of women who were presently working or had previously worked in a blue-collar job. Studies were eligible for inclusion regardless of the number, age, or geographic region of blue-collar women in the study sample. We retained 177 studies that considered a wide range of health outcomes in study populations from 40 different countries. Overall, these studies suggested inferior health among female blue-collar workers as compared with either blue-collar males or other women. However, we noted several methodological limitations in addition to heterogeneity in study context and design, which inhibited comparison of results across publications. Methodological limitations of the extant literature, alongside the rapidly changing nature of women in the workplace, motivate further study on the health of blue-collar women. Efforts to identify specific mechanisms by which blue-collar work predisposes women to adverse health may be particularly valuable in informing future workplace-based and policy-level interventions.

The impact of a change in work posture from seated to stand-up on work-related musculoskeletal disorders among sewing-machine operators

BACKGROUND

Work-related postural change could lead to improved musculoskeletal health.

METHOD(S)

In a quantitative, retrospective, longitudinal study, data of work-related musculoskeletal disorders of 123 sewing-machine operators were captured for 4.5 years, and analysed using Poisson regression.

RESULTS

Stand-up work posture (SUWP) reduced the incidence for spinal disorders (SD) to 0.29 fold the incidence for sitting work posture (SWP) (P < 0.001). Morbid obesity had significantly increased (P = 0.04) incidence of upper limb disorders (ULD), 3.35 times that of normal body mass index (BMI) (regardless of work posture). SUWP was associated with increased IRR (1.49) for lower limb disorders (LLD). LLDs were associated with obesity (overweight (IRR = 2.58; P = 0.08), obese (IRR = 2.45; P = 0.09), and morbidly obese (IRR = 6.24; P = 0.001)).

CONCLUSIONS

The protective benefit of the SUWP was statistically significant for SD incidence. Owing to high mean BMI, SUWP had a negative impact on the incidence of LLDs for the first 2 months.

Risk of subacromial shoulder disorder in airport baggage handlers: combining duration and intensity of musculoskeletal shoulder loads

Musculoskeletal shoulder load among baggage handlers measured by combining duration and intensity based on biomechanical and epidemiological information may be a stronger predictor of subacromial shoulder disorders than baggage handler seniority. In 2012, a cohort of baggage handlers employed at Copenhagen Airport in 1990-2012, and a cohort of unskilled otherwise employed men answered a survey. Self-reported information on work tasks during employment in the airport in combination with work task specific biomechanically modelled forces in the shoulder joint was used to estimate shoulder load. Exposure measures were accumulated shoulder abduction moment, accumulated shoulder compression force, accumulated supraspinatus force and baggage handler seniority. The outcome was subacromial shoulder disorder registered in the Danish National Patient Register. When analyses were adjusted by all confounders except age, exposure variables showed close to significant associations with subacromial shoulder disorder. Results could not confirm our hypothesis that combined information on work task duration and shoulder load intensity was stronger associated with subacromial shoulder disorder than seniority. Practitioner Summary: In this study we sought to identify if the exposure to work-related musculoskeletal shoulder loading including duration and intensity among baggage handlers was associated with subacromial shoulder disorder. We found that there was an association but this was not stronger than that between baggage handler seniority and subacromial shoulder disorder.

Comparing Trigger Point Dry Needling and Manual Pressure Technique for the Management of Myofascial Neck/Shoulder Pain: A Randomized Clinical Trial

OBJECTIVE

The aim of this study was to investigate short-term and long-term treatment effects of dry needling (DN) and manual pressure (MP) technique with the primary goal of determining if DN has better effects on disability, pain, and muscle characteristics in treating myofascial neck/shoulder pain in women.

METHODS

In this randomized clinical trial, 42 female office workers with myofascial neck/shoulder pain were randomly allocated to either a DN or MP group and received 4 treatments. They were evaluated with the Neck Disability Index, general numeric rating scale, pressure pain threshold, and muscle characteristics before and after treatment. For each outcome parameter, a linear mixed-model analysis was applied to reveal group-by-time interaction effects or main effects for the factor "time."

RESULTS

No significant differences were found between DN and MP. In both groups, significant improvement in the Neck Disability Index was observed after 4 treatments and 3 months (P < .001); the general numerical rating scale also significantly decreased after 3 months. After the 4-week treatment program, there was a significant improvement in pain pressure threshold, muscle elasticity, and stiffness.

CONCLUSION

Both treatment techniques lead to short-term and long-term treatment effects. Dry needling was found to be no more effective than MP in the treatment of myofascial neck/shoulder pain.

Neck-Shoulder Pain and Work Status among Former Sewing Machine Operators: A 14-year Follow-up Study

Purpose A total of 243 Danish female sewing machine operators lost their jobs in 1996 because of outsourcing. The aim was to investigate the employment status during follow-up from 1996 to 2008, and to estimate to what extent former neck-shoulder pain had an impact on later work participation. Methods Assessment of neck-shoulder pain was based on questionnaires completed in 1994. The Danish Register-Based Evaluation of Marginalization (DREAM) register was used to describe employment status during the follow-up period. Register data were explored by sequence analyses and graphics, and the association between neck-shoulder pain and work participation was analyzed by logistic regression analysis. Results In all, 987 working years were lost during follow-up, and a sequence index plot revealed interrupted and heterogeneous courses of incomes. The odds ratio between neck and shoulder pain and a work participation score less than 75% was 1.49 (95% CI 0.84-2.67). Conclusions After outsourcing of the textile industry, the former sewing machine operators had decreased work participation and frequent transitions between different income types. Previous neck-shoulder pain tended to be associated with poor work participation. The results suggest that increased attention should be to given to dismissed workers from other industries that become outsourced, especially unskilled workers with similar work-related health limitations. Additionally, we concluded that time-to-event measures in research involving employment status are insufficient because of the many transitions that take place in working life.

The Current Working Conditions in Ugandan Apparel Assembly Plants

BACKGROUND

The present rapid shift of industrialization from developed to developing countries requires developing countries to understand issues related to work organization, management, and working conditions. There are many factors slackening production, of which working conditions is part. A complete inquiry into the workers' working conditions can enable managements to reduce risks in the workplaces and improve productivity. Understanding and awareness of the benefits of workplace research and a probe into the working conditions in the Ugandan apparel assembly plants are urgently required.

METHODS

A total of 103 (70 women and 33 men) workers from five different plants were interviewed. Together with the top management of various plants, questionnaires about the workers' opinions of their physical working conditions were prepared. Data was collected using two methods: (1) questionnaire; and (2) observation of the workers during their work.

RESULTS

The results indicated that poor plant working conditions were mainly contributed by the workers' social factors and the management policies.

CONCLUSION

The government, together with the management, should work to improve the working conditions in the apparel assembly plants, as it greatly affects both.

Risk factors for episodic neck pain in workers: a 5-year prospective study of a general working population

PURPOSE

Development of neck pain (NP) in workers has a multifactorial etiology and depends on both individual and workplace factors. The aim of this study was to investigate risk factors for episodic NP in a large diverse sample of active workers.

METHODS

A prospective study based on the surveillance program implemented by the French Public Health Agency in the Loire Valley region. Between 2002 and 2005, 3710 workers were included. Between 2007 and 2010, 2332 workers responded to a follow-up questionnaire which assessed: (1) musculoskeletal symptoms (Nordic questionnaire) and (2) individual and work-related risk factors. Associations between episodic NP in 2007 (i.e., free subjects at baseline and who suffered at least 8 days during the preceding 12 months) and individual and work-related risk factors at baseline were studied using logistic regression modeling, stratified by sex.

RESULTS

Among the 1510 workers (914 men, 596 women) still active at follow-up, 10.4% (8.4-12.4) of men and 14.6% (11.8-17.4) of women declared episodic NP. Among men, work pace dependence of guests or permanent hierarchical controls were risk factors of NP [OR = 1.8 (1.1-2.8) and OR = 2.1 (1.3-3.3), respectively]. Among women, the combination of sustained/repeated arm abduction with high physical perceived exertion was the strongest risk factor for NP [OR = 3.5 (1.7-7.2)]; age and paced work were also predictors for NP in women.

CONCLUSIONS

NP results from complex relationships between individual and work-related variables. High physical workload, awkward postures, and poor organizational environment together with age differently predicted episodic NP according to the sex.

Long-term prognosis for neck-shoulder pain and disorders: a 14-year follow-up study

OBJECTIVES

The long-term prognosis for neck-shoulder pain and disorders and the impact of shoulder exposure among former sewing machine operators were investigated in a 14-year follow-up study.

METHODS

Information on neck-shoulder pain and disorders was collected by questionnaire and clinical examination at baseline in 243 female sewing machine operators and by questionnaire 14 years later. During follow-up, information on comorbidity and job exposures was obtained from registers and by linking register-based D-ISCO 88 codes with a job exposure matrix. Logistic regression analyses were performed to examine associations between neck-shoulder pain and disorders at baseline and neck-shoulder pain and physical functioning at follow-up.

RESULTS

We found an association between neck-shoulder disorders at baseline and neck-shoulder pain at follow-up (OR 5.9;95% CI 1.9 to 17.7), and between neck-shoulder pain at baseline and neck-shoulder pain at follow-up (OR 8.2;95% CI 3.5 to 19.2). Associations between neck-shoulder disorders and pain at baseline and limited physical functioning at follow-up had ORs of 5.0 (95% CI 1.5 to 16.1) and 2.2 (95% CI 1.1 to 4.6), respectively. In women still working in 2008, the association between neck-shoulder pain in 1994 and in 2008 seemed to be stronger for those in jobs with high job shoulder exposure.

CONCLUSIONS

The results suggest a long-term adverse prognosis for neck-shoulder pain. High job shoulder exposure can worsen this prognosis for those who continue working. This knowledge could influence the counselling given to similar workers and emphasises the need to prevent neck-shoulder pain.

Work-related risk factors for specific shoulder disorders: a systematic review and meta-analysis

The objective of this systematic review and meta-analysis is to examine which work-related risk factors are associated with specific soft tissue shoulder disorders. We searched the electronic databases of Medline and Embase for articles published between 2009 and 24 March 2016 and included the references of a systematic review performed for the period before 2009. Primary cross-sectional and longitudinal studies were included when outcome data were described in terms of clinically assessed soft tissue shoulder disorders and at least two levels of work-related exposure were mentioned (exposed vs less or non-exposed). Two authors independently selected studies, extracted data and assessed study quality. For longitudinal studies, we performed meta-analyses and used GRADE (Grades of Recommendations, Assessment, Development and Evaluation) to assess the evidence for the associations between risk factors and the onset of shoulder disorders. Twenty-seven studies met the inclusion criteria. In total, 16 300 patients with specific soft tissue shoulder disorders from a population of 2 413 722 workers from Denmark, Finland, France, Germany and Poland were included in the meta-analysis of one case-control and six prospective cohort studies. This meta-analysis revealed moderate evidence for associations between shoulder disorders and arm-hand elevation (OR=1.9, 95% CI 1.47 to 2.47) and shoulder load (OR=2.0, 95% CI 1.90 to 2.10) and low to very low evidence for hand force exertion (OR=1.5, 95% CI 1.25 to 1.87), hand-arm vibration (OR=1.3, 95% CI 1.01 to 1.77), psychosocial job demands (OR=1.1, 95% CI 1.01 to 1.25) and working together with temporary workers (OR=2.2, 95% CI 1.2 to 4.2). Low-quality evidence for no associations was found for arm repetition, social support, decision latitude, job control and job security. Moderate evidence was found that arm-hand elevation and shoulder load double the risk of specific shoulder disorders. Low to very-low-quality evidence was found for an association between hand force exertion, hand-arm vibration, psychosocial job demands and working together with temporary workers and the incidence of specific shoulder disorders.

Occupational Safety and Health Conditions Aboard Small- and Medium-Size Fishing Vessels: Differences among Age Groups

Although marine fishing is one of the most hazardous occupations, research on the occupational safety and health (OSH) conditions aboard marine fishing vessels is scarce. For instance, little is known about the working conditions of vulnerable groups such as young and aging fishermen. The objective of the current paper is to study the OSH conditions of young and aging fishermen compared to middle-aged fishermen in the small- and medium-size (SM) marine fishing sector. A cross-sectional study was designed, and 686 fishermen working aboard SM fishing vessels were interviewed to collect information about their safety and health. The associations of physical and psychosocial work conditions with safety and health outcomes, e.g., injuries, illnesses and job satisfaction, are presented. The results of the current study can be utilized in the design of effective accident prevention and OSH training programs for the three age groups and in the regulation of working conditions aboard fishing vessels.

Musculoskeletal symptoms among handicraft workers engaged in hand sewing tasks

Objectives:

This study was conducted to determine the prevalence of musculoskeletal symptoms and associated risk factors among Iranian handicraft workers engaged in different hand sewing tasks.

Methods:

Data were collected using questionnaires (including the Nordic Musculoskeletal Questionnaire) as well as direct observations of posture (using the Rapid Upper Limb Assessment [RULA] method) from 632 workers including carpet handicraft workers (n=222), textiles handicraft workers (n=209), and leather handicraft workers (n=201) in Tabriz, Iran.

Results:

The response rate was 88.8%. The overall prevalence of musculoskeletal complaints, particularly in the neck (57.9%), lower back (51.6%), and shoulders (40.5%) was relatively high. The prevalence of neck and shoulder pain was higher among females and with increasing age. Working posture and fast working were associated with neck, shoulder, and lower back pain. Years worked as a sewing worker was associated with neck and lower back pain. Long duration of continuous sitting work (>2 h) without a break was associated with neck pain. Body mass index, marital status, sport/physical activity, smoking, daily working hours, job satisfaction, and perceived pressure due to work had no effect.

Conclusions:

The findings indicate a high prevalence of musculoskeletal pain among the studied handicraft workers and emphasize the importance of individual, physical, and psychosocial aspects of hand sewing tasks in this regard.

Critical review on the socio-economic impact of tendinopathy

There are currently no studies that determine the total burden that tendinopathy places on patients and society. A systematic search was conducted to understand the impact of tendinopathy. It demonstrated that the current prevalence is underestimated, particularly in active populations, such as athletes and workers. Search results demonstrate that due to the high prevalence, impact on patients' daily lives and the economic impact due to work-loss, treatments are significantly higher than currently observed. A well-accepted definition by medical professionals and the public will improve documentation and increase awareness, in order to better tackle the disease burden.

Subacromial shoulder disorders among baggage handlers: an observational cohort study

PURPOSE

To assess the influence of cumulative employment as baggage handler on the risk of incident subacromial shoulder disorders. Baggage handling is characterized by repetitive work primarily consisting of heavy lifting in awkward positions and time pressure.

METHODS

This cohort study is based on the Copenhagen Airport Cohort consisting of unskilled men with employment at Copenhagen Airport and unskilled men with employment in other firms in the Greater Copenhagen area during the period 1990-2012. Only men were included. We followed the cohort in the National Patient Register and Civil Registration System. The primary exposure was cumulative years of employment as a baggage handler, and the primary outcome was diagnoses and surgical treatment of subacromial shoulder disorders.

RESULTS

The cohort contained 3396 baggage handlers and 63,909 workers in the reference group. Baggage handlers with longer cumulative years of employment had higher incidence compared to baggage handlers with shorter employment; for example, baggage handlers with 10-19 years of employment had incidence rate ratio of 2.07 (95 % confidence interval, 1.27-3.38) compared to baggage handlers with less than 3 years of employment. Spline regression showed an increase in incidence within the first few years after employment whereupon the increased risk remained constant for longer employment. Baggage handlers had increased incidence in younger ages than the reference population.

CONCLUSIONS

In this large cohort study, we found increased incidence of subacromial shoulder disorders for workers with longer cumulative years of employment. These results support that long-term lifting in awkward positions and time pressure influences the risk of subacromial shoulder disorders.

A comparison between different modes of real-time sonoelastography in visualizing myofascial trigger points in low back muscles

OBJECTIVE

Currently, there is a lack of objective means to quantify myofascial trigger points (MTrPs) and their core features. Our research compares (1) MTrPs and surrounding myofascial tissue using two-dimensional grayscale ultrasound (2DGSUS) and vibration sonoelastography (VSE); (2) the accuracy of both modes in visualizing MTrPs; (3) 'active' and 'latent' MTrPs, using VSE; and (4) the accuracy of both modes in visualizing deep and superficially located MTrPs.

METHODS

Fifty participants with more than two MTrPs in their quadratus lumborum, longissimus thoracis, piriformis, and gluteus medius muscles were assigned to an active MTrP (low back pain) group or a latent (currently pain free) MTrP group. MTrP identification was based on their essential criteria. An electronic algometer measured repeatedly the tenderness of MTrPs with reference to pressure pain threshold values. A handheld vibrator was applied over MTrPs, while VSE and 2DGSUS readings were taken using an EUB-7500 ultrasound scanner.

RESULTS

There was a significant difference between MTrP strain and that of the immediately surrounding myofascial tissue, as measured using VSE (P = 0·001). VSE visualized all superficial and deep MTrPs with an accuracy of 100% (for both groups); the blinded results obtained using 2DGSUS achieved 33% and 35% accuracy, respectively. There was no significant difference found between the tissue strain ratios of active and latent MTrPs (P = 0·929).

DISCUSSION

Sonoelastography can visualize superficial and deep MTrPs, and differentiate them from surrounding myofascial structure through tissue stiffness and echogenicity. VSE was more accurate than 2DGSUS in visualizing and imaging MTrPs.

Prevalence of musculoskeletal symptoms among garment workers in Kandal province, Cambodia

OBJECTIVES

The main objectives of this cross-sectional descriptive study were to identify the prevalence of musculoskeletal symptoms and workstation biomechanical risk levels for garment workers in Kandal Province, Cambodia.

METHODS

This cross-sectional descriptive study used multistage sampling techniques to select 714 workers from three garment factories among 22 medium-size factories (250-1,000 workers). Face-to-face interviews and direct observation using the rapid upper limb assessment scale (RULA) were used to collect data.

RESULTS

The response rate was 98.3% (702/714), and the majority (89.3%) of the respondents were female. Ninety-two percent (95% CI=90.0-94.0) of the workers reported musculoskeletal symptoms in at least one body region in the previous 12 months and 89.0% (95% CI=86.7-91.3) of the workers reported such symptoms in the past seven-day period. The neck, shoulder, and lower back were the most affected body regions. In addition, the RULA data showed that 81.2% of the workers' postures were rated as action level 3, indicating that investigation and change were required soon, and that 7.5% their postures were rated as action level 4, indicating that investigation and change were required immediately.

CONCLUSIONS

Cambodian garment workers reported a high prevalence of musculoskeletal symptoms in upper body regions, and their workplaces were rated as high risk ergonomically.

Management of Postoperative Abdominal Wall Pain

Postoperative incisional pain is expected after surgery. However, when a patient is complaining of pain months after surgery, this can be a source of frustration and confusion to the patient and the surgeon. Whether the pain is a result of myofascial pain, incisional hernia, or nerve injury, understanding potential sources of abdominal wall pain can simplify this diagnostic dilemma. This chapter will focus on the diagnosis, treatment, and prevention of postsurgical abdominal wall pain.

Pain intensity, neck pain and longer duration of complaints predict poorer outcome in patients with shoulder pain--a systematic review

Background

Shoulder complaints are common and have an unfavourable prognosis in many patients. Prognostic information is helpful for both patients and clinicians in managing the complaints. The research question was which factors have prognostic value on (un)favourable outcome in patients with shoulder complaints in primary care, secondary care and occupational settings.

Methods

Update of a systematic review in primary care, secondary care and occupational settings.

Results

Nine articles were published since the original review in 2004. Six were of high quality covering a wide variety of prognostic factors and outcome measures. Four studies were conducted in primary care settings. A best evidence synthesis, including the results of the previous systematic review on this topic shows that there is strong evidence that higher shoulder pain intensity, concomitant neck pain and a longer duration of symptoms predict poorer outcome in primary care settings. In secondary care populations, strong evidence was found for the association between greater disability and poorer outcome and between the existence of previous shoulder pain and poorer outcome.

Conclusion

Clinicians may take these factors into account in the management of their patients. Those with a worse prognosis may be monitored more frequently and the treatment plan modified if complaints persist.

Electronic supplementary material

The online version of this article (doi:10.1186/s12891-015-0738-4) contains supplementary material, which is available to authorized users.

Myofascial Trigger Points Then and Now: A Historical and Scientific Perspective

The intent of this article is to discuss the evolving role of the myofascial trigger point (MTrP) in myofascial pain syndrome (MPS) from both a historical and scientific perspective. MTrPs are hard, discrete, palpable nodules in a taut band of skeletal muscle that may be spontaneously painful (i.e., active) or painful only on compression (i.e., latent). MPS is a term used to describe a pain condition that can be acute or, more commonly, chronic and involves the muscle and its surrounding connective tissue (e.g. fascia). According to Travell and Simons, MTrPs are central to the syndrome-but are they necessary? Although the clinical study of muscle pain and MTrPs has proliferated over the past two centuries, the scientific literature often seems disjointed and confusing. Unfortunately, much of the terminology, theories, concepts, and diagnostic criteria are inconsistent, incomplete, or controversial. To address these deficiencies, investigators have recently applied clinical, imaging (of skeletal muscle and brain), and biochemical analyses to systematically and objectively study the MTrP and its role in MPS. Data suggest that the soft tissue milieu around the MTrP, neurogenic inflammation, sensitization, and limbic system dysfunction may all play a role in the initiation, amplification, and perpetuation of MPS. The authors chronicle the advances that have led to the current understanding of MTrP pathophysiology and its relationship to MPS, and review the contributions of clinicians and researchers who have influenced and expanded our contemporary level of clinical knowledge and practice.

Psychosocial Factors and Musculoskeletal Pain Among Rural Hand-woven Carpet Weavers in Iran

Background

Musculoskeletal pain (MSP) is a common and disabling problem among carpet weavers and is linked to physical and psychosocial factors of work. This study aimed to determine the prevalence of MSP, its psychosocial risk factors, and association of pain in each pair of anatomical sites among carpet weavers.

Methods

A cross-sectional study was performed among 546 hand-woven carpet weavers in rural small-scale workshops of Iran. Data were collected by using parts of a standardized CUPID (Cultural and Psychosocial Influences on Disability) questionnaire focused on MSP in 10 body sites, including the low-back, neck, both right and left shoulders, elbows, wrists/hands, individual, physical and psychosocial risk factors. Statistical analysis was performed applying logistic regression models.

Results

Prevalence of MSP in at least one body site was 51.7% over the past month. The most common sites were low back and right shoulder pain 27.4% and 20.1%, respectively. A significant difference was found between the mean number of painful anatomical sites and the level of education, age, physical loading at work, time pressure, lack of support, and job dissatisfaction. In pairwise comparisons, strongest association was found between pain in each bilateral anatomical site (odds ratio = 11.6–35.3; p < 0.001).

Conclusion

In home-based workshops of carpet weaving, psychosocial factors and physical loading were associated with MSP. This finding is consistent with studies conducted among other jobs. Considering the preventive programs, the same amount of attention should be paid to psychosocial risk factors and physical loading. Also, further longitudinal studies are needed to investigate the relationship of psychological factors.

MUSCLES IMPULSES USING TOP-LOADER TYPE OF WASHING MACHINE WITH DIFFERENT ENTRANCE HEIGHTS AND DRUM DEPTHS

This study was conducted to evaluate impulses in muscles during washing using top-loader type of washing machine and to predict the risk of musculoskeletal disorders. Experimental and virtual three-dimensional motion analyses were performed repeatedly with six healthy females using a top-loader type of washing machine at different entrance heights and drum depths. We calculated impulses of muscles from the motion data. Impulses of the latissimus dorsi and erector spinae muscles were the highest of those in the muscles.

The mediating role of work-related musculoskeletal disorders on the link between psychosocial factors and absenteeism among administrative workers

This study aimed to investigate the association between psychosocial factors (i.e., job demand, decision latitude, social support, physical environment, and personal risk factors), work-related musculoskeletal disorders (WRMDs), and productivity as measured by workers' perceived absenteeism. Data were collected from the selected administrative workers (administrative assistant) and analyzed using cross tabulation. The results indicate that all psychological factors are not significantly associated with WRMDs, except for the association between personal risk factors and hip/thigh disorders. Subsequently, WRMDs do not significantly contribute to explaining absenteeism. The managerial and research implications of this study are deliberately discussed.

Environmental and organizational factors associated with elbow/forearm and hand/wrist disorder among sewing machine operators of garment industry in Ethiopia

Occupational health problems related to upper limp musculoskeletal disorders were the major issue among sewing machine operators of garment industries in Ethiopia. The aim of this study was to assess the prevalence and associated risk factors of work related elbow and wrist musculoskeletal disorders among sewing machine operators of garment industries in Galan City, Oromia Regional State. A cross-sectional study was conducted from April 1 to 30, 2012. A total of 422 study subjects were included in this study. Standard Nordic Musculoskeletal Questionnaire was used to collect detailed information on musculoskeletal symptom, sociodemographic data, and factors associated with the problems through face to face interview. From a total of 422 sewing machine operators included in the study 370 (87.7%) were females and 306 (72.5%) were in the age group of <30 years. The prevalence of self-reported work related elbow and wrist musculoskeletal disorders was 40% and 37.7%, respectively. In multivariate analysis, those who had >16 years of service were about five times more likely to develop elbow and wrist musculoskeletal disorders than those who had short (1–5 years) year of services [AOR = 4.7, 95% CI: 1.55–13.02], physical activities [AOR = 5.02, 95% CI: 1.57–16.00], and methods of payment [AOR = 2.01, 95% CI: 1.23–3.28], factors significantly associated with this disorders. Work related elbow and wrist musculoskeletal disorders were high among sewing machine operators in selected garment industries. Moreover, personal and environmental factors were identified as the potential risk factors related to elbow and wrist musculoskeletal disorders among the study group. Therefore, government and the owner of the garment industries should give special attention to prevent and control the problems through proper occupational health and safety policy implementation in the country.

Comorbidities in rotator cuff disease: a case-control study

BACKGROUND

Rotator cuff disease is a common condition in the general population, but relatively little is known about its associated risk factors.

MATERIALS AND METHODS

We have undertaken a large case-control study using The Health Improvement Network database to assess and to quantify the relative contributions of some constitutional and environmental risk factors for rotator cuff disease in the community. Our data set included 5000 patients with rotator cuff disease who were individually matched with a single control by age, sex, and general practice (primary care practice).

RESULTS

The median age at diagnosis was 55 years (interquartile range, 44-65 years). Multivariate analysis showed that the risk factors associated with rotator cuff disease were Achilles tendinitis (odds ratio [OR] = 1.78), trigger finger (OR = 1.99), lateral epicondylitis (OR = 1.71), and carpal tunnel syndrome (OR = 1.55). Oral corticosteroid therapy (OR = 2.03), oral antidiabetic use (OR = 1.66), insulin use (OR = 1.77), and "overweight" body mass index of 25.1 to 30 (OR = 1.15) were also significantly associated. Current or previous smoking history, body mass index of greater than 30, any alcohol intake, medial epicondylitis, de Quervain syndrome, cubital tunnel syndrome, and rheumatoid arthritis were not found to be associated with rotator cuff disease.

CONCLUSIONS

We have identified a number of comorbidities and risk factors for rotator cuff disease. These include lateral epicondylitis, carpal tunnel syndrome, trigger finger, Achilles tendinitis, oral corticosteroid use, and diabetes mellitus. The findings should alert the clinician to comorbid pathologic processes and guide future research into the etiology of this condition.

Women performing repetitive work: is there a difference in the prevalence of shoulder pain and pathology in supermarket cashiers compared to the general female population?

OBJECTIVES

Shoulder disorders in the occupational environment have been widely studied, but the quality of research and methodology applied vary. Little has been done to ascertain whether shoulder pain in female repetitive workers is due to any verifiable pathology, or to compare findings with the general population. Therefore, we decided to evaluate the prevalence of self-reported shoulder pain in a group of female supermarket cashiers and in the general female population using a standardized questionnaire. Shoulder pain prevalence was then compared to imaging findings in order to assess specific and non-specific pain prevalence.

MATERIAL AND METHODS

196 cashiers and 302 controls filled in a standardized shoulder questionnaire and underwent an imaging examination of a shoulder.

RESULTS

The prevalence of shoulder pain was significantly higher in the group of cashiers (46.4%) than in the general population (25.5%) (OR = 1.821; 95% CI: 1.426-2.325). Specific pain prevalence was higher among the controls (19.5%) than among the cashiers (13.2%).

CONCLUSIONS

The more frequent reports of shoulder pain in the supermarket cashiers are not correlated with a higher prevalence of imaging abnormalities. The causes of these more frequent complaints should be probably sought in the psycho-social and occupational environment.

Impacts of differences in epidemiological case definitions on prevalence for upper-extremity musculoskeletal disorders

OBJECTIVE

The aim of this study was to systematically evaluate prevalence based on variations in case definitions used for epidemiological studies of musculoskeletal disorders (MSDs).

BACKGROUND

Prior studies of MSDs have mostly relied on a single case definition based on questionnaires.

METHOD

In a multicenter prospective cohort study, we systematically collected data to evaluate impacts of differences in case definitions of MSDs on prevalence of three common musculoskeletal disorders: (a) shoulder tendinosis, (b) lateral epicondylalgia, and (c) carpal tunnel syndrome. Production workers were from 21 employment settings in three diverse U.S. states and performed widely varying work. All workers completed laptop-administered structured interviews, two standardized physical examinations, and nerve conduction studies (NCS). Case definitions included symptoms only, and symptoms plus physical examinations and/or NCS.

RESULTS

A total of 1,227 subjects had complete health data at baseline. The prevalence for shoulder tendinosis is 23.0% if only glenohumeral pain is used for a case definition, compared with 8.0% if a combination of pain plus a positive supraspinatus test is used. The prevalence for lateral epicondylalgia varied on the basis of lateral elbow pain (12.0%), pain plus tenderness on palpation (9.9%), or pain plus tenderness on palpation plus resisted wrist or middle finger extension (3.5%). Carpal tunnel syndrome prevalence varied on the basis of tingling or numbness in a median nerve-served digit (29.9%) or tingling or numbness plus NCS abnormalities consistent with carpal tunnel syndrome (9.0%).

CONCLUSION

Variations in epidemiological case definitions have major impacts on prevalence of common MSDs. Wide-ranging differences in prevalence may have impacts on purported risk factors that need to be determined.

The effects of a medical hypnotherapy on clothing industry employees suffering from chronic pain

Background

Problems associated with pain in several body regions due to work-related musculoskeletal disorders (WRMDs), repetitive movement and negative stress at work are quite common in many manufacturing industries of Latvia, int.al. clothing industry. The aim of this study was to evaluate efficiency of the psychotherapeutic intervention using medical hypnotherapy (MH) program for mind-body relaxation with pain-blocking imagery, cognitive restructuring of unpleasant physical and emotional experience.

Methods

300 sewers and 50 cutters with chronic pain were involved in the study. Self-rated WRMDs symptoms, pain intensity and interference were assessed using the extended version of Nordic Musculoskeletal Questionnaire and Brief Pain Inventory Scale. Assessment of the functional state of muscles was carried out using myotonometric (MYO) measurements. Work heaviness degree was estimated via heart rate monitoring (HRM). The MH program was composed of cognitive hypnotherapy and self-hypnosis training. Sunnen Trance Scale was used to determine person’s hypnotic susceptibility. Life quality assessment before and after MH program was carried out using Quality of Life Scale.

Results

At the beginning of MH program sessions both sewers and cutters reported on pain interference with general activities, mood, sleep, normal work, etc., but after MH the interference of pain significantly decreased. HRM data confirmed that work heaviness degree of sewers and cutters can be referred to as light and moderate work (energy expenditure for their tasks varies from 3.4 till 4.7 kcal/min). Using MYO measurements it was stated that before MH 22% of workers involved in the study fell under III MYO category indices, consequently, their muscle tone was increased, which is associated with muscular fatigue. After MH muscle tone remained within the normal range meaning that they were able to adapt to the existing workload (II MYO category) or fully relax (I MYO category).

Conclusions

MH program including exercises-workouts, cognitive hypnotherapy and self-hypnosis training sessions is an effective method to decrease composite chronic pain intensity for sewers and cutters, as well as to decrease psychogenic tension and muscle fatigue (proved by objective measurements of muscles tone) and to increase the life quality.

Avaliação do risco ergonômico em trabalhadores da indústria têxtil por dois instrumentos: quick exposure check e job factors questionnaire

A análise dos fatores de risco ergonômicos presentes em indústrias têxteis auxilia no planejamento de estratégias que contribuem para a melhora das condições de trabalho e redução dos distúrbios osteomusculares. Este estudo se propôs a mensurar os níveis de exposição aos fatores de risco ergonômicos em trabalhadores de dois setores de produção de uma indústria têxtil. Para tanto, os instrumentos Job Factors Questionnaire (JFQ) e o Quick Exposure Check (QEC) foram aplicados em 107 trabalhadores. Os resultados foram analisados por estatística descritiva. O teste de Mann-Whitney foi utilizado para comparação dos resultados obtidos entre os setores de produção. O diagnóstico do nível de exposição ao risco ergonômico, obtido por ambos os instrumentos, foi moderado. Os fatores de risco considerados pelo JFQ como mais criticos estão relacionados à temperatura ambiental; postura mantida em longos períodos de tempo; posturas inadequadas para coluna e continuar trabalhando quando está com alguma dor ou com alguma lesão. O QEC identificou as regiões de coluna lombar e punhos/mãos como expostas ao alto risco. Não houveram diferenças estatisticamente significante entre os setores.

A systematic comparison between subjects with no pain and pain associated with active myofascial trigger points

OBJECTIVE

To determine whether standard evaluations of pain distinguish subjects with no pain from those with myofascial pain syndromes (MPS) and active myofascial trigger points (MTrPs) and to assess whether self-reports of mood, function, and health-related quality of life differ between these groups.

DESIGN

A prospective, descriptive study.

SETTING

University.

PATIENTS

Adults with and without neck pain.

METHODS

We evaluated adults with MPS and active (painful) MTrPs and those without pain. Subjects in the "active" (A) group had at least one active MTrP with spontaneous pain that was persistent, lasted longer than 3 months, and had characteristic pain on palpation. Subjects in the "no pain" (NP) group had no spontaneous pain. However, some of these subjects had discomfort upon MTrP palpation (latent MTrP), whereas others in the NP group had no discomfort upon palpation of nodules or had no nodules.

OUTCOME MEASURES

Each participant underwent range of motion measurement, a 10-point manual muscle test, and manual and algometric palpation. The latter determined the pain/pressure threshold using an algometer of 4 predetermined anatomic sites along the upper trapezius. Participants rated pain using a verbal analog scale (0-10) and completed the Brief Pain Inventory and Oswestry Disability Scale (which included a sleep subscale), the Short -Form 36 Health Survey, and the Profile of Mood States.

RESULTS

The A group included 24 subjects (mean age 36 years; 16 women), and the NP group included 26 subjects (mean age 26 years; 12 women). Group A subjects differed from NP subjects in the number of latent MTrPs (P = .0062), asymmetrical cervical range of motion (P = .01 for side bending and P = .002 for rotation), and in all pain reports (P < .0001), algometry (P < .03), Profile of Mood States (P < .038), Short Form 36 Health Survey (P < .01), and Oswestry Disability Scale (P < .0001).

CONCLUSION

A systematic musculoskeletal evaluation of people with MPS reliably distinguishes them from subjects with no pain. The 2 groups are significantly different in their physical findings and self-reports of pain, sleep disturbance, disability, health status, and mood. These findings support the view that a "local" pain syndrome has significant associations with mood, health-related quality of life, and function.

Musculoskeletal symptoms among female garment factory workers in Sri Lanka

OBJECTIVES

To assess the prevalence of musculoskeletal symptoms and their association with sociodemographic risk factors among female garment factory workers in Sri Lanka.

METHODS

1058 randomly selected female garment factory workers employed in the free trade zone of Kogalla, Sri Lanka were recruited to complete two interviewer-administered questionnaires assessing musculoskeletal symptoms and health behaviors.

DISCUSSION

Musculoskeletal complaints among female garment workers in the FTZ of Kogalla are less common than expected. Sociocultural factors may have resulted in underreporting and similarly contribute to the low rates of healthcare utilization by these women.

RESULTS

164 (15.5%) of workers reported musculoskeletal symptoms occurring more than 3 times or lasting a week or more during the previous 12-month period. Back (57.3%) and knee (31.7%) were the most common sites of pain. Although most symptomatic women reported that their problems interfered with work and leisure activities, very few missed work as a result of their pain. Prevalence correlated positively with increased age and industry tenure of less than 12 months. Job type, body mass index, and education were not significant predictors of musculoskeletal symptoms.

Occurrence and co-existence of localized musculoskeletal symptoms and findings in work-attending orchestra musicians - an exploratory cross-sectional study

Background

Due to ergonomic exposure musicians are at risk of work-related musculoskeletal disorders in the neck, back, and upper extremities. The literature confirms musculoskeletal problems in these anatomic regions among orchestra musicians.

Methods

An explorative cross-sectional study among 441 musicians from six Danish symphony orchestras; 216 underwent a clinical examination constructed for the purpose. Prior to the examination the musicians rated their maximally perceived trouble within the last week on a scheme blinded to the examiner. Accessibility to the clinical examination differed between orchestras.

The aims were to assess the prevalence of 1) perceived symptoms within the previous week in the neck, back and limbs and of 2) clinical findings in the neck, back, and upper extremities, and 3) to investigate the co-existence of the perceived symptoms and clinical findings.

Results

Symptoms and findings were most common in the neck, back, and shoulders. Due to a poor co-existence between self-reported symptoms and clinical findings musicians experiencing bodily trouble could not be identified through this clinical examination. Free accessibility to the examination was of major importance to participation.

Conclusions

In compliance with the purpose, perceived symptoms within the previous week and present clinical findings were assessed. Although both symptoms and findings were most frequent in the neck, back, and shoulders the co-existence of anatomically localized symptoms and findings was generally quite poor in this study.

Discrepancy between symptoms and findings might be caused by the participants currently attending work and therefore being relatively healthy, and the fluctuating nature of musculoskeletal problems. Furthermore from a comparison of different measuring units - self-reported symptoms being period prevalence rates and clinical findings point prevalence rates; a bias which may also be inherent in similar studies combining self-reported questionnaire data and clinical findings.

Understanding the link between psychosocial work stressors and work-related musculoskeletal complaints

It is well established that psychosocial work stressors relate to employees' work-related musculoskeletal disorder (WRMSD) symptoms. Using a model investigating psychological strain as a mediator between work stressors and WRMSD complaints, this study demonstrated that high levels role conflict, low job control, and low safety-specific leadership are associated with increased employee strain. Strain, in turn, was related to higher levels of WRMSD symptoms of the wrist/hand, shoulders, and lower back. Partial mediation of some relationships was also found, suggesting that additional meditational mechanisms for the relationships between stressors and musculoskeletal symptoms are plausible. This work supports the notion that psychosocial stressors in the work environment have important links to employee health, especially WRMSDs.

The course of physical functional limitations and occupational conditions in a middle-aged working population in France

Background

Physical functional limitations (PFL) have mainly been studied in older populations. The aim of this study was to better understand the course of PFL and associations with occupational factors by gender in a middle-aged working population.

Methods

The data came from 16,950 workers in the ESTEV (Enquête Santé Travail et Vieillissement) cohort in France. PFL were assessed using the physical abilities section of the Nottingham Health Profile. Occupational conditions were measured with a self-administered questionnaire covering physical and psychosocial factors in 1990 and 1995. Multivariate analyses were used to assess the associations.

Results

The PFL appearance rate in 1995 was the same by gender (6.3%); the rate of PFL recovery was higher in men (23.9% versus 20.9%). Age was an independent factor of PFL at age 47 years or older in both genders after adjusting for confounding factors. The PFL appearance rate in 1995 was higher with physical occupational exposure in 1990, such as awkward work with a dose relation in both genders, while the PFL recovery rate decreased significantly only for men. Exposure to psychosocial occupational conditions, such as having the means to produce quality work in 1990, was significantly associated with a decreased PFL appearance rate in 1995 in both genders, and having high decision latitude in 1990 was associated with a decreased PFL appearance rate in 1995 only in men. Changes in exposure to occupational factors between 1990 and 1995 were associated with the PFL appearance and recovery rates in 1995 in both genders.

Conclusions

After five years, the course of PFL in this working population changed and was associated with physical and psychosocial occupational factors. Relationships were stronger for the PFL appearance rate in both genders and were weaker for recovery from PFL, mainly among women.

Allogenous tendon stem/progenitor cells in silk scaffold for functional shoulder repair

Tendon stem/progenitor cells (TSPCs) were recently identified within tendon tissues. The aim of this study was to investigate TSPC-seeded knitted silk-collagen sponge scaffold for functional shoulder repair. The multidifferentiation potential, proliferation, and immune properties of TSPCs were investigated in vitro, while the efficacy of TSPC-seeded knitted silk-collagen sponge scaffolds in promoting rotator cuff regeneration was evaluated in vivo within a rabbit model. TSPCs, which exhibited universal stem cell characteristics (i.e., clonogenicity, high proliferative capacity, and multidifferentiation potential), nonimmunogenicity, and immunosuppression, proliferated well on our scaffold in vitro. Implantation of allogenous TSPC-seeded scaffolds within a rabbit rotator cuff injury model did not elicit an immunological reaction, but instead increased fibroblastic cell ingrowth and reduced infiltration of lymphocytes within the implantation sites at 4 and 8 weeks postsurgery. After 12 weeks, the allogenous TSPC-treated group exhibited increased collagen deposition and had better structural and biomechanical properties compared to the control group. This study thus demonstrated that the allogenous TSPC-seeded knitted silk-collagen sponge scaffold enhanced the efficacy of rotator cuff tendon regeneration by differentiating into tenocytes, and by secreting anti-inflammatory cytokines that prevent immunological rejection. Hence, allogenous TSPC-seeded knitted silk-collagen sponge scaffolds can be a clinically useful application for tendon tissue engineering.

Scapular dyskinesis in trapezius myalgia and intraexaminer reproducibility of clinical tests

The aims were to test the intraexaminer reproducibility and report the presence of specific clinical variables of scapular dyskinesis in cases with trapezius myalgia and healthy controls, along with general health and work ability. A total of 38 cases and 23 controls were tested for scapular dyskinesis, general health, and work ability, and 19 cases and 14 controls participated in the reproducibility study. Intraexaminer reproducibility was good to excellent for 6 of 10 clinical variables (Intraclass Correlation Coefficient [ICC] 0.76-0.91; kappa 0.84-1.00), and fair to good for four variables (ICC 0.42-0.74), test for muscular weakness having the lowest ICC (0.42). Cases showed significantly larger medial border misalignment, larger lower horizontal distance of the inferior scapular angle and larger passive shoulder internal rotation, by 110% (1.02 cm), 15% (1.38 cm), and 8% (5.5°), respectively. Cases with the highest degree of scapular dyskinesis showed reduced work ability and general health. The present specific clinical variables on scapular dyskinesis showed satisfactory intraexaminer reproducibility. An increased standardization must be implemented to increase reproducibility of tests for muscular weakness, and the interexaminer reproducibility must be tested for all variables. Finally, scapular dyskinesis in cases with trapezius myalgia must be followed longitudinally for clinical importance.

Characteristics of work-related musculoskeletal disorders in Korea and their work-relatedness evaluation

Work-related musculoskeletal disorders (WMSDs) can be compensated through the Industrial Accident Compensation Insurance Act. We looked at the characteristics of WMSDs in worker's compensation records and the epidemiological investigation reports from the Occupational Safety and Health Research Institute (OSHRI). Based on the records of compensation, the number of cases for WMSDs decreased from 4,532 in 2003 to 1,954 in 2007. However the proportion of WMSDs among the total approved occupational diseases increased from 49.6% in 2003 to 76.5% in 2007, and the total cost of WMSDs increased from 105.3 billion won in 2004 to 163.3 billion won in 2007. The approval rate of WMSDs by the OSHRI accounted for 65.6%. Ergonomic and clinical characteristics were associated with the approval rate; however, the degenerative changes had a minimal affect. This result was in discordance between OSHRI and the Korea Workers' Compensation & Welfare Service. We presumed that there were perceptional gaps in work-relatedness interpretation that resulted from the inequality of information in ergonomic analyses. We propose to introduce ergonomic analysis to unapproved WMSDs cases and discuss those results among experts that will be helpful to form a consensus among diverse groups.