Movements of the wrist and the risk of carpal tunnel syndrome: a nationwide cohort study using objective exposure measurements

Carpal tunnel syndrome severity and work: a case-control study

BACKGROUND

Carpal tunnel syndrome (CTS) is a socially relevant condition. Risk factors associated with CTS severity and work have not been explored.

AIMS

This case-control study aims to investigate the association between CTS severity and occupational biomechanical overload considering personal anthropometric risk factors.

METHODS

We consecutively enrolled one CTS case for two controls. CTS cases were grouped into three classes of progressive clinical and electrophysiological severity according to two validated scales. Job titles were coded according to the International Standard Classification of Occupations (ISCO 88) and grouped into two broad socio-occupational categories: blue-collar and white-collar workers.The associations between CTS (or CTS severity) and blue-collar status were assessed using unconditional (or multinomial) logistic regression models adjusted for age, gender, centre and two anthropometric indexes: wrist-palm ratio and waist-stature ratio. Odds ratios (OR) or relative risk ratio and 95% confidence intervals (95% CI) were calculated, as appropriate.

RESULTS

We included 183 cases and 445 controls. Blue-collar status was a risk factor for CTS (OR 2.4; 95% CI 1.5-3.8). Among job titles, vine and/or olive tree growers (OR 6.0; 95% CI 2.0-17.9) and food processing workers (OR 4.8; 95% CI 1.5-15.2) were at higher risk. At multinomial logistic regression analysis, blue-collar status and the two anthropometric indexes were associated with moderate/severe CTS, after mutual adjustment.

CONCLUSIONS

Blue-collar workers showed a higher risk of CTS than white-collar workers, adjusting for anthropometric and body measures as well. Preventive interventions should be addressed to decrease the biomechanical overload of the upper limbs and limit the overweight.

Morphological analysis of the median nerve in the carpal tunnel during wrist movements, finger pinching and palm loading

The aim of this study was to analyze the morphology of the median nerve (MN) in the carpal tunnel during hand motion and palmar load in healthy participants using ultrasound. Twenty healthy participants (10 men and 10 women) were enrolled in the study. Wrist flexion angle is negatively correlated with cross-sectional area (CSA) and perimeter, and positively correlated with circularity, whereas wrist extension angle is negatively correlated with MNCSA and circularity. At 15°, 45°, and 60° wrist flexion and extension, both MNCSA and perimeter were significantly smaller than at neutral (all P < 0.05). MN circularity was significantly greater at 30°, 45°, and 60° wrist flexion than at neutral (all P < 0.05). At 30° ulnar deviation of the wrist, MNCSA and perimeter were significantly smaller than the neutral position, while circularity was significantly larger (all P < 0.05). At 15° of wrist radial deviation, MNCSA and perimeter were significantly smaller than at the neutral position (all P < 0.05). Compared to the 40 % maximum voluntary effort (MVE), thumb-ring finger pinch (10 %MVE) resulted in significantly higher MNCSA and perimeter, while circularity was noticeably smaller (all P < 0.05). In the neutral position, no differences were observed in MNCSA, perimeter and circularity unloaded at 100 g, 200 g, 300 g, 400 g and 500 g palmar loads (all P > 0.05). The results indicate that wrist positions involving flexion, extension, and deviations, as well as finger pinch, can significantly impact the morphology of the MN. This is an important step in understanding the biomechanics of MN compression within the carpal tunnel.

Validity of an expert-based job exposure matrix of hand-wrist physical exposures and their prospective associations with carpal tunnel syndrome

BACKGROUND

Epidemiological studies of occupational risk factors for rare disorders require large study populations with adequate exposure estimates. Job exposure matrices (JEMs) linked to national information on standardized job titles may enable such large studies. We aimed to establish and validate a JEM for occupational hand-wrist exposures that could be linked to Danish national register data on job titles and hand-wrist disorders.

METHODS

We developed a JEM for hand-wrist repetition, force, vibration, and computer work in 96 job groups covering 91% of the 2227 occupational titles in the Danish version of the International Standard Classification of Occupation-88, and examined inter-rater reliability of five expert ratings. Poisson regression models were used to estimate incidence rate ratios for the association of carpal tunnel syndrome (CTS) with the level of repetitive movements, force, vibration, and hours of computer work described by the JEM, adjusted for relevant confounders.

RESULTS

The JEM based on expert ratings had fair to good interrater reliability. The incidence of CTS increased with increasing levels of force, hand-wrist repetition, and vibration, Exposure-response patterns for repetition and vibration became less consistent after adjustment for force. The interaction between repetition and force was complex and did not support an overall positive interaction. Computer work was negatively associated with incident CTS.

CONCLUSION

The JEM was able to identify known risk factors for CTS consistent with current evidence, and provided further associations on exposure-response patterns, mutual exposure adjustment, and interaction effects between repetition and force. The reliability of expert assessments of hand-wrist physical exposures was fair to good.

Carpal tunnel syndrome and occupational hand exposures: a Danish nationwide cohort study

OBJECTIVES

The aim was to examine exposure-response relations between occupational hand exposures and carpal tunnel syndrome (CTS) and to compare the relation between surgery-treated and non-surgery-treated CTS. The secondary aim was to study sex-specific differences in exposure-response relations.

METHODS

We conducted a nationwide register-based cohort study of all persons born in Denmark (1945-1994). During follow-up (2010-2013), we identified first-time events of CTS. Occupational hand exposure estimates the year before each follow-up year were obtained by linking individual occupational codes with a job exposure matrix. We used multivariable logistic regression equivalent to discrete survival analysis based on sex and surgery. The excess fraction of cases was calculated.

RESULTS

For both sexes, exposure-response relations were found for all occupational hand exposures. Among men, we found ORadj of 3.6 (95% CI 3.2 to 3.8) for hand-related force, 2.9 (95% CI 2.5 to 3.2) for repetitive hand movements, 3.8 (95% CI 2.7 to 5.2) for non-neutral hand posture and 2.5 (95% CI 2.2 to 2.7) for hand-arm vibration in the highest exposure groups. For combined exposure (hand load), ORadj was 3.5 (95% CI 3.1 to 4.0). Slightly higher ORsadj were generally found for surgery-treated CTS compared with non-surgery-treated CTS for both sexes. When comparing sex, somewhat higher ORsadj were found among men. The excess fraction was 42%.

CONCLUSIONS

Occupational hand exposures carried a 3-5-fold increased risk of CTS with slightly higher risks for surgery-treated compared with non-surgery-treated CTS. Even though CTS occurs more frequently among women, somewhat higher exposure-response relations were found for men compared with women. In the general working population, a substantial fraction of first-time CTS could be related to occupational hand exposures.

Effects of the COVID-19 Pandemic on Hand and Arm Dysfunction: A Google Trends Analysis

Introduction The COVID-19 pandemic prompted individuals to make a number of lifestyle alterations. Few studies have examined the development of any hand and/or arm dysfunctions that may have resulted. The purpose of this study was to identify hand and/or arm overuse injuries that may have occurred as a result of the stay-at-home orders during the COVID-19 pandemic. Methods A Google Trends analysis of the terms "hand pain," "carpal tunnel syndrome," "cubital tunnel syndrome," "trigger finger," "de Quervain tenosynovitis," "elbow pain," "tennis elbow," "golfer's elbow," "thumb base arthritis," and "extensor carpi ulnaris tenosynovitis" in the United States, United Kingdom, Canada, and India was performed from June 2019 to January 2023. The noted timeframe was divided into quarters of 47 weeks, with the first quarter (June 2, 2019, through April 19, 2020) serving as a pre-pandemic baseline. The analysis compared initial results noted in the first quarter to individual results from the second, third, and fourth quarters. Results The most notable findings were the upward trends of the terms "hand pain," "carpal tunnel," and "trigger finger." Specifically, India showed a significant increase in the terms "hand pain" and "carpal tunnel syndrome" in the second, third, and fourth quarters. The United States additionally showed a significant upward trend in the terms "carpal tunnel syndrome" and "trigger finger" in the second, third, and fourth quarters. The United Kingdom also reported a significant upward trend in the term "trigger finger" in the second, third, and fourth quarters. Conclusion Numerous factors likely contributed to the increased interest in these terms, such as the increase in telework and associated mobile device usage due to lockdown during the COVID-19 pandemic. Movements associated with performing these tasks may have led to an increased prevalence of hand pain, thus prompting increased queries of these terms through an online search engine.

Physical and psychosocial work-related exposures and the incidence of carpal tunnel syndrome: A systematic review of prospective studies

This systematic review summarizes the evidence on associations between physical and psychosocial work-related exposures and the development of carpal tunnel syndrome (CTS). Relevant databases were searched up to January 2020 for cohort studies reporting associations between work-related physical or psychosocial risk factors and the incidence of CTS. Two independent reviewers selected eligible studies, extracted relevant data, and assessed risk of bias (RoB). We identified fourteen articles for inclusion which reported data from nine cohort studies. Eight reported associations between physical exposure and the incidence of CTS and five reported associations between psychosocial exposures and the incidence of CTS. Quality items were generally rated as unclear or low RoB. Work-related physical exposure factors including high levels of repetition, velocity, and a combination of multiple physical exposures were associated with an increased risk of developing CTS. No other consistent associations were observed for physical or psychosocial exposures at work and CTS incidence.

Effectiveness of prevention exercises protocol among office workers with symptoms of carpal tunnel syndrome

OBJECTIVES

Carpal tunnel syndrome (CTS) is common among office workers and limits functional hand ability and the ability to work. Carpal tunnel syndrome prevention programs implementation are still insufficient among office workers. In view of the fact that physical activity is the best method of preventing musculoskeletal complaints the aim of the study was to evaluate the effectiveness of prevention exercises protocol for hand and wrist pain among office workers.

MATERIAL AND METHODS

Study group consists form 62 office workers, reporting complaints of hand and wrist pain. Exercise group it was 49 subjects who performed the exercise protocol and the non-exercise group consisted of 13 subjects. An exercises program, consisting of 7 exercises. The program was planned for daily routine during 8 weeks. The effectiveness of the exercise program was assessed by physical parameters (hand grip and pinch grip strength, force of forearm muscles) and questionnaires (Visual Analog Scale pain scale, Carpal Tunnel Syndrome Symptom Severity Scale, and Carpal Tunnel Syndrome Functional Status Scale functional hand assessment questionnaires) were performed. Assessment was performed before and after the intervention.

RESULTS

Statistical analysis of the data showed significant changes in the value of measured hand grip of the right hand (Z = -2.85, p < 0.01). For pinch grip, changes were significant for both the right (Z = -2.12, p < 0.05) and the left hands (Z = -2.35, p < 0.05). Functional performance improved significantly in bought groups. There was no statistically significant change in the intensity of experienced pain.

CONCLUSIONS

The results of the study indicate that performing a preventive exercise program regularly has an effect on increasing forearm muscle strength in a group of office workers. Office workers with symptoms of CTS who exercised regularly had higher results in hand grip and pincer grip strength. Exercises do not affect the level of pain complaints, which may indicate a more complex etiology of pain perception in this study group. Int J Occup Med Environ Health. 2024;37(1):45-57.

Prevalence of Carpal Tunnel Syndrome Symptoms Among Young Dentists

Objectives Although age is a risk factor, carpal tunnel syndrome (CTS) can also affect younger individuals, particularly those involved in activities or occupations that require repetitive hand movements, forceful gripping, or prolonged wrist flexion/extension. This case-control study aimed to examine the prevalence of CTS symptoms and frequent object dropping among a group of young dentists who are exposed to CTS risk factors. Additionally, other reported risk factors for CTS, such as sex, obesity, and square wrist sign, were also investigated. Methods A total of 74 dentists (48 women, mean age 28.5 years), who are working at Istanbul Faculty of Dentistry, the largest dental school in Istanbul, which is the biggest city in Turkey, were included in the study. Additionally, 61 age- and sex-matched controls (38 women, mean age 27.9 years) were also recruited. The Edinburgh Hand Preference Questionnaire, Boston Carpal Tunnel Syndrome Questionnaire (BCTQ), a questionnaire for object dropping and occupational hand usage, anthropometric measurements of the hands, clinical neurologic examination, and electromyography intended for the detection of CTS were performed. Results The dentists had a higher total weekly hand usage duration compared to the controls (66.3 vs 44.8 hours, p<0.001). BCTQ scores and the frequency of object dropping were also significantly higher in dentists compared to controls (respective p values: 0.011, 0.003). Positive correlations were found between BCTQ scores, hand usage durations, and object dropping (respective p values: 0.001, <0.001). BCTQ scores were higher in women than in men (p=0.027). Electrophysiologic evidence of CTS was found in one dentist. Conclusions Symptoms of CTS may manifest in individuals at a younger age than predicted, primarily influenced by their occupation and the duration of hand usage. Dentists, in particular, report a higher incidence of complaints related to object dropping, which can be attributed to their frequent use of specialized tools and engagement in delicate tasks, resulting in heightened awareness. However, it can also potentially serve as an indicator of CTS.

Carpal tunnel syndrome: updated evidence and new questions

Carpal tunnel syndrome is the most common entrapment neuropathy, affecting quality of life for many people. Although it is a well recognised condition, new insights into epidemiology, diagnosis, and treatment have emerged in the past 6 years. The availability of disease-modifying treatments for rare systemic disorders associated with carpal tunnel syndrome (eg, amyloidosis) should alert clinicians to these diagnostic possibilities. Besides clinical evaluation and electrophysiology, the role of ultrasonography as a diagnostic tool has been confirmed and new ultrasound techniques have been applied, the clinical use and feasibility of which require further investigation. Surgical and non-surgical interventions are beneficial for the treatment of carpal tunnel syndrome and several treatment options are now available, giving clinicians the possibility to choose the best approach for every patient. New diagnostic and therapeutic techniques require further validation.

Prevalence status and associated factors of wrist postural injury in the Chinese occupational population

Objective

This study investigated the prevalence of wrist injuries in 15 industries and different types of work in China. Study on the associated factors of wrist injuries provides a scientific basis for prevention and treatment of wrist diseases in occupational workers.

Methods

A cross-sectional study of musculoskeletal symptoms of related practitioners in 15 industries, including automobile manufacturing, was conducted to retrieve worker demographic information, working wrist posture, and pain conditions. Multivariable binary logistic regression analyses were performed to identify factors associated with work-related musculoskeletal disorders (WMSDs).

Results

The prevalence of wrist injuries among the study population was 13.2%. Toy manufacturing, animal husbandry, automobile manufacturing, shoe manufacturing, and biopharmaceutical manufacturing had the highest wrist injury rates at 29.1, 19.1, 14.9, 14.9, and 14.0%, respectively. Among the types of jobs, enamel workers (63.0%), butchers (43.6%), combers (32.5%), welders (31.3%), and scaffolders (26.5%) had the highest prevalence rates. Based on the final multivariate logistic regression analysis: female [odds ratios (OR) = 1.24; 95% confidence interval (CI), 1.15-1.35], 6-10 years of service (OR = 1.11; 95% CI, 1.03-1.18), >10 years of service (OR = 1.15; 95% CI, 1.06-1.25), frequent upward and downward flexion in wrist posture at work (OR = 1.81; 95% CI, 1.84-2.11), and frequent wrist placement on the edge of angular objects increased the OR of injury (OR = 1.52; 95% CI, 1.44-1.61). Need to squeeze objects tightly while working (OR = 1.72; 95% CI, 1.57-1.89), prolonged wrist flexion (OR = 1.86; 95% CI, 1.75-1.97), and work hand position above the shoulder for prolonged periods (OR = 1.11; 95% CI, 1.04-1.19) also suggested the relationship between these factors and the higher prevalence of wrist injury in the workers. The associated factor was physical activity (OR = 0.86; 95% CI, 0.80-0.94).

Conclusion

This study suggested the relationship between these factors and the higher prevalence of wrist injury in the toy manufacturing, animal husbandry, automobile manufacturing, and shoe-making industries, enamel workers, butchers, and combers. And are work types that require special attention. Females, working age, physical activity, and abnormal posture of the wrist were factors significantly associated with WMSDs.

Work-relatedness of carpal tunnel syndrome: Systematic review including meta-analysis and GRADE

Background and Aims

Carpal tunnel syndrome (CTS) is the most common peripheral nerve entrapment syndrome with a high prevalence among workers. Insights on the physical work-related risk factors is necessary to develop appropriate preventative methods. The objective of this systematic review, including meta-analyses, is to assess which physical work-related risk factors are associated with carpal tunnel syndrome.

Methods

Systematic literature searches were carried out using PubMed and Embase until September 6, 2021. Studies were included if: (1) CTS was clinically assessed, (2) the studies were prospective cohort studies, and (3) the exposure was reported using terms of exposed/less or nonexposed. Risk of bias was assessed using the Quality in Prognosis Studies (QUIPS) tool. Quality of evidence was assessed using the Grading of Recommendations, Assessment, Development, and Evaluation (GRADE).

Results

In total, 9270 patients with CTS from a population of 1,051,707 workers were included from 17 studies. Meta-analyses revealed high-quality evidence for associations between CTS and high exposures to repetition (hazard ratio [HR] 1.87, 95% CI 1.42-2.46), force intensity (HR 1.84, 95%CI 1.22-2.79), exposures above hand activity level of ACGIH (HR 1.75, 95%CI 1.40-2.17), and the Strain Index >10 (HR 1.58, 95% CI 1.09-2.30). No significant associations were found for pinch gripping, hand-arm vibration or force duration. High computer-use exposure was significantly associated with a decreased rate of work-related CTS (HR 0.28, 95% CI 0.12-0.64).

Conclusion

This systematic review of prospective cohort studies found high certainty for an increased rate of CTS due to a high Strain Index, exposures exceeding the Activity Level of ACGIH, and high force intensity and high repetition. Workers performing tasks requiring both high force and high repetition even have a higher rate of developing CTS.

Women's wrist and elbow at work: analysis of acute injuries and cumulative trauma disorders to improve ergonomics in female-dominated activities

The aim of this study is to analyse women's wrist and elbow acute work injuries together with cumulative trauma disorders, such as carpal tunnel syndrome (CTS) and epicondylitis. Five years records (2015-2019) on women's wrist/elbow acute work injuries and CTS/epicondilytis, from Italian National Compensation Authority, were collected and pooled all together as 'dis-ac' (disorders + acute) events. A statistical analysis was performed in comparing the different female-dominated work sectors. Results showed that hairdressing/laundry sector was associated with the highest risk for wrist acute work injuries and cleaning for elbow while manufacturing for CTS and epicondylitis. Hairdressing/laundry and manufacturing were associated with the highest risk for dis-ac events (hairdressing: wrist dis-ac OR: 4.89; CI 95% 4.22-5.67; elbow dis-ac OR: 3.70; CI 95% 2.99-4.58; manufacturing: wrist dis-ac OR: 3.39; CI 95% 3.13-3.66; elbow dis-ac OR: 2.45; CI 95% 2.20-2.73). The relationship between acute injuries and cumulative trauma disorders is discussed to preserve women's safety and health in ergonomics.Practitioner Summary: Women's wrist and elbow acute work injuries and cumulative trauma disorders (carpal tunnel syndrome and epicondylitis) were analysed and studied all together (dis-ac events) in female-dominated activities. Hairdressing and manufacturing work sectors were associated with the highest risk, showing the need to safeguard the health and safety of female workers.

Digital rehabilitation for hand and wrist pain: a single-arm prospective longitudinal cohort study

Supplemental Digital Content is Available in the Text.

This study supports that a fully remote digital care program is feasible and able to promote high patient engagement in the telerehabilitation of patients with wrist and hand pain.

Introduction:

Wrist and hand represent the third most common body part in work-related injuries, being associated with long-term absenteeism. Telerehabilitation can promote access to treatment, patient adherence, and engagement, while reducing health care–related costs.

Objective:

Report the results of a fully remote digital care program (DCP) for wrist and hand pain (WP).

Methods:

A single-arm interventional study was conducted on individuals with WP applying for a DCP. Primary outcome was the mean change in the Numerical Pain Rating Scale after 8 weeks (considering a minimum clinically important change of 30%). Secondary outcomes were: disability (Quick Disabilities of the Arm, Shoulder, and Hand questionnaire), analgesic intake, surgery intention, mental health (patient health questionnaire [PHQ-9] and generalized anxiety disorder [GAD-7]), fear-avoidance beliefs (FABQ-PA), work productivity and activity impairment, and engagement.

Results:

From 189 individuals starting the DCP, 149 (78.8%) completed the intervention. A significant pain improvement was observed (51.3% reduction (2.26, 95% CI 1.73; 2.78)) and 70.4% of participants surpassing minimum clinically important change. This change correlated with improvements in disability (52.1%), FABQ-PA (32.2%), and activities impairment recovery (65.4%). Improvements were also observed in other domains: surgery intent (76.1%), mental health (67.0% in anxiety and 72.7% in depression), and overall productivity losses (68.2%). Analgesic intake decreased from 22.5% to 7.1%. Mean patient satisfaction score was 8.5/10.0 (SD 1.8).

Conclusions:

These findings support the feasibility and utility of a fully remote DCP for patients with WP. Clinically significant improvements were observed in all health-related and productivity-related outcomes, alongside very high patient adherence rates and satisfaction. This study strengthens that management of WP is possible through a remote DCP, decreasing access barriers and potentially easing health care expenditure.

Carpal Tunnel Syndrome and Hand-Arm Vibration: A Swedish National Registry Case-Control Study

OBJECTIVE

To investigate the increased risk for carpal tunnel syndrome (CTS) in men and women with hand-arm vibration (HAV) exposure.

DESIGN

Case-control study of CTS where 4396 cases was obtained from National Outpatient Register between 2005 through 2016. Cases were matched to controls and exposure was estimated using a job exposure matrix.

RESULTS

Exposure to HAV increased the risk of CTS with an OR of 1.61 (95% CI 1.46-1.77). The risk was highest in men <30 years of age and among women <30 years no increased risk was observed. The risk increased with a mean year exposure above 2.5 m/s2 to OR 1.84 (95% CI 1.38-2.46).

CONCLUSIONS

HAV exposure increase the risk of CTS in both genders, with highest risk increase in younger men. This emphasize identification of HAV exposure in patients with CTS.

Reliability and validity of expert assessments of hand-wrist physical exposures

BACKGROUND

General population job-exposure matrices (JEMs) based on expert assessments of physical exposures may be valuable tools for studying occupation-related musculoskeletal disorders. Wrist-hand JEMs are few and the reliability and validity of expert assessments of wrist-hand exposures is uncertain.

METHODS

We examined intra- and inter-rater reliability of ratings of five experts of hand-wrist repetition, deviation, force, vibration, and computer work in 33 jobs selected to represent a large exposure variation. The validity of ratings of hand-wrist repetition was examined by comparison with electro-goniometer measurements of wrist angular velocity and mean power frequency (MPF), and the validity of hand-wrist deviation by comparison with goniometer measurements of range of motion (ROM).

RESULTS

Intra-rater test-retest and inter-rater Spearman correlation coefficients controlling for rater effects, varied between 0.70 and 0.87. Corresponding kappa statistics of overall agreement showed similar high values, except for wrist deviation (kappa = 0.50). Regression analyses showed strong positive associations between expert assessments of repetition and goniometer measurements of wrist angular velocity (R²  = 0.56, p < 0.0001) and MPF (R²  = 0.37, p < 0.0003), while expert ratings of wrist deviation showed a weak statistically nonsignificant association with goniometer measurements of ROM (R²  = 0.032, p = 0.34).

CONCLUSION

The reliability of expert assessments of wrist-hand physical exposures was high. Compared to goniometer measurements, the validity of assessments of wrist-hand repetition was also high, but it was low for assessments of wrist-hand deviation. The results are encouraging for establishing a hand-wrist JEM, but the results for wrist deviation emphasize that expert assessments should be validated against objective measurements.

Association of clinically relevant carpal tunnel syndrome with type of work and level of education: a general-population study

Carpal tunnel syndrome (CTS) is a common cause of work disability. The association with occupational load and education level has not been established in general-population studies. The purpose of this study was to investigate the association of clinically relevant CTS with work and education. From the Healthcare Register of Skane region (population 1.2 million) in southern Sweden we identified all individuals, aged 17–57 years, with first-time physician-made CTS diagnosis during 2004–2008. For each case we randomly sampled 4 referents, without a CTS diagnosis, from the general population matched by sex, age, and residence. We retrieved data about work and education from the national database. The study comprised 5456 individuals (73% women) with CTS and 21,667 referents. We found a significant association between physician-diagnosed CTS and type of work and level of education in both women and men. Compared with white-collar workers, the odds ratio (OR) for CTS among blue-collar workers was 1.67 (95% CI 1.54–1.81) and compared with light work, OR in light-moderate work was 1.37 (1.26–1.50), moderate work 1.70 (1.51–1.91), and heavy manual labor 1.96 (1.75–2.20). Compared with low-level education, OR for CTS in intermediate level was 0.82 (0.76–0.89) and high-level 0.48 (0.44–0.53). In women and men there is significant association with a dose–response pattern between clinically relevant CTS and increasing manual work load and lower education level. These findings could be important in design and implementation of preventive measures.

Repetitive and forceful movements of the hand as predictors of treatment for pain in the distal upper extremities

Objective

To investigate repetitive movements and the use of hand force as causes of treatment for distal upper extremities musculoskeletal disorders

Methods

A cohort of 202 747 workers in a pension health scheme from 2005 to 2017 in one of 17 jobs (eg, office work, carpentry, cleaning) was formed. Representative electro-goniometric measurements of wrist angular velocity as a measure for repetition and expert-rated use of hand force were used in a job exposure matrix (JEM). Job titles were retrieved from the Danish registers. Outcome was first treatment in the distal upper extremities. In a Poisson regression model, incidence rate ratios (IRRs) of treatment were adjusted for age, calendar-year, diagnosis of rheumatoid arthritis and arm fractures. In further analyses, wrist velocity or hand force was added.

Results

In men, wrist velocity had an IRR of 1.48 (95% CI 1.15 to 1.91) when the highest exposure level was compared with the lowest but with no clear exposure-response pattern. The effect became insignificant when adjusted for hand force. Hand force had an IRR of 2.65 (95% CI 2.13 to 3.29) for the highest versus the lowest exposure with an exposure-response pattern, which remained after adjustment for wrist velocity. Among women, no increased risk was found for hand force, while wrist velocity showed a significantly protective association with treatment.

Conclusions

In men, occupational exposure to hand force more than doubled the risk of seeking treatment. The results for exposure to repetition were less clear. In women, we could not find any indications of an increased risk neither for force nor for repetition.

Action Levels for the Prevention of Work-Related Musculoskeletal Disorders in the Neck and Upper Extremities: A Proposal

There are several well-known risk factors for work-related musculoskeletal disorders (MSDs). Despite this knowledge, too many people still work in harmful conditions. The absence of occupational exposure limits (OELs) for physical workload impedes both supervision and preventive work. To prevent myalgia, tendon disorders, and nerve entrapments in the upper musculoskeletal system, we propose action levels concerning work postures, movement velocities and muscular loads recorded by wearable equipment. As an example, we propose that wrist velocity should not exceed 20°/s as a median over a working day. This has the potential to reduce the prevalence of carpal tunnel syndrome (CTS) in highly exposed male occupational groups by 93%. By reducing upper arm velocity in highly exposed female groups to the suggested action level 60°/s, the prevalence of pronounced neck/shoulder myalgia with clinical findings (tension neck syndrome) could be reduced by 22%. Furthermore, we propose several other action levels for the physical workload. Our ambition is to start a discussion concerning limits for physical workload, with the long-term goal that OELs shall be introduced in legislation. Obviously, the specific values of the proposed action levels can, and should, be discussed. We hope that quantitative measurements, combined with action levels, will become an integral part of systematic occupational health efforts, enabling reduction and prevention of work-related MSDs.

Prevalence and risk factors of self-reported wrist and hand symptoms and clinically confirmed carpal tunnel syndrome among office workers in China: a cross-sectional study

Background

Carpal tunnel syndrome (CTS) is a common cause of pain, numbness and tingling in the wrist and hand region and is associated with repetitive wrist and hand use in office workers. However, scarce knowledge exists about the epidemiology of clinically confirmed CTS among Chinese office workers. This study aimed to investigate the prevalence of wrist/hand symptoms and CTS in office workers in China and to identify associated risk factors.

Methods

A cross-sectional survey was carried out in a metropolitan city in China involving 969 respondents (aged 17–49 years) from 30 workplaces. A questionnaire was distributed to each participant to collect their demographic, work-related physical and psychosocial factors, and wrist and hand symptoms. The wrist and hand pain/numbness symptoms were marked on a body chart and the nature and intensity of symptoms, nocturnal symptoms, as well as aggravating activities were also recorded. Clinically confirmed CTS cases were screened based on the history, Phalen’s test, Tinel Sign and skin sensation testing among symptomatic respondents. Logistic regression was employed to estimate the odds ratio (OR) and 95% confidence interval (95% CI) for the occurrence of self-reported wrist and hand symptoms and clinically confirmed CTS.

Results

The clinically confirmed CTS prevalence was 9.6%. The prevalence of wrist and hand symptoms were 22 and 15%, respectively. Frequently working in pain was associated with higher odds of CTS. Multivariate modelling adjusted for age and gender showed that prolonged computer use time and working without breaks were associated with presence of wrist/hand symptoms (adjusted ORs: 1.11 (95% CI 1.02–1.22) and 1.88 (95% CI 1.12–3.14)). Educational level was inversely associated with CTS and smoking was associated with wrist/hand complaints (adjusted OR: 2.20 (95% CI 1.19–4.07)).

Conclusions

The prevalence of work-related clinically confirmed CTS symptoms among young office workers in China is high. Frequently working in pain is closely associated with clinically confirmed CTS. Intense computer use and no breaks at work are associated with wrist and hand symptoms.

The impact of occupational and personal factors on musculoskeletal pain - a cohort study of female nurses, sonographers and teachers

Background

Musculoskeletal pain is common in the general population and constitutes a major public health problem. A large proportion of these conditions may be work related. The aim of this study was to explore the relative importance of physical, psychosocial and personal factors, in number of pain sites and in five specific pain sites, among women in common professions with a broad variety of occupational exposures.

Methods

A cohort of 1115 women responded to a questionnaire on ergonomic, psychosocial, personal and life-style factors, and the outcome measure of musculoskeletal pain (based on frequency and intensity of complaints at nine anatomical sites), at baseline and at follow-up. Sum scores of ergonomic and psychosocial factors were created. The importance of exposure at baseline for the number of pain sites at follow-up were estimated using ordinal regression. The importance of exposure at baseline for pain in the neck, shoulders, hands, lower back and feet at follow-up were estimated using multi-exposure Poisson regression models.

Results

High sum scores for ergonomic and psychosocial factors were of importance for a high number of pain sites, although the strongest risk factor was a high number of pain sites already at baseline. On the individual level, there was a large fluctuation in number of pain sites between the two time points. Eighteen percent reported persistent (or recurrent) ≥ four pain sites, while only 11 % did not report any pain at baseline or at follow-up. Among the specific pain sites, a high sum score of ergonomic factors was associated with pain in the neck, hands and feet. A high sum score of psychosocial factors was associated with neck and shoulder pain. The strongest risk factor was, however, pain at that specific anatomical site at baseline. Only a few of the personal and life-style factors were associated with pain.

Conclusions

An overwhelming majority of the women in common occupations were affected by musculoskeletal pain. Both ergonomic and psychosocial factors were predictive of a high number of pain sites and of specific pain sites. These findings indicate the need for preventive measures on the individual, organizational and societal level.

Proportion of upper extremity musculoskeletal disorders attributable to personal and occupational factors: results from the French Pays de la Loire study

BACKGROUND

Upper extremity musculoskeletal disorders (UEMSD) are one of the most common and costly occupational health problems. We aimed to assess the population-attributable fraction (PAF) of personal and occupational risk factors associated with incident UEMSD in a working population.

METHODS

From 2002 to 2005, a random sample of 3710 workers from the Pays de la Loire region in France, aged 20-59 were included by occupational physicians (OPs). Between 2007 and 2010, 1611 workers were re-examined by their OPs. Subjects free from UEMSD at baseline were included in this study (1275 workers, mean age: 38.2 years). Cox regression models with equal follow-up time and robust variance estimates were used to estimate age-adjusted and multivariable-adjusted relative risks (RRs) and their 95% confidence intervals (CIs). Based on multivariable models, PAF associated with each factor included in the models was estimated.

RESULTS

During the follow-up period, 143 (11%) cases of UEMSD were diagnosed. PAFs for factors associated with the incident UEMSD risk were 30% (7 to 51) for high physical exertion (RPE Borg scale ≥12), 12% (- 0.2 to 24) for low social support, 7% (- 3 to 17) for working with arms above shoulder level (≥2 h/day), 20% (12 to 28) for age group ≥45, 13% (3 to 22) for the age group 35-44, and 12% (0.3 to 24) for female gender.

CONCLUSIONS

Our study suggests that an important fraction of UEMSD can be attributed to occupational exposures after the contributions of personal and other work-related factors are considered. In terms of public health, our findings are in agreement with the ergonomic literature postulating that a high proportion of UEMSD are preventable through modifying workplace risk factors. Such information is useful to help public health practitioners and policy makers implement programs of prevention of UEMSD in the working population.

Biomechanical factors during common agricultural activities: Results of on-farm exposure assessments using direct measurement methods

Agricultural work is associated with increased risk of adverse musculoskeletal health outcomes. The purpose of this study was to quantify exposure to biomechanical factors among a sample (n = 55) of farmers in the Midwest region of the U.S. while they performed a variety of routine agricultural activities, and to compare exposure levels between these activities. Surface electromyography was used to estimate activity levels of the erector spinae, upper trapezius, forearm flexor, and forearm extensor muscle groups. Simultaneously, inertial sensors were used to measure kinematics of the trunk, upper arm, and wrist. In general, lower muscle activity levels, less extreme postures, and slower movement speeds were observed during activities that involved primarily the use of agricultural machinery in comparison to manual activities, suggesting a potential advantage of mechanization relative to musculoskeletal health. Median wrist movement speeds exceeding recently proposed exposure thresholds were also observed during many manual activities, such as milking animals and repairing equipment. Upper arm postures and movement speeds did not appear to confer excessive risk for shoulder-related outcomes (on the whole), but interpretation of the results is limited by a sampling approach that may not have captured the full extent of exposure variation. Not surprisingly, substantial variation in exposure levels were observed within each agricultural activity, which is related to substantial variation in the equipment, tools, and work practices used by participants. Ultimately, the results of this study contribute to an emerging literature in which the physical demands of routine agricultural work have been described on the basis of sensor-based measurements rather than more common self-report or observation-based approaches.

A Pilot Study of Five Types of Maximum Hand Strength among Manufacturing Industry Workers in Taiwan

Background: The purpose of this study is to collect five types of maximum hand strength among workers in the manufacturing industry in Taiwan. Methods: This study is a cross sectional study with a stratified and convenient sample of workers on the production line in manufacturing industries in Central Taiwan. In total, we recruited 198 healthy subjects to participate in this study. Five types of hand strength were measured in both hands three times with 3 min rests between trials. Results: The strength of females for these five types of hand exertions were 52.0% to 67.6% of the strength of males (p < 0.001). For both genders, there was a main effect for the types of hand strength for the right hand (p < 0.001) and the left hand (p < 0.001). In general, the hand strength in U.S. and EU countries was 1.2 to 1.7 times greater than the strength among the three types of hand exertions in this study. Conclusion: These results can be used to evaluate the musculoskeletal burdens on the upper extremities in the manufacturing industry and could also be used for tool and job design and job modifications.