Catherine Ha

Risk factors for upper-extremity musculoskeletal disorders in the working population.

OBJECTIVE To assess the relative importance of personal and occupational risk factors for upper-extremity musculoskeletal disorders in the working population. METHODS A total of 3,710 workers (58% men) participating in a surveillance program of musculoskeletal disorders in a French region in 2002-2005 were included. Upper-extremity musculoskeletal disorders were diagnosed by 83 trained occupational physicians performing a standardized physical examination. Personal factors and work exposure were assessed by a self-administered questionnaire. Statistical associations between musculoskeletal disorders, personal, and occupational factors were analyzed using logistic regression modeling. RESULTS A total of 472 workers experienced at least 1 upper-extremity musculoskeletal disorder. The risk of upper-extremity musculoskeletal disorders increased with age for both sexes (P < 0.001, odds ratio [OR] < or =4.9 in men and < or =5.0 in women), and in cases of prior history of upper-extremity musculoskeletal disorders (OR 3.1 and 5.0, respectively, P < 0.001). In men, upper-extremity musculoskeletal disorders were associated with obesity (OR 2.2, P = 0.014), high level of physical demand (OR 2.0, P < 0.001), high repetitiveness of the task (OR 1.5, P = 0.027), postures with the arms at or above shoulder level (OR 1.7, P = 0.009) or with full elbow flexion (OR 1.6, P = 0.006), and high psychological demand (OR 1.5, P = 0.005). In women, upper-extremity musculoskeletal disorders were associated with diabetes mellitus (OR 4.9, P = 0.001), postures with extreme wrist bending (OR 2.0, P < 0.001), use of vibrating hand tools (OR 2.2, P = 0.025), and low level of decision authority (OR 1.4, P = 0.042). CONCLUSION Personal and work-related physical and psychosocial factors were strongly associated with clinically diagnosed upper-extremity musculoskeletal disorders.

Why are manual workers at high risk of upper limb disorders? The role of physical work factors in a random sample of workers in France (the Pays de la Loire study).

Objective: To investigate the reasons for the excess risk of upper limb musculoskeletal disorders among manual workers compared with other workers in a random sample of 2656 French men and women (20–59 years old) participating in a study on the prevalence of work related upper limb disorders conducted by France’s National Institute of Health Surveillance. Methods: Prevalence ratios (PR) of physician-diagnosed musculoskeletal disorders of the shoulder, elbow, wrist, and hand (any of six leading disorders, rotator cuff syndrome, carpal tunnel syndrome) in manual versus non-manual workers were calculated using Cox regression models with a constant time of follow up and robust variance. Results: 11.3% of men and 15.1% of women were diagnosed with an upper limb disorder. The risk was especially high in manual workers (PRs: 1.40 to 2.10). Physical work factors accounted for over 50% of occupational disparities overall, 62% (men) to 67% (women) for rotator cuff syndrome, and 96% (women) for carpal tunnel syndrome. The authors calculated that under lower levels of physical work exposures, up to 31% of cases among manual workers could have been prevented. Conclusions: In working men and women, upper limb musculoskeletal disorders are frequent. Physical work exposures, such as repetitive and forceful movements, are an important source of risk and in particular account for a large proportion of excess morbidity among manual workers.

Work increases the incidence of carpal tunnel syndrome in the general population

The purpose of this study was to estimate the incidence of carpal tunnel syndrome (CTS) in a general population according to employment status and to assess the proportion of cases attributable to work. CTS occurring in patients aged 20–59 years living in the French Maine and Loire region were included prospectively from 2002 to 2004. Medical and occupation history was gathered by mailed questionnaire. Incidence rates of CTS and relative risks (RRs) of CTS were computed in relation to employment status. The attributable fractions of risk of CTS to work among the exposed persons (AFEs) were calculated. A total of 1168 patients (819 women, 349 men) were included during the 3‐year period. The mean incidence rate of CTS per 1000 person‐years was higher in employed than unemployed persons (1.7 vs. 0.8 in women and 0.6 vs. 0.3 in men). The excess risk of CTS was statistically significant for male (RR 4.2) and female (RR 3.0) blue‐collar workers and female lower‐grade white‐collar workers (RR 2.5). The AFE to work in general was 47% (95% confidence interval: 39–54) in women. AFEs reached higher values in female blue‐collar workers [67% (65–68)] and lower‐grade services, sales, and clerical white‐collar workers [61% (57–64)]. The AFE in male blue‐collar workers was 76% (72–80). These data show a higher incidence of CTS in the working than the non‐working population and suggest that a substantial proportion of CTS cases diagnosed in lower‐grade white‐collar and blue‐collar workers are attributable to work. Muscle Nerve, 2008

The French Musculoskeletal Disorders Surveillance Program: Pays de la Loire network

Objectives: An epidemiological surveillance system for work-related musculoskeletal disorders (MSDs) was implemented in 2002 in France’s Pays de la Loire region to assess the incidence and prevalence of MSDs in the general and working populations, identify levels of exposure to occupational risk factors and investigate the proportion of cases attributable to work exposure. Methods: The program combines (1) surveillance of sentinel health events in the general population (carpal tunnel syndrome (CTS) was the sentinel event for upper limb MSDs), (2) assessment of the prevalence of the main upper limb MSDs and their risk factors in the workplace based on a network of occupational physicians and (3) registration of the notification of work-related diseases (WRDs). Results: 1168 incident cases of CTS were included over a 3 year period. The estimated incidence of CTS was 1.00 per 1000 person-years in those aged 20–59 years (0.60 in men and 1.40 in women). The incidence rate was higher in employed than unemployed persons in the year of diagnosis (0.6 per 1000 vs 0.3 in men and 1.7 vs 0.8 in women). The occupational physician network noted high prevalence rates: 11% of men and 15% of women had at least one of the six main upper limb clinically-diagnosed MSDs. The WRD survey showed that MSDs represented 65% of notified WRDs. Conclusion: The Pays de la Loire program plays a significant role in informing the authorities and the public about the state of current MSDs. It is planned to extend it to a routine national surveillance program.

Risk factors for incidence of rotator cuff syndrome in a large working population.

OBJECTIVES The aim of this study was to assess the effects of personal and work-related factors on the incidence of rotator cuff syndrome (RCS) in a large working population. METHODS A total of 3710 French workers were included in a cross-sectional study in 2002-2005. All completed a self-administered questionnaire about personal factors and work exposure. Using a standardized physical examination, occupational physicians established a diagnosis of RCS. Between 2007-2010, 1611 workers were re-examined. Associations between RCS and risk factors at baseline were analyzed by logistic regression. RESULTS A total of 839 men and 617 women without RCS at baseline were eligible for analysis. RCS was diagnosed in 51 men (6.1%) and 45 women (7.3%). The risk of RCS increased with age for both genders [odds ratio (OR) 4.7 (95% confidence interval [95% CI] 2.2-10.0) for men aged 45-49 years and 5.4 (95% CI 2.3-13.2) for women aged 50-59 years; reference <40 years]. For men, the work-related risk factors were repeated posture with the arms above the shoulder level combined with high perceived physical exertion [OR 3.3 (95% CI 1.3-8.4)] and low coworker support [OR 2.0 (95% CI 1.1-3.9)]. For women, working with colleagues in temporary employment [OR 2.2 (95% CI 1.2-4.2)] and repeated arm abduction (60-90°) [OR 2.6 (95% CI 1.4-5.0)] were associated with RCS. CONCLUSIONS Age was the strongest predictor for incident cases of RCS, and arm abduction was the major work-related risk factor for both genders. Lack of social support was a predictor for RCS among men.

Attributable risk of carpal tunnel syndrome according to industry and occupation in a general population.

OBJECTIVE An epidemiologic surveillance network for carpal tunnel syndrome (CTS) was set up in the general population of a French region to assess the proportion of CTS cases attributable to work in high-risk industries and occupations. METHODS Cases of CTS occurring among patients ages 20-59 years living in the Maine and Loire region were included prospectively from 2002 to 2004. Medical and occupation history was gathered by mailed questionnaire for 815 women and 320 men. Age-adjusted relative risks of CTS and the attributable risk fractions of CTS among exposed persons (AFEs) were computed in relation to industry sectors and occupation categories. RESULTS Twenty-one industry sectors and 8 occupational categories for women and 10 sectors and 6 occupational categories for men were characterized by a significant excess risk of CTS. High AFE values were observed in the manufacturing (42-93% for both sexes), construction (66% for men), and personal service industries (66% for women) and in the trade and commerce sectors (49% for women). High AFE values were observed in lower-grade white-collar occupations for women (43-67%) and blue-collar occupations for men (60-74%) and women (48-88%). CONCLUSION The attributable proportions of CTS cases among workers employed in industry sectors and occupation categories identified at high risk of CTS varied between 36% and 93%.

Effects of Individual and Work-related Factors on Incidence of Shoulder Pain in a Large Working Population

Effects of Individual and Work‐related Factors on Incidence of Shoulder Pain in a Large Working Population: Julie BODIN, et al. LUNAM Université, Université d’Angers, Laboratoire d’ergonomie et d’épidémiologie en santé au travail (LEEST), France—

Prevalence of multisite musculoskeletal symptoms: a French cross-sectional working population-based study

BackgroundThe musculoskeletal disorders in working population represent one of the most worrying work-related health issues at the present time and although the very great majority of available data on the subject focus on musculoskeletal disorders defined by anatomical site, a growing number of studies indicate the low prevalence of disorders strictly confined to a specific anatomical site. The objective of this study was to describe the prevalence and characteristics of multisite musculoskeletal symptoms (multisite MS) in a large French working population.MethodsThis study was performed on surveillance data of the cross-sectional survey (2002–2005) conducted by a network of occupational physicians in the working population of the Loire Valley region (from 20 to 59 years old). Data concerning MS were collected in the waiting room of the occupational physicians by means of the self-administrated standardized NORDIC questionnaire.ResultsThe study population comprised 3,710 workers (2,162 men (58%) and 1,548 women (42%)) with a mean age of 38.4 years (standard deviation: 10.4 years). The prevalence of MS during the past 12 months was 83.8% with 95% confidence interval of [82.8-85.3] for men and 83.9% [82.0-85.7] for women. The prevalence of subacute MS (lasting at least 30 days) over the past 12 months was 32.8% [30.9-34.8] for men and 37.3% [34.9-39.7] for women. Two-thirds of workers reported MS in more than one anatomical site and about 20% reported MS lasting at least 30 days in more than one anatomical site. The anatomical sites most frequently associated with other MS were the upper back, hip, elbow and neck. The majority of these multisite MS were widespread, involving at least two of the three anatomical regions (upper limb, axial region and lower limb).ConclusionsThe frequency and extent of multisite MS reported by workers are considerable. Further research must be conducted in this field in order to provide a better understanding of the characteristics and determinants of these multisite MS.

Personal, biomechanical, and psychosocial risk factors for rotator cuff syndrome in a working population.

OBJECTIVE Rotator cuff syndrome (RCS) is a major health problem among workers. The aim of the study was to examine the risk factors for RCS among workers exposed to various levels of shoulder constraints. METHODS From 3710 workers, representative of a French region`s working population, trained occupational physicians diagnosed a total of 142 cases of RCS among men and 132 among women between 2002-2005. Diagnoses were established by standardized physical examination while personal factors and work exposure were assessed by self-administered questionnaires. Statistical associations between RCS and personal and work-related factors were analyzed for each gender using logistic regression modeling. RESULTS The personal risk factors for RCS were age [odds ratio (OR) for 1-year increment 1.07, 95% confidence interval (95% CI) 1.05-1.09, among men and 1.08, 95% CI 1.06-1.10, among women] and diabetes mellitus (OR 2.9, 95% CI 1.0-8.6, among women). The work-related risk factors were (i) sustained or repeated arm abduction (≥ 2 hours/day) >90 degrees among men (OR 2.3, 95% CI 1.3-3.9) and >60 degrees among women (OR 1.8, 95% CI 1.0-3.2) or both conditions among men (OR 2.0, 95% CI 1.1-3.7) and women (OR 3.6, 95% CI 1.8-7.3); (ii) high repetitiveness of the task (≥ 4 hours/day) among men (OR 1.6, 95% CI 1.0-2.4) and women (OR 1.7, 95% CI 1.1-2.5); (iii) high perceived physical demand among men (OR 2.0, 95% CI 1.3-3.1); (iv) high psychological demand among men (OR 1.7, 95% CI 1.2-2.5); and (v) low decision authority among women (OR 1.5, 95% CI 1.0-2.3). CONCLUSION Personal (ie, age) and work-related physical (ie, arm abduction) and psychosocial factors were associated with RCS for both genders in this working population.

Work-related risk factors for incidence of lateral epicondylitis in a large working population

OBJECTIVES This study aims to estimate the association between repeated measures of occupational risk factors and the incidence of lateral epicondylitis in a large working population. METHODS A total of 3710 workers in a French region were included in 2002-2005, and among them 1046 had a complete follow-up in 2007-2010. At both stages, occupational health physicians assessed the presence of lateral epicondylitis and workers self-reported their occupational exposures. Poisson models were performed to assess the incidence rate ratios (IRR) separately by sex using multiple imputed data. RESULTS The annual incidence rate of lateral epicondylitis was estimated as 1.0 [95% confidence interval (95% CI) 0.7-1.3] per 100 workers among men and 0.9 (95% CI 0.6-1.3) among women. Workers aged >45 years had higher incidence than those aged <30 years (significant at 10%). Among men, high physical exertion combined with elbow flexion/extension or extreme wrist bending (>2 hours/day) was a risk factor, with an age-adjusted IRR of 3.2 (95% CI 1.5-6.4) for workers exposed at both questionnaires [3.3 (95% CI 1.4-7.6) among women]. CONCLUSIONS This study highlights the importance of temporal dimensions for occupational risk factors on the incidence of lateral epicondylitis. Further research should evaluate the risk associated with the duration and repetition of occupational exposure on the incidence of lateral epicondylitis.