Natacha Fouquet

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.

Multidisciplinary Intensive Functional Restoration Versus Outpatient Active Physiotherapy in Chronic Low Back Pain A Randomized Controlled Trial

Study Design. Randomized parallel group comparative trial with a 1-year follow-up period. Objective. To compare in a population of patients with chronic low back pain, the effectiveness of a functional restoration program (FRP), including intensive physical training and a multidisciplinary approach, with an outpatient active physiotherapy program at 1-year follow-up. Summary of Background Data. Controlled studies conducted in the United States and in Northern Europe showed a benefit of FRPs, especially on return to work. Randomized studies have compared these programs with standard care. A previously reported study presented the effectiveness at 6 months of both functional restoration and active physiotherapy, with a significantly greater reduction of sick-leave days for functional restoration. Methods. A total of 132 patients with low back pain were randomized to either FRP (68 patients) or active individual therapy (64 patients). One patient did not complete the FRP; 19 patients were lost to follow-up (4 in the FRP group and 15 in the active individual treatment group). The number of sick-leave days in 2 years before the program was similar in both groups (180 ± 135.1 days in active individual treatment vs. 185 ± 149.8 days in FRP, P = 0.847). Results. In both groups, at 1-year follow-up, intensity of pain, flexibility, trunk muscle endurance, Dallas daily activities and work and leisure scores, and number of sick-leave days were significantly improved compared with baseline. The number of sick-leave days was significantly lower in the FRP group. Conclusion. Both programs are efficient in reducing disability and sick-leave days. The FRP is significantly more effective in reducing sick-leave days. Further analysis is required to determine if this overweighs the difference in costs of both programs.

Biomechanical constraints remain major risk factors for low back pain. Results from a prospective cohort study in French male employees

BACKGROUND CONTEXT Low back pain (LBP) is a major public health problem, with a considerable impact on workers. PURPOSE To model the risk of LBP in the male general working population. STUDY DESIGN/SETTING Repeated cross-sectional surveys in a wide occupational setting. PATIENT SAMPLE A random sample of 2,161 men working in various occupations in a French region participated in a first survey in 2002, and 1,313 of these (60.8%) participated in a second survey in 2007. OUTCOME MEASURE The self-reported prevalence of LBP during the previous week in the second survey. METHODS Twenty-one biomechanical, organizational, psychosocial, and individual factors were assessed in the first survey. The association between these potential risk factors and the prevalence of later LBP (in the second survey) was studied, using multistep logistic regression models. RESULTS Three hundred ninety-four men reported LBP in the second survey (prevalence 30.0%). The final multivariate model highlighted four risk factors: frequent bending (odds ratio [OR], 1.45, 95% confidence interval [CI], 1.07-1.97 for bending forward only; and OR, 2.13, 95% CI, 1.52-3.00 for bending both forward and sideways), driving industrial vehicles (OR, 1.35; 95% CI, 1.00-1.81), working more hours than officially planned (OR, 1.38; 95% CI, 1.05-1.81), and reported low support from supervisors (OR, 1.35; 95% CI, 1.02-1.79). CONCLUSIONS These results emphasize that biomechanical factors remain worth considering, even when psychosocial factors are taken into account, and provide a significant contribution to preventive strategies.

Incidence and risk factors for thoracic spine pain in the working population: the French Pays de la Loire study.

To examine the incidence and risk factors for incident thoracic spine pain (TSP) in workers representative of a French regions working population.

Prevalence of thoracic spine pain in a surveillance network

BACKGROUND Back pain has long been identified as a major occupational health issue, but there are few prevalence studies on thoracic spine pain (TSP). The epidemiological surveillance of musculoskeletal disorders implemented in 2002 by the French Institute for Public Health Surveillance in the Pays de la Loire region provided the opportunity to study the prevalence of TSP in a large, representative sample of workers. AIMS To assess the prevalence of TSP across a week in a regional workforce according to age, occupational category and industry sector in men and women separately. METHODS A random sample of workers aged 20-59 years, representative of the regional workforce, was constituted between 2002 and 2005. Medical and occupational data were gathered by questionnaire. RESULTS The sample consisted of 3710 workers (58% men). The prevalence of TSP was higher in women (17%) than in men (9%). Lower grade male white-collar workers were more likely to report TSP (17%) than male workers in other occupational categories, whereas upper grade female white-collar and professional workers were more likely to report TSP. No significant difference in the prevalence of TSP was noted in either men or women according to industry sector. CONCLUSIONS Although TSP is less frequent than low back and neck pain, the results of this study indicate that 1 in 10 men and 1 in 5 women suffer from TSP.

Chronic low back pain, chronic disability at work, chronic management issues

Low-back pain (LBP) stands out as the leading musculoskeletal disorder because it is both highly prevalent and the disability with which people live for the greatest number of years (1, 2). Reaching a peak between the ages of 30–50 years, LBP affects a population at a time of career advancement (3, 4). Back pain is the most expensive disease in terms of indirect costs due to sickness absence and work disability. Indirect (or productivity) costs contribute 93% to total costs, illustrating the importance of the consequences of the disease for work performance (5, 6). On a personal level, low self-motivation and self-confidence make it harder to initiate the return-to-work (RTW) process, especially when problems at work are related to the reason for sick leave (7, 8). At the workplace level, colleagues take over the tasks of the worker on sick leave, work piles up, or another worker is hired to take over the tasks. Timely RTW is thus of great benefit for both injured workers and their employers. The majority of people who experience an episode of back pain recover quickly without residual functional loss, and most of these episodes never reach the consulting room (9). Overall, it is estimated that 60–70% of patients recover within 6 weeks, and 80–90% within 12 weeks. However, recovery after 12 weeks is slow and uncertain, and fewer than half of individuals disabled >12 months return to work. After two years of absence from work, the RTW rate is close to zero (10): the longer a worker is unable to work, the greater is the probability that he/she will not return to work. Chronic LBP is not just “the same as acute back pain lasting longer”, but the result of a complex interplay of physical, psychological, social, and occupational factors. The World Health Organization’s International Classification of Functioning Disability and Health (ICF) has recognized the influence of personal and workplace factors on activity and participation levels (11). If the cause of work disability is associated with workplace factors, then a return to an unchanged workplace (with or without appropriate treatment for the disorder) may be not successful and even lead to recurrent sick leave of longer duration (12, 13). Personal and workplace factors may become RTW barriers. Management of chronic LBP thus has to take into account potential psychological and workplace RTW barriers that might hinder recovery. Key workplace factors include heavy physical demands, the inability to modify work, job stress, an unsupportive workplace, job dissatisfaction, poor expectation of RTW, and fear of re-injury (14). Key psychological factors include depressed mood, social isolation, pain catastrophizing, fear-avoidance beliefs, and low self-efficacy for managing pain (15). The recommendations for management of chronic LBP highlight the multidimensional nature of the problem. For example, the European guidelines for the management of chronic non-specific LBP recommend assessment of domains including work-related factors, psychosocial distress, and depressive mood, and point out that no single intervention is likely to be effective due to the multidimensional nature of chronic LBP (16). International guidelines therefore recommend the use of supervised active exercises, multidisciplinary approaches, cognitive-behavioral therapies, and measures of social and professional order for patients with chronic LBP (16–19). A number of exercise intervention trials for LBP have specifically targeted affected workers with the aim of facilitating a return to usual work or improving work endurance. An extensive literature review of randomized clinical trials for work conditioning programs among injured workers concluded that these types of programs were effective in reducing sick days for workers with chronic LBP compared to usual measures only when they: (i) integrated cognitive-behavioral approaches with intensive physical training (aerobic capacity, muscle strength and endurance, coordination); (ii) were in some way work-related; and (iii) were provided and supervised by either a physiotherapist or a multidisciplinary team (20). Although physical exercise can still be considered a beneficial and also a safe strategy for chronic LBP, the exact mechanisms are not yet clear and may be related to improved aspects of physical fitness, improved mood, fears and behavior, decreased sensitization, or combinations of these different mechanisms. Literature analysis suggests that it may be that including workplace visits or execution of the intervention at the workplace is the component that renders a physical conditioning program effective (21). According to a French study carried out in 2010 by the epidemiological surveillance network for musculoskeletal disorders in the Pays de la Loire region [3 601 113 inhabitants in 2014], the number of employees with LBP is very high. Using the macro Calmar, developed in SAS (SAS Institute, Cary, NC, USA) by the French National Institute of Statistics and Economic Studies (INSEE), the data from this network were extrapolated to the regional population covered by the occupational medicine (excluding some special social systems not represented in the study) to determine the extent of the phenomenon at the regional level (22). Thus, we can estimate that >268 000 employees reported backache during the preceding seven days and more than half a million (316 552 men and 244 253 women) during the 12 months preceding the survey (ie, 59.3% of men and 55.0% of women). Considering that 2–7% of people with non-specific LBP are at risk of developing chronic pain and disability in due course (23), this would indicate 11 216–39 257 employees at risk of developing severe and durable work disability. Given these statistics – and considering the recommended types of programs for chronic LBP, on the one hand, and the total amount of patient provision by multidisciplinary teams of rehabilitation centres on the other – it is obvious that we cannot meet requirements. These costly and time-consuming intensive multidisciplinary programmes can thus only be offered to a minority of the most heavily affected patients and therefore do not seem likely to respond to public health requirements (16, 18, 24). A lighter program may be one alternative strategy to full-time hospital-based programs at the same stage of treatment, with valuable results in terms of disability and occupational outcome for patients suffering from chronic LBP (24–30). More is not always better (31). It is therefore important to define both what the determining components of management are to overcome activity restriction, including occupational status, and how to include more hospital-independent programs in our healthcare systems in order to treat a larger number of patients more effectively at a lower cost and be able to offer stratified management programs adjusted to the severity of individual situations (32).

Carpal tunnel syndrome and computer exposure at work in two large complementary cohorts

Objectives The boom in computer use and concurrent high rates in musculoskeletal complaints and carpal tunnel syndrome (CTS) among users have led to a controversy about a possible link. Most studies have used cross-sectional designs and shown no association. The present study used longitudinal data from two large complementary cohorts to evaluate a possible relationship between CTS and the performance of computer work. Settings and participants The Cosali cohort is a representative sample of a French working population that evaluated CTS using standardised clinical examinations and assessed self-reported computer use. The PrediCTS cohort study enrolled newly hired clerical, service and construction workers in several industries in the USA, evaluated CTS using symptoms and nerve conduction studies (NCS), and estimated exposures to computer work using a job exposure matrix. Primary and secondary outcome measures During a follow-up of 3–5 years, the association between new cases of CTS and computer work was calculated using logistic regression models adjusting for sex, age, obesity and relevant associated disorders. Results In the Cosali study, 1551 workers (41.8%) completed follow-up physical examinations; 36 (2.3%) participants were diagnosed with CTS. In the PrediCTS study, 711 workers (64.2%) completed follow-up evaluations, whereas 31 (4.3%) had new cases of CTS. The adjusted OR for the group with the highest exposure to computer use was 0.39 (0.17; 0.89) in the Cosali cohort and 0.16 (0.05; 0.59) in the PrediCTS cohort. Conclusions Data from two large cohorts in two different countries showed no association between computer work and new cases of CTS among workers in diverse jobs with varying job exposures. CTS is far more common among workers in non-computer related jobs; prevention efforts and work-related compensation programmes should focus on workers performing forceful hand exertion.

An epidemiological surveillance network of lumbar disc surgery to help prevention of and compensation for low back pain

BACKGROUND In the context of the establishment of a new surveillance system, the aim was to assess the proportion of cases of lumbar disc surgery (LDS) attributable to work according to occupation category and industry sector. METHODS The sociodemographic and socioeconomic data of 3150 inpatients living in a French region discharged in 2007-2008 from spine centers of the region following LDS were compared with those of the regional population. Occupational history was gathered using a mailed questionnaire. The attributable fraction of risk for exposed individuals (AFE) and population attributable fraction of risk (PAF) were calculated in relation to occupations and industries. RESULTS Three occupational subcategories presented an AFE >50% for men (police and armed forces, unskilled agricultural and skilled craft blue-collar workers). There were eight subcategories for women, including material handlers and related equipment workers, and skilled industrial and unskilled agricultural blue-collar workers. The PAF for men was highest for construction and for women it was highest for wholesale and retail trades. CONCLUSION The AFE and PAF are valuable for public policy. Although PAF could be used to help public health policy makers to implement preventive measures, the AFE could assist expert tribunals who take decisions about compensation for occupational diseases.

Theoretical impact of simulated workplace-based primary prevention of carpal tunnel syndrome in a French region

BackgroundCarpal tunnel syndrome (CTS) is the most common nerve entrapment neuropathy in the working-age population. The reduction of CTS incidence in the workforce is a priority for policy makers due to the human, social and economic costs.To assess the theoretical impact of workplace-based primary interventions designed to reduce exposure to personal and/or work-related risk factors for CTS.MethodsSurgical CTS were assessed using regional hospital discharge records for persons aged 20–59 in 2009. Using work-related attributable fractions (AFEs), we estimated the number of work-related CTS (WR-CTS) in high-risk jobs. We simulated three theoretical scenarios of workplace-based primary prevention for jobs at risk: a mono-component work-centered intervention reducing the incidence of WR-CTS arbitrarily by 10% (10%-WI), and multicomponent global interventions reducing the incidence of all surgical CTS by 5% and 10% by targeting personal and work risk factors.ResultsA limited proportion of CTS were work-related in the region’s population. WR-CTS were concentrated in nine jobs at high risk of CTS, amounting to 1603 [1137–2212] CTS, of which 906 [450–1522] were WR-CTS. The 10%-WI, 5%-GI and 10%-GI hypothetically prevented 90 [46–153], 81 [58–111] and 159 [114–223] CTS, respectively. The 10%-GI had the greatest impact regardless of the job. The impact of the 10%-WI interventions was high only in jobs at highest risk and AFEs (e.g. food industry jobs). The 10%-WI and 5%-GI had a similar impact for moderate-risk jobs (e.g. healthcare jobs).ConclusionThe impact of simulated workplace-based interventions suggests that prevention efforts to reduce exposure to work-related risk factors should focus on high-risk jobs. Reducing CTS rates will also require integrated strategies to reduce personal risk factors, particularly in jobs with low levels of work-related risk of CTS.

0188 Thoracic spinal pain prevalence in the musculoskeletal disorders surveillance network of the French Pays de la Loire region

Objectives Prevalence studies of thoracic spinal pain (TSP) in the working population are scarce. The epidemiological surveillance of musculoskeletal disorders (MSDs), implemented in 2002 by the French Institute for Public Health Surveillance, allows the study of the prevalence of TSP in a large sample of workers. The aim of this study is to present the prevalence of TSP during the preceding 7 days in the Pays de la Loire region’s workforce according to age, combination with low back pain and neck pain, occupational category and industry sector, separately in men and women. Method A random sample of 3710 workers (58% of men) aged 20–59 years, representative of the regional workforce, was constituted between 2002 and 2005. Medical and occupational data were gathered by questionnaire. Results The prevalence of TSP was higher among women (17.4%) than men (9.2%), without age difference. Only 15.2% of TSP in men and 15.7% in women was declared without low back pain or/and neck pain. Among men, lower-grade white-collar workers were more likely to report TSP (16.6%) than other occupational categories workers (upper white-collar and professionals: 7.2%, technicians/associate professionals: 6.5%, blue-collar workers: 9.7%). Among women, upper white-collar and professionals were more likely to report TSP (25.6%) than the others (technicians/associate professionals: 17.0%, lower-grade white-collar workers: 17.1%, blue-collar workers: 16.7%). The study did not suggest a significant difference in the prevalence of TSP according to sectors in either men or women. Conclusions This study shows that, among workers, TSP is frequent and often combined with low back pain or neck pain.