ECK DISORDERS REMAIN A common problem in modern, industrialized countries. Neck pain has been the most common chief complaint among working-aged women visiting their physicians. 1,2 In a Canadian study, 3 54% of the general population had experienced neck pain during the past 6 months, and approximately 5% were highly disabled by neck pain. The prevalence of chronic neck pain has been reported to be 7% in women and 5% in men in Finland. 4 Patients with chronic neck pain used health care services twice as much as the population on average. 2 Sick leave, therapy, and specialist care form the major part of the costs incurred by neck pain, whereas investigations at the primary health care level play a minor role. 5 The origin and exact pathophysiologic mechanisms of chronic neck pain often remain obscure because trauma or severe degenerative conditions at working age are found only in Author Affiliations are listed at the end of this article.

Objectives This systematic review aimed to identify published observational methods assessing biomechanical exposures in occupational settings and evaluate them with reference to the needs of different users. MethodsWe searched scientific databases and the internet for material from 1965 to September 2008. Methods were included if they were primarily based on the systematic observation of work, the observation target was the human body, and the method was clearly described in the literature. A systematic evaluation procedure was developed to assess concurrent and predictive validity, repeatability, and aspects related to utility. At least two evaluators independently carried out this evaluation. ResultsWe identified 30 eligible observational methods. Of these, 19 had been compared with some other method(s), varying from expert evaluation to data obtained from video recordings or through the use of technical instruments. Generally, the observations showed moderate-to-good agreement with the corresponding assessments made from video recordings; agreement was the best for large-scale body postures and work actions. Postures of wrist and hand as well as trunk rotation seemed to be more difficult to observe correctly. Intra-and inter-observer repeatability were reported for 7 and 17 methods, respectively, and were judged mostly to be moderate or good.good. . ConclusionsWith training, observers can reach consistent results on clearly visible body postures and work activities. Many observational tools exist, but none evaluated in this study appeared to be generally superior. When selecting a method, users should define their needs and assess how results will influence decision-making.

Objectives-To evaluate the eVects of work related and individual factors as well as physical activity and sports on the incidence and persistence of shoulder pain among forestry workers. Methods-Workers in a large Finnish forestry company replied to a questionnaire (a modified version of the Nordic questionnaire) on musculoskeletal pain and its possible risk factors for 4 consecutive years 1992-5. This 1 year follow up study covers the time 1994-5. Year 1994 was chosen as baseline because in that year the questionnaire contained for the first time more detailed questions about diVerent sports. The response rate in 1995 was 90%. The eVects of the predictors on 1 year incidence and persistence of shoulder pain were studied with multivariate logistic regression modelling. Results-At baseline, 2094 subjects had been free of shoulder pain during the preceding 12 months. After 1 year, 14% (n=285) reported having mild or severe shoulder pain. Higher age, obesity, and mental stress as well as physically strenuous work and working with trunk forward flexed or with a hand above shoulder level increased the risk of incident shoulder pain. Of the diVerent sports activities, dancing increased the risk of incident pain whereas jogging decreased the risk significantly. Of those 419 workers who had severe shoulder pain at baseline, 55% (n=230) still had severe pain 1 year later. Higher age, overload at work, and working with a hand above shoulder level increased the risk of persistent severe shoulder pain whereas cross country skiing and general sports activity decreased the risk. Conclusion-Our results support the current view that shoulder pain is the result of many factors, including occupational and individual factors. In this longitudinal study, physical work with a heavy load, awkward work postures, mental stress, and obesity were the risk factors at which preventive measures could be aimed. As a new finding, physical exercise had more protective than impairing eVects on the shoulders. (Occup Environ Med 2001;58:528-534) Keywords: mental stress; physical work load; sportsThe prevalence of shoulder symptoms seems to be relatively high, varying from 6% to 25% in the general population.1 2 During the past decades, the knowledge of aetiological factors, and occupational exposures in particular, has increased and work related factors such as repetitive work, vibration, and awkward postures-for example, severe shoulder flexion or abduction-have been related to shoulder disorders.1 3 4 Other factors such as age, smoking, and stress have been significant risk factors in some studies. [5][6][7] This knowledge is, however, mainly based on studies with cross sectional or case-control design. In a recent systematic review of the available evidence on occupational risk factors for shoulder pain, no longitudinal studies fulfilled the quality criteria. As well as prospective studies, more studies of the eVects of leisure time activities were called for.

Objectives This study assessed the validity of self-reported physical work load by questionnaire and logbook against task analysis and observation. It also investigated factors (job type and low-back or neck pain) affecting the self-assessment of physical work load and compared the assessments between the questionnaire and the logbook.Methods A self-administered questionnaire including 10 questions (ordinal scales) on physical work load and musculoskeletal symptoms was filled out by 2756 men in the forest industry. From this population, 36 men were selected for task analysis and observation. Logbooks including 10 continuous variables were analyzed for 386 men. ResultsThe Spearman rank correlation coefficients between the self-assessments and observations for the frequency of manual handling, duration of trunk flexion, neck rotation, hand above shoulder level, and squatting or kneeling ranged between 0.42 and 0.55. The correlation coefficients for the questionnaire items were higher in general, and the accuracy better, for those with no low-back pain than for those with pain. The duration of trunk flexion, neck flexion and hand above shoulder level was overestimated in the questionnaires and less so in the logbooks.Conclusions Self-administered questionnaires may help to classify groups with heterogeneous occupational tasks according to some work-load factors. The accuracy of the assessments is not good for studying quantitative exposure-effect relationships, however. The logbook method might give more valid information. The perception of musculoskeletal pain may bias the self-assessment of work load.

The findings from this study suggest that mental stress and smoking are independent risk factors for incidental sciatic pain. Overall physical exercise and most of the sports activities, except jogging and walking, had no effect on sciatic pain. Physical workload factors seemed to be more involved in the onset of sciatic pain, whereas psychosocial factors were related to the persistence of symptoms.