Mechanical and psychosocial factors predict new onset shoulder pain: a prospective cohort study of newly employed workers.

AIM: To test the hypothesis that work related mechanical and psychosocial factors predict new onset shoulder pain in newly employed workers. METHODS: Two year prospective study of newly employed workers from 12 diverse occupational settings. At baseline, 1081 subjects provided information on work related mechanical and psychosocial risk factors, and current pain status. RESULTS: In all, 803 (74%) subjects were free from shoulder pain at baseline. Of those, 638 (79%) responded at 12 months and 476 (88%) at 24 months. New onset shoulder pain was reported by 93 (15%) and 73 (15%) subjects respectively. An increased risk of symptom onset was found in subjects reporting mechanical exposures involving heavy weights including lifting with one or two hands, carrying on one shoulder, lifting at or above shoulder level, and pushing or pulling. Working with hands above shoulder level was also predictive of new onset shoulder pain. Of the psychosocial factors examined, the strongest predictor was monotonous work. Those individuals with any other previous pain also had an increased risk of new onset shoulder pain at follow up. In multivariate analysis, lifting heavy weights with one or two hands, pushing or pulling heavy weights, working with hands above shoulder level, and monotonous work were independently associated with new onset shoulder pain. CONCLUSIONS: This study supports the hypothesised relation between mechanical risk factors and shoulder pain. In general, work related psychosocial factors were modestly associated with new onset shoulder pain. However, monotonous work was a strong risk factor for new onset shoulder pain.

Effects of psychosocial and individual psychological factors on the onset of musculoskeletal pain: common and site-specific effects.

OBJECTIVE: To determine whether adverse psychosocial and individual psychological factors increase the risk of pain across regional sites. METHODS: A prospective study was conducted of newly employed workers from 12 diverse occupational groups. Near to the beginning of subjects' employment, details of work related psychosocial factors and individual psychological distress were obtained by means of a self completed questionnaire. Questionnaire follow up after 12 months provided data on these same exposures and ascertained pain at any of four anatomical sites: the low back, shoulder, wrist/forearm, and knee. RESULTS: Of the original 1081 subjects, 829 (77%) provided full details at the one year follow up. Psychosocial work demands and high levels of individual psychological distress were found to have a common effect across sites. Psychological distress was associated with a doubling of the risk of reported pain (odds ratio = 2.1, 95% confidence interval 1.6 to 2.7), while aspects of job demand, poor support from colleagues, and work dissatisfaction were all associated with increased odds of reported pain onset of between 1.4 and 1.7. These effects were almost all common across the four regional pain sites. CONCLUSIONS: In cohorts of newly employed workers, certain work related psychosocial factors and individual psychological distress are associated with the subsequent reporting of musculoskeletal pain, and generally this effect is common across anatomical sites.

Risk factors for new-onset low back pain amongst cohorts of newly employed workers.

OBJECTIVES: To test the hypothesis that work-related mechanical, psychosocial and physical environment factors would predict new-onset low back pain (LBP) in newly employed workers. METHODS: A total of 1186 newly employed workers were recruited from a variety of occupational settings. Those who were free from LBP at baseline were identified. Subjects were followed up at 12 and 24 months. Work-related mechanical, psychosocial and physical environment exposures were measured. Generalized estimating equations were used to assess predictors of new-onset LBP. RESULTS: New-onset LBP was reported by 119 (19%) and 81 (19%) subjects at 12 and 24 months, respectively. Several work-related mechanical exposures predicted new-onset LBP including lifting heavy weights with one or two hands, lifting heavy weights at or above shoulder level, pulling heavy weights, kneeling or squatting for 15 min or longer. Of the psychosocial factors examined, stressful and monotonous work significantly predicted symptom onset. In addition, hot working conditions and pain at other sites also predicted new-onset LBP. On multivariate analysis these risks were only moderately attenuated but the 95% confidence intervals excluded unity only for the latter, non-mechanical, exposures. CONCLUSION: In this cohort of newly employed workers, from a range of occupations, several aspects of the work-place environment, other than mechanical factors, were important in predicting new-onset LBP. These results emphasize that interventions aimed at reducing the occurrence of LBP are likely to be most successful if they intervene across these domains.

The influence of work related psychosocial factors and psychological distress on regional musculoskeletal pain: a study of newly employed workers.

OBJECTIVE: To determine the influence of short term work related psychosocial factors (work demands, job control, and social support) and psychological distress on regional pain syndromes. METHODS: Newly employed workers were recruited from 12 occupational groups and information collected by questionnaire. Subjects indicated on a blank body manikin any low back, shoulder, wrist/forearm, or knee pain that had occurred during the past month and lasted more than one day. Data were also collected on work related psychosocial factors and on levels of psychological distress [using the General Health Questionnaire (GHQ)]. The relationships between psychosocial factors and psychological distress and each area of pain were calculated as odds ratios with 95% confidence intervals. Adjustment was made for age, sex, and occupational group. RESULTS: 1081 subjects (median age 23; interquartile range 20-27) were recruited to the study shortly after commencing employment: 261 (24%) reported low back pain, 221 (20%) reported shoulder pain, 93 (9%) reported wrist/forearm pain, and 222 (21%) reported knee pain. High levels of psychological distress were associated with increased likelihood of pain, with a trend observed between scores on the GHQ and the odds of pain in each of the 4 sites. Those who perceived their work as stressful most of the time were more likely to report back (OR 1.8, 95% CI 1.01-3.1) or shoulder pain (OR 1.9, 95% CI 1.02-3.4) than those who considered their work seldom stressful. Pace of work or job autonomy was less markedly related to pain at individual sites. Strong relationships were observed between psychological distress, job demands (stressful work, hectic work), low job control, and pain at multiple sites. CONCLUSION: The study has shown that adverse work related psychosocial factors, in particular aspects of job demand and control, influence the reporting of regional musculoskeletal pain. This occurs even after only short term exposure. The odds of reporting these adverse exposures are increased when pain is reported at multiple sites.

Short term influence of mechanical factors on regional musculoskeletal pain: a study of new workers from 12 occupational groups.

OBJECTIVES: To determine the influence of short term exposure to mechanical factors on regional musculoskeletal pain. METHODS: Full time newly employed workers were recruited from 12 occupational groups and information collected by questionnaire. Subjects indicated on a blank body manikin any low back, shoulder, wrist or forearm or both, or knee pain which had occurred during the past month and had lasted more than 1 day. Data were also collected with a previously validated questionnaire on working postures, manual handling activities, and repetitive movements of the upper limb. The relations between mechanical factors and each area of pain were calculated as odds ratios (ORs) with 95% confidence intervals (95% CIs). Adjustment was made for age and sex. RESULTS: 1081 subjects (median age 23; interquartile range 20--27) were recruited to the study (a participation rate of 91%). 261 (24%) reported low back pain, 221 (20%) shoulder pain, 93 (9%) wrist or forearm pain, and 222 (21%) knee pain. Several specific manual handling activities were found to be associated with low back, shoulder, and knee pain. Carrying weights of more than 50 lbs (23 kg) on one shoulder was the factor which was most strongly associated with low back pain (OR 2.4 (95% CI 1.5 to 3.8)), shoulder pain (OR 3.1 (95% CI 1.9 to 4.8)), and knee pain (OR 3.5 (95% CI 2.2 to 5.5)), whereas forearm pain was most strongly associated with repetitive movements of the wrists (OR 1.8 (95% CI 1.04 to 3.1)). By contrast very few postures were associated with regional pain, although bending forwards in an uncomfortable position for at least 15 minutes was associated with shoulder pain (OR 1.6 (95% CI 1.2 to 2.2)) and kneeling for at least 15 minutes was associated with knee pain (OR 1.8 (95% CI 1.2 to 2.6)). Exposure to mechanical factors was most strongly associated with pain at multiple sites rather than with pains in individual regions. CONCLUSIONS: Even among workers with only short term exposure to mechanical factors, musculoskeletal pain is increased.

The occurrence of falls among patients with a new episode of hip pain.

OBJECTIVES: To establish the risk of falling among those who consult their general practitioner with a new episode of hip pain and to discover if risk is altered by age and according to whether, at presentation, signs of osteoarthritis are present on radiography. METHODS: A case-control study was conducted. Cases were all patients who presented with a new episode of hip pain to participating general practices throughout the United Kingdom. All cases had a pelvic radiograph taken on recruitment to the study. Three controls were matched for sex, age, and general practice to each case. A questionnaire was sent by post to all cases and controls. The risk of having fallen in the past 12 months among cases and controls was compared. RESULTS: The study included 111 cases presenting with hip pain and 229 controls who had not consulted with hip pain in the previous 12 months. Women (odds ratio = 3.6, 95% CI 1.9, 6.7) but not men (odds ratio = 0.8, 95% CI 0.3, 2.3) reported an increased risk of falling in the previous 12 months. Similar results were obtained when the previous four months were considered. For all cases, hip pain predated any reported falls. The increased risk in women was found particularly for those aged less than 70. Risk of falling was not altered by the presence of radiological changes of osteoarthritis. CONCLUSIONS: Hip pain, which may be a symptom of osteoarthritis of the hip, increases the risk of falling. This finding has implications for the advice offered by general practitioners to patients who consult with early hip pain.

Interobserver reliability in measuring flexion, internal rotation, and external rotation of the hip using a plurimeter.

OBJECTIVE: To determine reliability of the measurement of hip movements (flexion, internal rotation, and external rotation) between medical practitioners. METHODS: Six clinicians carried out measurements of hip movements on each of six patients with osteoarthritis of one hip, using a specifically designed plurimeter. RESULTS: There was no evidence of any systematic difference between medical practitioners in the measurement of hip flexion, internal rotation, or external rotation. The degree of agreement was greatest for hip flexion. CONCLUSIONS: This study has shown that measurement of range of movement at the hip is repeatable between practitioners using a simple plurimeter and may represent an examination that is suitable for monitoring progress and treatment.