Abstract
Musculoskeletal disorders (MSDs) among workers can lead to substantial personal, financial and societal costs. MSDs have a high prevalence among nurses, postal workers and office workers yet, at many anatomical sites, little is known about the incidence, impact and risk factors for MSDs among these workers. This mixed methods inquiry investigated the occurrence, risk factors, impacts and outcomes of MSDs in these New Zealand workers.
A longitudinal cohort postal survey was administered in 2007 with follow-up one year later. This was the New Zealand arm of the international CUPID (Cultural and Psychosocial Influences on Disability) study, with New Zealand additions to the questionnaire. The survey consisted of questions about demographic aspects, MSDs of the low back, neck, shoulder, elbow, wrist/hand and knee, work-related physical and psychosocial aspects and psychological factors. Face-to-face qualitative interviews were undertaken with a selection of participants (n=14) who had reported an MSD in the follow-up postal survey. The in-depth interviews aimed to explore 1) the experience of having an MSD and 2) the design and content of the postal surveys.
The postal survey baseline participation rate postal survey was 58% (n=443); the follow-up rate was 87% (n=384). Overall, the twelve month cumulative incidence of MSDs was 11-30%, depending on the anatomical site. Postal workers (43%) had a higher incidence of wrist/hand pain compared to nurses (18%) and office workers (17%). After adjusting for potential confounding factors, job insecurity was associated with low back pain (LBP) incidence (OR 2.03, 95% CI 1.05, 3.90). Greater somatising tendency (OR 2.79, 95% CI 1.26, 6.17) and high job demands (OR 2.75, 95% CI 1.38, 5.46) were associated with wrist/hand pain incidence and non-permanent contracts (OR 3.87, 95% CI 1.63, 9.19), ‘reaching, pushing or pulling’ (OR 2.48, 95% CI 1.01, 6.07) and higher social support (OR 0.39, 95% 0.17, 0.92) were associated with knee pain incidence. Of MSDs reported in the baseline survey, 42-72% were also reported in the follow-up at twelve months. Greater baseline expectations of future problems were associated with persistent/recurrent LBP; non-permanent contracts were associated with persistent/recurrent neck pain. Overall, the twelve month prevalence of MSDs involving time off work or modified duties was 4-14%, depending on the anatomical site. Nurses (20%) and postal workers (18%) had a higher prevalence of LBP affecting work than office workers (4%); postal workers had the highest prevalence of shoulder (17%) and wrist/hand pain (18%). The one-month prevalence of MSDs affecting functional tasks was 5-16%, depending on the anatomical site.
A substantial proportion of MSDs were not reported to healthcare providers; findings from the qualitative study suggest complex influences affect whether healthcare providers are consulted. Flexibility was a key attribute of work (and the workplace) suggested as helpful for those with MSDs. Recommendations for future postal surveys highlight the need for clear communication throughout the survey process.
This study demonstrates that a substantial number of MSDs are occurring at a range of anatomical sites in these New Zealand workers. High proportions are persistent or recurrent. Risk factors are multi-factorial but include potentially modifiable factors.