Are forward bending of the trunk and low back pain associated among Danish blue-collar workers? A cross-sectional field study based on objective measures

• Published in: Ergonomics 2015-02, Vol.58 (2), p.246-258
• Main Authors: Villumsen, Morten, Samani, Afshin, Jørgensen, Marie Birk, Gupta, Nidhi, Madeleine, Pascal, Holtermann, Andreas
• Format: Article
• Language: English
• Subjects: accelerometry; Adult; Back pain; Bending; Blue collar workers; body posture; Categories; Correlation analysis; Cross sections; Cross-Sectional Studies; Denmark - epidemiology; Diagnostic Self Evaluation; diurnal measurements; Ergonomics; Female; Field study; Humans; inclination; Lifting - adverse effects; Logistic Models; Logistics; Low Back Pain - epidemiology; Low Back Pain - etiology; Low Back Pain - physiopathology; Male; Middle Aged; Movement; musculoskeletal disorders; Occupational Diseases - epidemiology; Occupational Diseases - etiology; Occupational Diseases - physiopathology; Pain; Pain Measurement; Posture; Prevalence; Risk Factors; Space life sciences; Torso - physiopathology; Trunks; Work - physiology; Workload
• ISSN: 0014-0139; 1366-5847
• DOI: 10.1080/00140139.2014.969783

The aim of this cross-sectional study was to investigate the association between the duration of objectively measured forward bending of the trunk and low back pain (LBP) intensity among 198 Danish blue-collar workers (male = 115; female = 83). The duration of forward bending of ≥ 30°, ≥ 60° and ≥ 90° was divided into high (the highest tertile) and low-moderate (the remaining tertiles) categories. High (>5) and low ( ≤ 5) pain intensities were categorised from a self-reported 0-9 scale. Results of multi-adjusted logistic regressions indicated no significant positive associations between forward bending and LBP intensity. On the contrary, higher duration of forward bending of ≥ 30° was associated with lower LBP intensity during all day (OR = 0.40; 95% CI, 0.15-1.02; p = 0.05) and work (OR = 0.44; 95% CI, 0.17-1.15; p = 0.09). This indication of a negative association may be explained by fear-avoidance behaviour of the blue-collar worker, job crafting or healthy worker effect. Practitioner Summary: Ergonomics practice often relies on observations and subjective assessments. This study indicates that higher duration of forward bending of the trunk may be associated with lower low back pain intensity among blue-collar workers. Therefore, practitioners should take care in basing recommendations for action on concurrent measures of workload and pain.