Background: The aim of this study was to assess the associations between individual and occupational exposure factors and hospitalization for cervical disc disorder (CDD).
Methods: CDD was examined prospectively in a cohort of 278 319 Swedish male construction workers who participated in a national health surveillance program (1971-1993). Job title, smoking status, age, height, and weight were recorded on examination. Case data were obtained through linkage with the Swedish national in-patient hospital registry for the period 1987 – 2016; case status was defined by primary diagnosis code M50.0 (ICD-10) or 722.0, 722.4, or 722.7 (ICD-9). A job exposure matrix was developed and occupational exposure estimates were assigned by job title. Self-reported estimates of pain/discomfort from a subset of 87 500 workers were also linked to the database. Poisson regression models were used to estimate the relative risks (RR) for the biomechanical and self-reported factors with adjustment for smoking status, age, BMI and surgical time period.
Results: There were 562 cases of hospitalization for CDD; the incidence rate was 8.0 cases per 100 000 during the 29-year follow-up period. Smoking status, age, BMI and height were all associated with increased risk (RR 1.21-3.16). Occupational exposure to static work in non-neutral or extreme neck postures, and time spent in awkward postures showed the highest associations with CDD hospitalization (RR = 1.62 – 2.10). Upper arm load and time with arms above shoulders were also associated with increased risk (RR = 1.50 – 1.58). Workers who reported experiencing pain ‘often’ or ‘very often’ during the previous year for any of the neck, shoulder or upper back regions had a 3-fold increase in risk relative to workers reporting no pain.
Conclusions: Occupational non-neutral neck posture was associated with increased risk of hospitalization for CDD. Our data also suggest an exposure-response relationship for self-reported neck pain/discomfort and risk of hospitalization for CDD.