Occupational risk factors for surgically treated lumbar disc herniation - a 33-year follow-up.

Objectives: This study aimed to assess the associations between occupational biomechanical factors and occurrence of surgically treated lumbar disc herniation (LDH) and describe the consequences in terms of early exit from the labor market.

Methods: A cohort of 262 850 male construction workers participating in a national occupational health surveillance program was followed prospectively for 33 years (1987-2019). Occupational biomechanical exposures were assessed by a job exposure matrix (JEM) based on specific occupational groups. Workers who underwent surgical treatment for LDH were identified from the national patient register and data on disability pension from the Swedish Social Insurance Agency. Poisson regression models were used to estimate relative risks (RR) and 95% confidence intervals (CI) for biomechanical exposures, adjusted for age, body mass index, smoking status, height and time period.

Results: There were 2451 cases of surgical treatment for LDH and the incidence peaked at age 40-45 years. Increased risks were found for often lifting >25 kg (RR 1.77, 95% CI 1.06-2.94), extreme lumbar flexion/extension (RR 1.60, 95% CI 1.37-1.88) and high exposure to whole-body vibration (RR 1.32, 95% CI 1.05-1.65). Among cases, the mean age for exiting the labor market due to disability pension was 55.9 years for white-collar workers and 51.7 years for construction workers.

Conclusions: Occupational exposure to heavy lifting and working in non-neutral back postures was associated with increased risk of surgical treatment for LDH. Construction workers who have had surgery for LDH exited the labor market with disability pension earlier than white-collar workers.