Background: Back pain (including neck pain) is one of the most prevalent health problems for which physicians are consulted. Back pain can decrease the quality of life considerably during a great part of the lives of those who suffer from it. At the same time it has an enormous economic impact, mainly through sickness absence and long-term disability. The objective of this paper is to compare the incidence of occupational disability as a result of back and neck pain in 1980-1985 to 1999-2000 and to explain the findings. Methods: A descriptive study was performed at population level of changes in incidence of occupational disability as a result of back and neck pain. Statistics from the National Institute of Social Insurance in the Netherlands are used to calculate age and gender specific incidence rates for back pain diagnoses based on the ICD-classification. Incidence rate ratios stratified according to gender and adjusted for age were calculated to indicate changes over time. Results: The incidence of occupational disability as a result of back pain decreased significantly by 37% (95% CI 37%-38%) in men and with 21% (95% CI 20%-24%) in women, after adjustment for age. For overall occupational disability as a result of all diagnoses this was 18% (95% CI 18%-19%) and 34% (95% CI 33%-35%) respectively. Changes were not homogeneous over diagnostic subcategories and age groups. Spondylosis decreased most in men by 59% (95% CI 57%-61%). The incidence of non-specific back pain and neck pain increased most by 196% (95% CI 164%-215%). Post-laminectomy syndrome increased over all age categories both for men (85%, 95% CI 61%-113%) and women (113%, 95% CI 65%-179%). Conclusion: The decrease in occupational disability as a result of back pain was larger than the decrease in occupational disability over all diagnoses. However, time trends were not homogeneous over age-, nor over sex- nor back pain categories. Most of this decrease was due to general changes such as legal and economic changes. One of several additional explanations for a decrease is the changed view on management of back pain. © 2006 Steenstra et al; licensee BioMed Central Ltd.