Population requirements for primary hip-replacement surgery in England A comparison with knee-replacement

The debate about health care rationing, in terms of both its justification and mechanism, is conducted largely in the absence of data. The relevant literature mainly consists of assertion, exploration of ethical principles and political analysis. In particular, an epidemiological basis for the assumption that demand for effective treatments will invariably exceed supply is lacking. Waiting list figures suggest that health services are not satisfying demand in particular areas, but this does not mean that demand is generally insatiable. Total hip and knee replacements are effective interventions for patients with severe joint disease, resulting in large improvements in patient-related outcome measures for the majority of those undergoing these procedures. Although the number of operations performed in England has been rising each year over the last two decades [1], it has been suggested that there is still a large unmet need. However, the current evidence base is limited. Some prevalence data on severe joint disease in the community are available [2], but incidence data to estimate the annual population requirement for hip and knee replacement are lacking. Consensus criteria for case selection for total joint replacement (TJR) have been published [3, 4], but data on the impact of these criteria on annual rates are unavailable, and the implications of different thresholds for surgery, patient preference and other modifiers of the decision to recommend surgery are unclear. © 2009 Springer-Verlag Berlin Heidelberg.