[Can we respond to the rising expectations on arthroplasties?].

There has long been an increasing interest in knowing the future of arthroplasties, mainly of the hip and knee, as a basic element in the provision of healthcare services. This is true in both European countries with a public and universal National Health System (NHS) and in others, whose paradigm is the U.S.A., with much lower public spending and health policies based on private services. This interest arises, firstly, from the growing demand for high-quality results in each arthroplasty which are also adjusted to individual patient requirements, including leisure activities and religious practices requiring considerable joint mobility, such as in certain oriental cults. Secondly, this service is progressively provided for more patients and is also increasingly expensive, much more so considering that the cost will be even greater in the future due to a notable increase in review surgery. Many journals of our speciality have been dealing for years with technical advances and also with issues related to cost-effectiveness. Paradoxically, there is a significant difference between the consideration of a good result by orthopaedic surgeons and by patients, as this perceived quality concept is affected by geographic, ethnic and social variables. Individual expectations extend to the clinical result and also to factors such as accessibility, waiting time, catering quality and follow-up, giving a general feeling that individual expectations have become unlimited. Alongside these factors there are also others which could be described as social expectations, such as accessibility to arthroplasties being part of an advanced and supportive society; a concept known as equity. However, the sustainability of national healthcare services is seriously hampered by the increasing ratio of occupationally inactive versus active individuals. This progressive and apparently unsustainable demand on national healthcare services will hardly be compensated by private funding, paradoxically much more inefficient for the national gross domestic product. Thus, in the