All the staff in specialty centers are trained to do one task. All the equipment is for one procedure. This makes good economic sense for the doctors and owners of the specialized clinics and hospitals.

New specialty clinics are now focusing on hip and knee replacements. The same ideas apply. Communication among specialty staff is supposed to be better. The staff focuses on efficiency and organization. There may be less risk of hemorrhage, wound infection, and death reported in the specialized clinics.

But some experts think the specialty clinics do better because they have a healthier and wealthier group of patients. People from a higher income bracket are less likely to have diabetes and heart disease to compound problems after surgery.

Specialty hospitals are also less likely to use medical students, residents, or doctors-in-training to assist or perform the procedure. That means the patient benefits from the experience and expertise of a single surgeon doing many of the same operations.

According to a recent, very large study of Medicare patients, there is a 50 per cent lower risk of serious problems after joint replacement when done at a specialty orthopedic clinic.

This does not mean you can't or won't have an equally good outcome at a general hospital. The reasons for this difference between specialty hospitals and general hospitals isn't clear yet. More study is needed before final decisions can be made about where, when, and how to have a total hip or knee replacement.