Simultaneous bilateral total knee replacement and staged bilateral replacement produce equally good relief of knee pain and equally good return of knee function. The decision is based on the health status of the patient. The ideal candidate is in good physical health, with no cardiac, pulmonary, or vascular disease. When both knee replacements are done at the same time, you have only one surgical "event" with a single anesthesia. Hospital stays have been found to be shorter and rehabilitation faster in patients who have both knees replaced at the same time.