In many ways, a total knee replacement is similar to a set of automobile tires. How long a set of tires lasts depends on how much the car is driven, on what types of roads the car is driven, how heavy the car is, and whether or not the car is properly serviced and maintained. Similarly, how long a total knee lasts depends on how much it is used, what types of activities it is used for, how heavy the patient is, whether the patient has regular check-ups with the doctor and whether the patient is staying in good physical condition.
No two patients are exactly the same and there is tremendous variability in patient activity. A set of automobile tires can last for many years if the car is not driven very much. Alternatively, a set of automobile tires can wear out in less than one year if they are driven many miles over rough roads. In many patients, their total knee replacement will last their lifetime. In others, it may last less than a year. Total knee replacements are designed to provide painless and unlimited standing, sitting, walking, and other activities of normal daily living. They do very well for golf, bicycling and swimming. They are not designed for jogging, or sports like tennis and skiing – although there are patients with total knee replacements that do these things! Total knee replacement surgery is done to improve quality of life. Each patient must decide for themselves what makes life worth living for them, and then pursue happiness through those activities. You should be aware, however, that the longevity of a total knee replacement may be shortened by frequent, vigorous activities.
In the event that a total knee fails, it is possible to implant another knee replacement. Such revision total knee replacement surgery may be a lesser or greater operation than the original total knee surgery. Similarly, recovery from revision total knee surgery may be easier or more difficult than it was from the original total knee surgery. In general, the results of revision total knee surgery are not quite as good or predictable as for primary total knee replacements. The results of revision total knee replacement depend on what the problem was that necessitated surgery. Following revision total knee replacement, most patients have good relief of pain and are able to walk as far as they desire.