Seth S. Leopold, Md

SETH S. LEOPOLD, MD

SURGICAL ARTHRITIS CLINIC

SHOULD I GET BOTH MY KNEES REPLACED AT THE SAME TIME, OR SHOULD I DO THEM ONE AT A TIME, SEPARATED BY A FEW MONTHS?

This is an excellent question, and like many good questions, the answer is somewhat complicated. It is almost always technically possible to replace both knees at once -- but one has to ask: what would be gained or given up by doing this? As of now, there have been a handful of scientific studies that have asked that very question. One of those studies concluded that it is no problem to go ahead and replace both knees at the same time, but most of them came up with a slightly different response: the overall time to full recovery is shortened by doing knees at the same time, but you take some increased risk to gain this advantage. Here's the summary, as I interpret it:

The benefit of same-day both-knee surgery: The time to full recovery is shorter. If that does not seem intuitive, think about it this way: If you figure it will take between 2-3 months to really start to feel right after a knee replacement, and you do that twice, that's 4-6 months of total recovery time. If you do them both the same day, you go through the experience once, and the whole thing is behind you in 2-3 months.

The disadvantage of same-day both-knee surgery: The surgical risk appears to be increased. The types of complications that were more common in patients having the knees done together included temporary disorientation after surgery, the need for blood transfusions, and severe cardiac complications (which can be fatal). If the complication rates were doubled in same-day both-knee surgery, we'd call that a tie -- since you'd have to have the operation twice if you did it on separate surgical dates -- but in fact, the complication rates for all the complications I listed are more than double. The absolute magnitude of the risk of heart attack is still not huge, but the difference was noticeable; the risk of needing a blood transfusion went up considerably, though. To give you an idea, I very rarely need to give patients blood after a single knee surgery, but it is not at all uncommon if we do both at once. Finally, the overall length of hospital stay may be a bit longer with same-day both-knee surgery.

So, in view of this, why would anyone want to do them both at once? My observation is there are two sets of feelings on the part of patients about this. Some people are risk-averse, and want to minimize the risk as completely as possible; clearly, they would want to do one knee at a time. Other people are what I call therapy-averse (or pain-averse) -- they want to minimize the overall length of time they are either in physical therapy (perhaps for work reasons) and the overall length of time they are uncomfortable from the surgery. Provided they don't mind the increase in risk, these are good candidates for same-day both-knee surgery.

Finally, there are some people whose medical conditions (like a history of prior heart attacks) or very advanced age would make it simply a bad idea to do both at once.

In my experience, after having this conversation with patients who have severe arthritis in both knees, about half my eligible patients choose same-day both-knee surgery, and half choose to do them one at a time. So it's obviously a very personal choice, but one that is best made with all the facts at hand, and in consultation with a surgeon whom you trust.

I hope this helps you in making your decision.