Which knee replacement do you need? 

This is a decision you and your surgeon will make based on your X-ray or MRI. But, it is good to be educated on the advantages and disadvantages of…

Partial knee replacement

Total knee replacement  

Bilateral knee replacement

Partial knee replacement: 

Based on your X-ray or MRI, if you have wear & tear on one side of the knee compared to the other you might be a candidate for a partial knee replacement.

Advantages:

Surgery time is shorter, which means less blood loss, which equals less risk/complications. There is also less tissue damage because only one side of the knee needs to be fixed. The ligaments of the knee are not cut or removed. This causes a faster post-op rehabilitation process compared to a total knee replacement. Most people can get back to what they want to do quicker and return to sports with less mobility issues, including range of motion, balance and strength. (1) 

Disadvantages:

There is a slight decrease in the amount of time a partial knee replacement lasts compared to a total. Some people will also eventually get wear and tear on the side of the knee that was not replaced causing the need to go under the knife again. 

Total knee replacement: 

If your X-ray shows wear and tear on both sides (medial and lateral) of the knee, your surgeon will recommend a full knee replacement. 

Advantages:

This type of replacement lasts longer than a partial knee replacement. The replacement lasts 10-20 years, depending on how active you are. You also will not have to go under the knife 2x because both sides we’re replaced. 

Disadvantages: 

Rehab is generally more painful and difficult compared to a partial replacement. More tissue has been cut, more bone has been removed. Your rehab will take up to 1 year, compared to 3-6 months post partial knee replacement. 

Bilateral knee replacement:

A lot of people have 2 bad knees so they are interested in getting both knees done at once to get it over with and to decrease need of using anesthesia twice. 

Advantages:

Someone with high risk of complications under anesthesia might chose this option with their surgeon. Some people get a single total knee replacement done and pledge to themselves not to ever do it again because of the difficulty of the rehab. Getting both done at the same time eliminates risk of backing out of getting that second knee replaced. 

Disadvantages:

The biggest disadvantage is definitely pain and mobility. It is very important to get up and walk after a knee replacement to decrease risk of blood clots and improve the mobility of your knee. With both knees replaced, walking will be difficult and painful. Having to do your exercises and stretches on both knee is time consuming and overall exhausting. A person who gets both knees replaced at once MUST be a very motivated, driven person. 

Citations: 

1. Harshvardhan Chawla, Jelle P. van der List, Alexander B. Christ, Maximiliano R. Sobrero, Hendrik A. Zuiderbaan, Andrew D. Pearle,
Annual revision rates of partial versus total knee arthroplasty: A comparative meta-analysis, The Knee,Volume 24, Issue 2, 2017,
Pages 179-190,