Published on January 22, 2019

Am I ready for knee replacement surgery?Ready for knee replacement surgery?

Knee replacement surgery is big business. According to the American Academy of Orthopedics, more than 600,000 knee replacement procedures are performed in the US each year- a number that is expected to grow beyond three million by 2030. Osteoarthritis (OA) is at the heart of this growing problem. With an estimated 30 million Americans living with osteoarthritis today, it is little wonder why.

We recently sat down with Cape Cod Hospital orthopedic surgeon John Willis, MD, to discuss osteoarthritis and how to manage the risk for developing the disease - and keeping your knees as healthy as possible for as long as possible.

CCHN: Since osteoarthritis is the main culprit behind degenerative joint disease leading to knee replacement, can you describe what it is and who it affects?

JW: Osteoarthritis is the most common form of arthritis and occurs most frequently in the hands, hips and knees. With OA, the cartilage breaks down, exposing the bone to greater force. This causes pain, stiffness and swelling that worsens over time.

OA runs in families, so there’s a genetic risk for developing it. Certainly, those who have experienced injuries when they were younger, especially if they weren’t treated or treated properly, are at risk later in life as well.

My patients with degenerative joint disease due to OA are most typically in their 60s and 70s. And they’ve been suffering for a while.

CCHN: What are the risk factors for developing OA and are there things that can be done to prevent joint damage?

JW: Perhaps the biggest risk factor to developing OA is being overweight. When you are overweight you put more strain on your knees and that is directly correlated with developing arthritis. Most people take between 2-3 millions steps per year.  So, when you look at it that way, it’s pure math. It’s about 50 million more pounds of pressure you put on your knees, so they just wear out quicker.  If you lose weight, you stop adding the additional mileage to your knees.

Women are more likely than men, in general, to develop knee OA from being overweight, so gender is a risk factor.

People with a history of knee injury, and most especially those who overuse their knees doing repetitive activities, are also at greater risk.

As far as prevention goes, in addition to maintaining a healthy weight, it is important to stretch regularly, especially of you have tight hamstrings and quadricep muscles.

Add non-impact exercises like swimming to your routine.  And try to cross train regularly with different exercises to avoid over using and over loading the knees.

CCHN: Once joint damage has occurred, are there any treatment options that can move out the timeline for surgery?

JW:  We do have a few treatment options that can be done in the office to help. Some of the newer options include platelet rich plasma (PRP) therapy and hyaluronic acid injections.

They are primarily geared toward relieving inflammation and pain. Anti-inflammatory medications like Advil and Motrin, and cortisone shots are also helpful.

I think that when you get yourself to the point where you already have a little arthritis or a little thinning of the cartilage, it behooves you to try all of those, to try to squeeze a few more miles out of the knee. These are usually stop-gap measures, unfortunately. In general, these cases tend to eventually end up with either a partial or full knee replacement.

CCHN: It isn’t commonly understood that knee replacement surgery can be either a full or partial removal of the joint. Can you explain the differences between the two?

JW:  A full replacement, or total knee arthroplasty, replaces the entire knee joint, including all of the bone and cartilage surfaces. A partial knee arthroplasty only replaces a single compartment of damage. The knee has three compartments, including the area behind the kneecap. So, any of them can be replaced individually.

More and more partial replacements are being torn each year.

Many people have all of their arthritis in only one of those compartments. I like to at least identify that at least 95 percent of the patient’s issue is coming from one single compartment. We look at MRI images and X-rays to make that determination. If I think I can fix 95 percent of your problem by replacing it with a partial procedure, then you are probably a good candidate for it. And it can be a better procedure because you are leaving two-thirds of their knee alone.

CCHN: At what point do you know it is time for a replacement?

JW: When you have exhausted all of the reasonable treatments. And there are a lot of unreasonable treatments out there. I can tell you stories of patients who have travelled to Florida and spent $8,000 in cash for some magical injection in their knee, only for me to have to replace it three months later when it didn’t work.

But, the tell-tale sign is when the pain in your knee is your focus every day. Then it’s time to do it. If it’s occasional, you are probably not there yet.

For a partial, I tell people when you can’t exercise to keep yourself healthy or you can’t do the things that you want to do for either your mental or physical health, then you should have a partial.

Total knee patients are a different population. Typically, they are a little bit older, have lived with arthritis a little bit longer, and may be they were less active to begin with. They have become less active because their knees are bothering them and they have multiple joints involved. And for that person, when the day-to-day life revolves around the pain in their knee, it’s time to get this fixed.