Understanding the Difference Between Partial and Total Knee Replacement

Knee replacement sounds like a single decision until you learn the knee has three compartments and arthritis doesn’t always hit them equally. We break down partial vs total knee replacement in a way that maps directly to what patients see on X rays and feel in daily life, so you can walk into an orthopedic visit with clearer expectations and better questions.

We talk through the real anatomical difference: total knee replacement is usually the right choice when arthritis affects two or more compartments, while partial knee replacement can work when wear is truly isolated. We also explain the two common partial options, including unicompartmental replacement for the inside or outside of the knee and patellofemoral replacement for arthritis behind the kneecap. Along the way, we dig into why surgeons aim to preserve healthy joint structure when possible, especially for younger, active patients thinking about the long view.

Recovery is the next big question, so we unpack what can change after a partial procedure, including the potential for less swelling and stiffness and a quicker return of range of motion. Even with those differences, the core message stays the same: movement is key, and consistent rehab supports pain control, mobility, and strength. We also share how prehab works, why it often starts about a month before surgery, and how to keep the exercise plan realistic if pain has limited your activity.

If you’re researching knee replacement surgery, knee arthritis treatment, or physical therapy after knee replacement, this conversation will help you understand the tradeoffs, the timelines, and the decision points that matter most. Subscribe, share this with someone considering surgery, and leave a review with the question you want us to tackle next.

To learn more about The Bone and Joint Center at Magee-Womens Hospital visit:  https://www.pghbjc.com
Dr. Noelle DiGioia Guthrie
300 Halket St. 
Pittsburgh, PA, 15213 
412-683-7272  

To learn more about The Wellness Center for Bone and Joint Health visit:  https://www.boneandjointhealth.org
Tiffany Belculfine
300 Halket St., Suite 1601 
Pittsburgh, PA, 15213 
412-641-8594  

Transcript

Welcome To The Joint Effort

SPEAKER_00 0:04

Welcome to the Joint Effort Podcast, where mobility meets reality and your future self says thank you. Your host, Dr. Noel DeJoy Guthrie of the Ponent Joint Center of the G Women's Hospital, and Tiffany Elkafine, physician assistant at the Wellness Center of the Ponent Joint House, serving adults across Western Baseball. If you're the sound like Bob, you're just arguing putting on stop with your side eye stairs. You're in the right place. Every day, they'll break it down and build you back up with a personalized plan for real life. Now, let's get you moving. Here are Dr. Noelle and Tiffany.

Partial Vs Total Basics

SPEAKER_03 0:55

Knee replacement is not one size fits all, and understanding the difference between partial and total procedures can help patients feel more confident and prepared. Welcome, I'm Julie Schwenzer, co-host and producer with Dr. Noelle DeJoya Guthrie of the Bone and Joint Center at McGee Women's Hospital, and Tiffany Belkafine, Physician Assistant at the Wellness Center for Bone and Joint Health. Hi, ladies, it's great to be back with you.

SPEAKER_01 1:21

Hi, Julie. Hello, thanks for having us again.

SPEAKER_03 1:23

Yeah, we're so happy that you're here. You guys are so good at clearly explaining things. So if you could break it down so patients understand when each option makes sense and what they can expect. Dr. Noel, what's the difference between a partial and total knee replacement?

Recovery And Rehab Differences

SPEAKER_01 1:39

Sure. Very good question, which I think, you know, can get confusing to patients, but to um go back to basics, we kind of have to go back to our anatomy, particularly of the knee joint. So, and we're talking exclusively um knee right now. So the knee uh is made up of three compartments. So you we call it the medial compartment of your knee, the lateral compartment, and then your patello femoral joint. So that's between your kneecap and your femur. Um, and you can get arthritis in all three compartments. You can get arthritis exclusively in the medial, the lateral, or the kneecap compartment. Um, it kind of depends on the patient. So when we get x-rays in the in the clinic, we always get x-rays that look at each compartment and we can evaluate each one. Um, there are definitely some patients who just have exclusive arthritis underneath the kneecap and their other joint spaces are well maintained. Um there's some patients who get it more in the outside or the inside of the knee, so the meteorolateral compartment. And that kind of dictates our surgical decision making. So in patients who have arthritis in two or more of those compartments, they're indicated for a total knee replacement, meaning that we basically kind of shave off the arthritis at the end of the femur, the top of the tibia, and the underside of the patella, usually. So that's called we're replacing all three compartments of the knee. Um, but then there are patients who exclusively have arthritis, which is bone on bone underneath the kneecap, or on the outside of the knee or the inside of the knee. Um, if you have just one compartment where arthritis is really bad, we can do a partial knee replacement. So two different types of partial knee replacements. You can do a patellophemoral joint replacement, which is just under the kneecap, um, or you can do a unicompartal knee replacement, which can be either on the inside or outside of the knee. Um so that's kind of going back to, you know, going back to anatomy and understanding that kind of dictates, you know, how we evaluate patients and indicated for surgery. There's a few other like specific indications if you were to um proceed with a unicompartmental knee replacement or a total knee comp replacement, but that's you know, discussion between individual patients and their physician. For patients, what are the biggest possible differences in recovery timelines based on if they did a partial or full So I do think historically, and you know, the the unicompartmental and the patelloframal joint replacements, so the the partial knee replacements tend to recap a little bit faster. Obviously, you can um imagine it's a little um less of an intense procedure because you're just replacing one part of the knee rather than the whole. So you're doing a little less instrumenting the bone, the approach is a little bit less invasive. Um, so it is tends to be a little bit quicker of a recovery. And and on the other side of things, a lot of the patients with those with the indicated for a partial knee replacement tend to be younger. Um, so you know, for that reason, it might be a little bit easier for them to rehab. So our rehab protocols, though, you know, when going to therapy and stuff are the same. There's, you know, no restrictions one way or another. Um, they can still do the same exercises, but the partial knee replacement category do tend to recover a little bit faster in general.

SPEAKER_03 4:46

After a partial um replacement, how do you see like the therapy going usually after that compared to somebody who had a full knee replacement? And that's interesting that you said, Dr. Noel, that it's usually like younger patients that might get the partial. So I'd imagine the therapy is a a little bit more maybe different for the younger ones.

SPEAKER_01 5:07

Yeah, I think I mean, you know, like we talked, the surgery is not, I don't want to say as invasive, but it's not as as much um like work with the bone and soft tissue releases. So it does tend to go a little bit quicker. You know, you can get less stiff, less swelling, your range of motion for that reason is a little bit better, quicker on in the process. Um, obviously, all patients are different, you know. We can't really generalize that, you know, across all across the board. But um, most of the time the partial knee replacements tend to, you know, progress a little bit quicker. Um, so do a little bit more things, you know, sooner in the timeline of post-op recovery. But like I said, we still we encourage all patients, whether you have a partial or a total knee replacement, movement is key, you know, doing exercises that helps with the swelling, it helps with your range of motion, it helps with your pain. Um, so there's really no restrictions, you know, if you've had a total or a partial knee replacement. Um, we kind of patients can go as fast as they want, as fast as fast as they can.

SPEAKER_02 6:05

And we do like to let them know that the better prepared they are ahead of time, the easier their recovery will be afterwards, too. So at least here in the Bone and Joint Center, I can't speak for other orthopedic practices, but I would assume it's a similar circumstance. People are given exercises to do beforehand so that they know how to keep their quad strong, how to keep that muscle well supported, how to get that joint a little more flexible, so that then when they need to go through with the procedure and then they're doing rehab afterwards too, that they already know, oh, these are the exercises I do and this is how I do them. And it kind of reminds the body of that muscle memory too.

Choosing Based On Goals

SPEAKER_03 6:41

And what should patients consider when deciding which procedure aligns best with their lifestyle goals and you know what they need to do in the long term?

SPEAKER_01 6:52

So I I do think that um it's more based on your arthritis and what how you present on x-rays and symptoms for sure. I think, you know, that's the biggest indication is if you have arthritis in one compartment versus two or more. Um, and then, you know, it's a discussion between your doctor and the patient as far as, you know, what you want to proceed with. I do think, you know, like I said, usually younger patients have the partial knee replacements because they have more isolated osteoarthritis. Um, and you know, it's it's important because we want to save as much joint as we can because, you know, patients who are having total knee replacements when they're in their 40s, the chance of them having to have a redo surgery, so we call revision surgery, are on the higher side because components can start to just wear out with time. You know, our our technology has gotten really good as far as, you know, making the components, but you know, they they do have a lifetime and a shelf life, so they might wear out with activity. So thinking of someone who has a tonal replacement when they're 40, you know, 40 years after that, you're 80. And, you know, with lifespan these days extending into the 90s and hundreds, the chances of you happening to have a redo are a little bit higher. So, you know, sometimes we'll talk to younger patients and it might be better to do a partial knee replacement, preserve some of their normal kinematics of their knee. Um, and on this the same side of things, a lot of times, and not everybody, but if you have a partial knee replacement, sometimes you do develop osteoarthritis in the other compartments as you grow older. So then sometimes we do, you know, have to revise that partial knee replacement to a total knee replacement. So definitely all good questions to talk, you know, specifically with your provider about, you know, how your x-rays look, um, you know, your physical demand. Um, but those all kind of more personal questions that you would talk with your provider about.

Prehab Timeline And Expectations

SPEAKER_03 8:45

And the last question I have, I guess for Tiffany, would be that the therapy, the pre the pre-op, what does that look like? And how long before the actual operation do you have to start like prepping and and starting to get to know what you know lies ahead?

SPEAKER_02 9:01

You know, certainly it always depends on the patient. Someone who is already in really good shape and really takes care of themselves probably won't need as long to rehab beforehand. Would you agree with that? Yeah. Um so then people who maybe don't get to move around as much because unfortunately they get stuck in a pain cycle, right? So they can't move, so they sit still. And then when they need to get up, then uh they're stiff and they're sore, and then they're more sore, so they sit down again and they're just they're not moving as much. So when they're not moving as much, you know, we give them a list of 10 or 15 exercises and it's overwhelming for them. Um, it can take them, you know, two hours to get through those exercises. But that's not what we want to happen. We want them to be able to get it efficiently in their day, but sometimes like they do two or three exercises and they're so sore that they can't continue. So it's it's really a patient-based focus, you know, to figure out like the best time to start the pre-op exercises. Those are given at least a month in advance. Yeah. Um, so people have plenty of time to get those in and and start to rehab that. And then again, continuing the same process with the new knee or the new partial knee afterwards.

How Common These Surgeries Are

SPEAKER_03 10:07

I guess my last question for both of you is how many knee replacements, partial handful, are you seeing like a month? Is it is it so high?

SPEAKER_01 10:17

So, so just um historically, partial knee replacements a lot less common. Um, so I'd say for every, you know, and this is uh, you know, I don't know the literature behind this, but maybe for every uh, you know, 10 to 15 total knee replacements, there's one partial knee replacement. So a lot less common. We don't do them as much just because they're not indicated as much. Um and as far as volume, I mean that kind of depends on the place. We're high volume, basically just do total joints here. Gosh, per month. Um I couldn't tell you. I have no idea. So so it's I mean, a high volume surgeon can do up to five to six hundred plus cases a year. So give you an idea. And that's just one surgeon, you know, with you know, who's pretty high volume. Um you know, per month if you divide that. It's it's a lot of cases. I mean, I think that's one thing that actually makes our program here great is that we have a very high repetition. We have our own ORs, everyone knows your plan. We have a very good, well-oiled machine from, you know, in the office when they're seeing them for pre-testing to day of surgery to post op. So I think the more you do of one thing, the better and more efficient you can get at it. And it helps patient outcomes for sure. Um, but it's definitely in general, you know, the partial knee replacements a lot less common than the total knee replacements.

SPEAKER_03 11:38

Okay, well, thank you both for breaking that down and um helping us understand all the options with knee replacement. So we appreciate you. And we'll see you next time on the Joint Effort Podcast.

Scheduling And Contact Info

SPEAKER_00 11:52

That's today's dose of strength, balance, and better movement from the Joint Effort Podcast. Ready for care that fits your life and gets you moving? To schedule an appointment with Dr. Noel for your surgical and injection needs, call 412-683-7272. Or visit PGHBJC.com. Or if you are looking for lifestyle changes that are not searchable, contact Tiffany Belgifine. Call 412-641-8594 or visit bone at jointhealth.org. Healthy bones and happy joints make every day better. Until next time, keep moving, stay steady, and take care of yourself.