Selected Podcast

ConforMIS Customized Knee Implants

When other treatment options have not relieved your knee pain, your surgeon may recommend a knee replacement. A knee replacement involves removing the damaged part of the joint and replacing it with an artificial joint.

Stoughton Hospital offers ConforMIS customized knee implants. ConforMIS is a knee replacement implant that is designed specifically for your knee, rather than a traditional, off-the shelf implant. This provides an individual fit designed to follow the shape and contour of your knee.

Listen in as John S. Rogerson, M.D., discusses how the orthopedic surgeons at Stoughton Hospitals are using the ConforMIS customized knee implants to help patients feel better about their knee replacement.
ConforMIS Customized Knee Implants
Featured Speaker:
John S. Rogerson, MD, S.C.
John S. Rogerson, M.D., graduated Phi Beta Kappa magna cum laude from Dartmouth College with a Bachelors of Science degree and as a Rufus Choate Scholar. He received his medical degree from the University of Iowa Medical School and was a member of the Alpha Omega Alpha medical honor society. His internship was completed at McKennan Hospital in South Dakota and his orthopaedic residency the University of Wisconsin Hospitals. Dr. Rogerson is board certified by the American Board of Orthopaedic Surgery and has served as a clinical assistant professor at the University of Wisconsin – School of Medicine.

Learn more about John S. Rogerson, M.D
Transcription:

Melanie Cole (Host): If knee pain is limiting your daily activity and other non-surgical treatment options have not provided pain relief, your surgeon may recommend a knee replacement. My guest today is Dr. John Rogerson. He's an orthopedic surgeon with Stoughton Hospital. Welcome to the show, Dr. Rogerson. So, what are some of the most common causes of knee pain that you see every day?

Dr. John Rogerson (Guest): Well, the most common ones are probably meniscal tears and just inflammation of the knee. The meniscal tear, we can handle those with arthroscopy. The inflammation responds fairly well to injections and anti-inflammatories. But, as the knee wears out and the articular cartilage, the white coating on the ends of the bone, wears down, you get bone articulating with bone and that becomes very painful and that's where people then evolve into needing a total knee replacement.

Melanie: So, when you've discovered that somebody is going to possibly need a knee replacement, what risk factors would precipitate this or what factors go into deciding that they need a total replacement?

Dr. Rogerson: Two things, really. I mean, the most important is the pain and the loss of lifestyle that they're having at that point. X-rays, obviously, are important because that will really tell you how severe the arthritis is and the deformity, but it all comes down to if the pain is interfering with their enjoyment of life significantly.

Melanie: So then, let's talk about knee replacements. People have heard that they can't go through airport security with these devices. Tell us what's going on in the world of knee replacement right now.

Dr. Rogerson: Well, there's been a recent breakthrough technology in the evolution of total knee replacement and the Conformis total knee, which we will be discussing, I think, is a significant advance to where we were before. You know, the knee replacements are metal and plastic, and so, no matter what type of knee replacement you have, you will set off a machine in the airport, but that is a real minor inconvenience to the marked improvement in lifestyle that you can get in terms of pain relief with the knee replacement.

Melanie: So, tell us about Conformis. What makes that different?

Dr. Rogerson: Well, the Conformis, it utilizes a full lower extremity CT scan and patented software, and 3D printing technology to make an individually customized prosthesis for each patient. Prior to this, we basically, took kind of the average shape of prostheses for men and women and had small, medium, and large sizes and more variety, but, at the end of it all, and we had developed increased technology in terms of making precise cuts with the use of MRIs and CT scans, but, at the end of it all, we were just pulling it off-the-shelf total knee replacement and putting that into the patient. In at least 10-15 or 20% of patients, it just didn't quite fit and they were not perfectly satisfied. So, the big difference in this is that you are making a one-of-a-kind, individualized custom-made prosthesis off of that patient's anatomy. And so, not only does it make the prosthesis and fabricate it, it also makes the customized instruments to put it in.

Melanie: So, how does it do the individualized fit until you're inside the knee and you see what's going on in there?

Dr. Rogerson: Well, with the help of a CT scan, you actually take a long leg extremity CT scan which gives you the exact sizes but, more importantly, the exact shape of each individual patient. Then, that CT scan is corrected for angulation and rotation and then that, utilizing 3D printing technology, makes a mold, which is then fabricated into metal and plastic. So, it allows the surgeon now to make an exact replica of the patient's knee so that when you do make the incision, all the jigs, all the instruments, and the prosthesis itself are an exact match for that patient. You really don't have to futz around like we used to with kind of an off-the-shelf variety that we try to make it work as well as it could in the patient's knee which it may not have fit exactly.

Melanie: And are there advantages for bone preservation for their surrounding bones?

Dr. Rogerson: This one takes a little less bone off the femur and perhaps slightly less off the tibia, but that's not the major advance. More importantly, is the fact that each curve in this prosthesis exactly matches the patient's own anatomy and there are no gaps in the range of motion where it tends to get loose or too tight. It just matches the patient's previous anatomy. That's the major breakthrough. You can kind of conceptualize it as it would be similar to going to Walgreen's and getting a medium knee brace for ACL deficiency as opposed to getting a customized knee brace made from a cast of your leg. It's that big of a change in terms of knee replacement.

Melanie: And what is it like for the patient after the fact? What's the recovery like with the Conformis?

Dr. Rogerson: Well, in talking with other surgeons around the country that have made the switch to the Conformis, the recovery appears to be somewhat quicker and smoother but, more importantly, the patient satisfaction seems to be more universal and profound.

Melanie: And as far as how it feels and how long it lasts, is there any difference there?

Dr. Rogerson: Well, again, the guys I have talked to and relate to around the country report that the patient feels like it's more their own, just like their own knee, and doesn't feel artificial down the road. I mean, people get back to reasonable activity even with off-the-shelf total knees and, you know, I'd say about 80% of people with traditional off-the-shelf total knee replacement are pretty happy with their prosthesis, but they will tell you that it doesn't feel like a normal knee. We're hoping that this solves that 20% of patients that are not just enthralled with their knee at all; they've just struggled with it.

Melanie: Is there a difference in price, Dr. Rogerson, because it's customized?

Dr. Rogerson: Yes, it is more expensive but, happily, I'm working with Stoughton Hospital who feels that personalized care is important for the patient and we are going to offer it in the Madison and Southern Wisconsin area. They are dealing with the insurance companies and Medicare, so I'm very pleased that they are willing to offer this advance, even though it costs a little bit more than the off-the-shelf variety.

Melanie: And how long until someone can resume activity after they get a full knee replacement?

Dr. Rogerson: Well, the post-op rehab and follow-up is critical to any total knee, whether it's the Conformis or an off-the-shelf total knee, so it's always variable. There's a bell-shaped curve in terms of how people recover but we believe that this bell-shaped curve is going to be much narrower and quicker than the traditional off-the-shelf variety. But, when the patient wakes up from the surgery in the recovery room, they are on a CPM machine that continually moves the knee, they get up walking that afternoon on crutches, they can weight-bear tolerate it. Usually people are working their way off the crutches in several weeks. Then, we get them on an elliptical machine very quickly and a stationary bicycle. I mean, there have been reports, and you can look on the internet and see videos of people out golfing after three weeks. Those are, obviously, the people that are doing the best and that's why they get put on videos for advertising purposes.

Melanie: So, in just the last few minutes, and how fascinating this is, Dr. Rogerson, give your best advice for people suffering from knee pain that are considering knee replacement surgery.

Dr. Rogerson: Well, first of all, I would tell every patient to do all of the conservative non-operative modalities that are available. Those include oral anti-inflammatories, a cortisone shot sometimes will be helpful. We do those very rarely. Hyaluronic acid injections can really give people some relief for several years even though they've got a bad looking x-ray. So, we try everything that we can from a non-operative standpoint to keep people functional but, eventually, when the pain gets to the point where it's a daily occurrence and particularly when it interferes with people's sleep patterns and their ability to earn a living or just to enjoy activities of daily living, that's the time when you would consider total knee replacement. I think that there now is a considerable advance in the technology and the fabrication of total knee replacement. I'm really excited with the help of Stoughton Hospital, I'm going to be able to offer it to patients in the Madison area.

Melanie: Thank you so much. It's just such great information-so fascinating. Thank you, Dr. Rogerson, for being with us today. You're listening to Stoughton Hospital Health Talk and for more information, you can go to stoughtonhospital.com. That's stoughtonhospital.com. This is Melanie Cole, thanks so much for listening.