Mako Robotic Arm Assisted Surgery for Joint Replacement

Dr. Christopher Hamilton shares information about the use of the Mako robotic arm in joint replacement surgery.
Mako Robotic Arm Assisted Surgery for Joint Replacement
Featured Speaker:
Christopher Hamilton, MD
Christopher D. Hamilton, MD Specializes in Arthroscopic and Reconstructive Surgery of the Shoulder, Knee, Elbow, Sports Medicine, and Joint Replacement of the Shoulder and Knee Fellowship-Trained Sports Medicine and Shoulder Surgeon. Christopher Hamilton, MD, graduated with distinction from Stanford University in 1984 with a bachelor's degree in chemistry and biology. He earned his medical degree from the University of California, Los Angeles, in 1988, completing his internship and orthopedic surgery residency at Yale-New Haven Hospital in New Haven, Connecticut, in 1993. Dr. Hamilton then spent one year at the Kerlan-Jobe Orthopedic Clinic in Inglewood, California, where he completed a fellowship in sports medicine and shoulder surgery. During his fellowship, he was an associate team physician for the Los Angeles Dodgers, Los Angeles Kings, Anaheim Mighty Ducks, Los Angeles Lakers, and Loyola Marymount University. Dr. Hamilton was a clinical instructor of orthopedic surgery at Yale University from 1992 to 1993, and from 1994-1997, he was an assistant professor of orthopedic surgery at the University of Texas Medical Branch in Galveston, Texas. He was directly involved in the training of medical students and orthopedic residents and fellows. He joined Southern California Orthopedic Institute in 1998. Board-certified by the American Board of Orthopedic Surgery, Dr. Hamilton is an associate member of the Arthroscopy Association of North America and has written numerous research articles focusing on shoulder, elbow, knee, and sports medicine topics, presenting papers both nationally and internationally. His research interests include dynamic stability of the shoulder and elbow, shoulder fractures, and joint replacement, and athletic injuries of the knee, shoulder, and elbow. He and his wife Susan have three children and live in Bakersfield. In his free time, Dr. Hamilton enjoys his family, cooking, wine, traveling, recreational golf, and skiing. Christopher D. Hamilton, MD, is available to see patients in the Bakersfield office
Mako Robotic Arm Assisted Surgery for Joint Replacement

Bill Klaproth (Host):  There has been amazing advances within robotic surgery especially when it comes to orthopedic surgery. One of them being the Mako Robotic Arm to assist with surgery of joint replacement such as when you have your knee replaced. So, let’s learn more with Dr. Christopher Hamilton, an Orthopedic Surgeon with the Southern California Orthopedic Institute in conjunction with Dignity Health. Dr. Hamilton, thanks so much for your time, it’s great to talk with you. So, as a basis for our discussion today, let’s focus on knee replacement. So first off, let me ask you, how successful is total knee replacement in general?

Christopher Hamilton, MD (Guest):  So, in general, joint replacement is one of the major life improving operations that we have in modern medicine. Replacement of a knee or a hip can be life changing for patients. It can allow them to get back to the level of function to have a pain-free life, to enjoy their family, to exercise, to return to some athletics and in general, it has been extremely successful for more than 90% of the patients who undergo joint replacement.

Host:  And then with the evolution of total knee replacement comes the advances in techniques and equipment such as the Mako Robotic Arm to assist with surgery. So, can you talk about that advancement and the Mako Robotic Arm?

Dr. Hamilton:  Absolutely. So, as we have started to do knee replacements, we’ve started with a very successful operation using conventional instruments that rely on patient’s anatomy. Over time that’s evolved to where as in most of medicine, we’ve started to use increasing imaging techniques whether it’s CT or MRI to help us actually figure out each patient’s specific anatomy a little bit better. As we have included that, we’ve done what are called guided resections where you cut a specific amount of bone but that doesn’t always take it into account some of the soft tissues. What the robotic assisted arm has allowed us to do, using the Mako, has now taken this to the next step, so that we can define a patient’s specific anatomy and more importantly, define what cuts would be best to do the best total knee when we are cutting bone and more importantly, to put it in the right position with the right balance for each specific patient. So, it allows a degree of customization and precision that we have not had up until this time.

Host:  And then so we have a basic understanding, what are the overall advantages of this?

Dr. Hamilton:  Some of the major advantages are that we are more accurate with our surgical plans. We may have less ligament damage and associated damage as we are trying to do an invasive operation. After six months, many patients have lower pain scores than those who have undergone conventional replacements and by and large, we have had equal or higher satisfaction scores in patients who’ve undergone standard replacements. So, those are all great benefits for the patient in relatively short term technology and timing.

Host:  Right, so then the overall goal of the Mako and maybe you can explain these terms to us is to get rid of any outliers and head closer to a forgotten knee. Can you explain that to us?

Dr. Hamilton:  Yes. Let’s start with the second one first which is a forgotten knee or forgotten joint replacement. In general, what we would like to have a patient do in six to twelve months after having a replacement is to not remember that they had their joint replaced. In other words, we would like to get a patient back as close to normal as they were before they had their onset of arthritis or progression of arthritis. Now it’s not realistic to think that we’re going to make a patient 18 years old again but if we can get a patient back to their quality of life without thinking about their knee or making lifestyle concessions for their knee after replacement; that’s what we consider to be a forgotten knee.

Now when you talk about outliers, what we mean is that in general, probably 80 to 90% of knee replacements are fairly straightforward. In other words, patient’s anatomy is straightforward, the soft tissues are straightforward and using conventional instruments, we will get a very successful and satisfactory result. But you don’t always know when you start a patient and start a surgery which patient may have other issues that you don’t expect to see. And as a result, when we look at our postoperative evaluations; there are some that don’t hit right in the sweet spot even with our best intentions with very good surgeons. In other words, our alignment may be off by a degree or two or three. We may change where the knee cap is sitting or where the femur is sitting in conjunction with the patient’s alignment. Our goal and the Mako certainly does this, helps to get rid of those patients that aren’t right in the sweet spot in the middle and as we move more people to the sweet spot; the patients that are “outliers” get better results.

Host:  Got it. That makes total sense. So, in essence then, the Mako allows for better customization and then it also increases precision and alignment and position during surgery. Is that correct?

Dr. Hamilton:  Correct. It improves both precision and accuracy. So, when you look at technical terms, it both makes you precise, meaning your cuts are within a millimeter of where you plan them, and they are more accurate because you’ve taken into account both the patient’s bony alignment and their soft tissues which most other techniques do not allow you to do.

Host:  And this will then ultimately, hopefully increase the percentage of people having a forgotten knee as you say.

Dr. Hamilton:  That is certainly the goal and thus far, the preliminary and early results are excellent in terms of looking at improving patient outcomes.

Host:  So, this is a clear case where technology has definitely helped the patient, but it also sounds like it has helped you as a surgeon as well?

Dr. Hamilton:  One of the very interesting things I think is that the Mako seems to make good surgeons even better surgeons. And sometimes, you don’t know what you don’t know until you find something that improves what you were doing before. And I think for me, and my partners who use the Mako; what we’re finding is that this is making us even better when most of our patients have been doing very well.

Host:  So, it seems like the Mako would be a benefit to anyone, however, are there some candidates who are better suited for the Mako?

Dr. Hamilton:  There are some patients that are extremely good candidates, in other words, I would not choose to do your knee without the Mako. And those include partial knee replacements, difficult or complex deformities, and other patients where we would have had trouble doing a conventional knee replacement. This allow us to do a better job in those patients. But almost every patient is a reasonable candidate for the Mako because it will help you to not be one of the 10 or 15% that we didn’t expect to have an issue with.

Host:  And I think that’s an important consideration as well. And now that people have a better understanding of the Mako, at what Dignity institutions in Bakersfield is this available?

Dr. Hamilton:  So, currently one at Bakersfield Memorial Hospital and one at Mercy Hospital at their Truxtun location.

Host:  Very good and if you could wrap this up for us and thank you so much for your time. Is there anything we missed, is there anything else you want to say about Mako Robotic Arm Assisted Surgery?

Dr. Hamilton:  Yes, I have one other thing because I think the conception also is that the robot is doing the surgery. The robot is not doing the surgery. The robot is helping your surgeon make precise and accurate cuts and allowing positioning of the implants in the best position to give a successful outcome after a joint replacement. So, it’s a tool that allows your surgeon to do a better job. The robot is actually not doing the surgery. We are there guiding the robot but it’s helping us to do a better operation.

Host:  So, it’s high tech, high performance tool in the tool belt if you will.

Dr. Hamilton:  That’s exactly right.

Host:  That’s wonderful. Well this has really been interesting and very educational. Dr. Hamilton, thank you for spending time with us and talking to us about the Mako Robotic Arm Assisted Surgery.

Dr. Hamilton:  Thank you. It’s my pleasure.

Host:  that’s Dr. Christopher Hamilton and for more information please visit, that’s And if you liked what you’ve heard, please share it on your social channels and be sure to check out the full podcast library for topics of interest to you. This is Hello Healthy, a Dignity Health podcast. I’m Bill Klaproth. Thanks for listening.