Moderator Lieberman: Tom, we’re going to start with you. What would make you consider doing some cementless knees?
Dr. Schmalzried: I’ve got nothing against cementless. If I’ve got something in my hands at this stage of my career that works well, I’m hesitant to change.
Moderator Lieberman: Matt, what are the indications for a cementless knee?
Dr. Abdel: There are several but to narrow the scope, patients who need additional fixation due to bone quality, age (very elderly), increase in constraint are not the cases. My typical patient would be a 55-year-old gentleman, very active, good bone. In my practice I’m about 25% cementless; 75% cemented. So, I think we’re still kind of defining the indications and roles for the patients.
Dr. Schmalzried: I’m going to say what Matt said but in a different way. If you’re going to do something different, you do it in patients most likely to need it. I think young, active male would be a good place for me to start if I was going to try cementless.
Moderator Lieberman: What about PS knees, Matt, with a cementless design. People worry that too much constraint will affect fixation on the tibia.
Dr. Abdel: Good question Jay. I do think 3D printing has helped us get better designs—particularly in the tibia. That will be the kind of keel-peg mechanism where you get rigid fixation even with the PS design. And really what we’re talking about here is 8, 9, 10 weeks of rigid fixation to get that long-term biologic ingrowth. 3D printing has allowed us to get rigid fixation to promote long-term biologic ingrowth.
Moderator Lieberman: Matt, let’s say you’re doing a cementless total knee and you’re a little off on the chamfer cuts and look at the tibia and there is a little space there. How tight does it have to be and what’s the bailout? In the system you use do you just switch to a different tibia or different femur and then cement it in place?
Dr. Abdel: Your cuts have to be pristine. Your preparation has to be accurate. I don’t tolerate much deviation from pristine cuts on that. Now if you do need to bailout…say the bone quality is poor or you don’t like your cuts…my bailout is the same system with the cemented version. Just like cemented fixation, there’s a finite technique when doing a cementless fixation and pristine bone cuts are important.
Moderator Lieberman: You guys did a spectacular job. Gentlemen, terrific. Let’s give them a round of applause.
Please visit www.CCJR.com to register for the 2019 CCJR Winter Meeting, – December 11 – 14 in Orlando.
I am a patient of Dr. Schmaltzreid, who performed a double total knee replacement surgery on me nearly 20 years ago. For the past 20 years I have not experienced even the slightest discomfort, pain nor movement impediment. I am absolutely amazed by the astounding success and best possible results that he was able to achieve!! I am absolutely convinced that the artificial knees that he installed, but most importantly his thorough knowledge, incredible skills and understanding not to mention his vast experience in performing this type of surgery were the determining factors responsible for the amazingly successful results that he was able to achieve on my total knee replacement surgery. I am immensely grateful to Dr. Schmaltzreid for having given me 20 years and counting of pain-free and worry-free life! He is definitively the greatest hero of my life!