Moderator Lachiewicz: So, Ken, let me ask you this. How precise do the bone cuts have to be with cementless total knees? Do you think this is for every man, every surgeon, or are we going to need robotics to do this correctly? What do you think?
Dr. Gustke: I think it’s important. If you’re doing cementless total knees, there’s definitely a difference in your surgical technique so that your surfaces are perfect, and your press fit is perfect. No different than what we have when we prepare an acetabulum for a press-fit acetabular component or the femoral stem for a total hip.
Moderator Lachiewicz: Okay, great. Tom, let me ask you. Do you think there are any patients that nowadays you would select a cementless total knee? What do you think should be the patient selection criteria?
Dr. Thornhill: The first problem for me, Paul, is I resurface every patella. And I don’t have a good metal-backed patella.
Moderator Lachiewicz: Ken, can you take on the question of do you think cementless knees have more pain or more dissatisfaction than a cemented knee?
Dr. Gustke: Having done this now for 30 years, I think there is a little difference. There’s more discomfort in the cementless knee. I can perhaps attribute that to the fact that there is more migration of the tibial component in the first 3 months or so. That may be the reason for pain. There’s more potential for blood loss because you’re not sealing the interfaces. I don’t think that has presented itself as a problem for the long-term, nor as an issue that has made me not choose to do uncemented knees. I think there is a difference, but it’s minimal.
Moderator Lachiewicz: Tom, do you think there’s a difference in quality in terms of pain relief, satisfaction, ambulation between those two fixation methods?
Dr. Thornhill: There has been reported in the OPCA series more blood loss in cementless. But now we’re much better at the blood loss. And if you account for patient selection, there’s probably no difference.
Moderator Lachiewicz: Ken, one last question for you. Do you think we’re going to have a reliable cementless patella in the future? Do we have one now? Do you leave those un-resurfaced when you do a cementless knee?
Dr. Gustke: My experience with metal-backed patellae was terrible. But never for the interface and never because they didn’t gain biological attachment. It was because of polyethylene wear. We have different polyethylene today than we had in the past, but it’s still thin. The real question is whether today’s polyethylene will be able to tolerate the stresses if it’s still only 3mm or 4mm in thickness. I don’t have an answer for that. I’m still doing cemented patellae in the majority of the cementless knees that I do.
Moderator Lachiewicz: Okay. Thank you to both of our speakers.
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As a physical therapist specializing in the rehab of patients who undergo total joint replacement, that was a great debate to read. I’m curious if we should or need to change our approach to rehab in terms of loading fully, gradually, or more delayed spending upon the use of cement or in the cementless cases. Now I’ll be able to ask my question intelligently when I see the surgeons up on the floors after their cases. Thanks for publishing.