Walter v. MacDonald: Ceramic-Ceramic: Articulations of Longevity for the Young Active Patient

What about the histology of ceramic-on-ceramic bearings?

It’s relatively benign. We do see mild synovitis in the synovium of the hips where we revise the ceramic-on-ceramic bearing. So, we’ll get mild synovitis and polymorphs, that’s different to polyethylene where you have the granuloma, or you have visible wear debris on the microscope, and more synovitis. It’s much different to metal-on-metal where you have the necrosis. So, we do see a yellowish grainy debris in the ceramic-on-ceramic retrieval in the tissue around the hips.

We have seen about two cases of osteolysis with ceramic. In those cases we saw black debris and the ceramic debris. When we looked at it under backscattered scanning electron microscope, we could see paradoxically a lot of titanium as well as the alumina ceramic.

So paradoxically the dominant wear debris in a ceramic bearing is titanium not the alumina. We’ve also looked at squeaking, but squeaking is generally infrequent, and it generally occurs with bending not walking.

We also use a lot of large diameter ceramic-on-ceramic bearings and for me that’s one of the big advantages.

So, in conclusion ceramic-on-ceramic has low wear, the wear debris is inert, the fracture risk is low and the squeaking is usually benign.

Dr. MacDonald: I do agree that ceramic-on-ceramic is the articulation of choice for the young patient—if you want to choose a bearing with higher failure rates, that has a substantial price premium, and that has unique and unresolved complications.

There is no perfect bearing.

Let’s start with longevity. To actually answer that question, you need large numbers, so avoid small case series and here is the advantage of registries, and Bill did a nice job of showing some of it from the Australian registry with 324,000 total hips. What is the best performing bearing in those 324,000 patients? Ceramic-on-highly crosslinked polyethylene at 5.1%.

What’s second best? Cobalt chrome-on-highly crosslinked polyethylene at 6.3%, and I would say a very distant and sad third, Dr. Walter, is ceramic-on-ceramic at 7.2%.

So, ceramic-on-ceramic is definitely not the bearing of choice if you plan on living more than 15 years.

In the young patient, ceramic-on-crosslinked polyethylene is that bearing of choice. This is not just in Australia. The New Zealand registry had 100,000 primary total hips in their registry (Sharplin et al, Hip Int2018). Ceramic-on-highly crosslinked polyethylene had the lowest all cause revision rate. They concluded the paper by saying it ‘… was the most durable and successful coupling used in primary THA irrespective of age, gender, and head size.’

When we say ceramic, we are really talking in 2017 about the Delta ceramic.