Birmingham Metal on Metal vs alternates with highly crosslinked polyethelyne

[wcummings]

what does the literature show?  which is better?

[John C]

You pose a very good question. Rather than trying to give a meaningless simple answer, I would suggest some things to consider when you are looking for an answer.
When you ask which is better, you are asking about published results. Part of the challenge in that approach is that results will vary a great deal between different surgeons. If you are going to look to the literature as you say, you have to decide whether you are going to look at larger studies like the national registries which will show you the average results among a large number of surgeons, or whether you want to look at the results for single surgeons, which might vary quite a bit from the combined results of many surgeons of varying skills and experience. Hip resurfacing surgery and results are much more dependent on the surgeon's technique and experience than many other surgeries. If you want to see the potential good results of resurfacing, you might consider restricting your research to surgeons who specialize in this procedure, rather than larger studies that will include surgeons who tried resurfacing a few times and then went back to doing THRs.
The only poly resurfacing device that I am aware of in current use (though there may be others that I am not aware of) is the Synova. I have read that Dr Pritchett in Seattle is the only surgeon using this device. I read his answer to your question, which basically said that if you are a large male, he might suggest that the metal on metal BHR is better. If the patient was a smaller female or there was a concern with metal ions, then he felt that the Synova might be the better solution. In other words, he felt that the answer to your question depended to a large degree on the patient.
One other variable to consider is whether you want to restrict your question to only the BHR brand on the metal to metal side of the equation. There are other metal on metal resurfacing devices out there that are the choice of a few of the top resurfacing surgeons. You might think about whether you want to add these to your comparison, so that you can include these top surgeons in your quest. If you do, it would be even more important to look at the individual surgeons results with these other devices, as opposed to something like a national registry which would include inexperienced surgeons who tried resurfacing a few times with different devices, with mixed success. Their results, when mixed in with a large study, will have an affect on how various brands will appear in studies that combine the results of many different surgeons.
So my answer to you is that it is not a simple apples to apples comparison that you can determine by looking at a couple of mega studies in the literature. In order to approach answering your question, at the very least you must look at the published results of the individual surgeons you might consider using, along with the specific device(s) that each surgeon uses, as well as the characteristics of the patient going into the surgery.
Like many of on this forum, I spent many months and many hundreds of hours researching the basic question you are asking. Good luck in your search, and please come back to the forum with what you find.

[catfriend]

I think John C gives a very good answer. But what do you mean by better? Let me put it this way: which is a better screwdriver, a slot head or a Phillips head? It depends on the screw. IOW the best device for one patient may not be the best device for another. There are men on this site who have received BHRs from Dr. Pritchett. I'm a woman who has received the Synova. And, yes, there are other devices. Different devices for different patients.

If you are looking in to HR my suggestion would not be to doctor shop based on device used, but to find an experienced HR surgeon you are comfortable with and ask him/her which device does he/she recommend for you, and why.

[karlos.bell]

 :) If the device is correctly installed young or old - male or female the results speak for themselves. Research the results not the material and summarize from facts. It is the surgeon also making the result. Lots of variables. Good luck.
Cheers K 8)