May 01 2017

Surgeons Plan First “Head Transplant”

sergio-canavero-xiaoping-renYou should be skeptical – in general, but certainly of this specific claim.

First I should point out that such a procedure would be a body transplant, not a head transplant. The head would get a new body, because the head is the person.

This story has all the red flags of scam and pseudoscience. I am having a hard time figuring out exactly what the scam is. It may just be an exceptionally self-deluded surgeon, but it is instructive to identify all the reasons this claims is almost certainly nonsense.

Italian neurosurgeon Sergio Canavero has announced that he plans to perform the first “head transplant” by the end of 2017 in China on a Chinese national (as yet unnamed). He has been working with Russian patient, Valery Spiridonov, who has a muscle-wasting disease, but for some reason he is now moving his operation to China.

The primary reason for skepticism is that we simply do not have the technology to pull off this kind of operation. I have previously reviewed the history of head transplant research. I also wrote about Canavero in 2013 when he first started making such claims.

Disconnect Between Claims and Published Evidence

To the general public, who may not be familiar with how the institutions of science tend to function, when an expert claims to have done research and made breakthroughs, it can sound plausible, even compelling.  They may not realize what’s missing, and the magnitude of the claims being made.

Scientific progress is a collaborative effort. Long gone are the days when lone geniuses can do research in their homes for years or decades and make significant breakthroughs. This is because we have mostly picked the low hanging fruit, and now advances are incremental and require tremendous infrastructure and collaboration. It could take years for one lab to demonstrate one small piece of a larger puzzle.

There are also many stages to research before we get to clinical applications. The most significant breakthroughs tend to start with a basic science discovery, about some aspect of human biology that can potentially be exploited therapeutically. Most such new targets do not lead to treatments, something like 1% of the promising targets do. A lot needs to be understood about such new basic science knowledge of biology, and that will often involve the work of many labs and researchers. This new knowledge then needs to be translated into clinical treatments (literally called “translational” research).

If things are still looking good we progress to animal research, then preliminary human research, and finally rigorous human research. This is a 10-20 year process at best, and will often involve dozens if not hundreds or even thousands of published papers.

So, when someone claims to have made a breakthrough that would require this kind of research, we have to ask – where is the 20 years of supporting research, with the hundreds of published studies? Canavero has nothing. He claims he is about to publish such papers in respected journals (without naming them) but has nothing specific. Newsweek quotes him as saying:

“I can only disclose that there has been massive progress in medical experiments, which would have seemed impossible even as recently as a few months ago,” he said. “The milestones we have reached will undoubtedly revolutionize medicine.”

Again, no details, just hype. What kind of experiments are we talking about? If he is just deluded, I suspect he may be talking about surgical techniques. Maybe he is making progress in refining the surgery necessary to attach a head to a body, but that is only part of the challenge here.

Canavero defends his lack of publications with this poor analogy:

“It’s the same as with pharmaceutical companies. They conduct research for years and don’t publish anything, then at a certain stage they go out and inform the media and public.”

This analogy doesn’t work because even for new drugs that pharmaceutical companies are keeping closely guarded, there is a paper trail for the basic science. Drug companies typically will identify potential new pharmaceutical targets discovered by basic scientists working at universities, and then try to manufacture drugs to activate those targets. Their real expertise is in chemistry – tweaking the chemicals to have the desired properties. But even in the earliest stages of their research everyone knows what their biological target is. The real industry secret is the chemical. Before doing any human research, everything is disclosed about the properties of the chemical and its actions in the body.

The Iron Man Fallacy

As many comic-book fans know, the central plot hole of the Iron Man character (common to technology-based superheroes) is that he has discovered a fantastical new source of energy, that is clean, renewable, safe, reliable, and portable. He can implant a small energy factory into his own chest, and use it to power his Iron Man suit.

What he doesn’t do, however, is completely revolutionize civilization with his new energy source. The portable power plant is the thing. The Iron Man suit is far from the best use of that technology. If he really wants to help people, then give them clean energy.

We have a similar problem with Canavero’s claims. There are many technical challenges for what he is proposing, but the core problem is the spinal cord. In order to transplant a body, you have to sever the spinal cord and then attach the bottom of the cord from the recipient head to the top of the cord from the donor body. Without spinal cord and nerve regeneration, the body recipient would be worse than paralyzed from the neck down (worse because even some cranial nerves would be affected, unless they were also regenerated).

In this scenario the body might function as a life-support system for the head, but would otherwise be useless. The body recipient would not be able to move or to even breath. Let’s not even get into the issue of tissue rejection.

If Canavero has found a way to regenerate spinal cords, then using that technology first to perform a head transplant would be similar to using a revolutionary power source for personal body armor. Why don’t we first use it to fix the millions of people with spinal cord injuries?

We won’t even get to this question, however, because Canavero did not figure out how to regenerate spinal cords. First, he is a surgeon. He doesn’t even have the expertise to do the kind of research to make such a breakthrough. If he farmed-out this necessary breakthrough to another team, who are they and where is their research? Why aren’t they communicating with the community of researchers who are actively researching how to regenerate spinal cords? How have they managed to make decades of progress without anyone knowing who they are, or leaving any trace in the published literature?

If Canavero plans to just attach someone’s head to a donor body, without restoring a neurological connection between the two, then what does he think his advance is? How is this going to revolutionize medicine. I’m sure there are technical hurdles to physically attaching the head and the body. We can already attached blood vessels together, no problem there. We can fuse vertebrae, even insert an artificial vertebra and disc. The muscle attachments will be tricky, but nothing impossible there.

That leaves the spinal cord. So, either he has made an impossible breakthrough in spinal cord regeneration that he is failing to share with the world so that he can pull a dramatic stunt with a body transplant, or he has nothing meaningful to contribute. Having the specific surgical technique to attach a head to a body is of no use without the spinal cord regeneration.


The main mystery here is this – what’s the scam? I doubt he is doing this to attract research money, or lure in rich potential clients. My guess is that Canavero is simply a crank. He may be a skilled surgeon, but has a nutty idea about doing a revolutionary surgical procedure and becoming famous, and is missing the big picture.

I suspect this will go about as well as the endless claims for a free energy device. It won’t work. We’ll be given some lame excuses, and promises that the minor technical issues will be worked out. Maybe we’ll hear of Canavero again as he tries to keep his dream alive, but he will likely just fade away like the Orbo technology.

For those who might say, “Hey, let the dreamers dream,” sorry, that is not an answer. I have no problem with researchers pushing the envelope, chasing wild and unlikely ideas, and going against convention. Dream big  – go for it. Being a big dreamer, however, does not make you immune to reality or criticism. You still have to defend your claims, and be responsible for the claims that you make.

Being a “visionary” is not an excuse for making claims you cannot back up with data. It is no excuse for unethical behavior.

The fact is, when you make a visionary claim for a major breakthrough, your burden of proof is higher, not lower. That is always a clear sign of a crank, they use the revolutionary status of their claim to shield themselves from criticism and put off demands for evidence.

If you are truly a visionary who will revolutionize medicine, good for you. Now prove it.

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