Mr Spiridinov, however, is more optimistic.
“If I have a chance of full body replacement I will get rid of the limits and be more independent”, he said.
Stage one involves cooling the patient and donor’s bodies in order to prevent the brain cells from dying during the operation.
Next, the neck is partially severed and the blood vessels from one body linked to the other with tubes.
Matthew Crocker, consultant neurosurgeon at St George’s Hospital, London, said every section of the operation has a grounding in current science and practice – at least in theory.
“Excluding blood vessels that supply blood to the brain then restoring them with tubes is very well recognised”, he told Sky News.
“Lowering the temperature of the whole body head and brain to between 10 and 20 degrees, usually around 15 to 17 degrees, is a very well recognised technique used for complex neurosurgery or cardiovascular surgery in which there is an expectation that the brain will be starved of its blood and oxygen supply for a substantial period.”
Stage two sees the spinal cord cut with an extremely fine blade to minimise damage.
The donor head is then removed, placed on the recipient’s body, and the spinal cord fused back together again using polyethylene glycol, a compound used both in medicine and industrial manufacturing.
Mr Crocker said: “The idea of cutting the spinal cord sharply rather than bluntly has a little medical support. The only well recognised success with spinal cord injury surgery came from a man who had a stab injury rather than a blunt injury.”