The future of medicine: are we close to the first human head transplant?

In a world where science advances by leaps and bounds, the possibility of a human head transplant, which once seemed taken from a science fiction novel, is being seriously discussed in the scientific community. But how close are we really to achieve this medical milestone?
The history of head transplants is as fascinating as controversial. The first experiments date from the early twentieth century, but it was in the 1950s when the Soviet surgeon Vladimir D claim made head transplants in dogs, exchanging the heads of two animals. Although these dogs did not survive long after the operation, their experiments laid the foundations for future investigations.

In 1970, the American neurosurgeon Robert J. White carried out a head transplant in a monkey. The operation was technically successful, but the monkey could not move because the spinal cord was not completely reconnected, and lived only a few days after the procedure.

In recent years, the Italian neurosurgeon Sergio Canavero captured worldwide attention by announcing his intention to perform a human head transplant. Despite his statement that the technological barriers had been overcome, the scientific community received their statements with skepticism. To date, such procedure has not been carried out in humans.

The Chinese surgeon Xiaoping Ren has also been involved in the research of head transplants, conducting experiments in mice and monkeys. Although it has demonstrated the possibility of reconnecting the backbone, nerves and blood vessels, the application of this humans in humans remains a topic of debate due to the enormous ethical and technical implications.

The reconnection of the nerves at the spine level is an extremely complex and delicate process, which represents one of the greatest challenges in neurosurgery. The spinal cord is a nerve beam that transmits signals between the brain and the rest of the body, and is protected by the spine. Each spinal nerve emerges from the marrow through spaces between the vertebrae.

To reconnect the nerves, surgeons must meticulously align the ends of the nerves cut. This implies joining the axonal nerve fibers, which are responsible for transmitting electrical signals, and ensuring that the environment is conducive to nerve regeneration. The nerve regeneration is a slow process and may not always be successful, since the nerves must grow and find their right path to restore adequate connections.

In the context of a head or body transplant, the reconnection of the spinal cord is even more challenging due to the amount of nerve connections that must be restored. Advances in techniques such as electrical stimulation, stem cell therapy and tissue engineering are being investigated as possible ways to improve the regeneration and functionality of the nerves after an injury or surgery.
The idea of transplanting a head - or rather, a body to a head - raises numerous ethical and technical questions. The main barrier is the reconnection of the spinal cord, a challenge that has not yet been overcome. Although it has been achieved in animals, the subjects become tetrapléjicos, indicating that we are still far from a functional solution for humans.

In summary, although the human head transplant remains a subject of fascination and controversy, current science is not prepared to carry it out in a safe and effective way. However, advances in regenerative medicine and neuroscience could, someday, make possible what seems impossible today.