Ren Xiaoping, who once vowed to perform the world’s first human head transplant, has operated on a patient’s severed spinal cord in a 12-hour landmark operation in Moscow, according to the Chinese surgeon and Russian state sources.

Ren said the procedure was carried out at the Sklifosovsky Research Institute for Emergency Medicine in Russia last week.

“It was our Guangxi University of Chinese Medicine Second Affiliated Hospital and the Russian team working together,” Ren told the South China Morning Post on Thursday.

According to an article quoting Ren and published in the New Scientist on Wednesday, the team removed a segment of spinal cord that had been severed by trauma three years earlier and replaced it with a segment from a brain-dead donor, using microsurgery and polyethylene glycol (PEG), a substance that helps fuse cell membranes for the “world’s first spinal cord transplant”.

“The surgery was completed on October 14-15, lasting 12 hours. The patient’s condition is currently stable,” he said.

Ren did not answer when asked if the surgery was a “world first” but said he had performed a series of Russia’s first transplant surgeries at the centre.

Moscow mayor Sergey Sobyanin posted on Telegram on October 16 that “a patient who was originally at risk of complete paralysis has been given a chance to recover. Now, he is feeling well.”Russia’s Tass state news agency made a similar statement the evening, saying Chinese doctors had been involved and medical technology was shared.

There has been no further update on the surgery or the patient. Further, no peer-reviewed paper or clinical data on the surgery has been published.

The Sklifosovsky Research Institute for Emergency Medicine is one of the oldest in Russia and the largest multidisciplinary medical practice centre in Moscow.

In China, Ren is a well-known surgical and transplant specialist. In 1999, while studying in the United States, he took part in the world’s first hand transplant surgery.

After returning to China, Ren was director of the Hand and Microsurgery Centre at the Second Affiliated Hospital of Harbin Medical University.

In 2015, he announced he would cooperate with Italian neurosurgeon Sergio Canavero to complete the world’s first human head-transplant surgery within two years. But the surgery did not go ahead because of medical community concerns about ethics and backlash from the public.

Ren said he had done head transplant experiments on monkeys in 2016, and the following year said he and Canavero had created a surgical model for human head transplant surgery on two cadavers.

In 2019, he joined the Second Affiliated Hospital, Guangxi University of Chinese Medicine, the institution that last week collaborated with the Russian Medical Centre.

According to an announcement on the Russian hospital’s website, the recent spinal cord transplant surgery continued an ongoing joint upper limb transplant project between China and Russia. Guangxi University of Chinese Medicine’s website said Ren had led teams to Russia for clinical cooperation multiple times.

In April last year, he and the Russian National Emergency Medical Centre performed Russia’s first allogeneic, or donor-derived, hand transplant, according to the Chinese hospital’s website.

Since the first case, Ren has completed six difficult allogeneic hand transplant surgeries in Russia.

At the 17th Congress of Russian Surgeons in Moscow on October 12, Ren was awarded the “Mission Award” for outstanding Russian doctor.

The certificate in Russian, signed by Deputy Prime Minister Tatiana Golikova, said: “You successfully performed a groundbreaking surgery, saving the patient’s life.”