Professor Dai Jianwu, who heads the team, said he was "very confident" the pioneering technique could one day help paralysed people to walk again.

"It will help not only patients with spinal cord injuries, but also those with facial and sciatic [hip] nerve injuries, too."

The spinal column is a mass of nerves that connects all parts of the body to the brain. Spinal-cord injuries are a major cause of paralysis.

The groundbreaking biomaterial that lies at the heart of the treatment is - for now - called LOCS+CBD-BDNF; it is so new that the scientists have yet to think up a snappier moniker.

"We were thrilled by the new material's healing effects," Dr Han Sufang, assistant researcher at the CAS' State Key Laboratory of Molecular Development Biology, said. "The dogs' recovery was fast, obvious and stable."

Han, the lead author of a paper on the surgery published this month in the journal , said: "[The dogs suffered] one of the worst kinds of spinal-cord injuries to suffer, because the connection was totally severed."

However, after the transplant with the new biomaterial - plus exercises to strengthen their legs and regain their balance - the dogs were able to stand on all fours unaided, Han said. "Some even took a walk."

The medical condition of each dog was closely observed for up to 38 weeks - far longer than usual animal experiments - so the long-term effects of the treatment could be recorded.

Han described the healing process as both sophisticated and delicate - "like building a high-speed rail".

She said the biomaterial worked by building a kind of scaffold (LOCS), like a rail, which allowed the broken ends of the cord to be reconnected. The rail was then supported by chemical molecules (CBD), that bounded together like pillars supporting a bridge.

Then the biomaterial would provide a brain-derived neurotrophic factor (BDNF) from proteins that had a stimulating effect and helped to guide the growth of new neurons across the "bridge".

The scientists found using the biomaterial was easy; they had only to implant the biomaterial into the damaged cord for the healing process to begin.

The breakthrough is good news for doctors around the world; many hospitals do not operate on patients with spinal cord injuries because of the complexity of the surgery and the risk of causing additional damage.

Yet the study has its limitations. The biomaterial has been developed over more than 10 years, with Dai and his team carrying out experiments on rats before moving on to dogs. Without data from clinical trials, it remains unclear whether the new biomaterial will prove effective and safe to use on humans.

Han said the team were optimistic. "Developing a cure so paralysed patients can walk again is our ultimate aim."

In the United States more than 1.2 million people are paralysed because of damage to their spines - the second biggest cause of paralysis after strokes, according to some estimates. Some patients remain in wheelchairs for the rest of their lives.

Many people suffer less severe injuries leaving a partial connection between a person's brain and parts of the body.

Road traffic accidents, mishaps at work and sports accidents cause nearly 70 per cent of all US spinal cord injuries.

Professor Liu Yaobo, a neuroscientist at Soochow University, in Suzhou , Jiangsu province, said the research was important. While recent breakthroughs on spinal cord injuries had been conducted mostly on small animals, such as rats and mice, the data on dogs was "certainly of higher quality," he said.

However, scientists still had much work to do before clinical trials could start, including tests on animals that were closer to humans, such as monkeys, Liu said. "Spinal cord injury is one of the biggest medical challenges we face. There may still be many years, even decades, before it can be cured."