A millionaire stockbroker is launching a campaign to improve the treatment of spinal injuries in the UK after he spent hundreds of thousands of pounds on private surgery for his son who had broken his back in a snowboarding accident.

Andy Stewart, whose son Paul was told he would never walk again after an Alpine avalanche last December, turned to private healthcare in Britain and America after experiencing “third-class” National Health Service facilities. The treatment, which included pioneering electrical pulse technology, has restored some mobility to Paul’s legs.

Now Stewart, 58, a leading racehorse owner valued at £80m by The Sunday Times Rich List, plans to work with charities and the next government to address underinvestment in the NHS.

“The NHS is third-class and totally inefficient,” he said. “Why don’t we understand in Britain what the top spinal researchers are doing? It’s bonkers.”

In his first interview since returning to Britain after his most recent bout of US treatment, Paul, 28, an entrepreneur who has represented England at hockey, said he took a shortcut to the slopes on the day of the accident. “Suddenly I was on a slab of snow moving down the mountain,” he said. “I tried to get off it, then to surf it, then everything went black. When I opened my eyes I couldn’t move my toes or feel my legs.”

He had plunged more than 200ft over a cliff and had to be winched up by helicopter before being flown to hospital in nearby Grenoble.

After an initial operation, he was transported to Stoke Mandeville hospital in Buckinghamshire, the leading NHS facility for spinal injuries, where some doctors said he would never walk again.

His family were urged to seek treatment in Florida. “The doctors said, ‘Why don’t you get on a plane to Miami, one of the spinal research centres of the world?’,” said Stewart, whose parents were both hospital consultants.

Paul was initially transferred to the privately run Royal Buckinghamshire hospital, which specialises in spinal injury rehabilitation. There he had up to four hours of physiotherapy a day (compared with one hour at Stoke Mandeville) and was able to swim 20 lengths daily. He eventually recovered enough muscle power in his legs to walk around on crutches.

“I was wheeled out of Stoke Mandeville, but I walked out of the Royal Bucks,” Paul said. Since then he has spent two months in America receiving groundbreaking treatment and physiotherapy at two Miami hospitals. This has resulted in him getting around with only a walking stick. The treatment included an electrical impulse machine, not widely available in Britain, to stimulate bowel and sexual functions. He is due to return to Miami next year.

It is groundbreaking remedies such as these that Stewart wants to be made available to all spinal injury patients in Britain. He plans to publicise and fund the latest research. “I cannot change the world or the NHS but I can focus people on learning from the best spinal research around the world,” he said.

“The University of Miami is doing stem-cell research on guinea pigs, which could lead to a breakthrough in spinal research; we want to share this knowledge and make it available in the UK.”

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