David Griffin still does not know if he will recover completely

Dave Griffin, 41, severed his spine when he was demonstrating a trampoline bounce to pupils at Llanishen High School in Cardiff.

Doctors feared he would be paralysed but just six weeks after the serious accident he is back walking, cycling and exercising in the gym.

But it may be another two years before the extent of his injuries are known.

Mr Griffin fell awkwardly and landed on his head, leaving him in agony on the trampoline during the lunchtime demonstration in April.

It took paramedics two hours to rescue him because they had to stabilise the surface of the trampoline.

I'm counting my blessings that I've made the recovery I have so far Dave Griffin

Mr Griffin said he has feared the worst because the lesion on his spinal cord mean there was no sensation between his head and his body.

"I realised that I was probably going to be a quadriplegic for the rest of my life.

"And then I thought of what a huge burden I was going to be on my family both financially and emotionally," he said.

"I was beating myself up over the fact that this one second of misfortune was going to ruin my family's life."

But six weeks later and following a life-saving operation in the University of Wales Hospital in Cardiff, Mr Griffin has made remarkable progress.

He is back on his feet and back home in Cyncoed in Cardiff with wife Ann and children Emily, six, and James, 11.

Feeling has returned to his legs but less so to his arms and Mr Griffin is working in the gym to try to rectify that.

Prognosis

"I'm counting my blessings that I've made the recovery I have so far," he said.

"There's still a long way to go in terms of rehab but the thoughts and prayers of so many and the goodwill shown by so many has certainly been an integral part."

Being a PE teacher has helped him get to grips quickly with an exercise regime to help speed his recovery.

But the injury has meant a disappointment for his children - a "trip of a lifetime" to Florida which they had booked for the summer has had to be cancelled.

"It's one of the injuries where the prognosis is really so uncertain," said Mt Griffin.

"Nobody can tell me what the extent of the recovery is going to be.