Brain injuries are far too prevalent in sport, with many players ignoring warning signs of danger after a big knock, a new study has found.
Sport accounts for one in five traumatic brain injuries in New Zealand, with nearly half of those likely to have a high risk of complications.
Previous studies held sport accountable for about 15 per cent of head injuries but research published in the Journal of Science and Medicine in Sport this month shows that to have increased to 21 per cent.
Even so, Hutt Hospital nurse Doug King, who studied concussion in rugby, said, if anything, the finding of 21 per cent was too low, because roughly half of concussions were never reported.
"Awareness around the seriousness of head trauma is growing but not everyone is being captured by it. For some, unless there's a loss of consciousness they don't consider it to be a concussion, which isn't the case," he said.
The study showed sports-related concussions in New Zealand were high compared to other activities and other countries. Rugby, cycling and equestrian activities were the sports most frequently associated with brain injuries.
ACC figures show more than 4000 people a year suffer a brain injury while playing sports, claiming about $8 million for lost earning and rehabilitation. Of these about a three quarters were suffered playing rugby.
Former All Black Steve Devine said his professional rugby career was cut short because he didn't take head injuries seriously enough.
The halfback's career ended in 2007 after a decade playing for Auckland, the Blues and 10 caps for the All Blacks.
His head troubles started five years earlier while playing for the All Blacks.
After the knocks kept on coming, he was forced to take a six-month break in 2006. A swinging arm in an NPC match the following year led to doctors saying his playing days were over.
Devine said a lot of research and testing was being done around preventing head injuries but at the height of his career he would get knocked out and then continue playing.
"My career probably would have lasted longer under today's conditions."
He said doctors instantly reacted to players affected by concussion in professional rugby today but he still worried about players at junior and club level who didn't have immediate medical support.
"School boys' rugby is an area that we've got to look at improving," he said.
"If boys see their opposition or team mates struggling on the field or someone else is witness to it then they need to stand up and stop them," he said.
Professional jockey Sam Spratt is also no stranger to serious head injuries. A heavy fall a decade ago saw her walk away from the track for four years.
Even today with a long list of head injuries behind her, she still doesn't completely follow medical advice.
"It comes down to the individual person as to how they react to it but because it's your career, love and passion, you sometimes just don't listen."
She said a head injury was different to a shattered leg that ends with a cast and a wheelchair. "There's nothing to show for a head injury and if you feel fine it's easy to just get back in to it."
Racing rules require jockeys who suffer concussion to stand down for three weeks, but if knocks happened while training or at home it was easy enough to ignore it, she said.
- The Dominion Post
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