Holidaymakers should be aware of the dangers of diving into shallow water and the risks posed by water parks, a spinal surgeon has warned.
"A moment of madness" can lead to major injuries and paralysis, which often can't be reversed, says Evan Davies, from University Hospital Southampton.
He recently operated on a patient who had fractured his spine diving into hidden rocks in Croatia.
Another man snapped vertebrae in his neck on a water slide in Spain.
He was seriously injured in the incident and could be left paralysed.
Mr Davies, a consultant spinal surgeon, urged people going on holiday to look out for potential risks, because "life can change in an instant".
'Make your own assessment'
"What can often look on the face of it to be a quick and innocent thrill on these attractions can have potential to cause significant injury - that is something any impact head-on at high speed can cause.
"My message would be to remember that health warnings won't be high on the agenda at many holiday attractions and destinations and, in many countries, regulations and monitoring can vary greatly," he said.
"So, carry out a quick assessment of your own when visiting attractions such as water parks and, if you have a doubt about safety, avoid it."
Mr Davies said rarely a year went by when he did not treat the consequences of shallow diving.
He said it was important people understood the dangers of diving into water in places they did not know - and ending up crashing head-first into rocks.
"I have just recently operated on my first patient of the summer who fell foul of this," he said.
"And there will no doubt be more and, sometimes, no level of surgery can recover the damage caused in a moment of madness."