George North would be told to retire were he an amateur, says Dr Barry O'Driscoll

Wales wing George North has played 64 times for Northampton Saints since joining in 2013

Northampton Saints wing George North would be told not to play rugby again were he an amateur, says a former World Rugby medical adviser.

On Wednesday, a review panel ruled the club would not be punished despite finding North should not have played on after a head knock against Leicester.

It was the fifth blow to the head the Wales winger, 24, has had in two years.

"As an amateur you would say there is no way you must play again," Dr Barry O'Driscoll told BBC Radio Wales.

"As a professional player, and some people have very dangerous professions, it's not quite so simple.

"After four or five [concussions] you do consider it but I can fully understand because of his professional commitments, as it's his livelihood, he might be reluctant to."

Meanwhile, former Saracens captain Alistair Hargreaves, who retired in October because of a concussion injury, said the findings of the review are "a disgrace".

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'Enough is enough'

O'Driscoll had earlier suggested rugby union's authorities are "experimenting on players' brains" by failing to address concussion.

"They have had enough examples of how it has gone wrong to say 'enough is enough'," he said.

"If you have to take a player off to have a concussion assessment, you must suspect concussion and he must stay off. But they are experimenting in that part of the game that is the most brutal."

The Rugby Players' Association (RPA) said North's return to the field was a "significant failing", and believes sanctions would have sent a "clear message" about the "gravity of concussion management".

It added the recommendations in the report "must be adopted" to ensure North's case is an "isolated incident".

Former Scotland international John Beattie said he was worried for the future of young players, and they "have to be protected" from brain damage.

"We can't have a game where the end product is a brain-damaged super-human who's made a bit of money," the 59-year-old told BBC Radio 5 live.

"I know blokes my age and younger who have brain damage. I worry about George North. I think we need to be much more careful with players."

The report states North told medics he had stayed still after the incident, at Welford Road on 3 December, because he was "concerned about his neck".

He also "continued to deny any loss of consciousness with immediate recall of events", with the "only symptom recorded being neck pain".

Beattie said "the last person you should listen to is the player" as they are "trapped in a money-earning spiral".

North's concussion history

The Northampton back suffered four head blows in five months between November 2014 and March 2015, leading to a spell on the sidelines that lasted from 27 March until 29 August.

• 22 November 2014: North suffers first concussion in Wales' 34-16 defeat by New Zealand

• 6 February 2015: Suffers accidental kick to the head during first half of 21-16 loss to England, but after assessment returns to the field

• 6 February 2015: Receives second blow to the head in second half of same game, appears to have been knocked out but finishes match

• 27 March 2015: North is knocked unconscious scoring a try in Northampton's 52-30 win over Wasps

What are the rules?

• With suspected concussion, club doctors have 13 minutes to decide if a player can return to the field.

• All Premiership grounds and Twickenham have medical teams with access to replays to help that decision.

• Any player with confirmed or suspected concussion will be permanently removed.

Protocols 'not fit for purpose'

Despite describing video technology in concussion assessments as "a great idea", O'Driscoll said the system of dealing with such incidents is "not fit for purpose".

"These protocols are terribly poor, they're dangerous - they're putting brain-damaged players back on the field time and time again," he said.

"In community rugby, women's rugby, school kids' rugby, there's no such thing as a protocol test because it doesn't work. It's black and white with them, if they have to come off they stay off."

Peter McCabe, chief executive of brain injury association Headway, said "serious questions have to be asked" of the existing protocols.

"This incident sends out a confusing message around the issue of concussion, particularly for children who follow the example of famous players and favourite clubs," he said.

Sports injury lawyer Ian Christian said the panel's decision was "hugely disappointing", and a missed opportunity for rugby authorities to "make a statement".

"This isn't the first time George North has played on when all those watching thought he should be off the pitch, and it proves that players need protecting from themselves," he said.

Medics 'would never jeopardise a player's health'

Former England international Andy Hazell - who retired in 2014 because of a concussion injury - told BBC Radio 5 live player welfare is "100%" at the forefront of decision-making by club doctors.

"People forget that the medical team and the players see each other daily," he said. "There's a bond.

"The rugby community is a tight community. These are your friends, and people would never jeopardise a player's health."