The Premier League's expert group of doctors are to examine the rules around concussion and head injuries as Tottenham Hotspur were forced to defend their decision to keep their goalkeeper, Hugo Lloris, on the pitch in the face of widespread criticism from Fifa, players' unions and charities.

Spurs insisted that medical staff had given the all-clear for the manager, André Villas-Boas, to allow Lloris to play on following a collision with Everton's Romelu Lukaku that left him unconscious, but the Professional Footballers' Association called for the decision to be taken out of the hands of medical staff and substitution to be made mandatory.

Fifa's chief medical officer, Professor Jiri Dvorak, said Spurs were wrong to keep Lloris on the pitch and the head injury charity Headway described the club's actions as "dangerous and irresponsible".

Fifa, which has hosted a series of academic conferences with other sports to establish a consensus on the issue, reiterated its advice that "any athlete with a suspected concussion should be removed from play, medically assessed and monitored for deterioration".

Fifpro, the international umbrella group for players' unions around the world, said it was alarmed that Lloris was allowed to play on. "Villas-Boas and his staff failed to protect the goalkeeper by allowing him to see out the remainder of the match," it said.

After the match, Villas-Boas hailed the bravery of his French goalkeeper, who collided with Lukaku in the 78th minute of the goalless draw: "Hugo seemed assertive and determined to continue and showed great character and personality. We decided to keep him on based on that."

Spurs insisted on Monday that their club doctor had given the go-ahead for Lloris to continue after assessing him and said a "precautionary" CT scan after the match had shown that he suffered no ill-effects.

The club's head of medical services Wayne Diesel added: "Once the relevant tests and assessments were carried out we were totally satisfied that he was fit to continue playing."

The north London club did not say whether they had believed him to be concussed at the time. Fifa's chief medical officer said there was a "99% probability that losing consciousness in such an event will result in concussion".

It is now understood that the Premier League Doctors' Group, which meets several times a season to share best practice and shape medical policies, will address the issue in the wake of several high- profile incidents that have involved Andros Townsend and Mathieu Flamini during the opening months of the season. Lukaku himself said he could not remember scoring his first goal for Everton after colliding with Joey O'Brien at Upton Park and being knocked out in the process.

Dvorak said that Lloris should have been taken off regardless of whether he wanted to play on. "The player should have been substituted," he said. "The fact the other player needed ice on his knee means it's obvious the blow was extensive. When he has been knocked unconscious, the player himself may not see the reality. We have a slogan: if there is any doubt, keep the player out."

Fifa's concussion guidelines, also agreed with the international rugby union, ice hockey and equestrian federations and updated this year, state: "With every impact to the head, it is important that you always think of concussion and watch out for it. If you feel a little out of sorts, but think you can still play, that may not be a good idea. The safest is: 'when in doubt, keep out'."

A Headway spokesman, Luke Griggs, said: "We are hugely concerned that a professional football club should take such an irresponsible and cavalier attitude to a player's health."

He said that guidelines from Headway and the National Institute for Health and Care Excellence stated that people should not play any contact sport for at least three weeks after suffering a concussion.

The PFA said it should be made mandatory for any player who has lost consciousness to be substituted. "When treating a player on the pitch, it can be very difficult to determine the severity of a head injury," said its deputy chief executive, John Bramhall. "It is important to take the pressure off the players, club medical staff, and the manager, removing the need for them to make a very difficult decision."

The Football Association pointed to regulations that say a player should not return to the pitch for five days after being substituted for a head injury, a recommendation that saw Arsenal's Flamini miss a Champions League game this season.

Its detailed guidelines say that a player who has been knocked unconscious should not play again that day. The rules do however allow for "a transient alteration of conscious level" following a head injury, which says a player can return to play following assessment by medical staff.