It’s the 77th minute of Tottenham’s match against Everton, and Everton striker Romelu Lukaku is chasing down a long ball.

Tottenham keeper Hugo Lloris gets there first and comfortably gathers, however as he collects the ball, Lukaku’s momentum takes him towards Lloris and his knee collides heavily with Lloris’ head.

Cue a lengthy stoppage as Tottenham’s medical staff ensure that Lloris is fit to continue, and several long minutes later, a groggy looking Hugo Lloris trots back onto the pitch.

But was he fit to continue?

It is the moment which has thrown a media spotlight onto the long term risks which sportsmen take when continuing to play following a head collision.

The current FA guidelines state that a player who has suffered a head injury cannot continue playing “without the clearance of a qualified medical practitioner.”

Despite Lloris temporarily losing consciousness following the collision, Tottenham’s medical staff, after much discussion, cleared him fit to play.

However manager Andre Villas-Boas and the medical staff have come under fire for allowing Lloris to continue, as a player could be risking long term brain damage if they continue playing with a concussion.

Speaking to the BBC, brain injury charity Headway stated that: “when a player suffers a blow to the head that is severe enough for them to lose consciousness, it is vital they urgently seek appropriate medical attention. A physio or doctor treating a player on the pitch simply cannot accurately gauge the severity of the damage caused to the player’s brain in such a setting as there may be a delayed presentation of symptoms.”

It is not just football in which this is a concern, however.

In August, over 4,500 former National Football League (NFL) players brought a lawsuit against the league, claiming that the long term damages of concussion were hid from the players, while violent play and ‘big hits’ were both promoted and glorified. A huge settlement of $765m (£490m) was reached, with the money put towards concussion-related compensation, as well as funding medical research.

In Rugby Union meanwhile, a recent change in the rules regarding how suspected concussions has already caused controversy, with Barry O’Driscoll, certified doctor and a former Irish international, resigning from the International Rugby Board (IRB) medical committee.

Previously under the IRB rules, a player with suspected concussion had to leave the field of play and take a week off.

This has now been replaced with the Pitch-Side Concussion Assessment (PSCA), which requires players to be checked for concussion symptoms, answer questions such as ‘where are we?’ and ‘what is the score?’, and complete a balance test, similar to those conducted in drink-driving incidents. If one question is answered incorrectly, four balance errors are made and the player shows one or more symptoms of concussion, the player is removed from the game.

O’Driscoll, in the summer of 2012 when the rules were first introduced, claimed that the IRB were trivialising concussion and sending concussed players back out into “the most brutal arena.”

The IRB however claims that the new rules are working, as evidenced by the drop from 56% to 13% of concussed players returning to the field.

The case of Australian player George Smith from this summer, however, has thrown the new rules into a murky light once more.

A head to head collision between Smith and British and Irish Lions’ player Richard Hibbard left Smith unsteady on his feet and, to the eye of many, concussed. Yet five minutes and a successful PSCA later, Smith was given permission to return to the field, a move which caused much dispute on the effectiveness of the new rules.

It is a difficult situation for the rule makers of sports involving physical contact. On the one hand, there is the desire to keep the physicality, as that is what makes the sport what it is and is what the viewers want to see. On the other hand, the players’ health and safety must take priority, and in sports such as American Football where head-to-head contact is frequent, the removal of a player due to a suspected concussion could see several players leaving per game.

Finding the balance is key, and in sports such as football, American Football and rugby, it looks like it’s not quite there yet.