The comments come after Tottenham goalkeeper Hugo Lloris lost consciousness in an accidental collision with Romelu Lukaku during Sunday's 0-0 draw at Everton, with Spurs coming in for criticism after allowing the Frenchman to continue playing.
John Bramhall, the organisation's deputy chief executive, said in a statement: "When treating a player on pitch, it can be very difficult to determine the severity of a head injury.
"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.
"If anyone suffers a severe trauma to the head and loses consciousness, then they should be required to leave the field of play automatically.
"The PFA will continue to work with the stakeholders within the game, to evaluate what guidelines are currently in place and to see if and how they need to be improved to provide better protection for all those involved in the game."
Tottenham responded to the comments from Headway on Monday, with the club's head of medical services Wayne Diesel stating that he was "totally satisfied that [Lloris] was fit to continue playing".
Dr Justin Hughes, who runs the Sport Doctor website, was sympathetic to Tottenham's stance but believes football's governing bodies should look to follow rugby union's lead on diagnosing head injuries as the action continues.
"I do know some of the medical team at Spurs - it's a good team, we know that from the outcome with Fabrice Muamba in 2011," he told Goal.
"Premier footballers and rugby players are the most competitive people you will ever meet. As such, you won't be met with a welcome smile if you are about to take them out if the match - 'I'm alright doc, I feel fine, I'll play on', is a common answer.
"That presents a grey area and the management of that situation in the past has mainly come down to a decision based on knowing the player and personal experience of managing concussed athletes.
"Those decisions are difficult enough in a quiet medical room. In a stadium of 60,000 fans those decisions can be very hard to make. Add in the pressures from the manager's anxious chatter in your earpiece waiting for your answer, the ref needing to get the game going ASAP and TV cameras in your face it is far cry from the carpet clad rooms of Harley Street."
|SPURS DEFEND LLORIS STANCE
|“Once the relevant tests and assessments were carried out we were totally satisfied that he was fit to continue playing.”|
"The new pitch side assessment tools are a great help in rugby as you can actually score the responses a player makes off the field of play whilst the game continues," he continued.
"The key is being able to use the same thought process on the side of your pitch as you would in the doctor's office. The 'brain bin' effectively allows you to do that by removing you and the player off the pitch. If they recover and pass the tests then return to play. If they fail, they don't.
"The IRB have really worked hard on managing this in international and Premiership rugby. A panel of experts - brain surgeons, neurologists, sports doctors etc - also meet and produce a consensus statement on sports concussion definitions and management.
"The latest science and understanding is then implemented into policy and more recently to sport governing body rule changes to allow for a pitch side assessment of a player to be made. A 'brain bin' instead of the 'blood bin'.
"For instance, the substitution systems in rugby and association football are different. Changing those is a huge world wide task at FIfa level, but I think the principles of it could be adapted.
"There was nine or 10 mins of extra time added at Everton on Sunday. Crowds and TV producers don't like that.
"A temporary substitution and 'brain bin' in that situation could have avoided that and may have changed the final fit to play decision. Either he passed the pitch side assessment tests and returned to play or after five minutes he is not fit to play and the substitute stays on the park.
"Any suggested change needs to firstly protect the players and secondly to allow the game to continue.
"The rugby changes were implemented as a result of situations like [Sunday] and a feeling that we can make things easier for ourselves with a robust management system in place."