George North’s latest head injury and its aftermath was a step backwards for rugby’s attempts to deal with the issue, according to campaigners.

The Wales wing was injured playing for Northampton on December 3, but his club escaped punishment by the RFU and he is now free to continue playing.

North appeared to lose consciousness after an aerial collision with Leicester’s Adam Thompstone, but passed pitch-side checks and returned to play.

A Concussion Management Review Group (CMRG) ruled on Wednesday that there had been “sufficient evidence” to end North’s involvement in the match – but that Northampton did not “intentionally ignore the player’s best interests”.

Northampton have therefore avoided a potential misconduct charge, leading to renewed scrutiny over the sport’s handling of head injuries.

“It’s hugely disappointing to see that Northampton have not been held to account for the handling of George North’s injury as it was a chance to make a statement and remind clubs, players and fans how serious an issue it is,” said expert sports injury lawyer Ian Christian.

“The findings and lack of punishment feel like a backwards step with the experts stating that Northampton could and should have done more to prevent North returning to the playing field.”

Irwin Mitchell lawyer Christian helped the Rugby Players Association (RPA) draw up their concussion protocols, and slammed a missed opportunity for further improvement with North’s latest head-injury incident.

Christian added: “This was an opportunity for the panel to make a statement about concussion and the importance of a safety first approach and it has been wasted.”

The first-ever concussion review panel released its findings on Wednesday, after 16 days of deliberations. The RFU professional director Nigel Melville and Premiership Rugby’s rugby director Phil Winstanley were joined on the panel by independent chairman Dr Julian Morris.

While offering nine recommendations for alterations to mid-match Head Injury Assessments (HIAs) and general concussion protocols, the panel stopped short of imposing any sanctions on Northampton – despite accepting North should not have returned to the field against Leicester.

Bosses at brain injury charity Headway were among those to express alarm at the outcome of the review.

“We are concerned with these findings,” Headway chief executive Peter McCabe said.

“Despite the CMRG reporting that the club followed concussion protocols and that the medical team had enough evidence available to them to make a decision, North, a player with a history of concussion, was allowed to re-enter play following the assessment.

“Serious questions have to be asked regarding the protocols: are they fit for purpose and are they being properly enforced?

“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.”

Leading concussion campaigner and former Scotland star John Beattie admitted he fears for North and other young players’ long-term health.

“We can’t have a game where the end-product is a brain-damaged super-human who’s made a bit of money,” Beattie 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.”

Wales wing North spent six months out of the game in 2015 after a series of head injuries.

Replays of the incident in Northampton’s 19-11 defeat at Welford Road suggested North had been knocked unconscious, but Saints have stressed that not all of the angles of the replay were available at the time of assessment.

Evidence presented by Northampton also stated that the Wales international denied any loss of consciousness, had immediate recall of events and stayed motionless due to concerns for his neck pain.

North, who has since been examined by an independent specialist, has not displayed any concussion symptoms following the incident and could return to action against Sale on Friday.

Among the recommendations outlined by the CMRG are an instruction for the full 13 minutes allocated to HIAs to be used unless there is clear reason to shorten it and that the team doctor must review video footage for permanent removal criteria both before commencing and after completing the HIA.

“The CMRG’s view is that there was sufficient evidence to conclude not only from the video evidence but also North’s history and risk stratification that he should not have returned to the field of play,” the review findings read.

“Northampton Saints medical team has accepted that North may have lost consciousness and therefore should not have returned to play.

“The CMRG considered the welfare of North was always at the centre of Northampton’s actions, and does not consider that the medical team (or the club) failed to complete the HIA protocol nor intentionally ignored the player’s best interests.

“In addition and although not a determining factor, the CMRG is aware that the player appears to have had no residual effects in the short term.

“For the above reasons the CMRG will not be imposing any sanction against the club or any of its individuals as a result of this incident.”

The RPA reacted to the findings of the review by describing the “breakdown in procedure” that enabled North’s return to play as a “significant failing”, adding that it would have preferred disciplinary action to have been taken.

“While we feel that sanctions would have sent a clear message about the gravity of concussion mismanagement, we welcome the recommendations outlined in the report,” the RPA statement added.