They hanged Del Fontaine at Wandsworth prison early on Tuesday 29 October 1935, three months and 19 days after he shot his girlfriend Hilda Meek having overheard her arranging a date on the phone and convinced himself she was seeing another man. Protesters picketed the prison the day they killed him, one told the papers that “they’re hanging an insane man”. Fontaine was a boxer, and had been a good one, twice the middleweight champion of Canada, but that was behind him. He had lost 11 fights in the last year, in the last he was knocked down four times in the first round.

When he was arrested Fontaine told the police “don’t think I’m crazy because I’m not”. But his lawyers argued that he was deluded. They called doctors, who said he had double vision, depression, insomnia, a loss of balance and that he had been bleeding from his ear. The welterweight world champion Ted “Kid” Lewis testified that Fontaine had “received more punishment than anyone I’ve ever seen”. The Guardian reported that their defence argued he was suffering from “a condition known as ‘punch-drunk’” which meant he didn’t know what he was doing.

It was the first time that phrase, “punch-drunk”, had appeared in the paper. It had been used for years already on the boxing circuit, but it had been formally identified only a few years earlier when a pathologist in New Jersey, Dr Harrison Martland, published a paper on his research into “punch-drunk syndrome”. It was so new that the journalists, and lawyers, struggled to describe exactly what it meant. The Guardian defined the symptoms as “a vacant look, far-away thoughts, and a general unbalance”. If Fontaine was suffering from it, he was a very extreme case, and undoubtedly had other mental health problems, too.

A couple of years after the Fontaine case, “punch-drunk syndrome” was renamed as “dementia pugilistica” in an article by JA Millspaugh and then, in 1949, the British neurologist Macdonald Critchley first described it in print as “chronic traumatic encephalopathy”, or CTE. If the medical understanding of exactly what “punch-drunk” meant was very vague at the time of the Fontaine case, it moved on so quickly that by 1959, the Guardian characterised the symptoms of CTE in a male boxer like this: “Speech and thought become more sluggish, memory deteriorates, the victim himself scarcely notices the gradual degeneration. His mood may swing rapidly from placidity to irritability.”

CTE can only be diagnosed after death – although there’s hope that may soon change – but it is hard to read that list of symptoms from more than 60 years ago without thinking about how similar they sound to the experiences of Steve Thompson, Alix Popham, Michael Lipman and the other rugby players who have already been diagnosed as having “probable CTE”.

On Wednesday the journal of Experimental Physiology published the latest research by the University of South Wales into the damage to the brain caused by playing professional rugby. The USW research, which was first reported by Michael Aylwin here in the Guardian in August, tracked a team playing in the United Rugby Championship through a recent season. They were tested before, during and after it. The results showed that all the players experienced a decline in blood flow to the brain and in cognitive function over the course of the season, despite the fact that there were only six recorded concussions among the group.

That doesn’t mean they have CTE, or will go on to develop it. But it does suggest that it is not just the concussions that are the problem here but the repetitive jarring of the brain. As the lead author, Prof Damian Bailey, told Aylwin in August: “You cannot interpret it any other way. You’ve got this noxious, cumulative, recurrent contact that doesn’t actually need to be anywhere near the head, so long as there’s some sort of torsional movement imparted to the brain. And it just builds up over time.” This is new evidence, but it isn’t news. Or it shouldn’t be. The link between small, repetitive blows and long-term damage was known about as long ago as the 1950s.

As a report in the Observer in 1956 noted, CTE “is not the knockout blow which causes the trouble, but years of steady pounding about the boxer’s head”. You can find similar observations in any number of articles, like this, for instance, published by the Guardian in 1984: “The second way in which the brain can be damaged is more insidious, changes begin to mount up as the number of fights increases …” or this, from 1994: “A second type of injury and the one many doctors fear more is the cumulative chronic effect suffered by a boxer over a career of being repeatedly hit in the head.”

Which begs two questions. One is why has it taken so long for rugby to begin to establish what has been widely accepted for years in boxing, especially when a player such as Popham says he believes he was taking “10 times as many blows to the head as a boxer does during a year” during his professional career? And the other, more important one, is: are the measures the sport has taken in the last few years, which have focused on diagnosing, treating and preventing concussions, addressing the real problem?