Does cricket have a concussion crisis?

After Phillip Hughes' death in 2014, Peter Brukner, the Australian team doctor, and Tom Gara, a historian at the South Australian Museum, conducted an analysis, funded by Cricket Australia, of how common fatalities were in the sport. Until then, no national boards had ever compiled numbers on how many players were killed while playing the game, either at amateur or professional level. Gara spent weeks labouring over newspaper archives from Great Britain and Ireland, Australia and New Zealand, going back to 1850. Brukner swiftly learned that "deaths were more common than I thought".

The authors identified 544 cricket-related deaths in Australia, New Zealand, Great Britain and Ireland: an average of around 3.25 per year. The true figure is likely to be considerably higher: their search only covered three cricketing nations, and the Australian coverage was incomplete. The deaths were split about equally between formal and recreational games.

The macabre list of deaths in cricket the researchers compiled included a spectator being killed by a ball hit into the crowd by his son; a fielder killed by the impact of a bat hitting their chest; and a boy killed by standing too close to a teacher demonstrating a shot. But about 80% of the fatalities recorded were caused by the impact of deliveries striking batters above the waist, with a significant majority of these hitting the heart or higher. Gara, a committed club cricketer "expected to find perhaps 20-30 deaths" sustained playing cricket in Australian history. Instead, he found 176. "I am still playing cricket and will continue to do so for as long as I can, but I am much more careful."

Batting for Marylebone Cricket Club against the touring West Indians in a first-class match at Lord's in 1976, England opener Dennis Amiss received a blow on the back of the head from Michael Holding, one of the world's most ferocious quick bowlers. Despite the blow, Amiss continued to bat. He hit 203 against West Indies in a Test later that summer, defying Holding and underlining his status as one of the finest players of fast bowling in the world.

Yet he retained uncomfortable memories of being hit. After World Series Cricket - the breakaway competition featuring many of the world's leading players that launched in Australia in 1977 - signed him up, Amiss, who was 34, feared the consequences of suffering another blow.

"I knew that I would be facing a lot of Australian and West Indies bowlers who would be delivering the ball at 90mph," Amiss recounted to the Daily Telegraph. He reached out to a motorcycle helmet manufacturer in Birmingham and asked him to make an adapted helmet to absorb potential blows, using conventional fibreglass with a polycarbonate visor. "He came up with something lighter than the fibreglass motorcycle helmets around in those days. It had a visor that could withstand a shotgun blast at 10 yards," he recalled. Initially, the design covered a batter's ears with unforeseen consequences - "we had a spate of run-outs". A later model solved the problem by incorporating an equestrian design.

When Amiss arrived in Australia at the end of 1977 with his customised motorcycle helmet, he became the first player to wear a helmet in a professional game. A month into World Series Cricket, the Australian batter David Hookes was struck in the jaw by the Caribbean quick Andy Roberts. He crashed to the ground, dripping blood.

It was the moment the helmet went from eccentricity to necessity. As Hookes had surgery - depriving World Series Cricket of one of its most attractive cricketers for the next five weeks - Kerry Packer, WSC's backer, ordered a batch of Amiss' helmets to be flown out from Birmingham, hoping that they would help protect his other assets.

As word of Hookes' accident got out, Tony Henson, the owner of Sydney and Surfers Paradise, a company specialising in equestrian caps, sensed a business opportunity. Henson asked a colleague, Arthur Wallace, to arrange a meeting with World Series Cricket representatives, as Gideon Haigh recounts in The Cricket War. Wallace returned from his meeting saying, "It can't be done, Tony. They want us to make something that can withstand half a house brick at a hundred miles an hour."

But it could be done: helmets could at least deflect blows and lessen their impact. In the months ahead, helmets - most initially without visors to protect players' faces - became ubiquitous at the top levels of the game, and rapidly spread through cricket's ecosystem as they became more affordable.

What began as an emergency solution to the dangers of facing the quickest bowlers in the world turned into one of the biggest improvements in player safety in sport. "Helmets basically wiped out the most common cause of fatality, which was a blow to the head," said Brukner. "Since the advent of helmets, I don't think there's been a death from a direct blow to the head. Helmets are very good at protecting you from death. The reason people die when they're hit in the head is that it causes a bleed in the brain, and that's the thing that kills them - that's the thing that you're protected from by a helmet."

Research conducted by Brukner and Gara shows how much safer helmets have made players. Over the course of the 1970s, there were nine recorded fatalities in Australian cricket - five in organised games and four in informal ones. Over the following 36 years, from 1980 to 2016, there were only ten recorded fatalities, with just five in the 26 years from 1990, when wearing helmets became the norm even at recreational level. And so the growth of helmets ought to be acclaimed as World Series Cricket's most important legacy - an innovation that has saved dozens of cricketers' lives since.

The next catalyst for cricket to take head injuries more seriously was the death of Hughes. StemGuard helmets were developed swiftly after: these have a neck-guard made from foam and plastic that is attached to the helmet.

In an Ashes Test at Lord's in July 2015, eight months after Hughes' death, the Australian opener Chris Rogers was struck by a short ball from Jimmy Anderson. It hit him behind his right ear and landed on his StemGuard. Rogers was one of the few players then wearing the new protection. Brukner told Wisden Cricketers' Almanack, "We both said to each other afterwards, if he hadn't been wearing it, who knows what would have happened?"

Yet neck guards are still not compulsory around the world. "It still amazes me that some cricketers don't wear them," Brukner says. When Steve Smith was hit on the neck by Jofra Archer in 2019, he was not wearing a StemGuard.

Alongside a change in technology, changing the laws of the game can also help to protect players. The introduction of concussion substitutes - first used in Australian domestic cricket in 2016, and in Test cricket in 2019 - may have reduced the number of concussions indirectly. In many cases concussions are thought to be caused not by a single blow but by repeated ones. Concussion substitutes help to destigmatise a player retiring hurt after a head injury, ensuring their teams aren't penalised. In this way concussion substitutes help to reduce the risk of second impacts after an initial concussion, which could be very serious or even fatal.

Yet, with neck guards and concussion substitutions alike, the puzzle is why safety measures that mitigate risk have not been embraced the world over. Domestic competitions in most Test-playing nations still do not allow concussion substitutes.

While direct fatalities in cricket remain extraordinarily rare - less than the chances of dying in the car on the way to a game, Brukner notes - death is not the only risk associated with suffering a blow to the head. Across American football, football, rugby and a range of other sports, recent years have highlighted the long-term effects of repeated blows to the head. These may be related to "sub-concussive" events: blows to the head that do not directly lead to concussions. Repeated impacts to the head - from heading a football to collisions with opponents in American football or in rugby - can lead to degenerative brain injury.

In July 2017, a study examined the brains of 111 deceased NFL players; 110 of them showed signs of a degenerative disease, Chronic Traumatic Encephalopathy (CTE), believed to be caused by repeated blows to the head, of the kind that routinely occur in NFL games. About 20-45% of professional American footballers may be affected by CTE during their lifetime, explains Thomas Talavage, a concussion specialist at Purdue University. In 2015, a class-action lawsuit settlement between the NFL and more than 5000 former players provided up to $5 million per retired player for serious medical conditions associated with repeated head trauma. A range of other sports have also faced lawsuits.

Cricket has been warned. Just because players are rarely killed by bouncers, there is no guarantee that bouncers will not have catastrophic repercussions for these players later in life. A 2020 study by a group of scientists, including John Orchard, Cricket Australia's chief medical officer, identified situational factors associated with concussion in cricket based on video analysis of elite Australian men's and women's matches. It found that 84% of head impacts occurred to a batter on strike against a pace bowler, with most of the others sustained by close fielders. No deliveries by spinners in the study led to batters sustaining concussion, showing how lower ball speeds reduce risks.

The evolving science has shown that, even as the number of deaths has declined, the ultimate danger of head injuries in sport is greater than previously assumed. The trajectory is unmistakable. "Concussions have become much more common in cricket over the last ten or 20 years," says Brukner. This is not simply the result of increased focus on concussion. "Since the advent of helmets, a lot more people are being hit in the head."

There are myriad theories for the increase in head impacts and concussions. Batting technique against short bowling is said to have deteriorated; the protection offered by helmets - and the extra time it takes to move their heads while wearing them - has been blamed for batters being less adept at ducking. Limited-overs formats are blamed for encouraging batters to hook the ball more compulsively. Helmets also may have liberated bowlers to use the short ball more aggressively. Worldwide, improved strength and conditioning, some believe, has enabled players to bowl up and around 90mph now more frequently than before. And there is simply more cricket played now.

The experience of Australia suggests that concussions have been systematically underreported. In the men's professional game, there was on average only one concussion per season recorded in the decade until 2014. Following Hughes' death, Cricket Australia commissioned a study by La Trobe University, whose findings were published in 2018. They counted 92 head impacts in men's matches in Australia between 2015 and 2017; 29 of them were diagnosed as concussions. As the authors of the study observed, "The rate of concussion in cricket is higher than previously appreciated."

The La Trobe figures equate to a head impact every 2000 balls and a concussion every 9000 balls in male domestic cricket. These figures suggest more than one head impact per Test match that runs the full five days, and more than one concussion for every four such Tests. Assuming head impacts and concussions were sustained at the same rate in international cricket as the Australian domestic game, we would have expected there to be 39 incidences of concussions from 2015 to 2018 in Test cricket alone, an average of 9.75 a year. Overall, we could expect an average of 16 concussions and 75 head impacts a year throughout all men's international cricket involving the 12 Full Member nations.

Medical officials argue that, per ball bowled, Australian domestic cricket is likely to produce more head impacts and concussions than the average across the world. There are a number of reasons for this: pace bowlers in Australia tend to be faster, spinners deliver a lower share of overs, and the pitches tend to be quicker. As such, they estimate that, per delivery bowled, the number of head impacts and concussions per ball in all first-class cricket is about one-third of the Australian rate. Using this ratio, and the fact there were 1,012,160 deliveries in all first-class cricket in 2019, implies that there were around 169 head impacts and 37 concussions sustained in men's first-class cricket in 2019. Brukner does not think that cricket will witness the same prevalence of CTE in retired players as in sports such as American football and rugby, because there are fewer sub-concussive blows to the head in cricket: "We believe that cricketers are therefore not as much at risk of that long-term issue as those other sports."

It will be many decades until it becomes clear what damage, if any, Will Pucovski suffered from his ten concussions. "We really don't know whether he's at risk of long-term damage," said Brukner. "There's so much we don't know about concussion."

Extracted from new book Crickonomics: The Anatomy of Modern Cricket by Stefan Szymanski and Tim Wigmore (Bloomsbury, £18.99)