A new American study suggests that people who participate in contact sports during their school years may be at an elevated risk of developing chronic traumatic encephalopathy (CTE), a condition associated with a progressive deterioration of brain function in later life.
In the past, the potentially brain-damaging impact of contact sports was predominantly linked to the most punishing of disciplines, like boxing.
In recent years, however, there has been a growing body of evidence that appears to connect a much wider range of sports which involve frequent incidents of mild head trauma and concussion to a variety of neurological conditions.
In South Africa, public awareness around this issue has been raised by the stories of former professional rugby stars like Joost van der Westhuizen, who has been diagnosed with motor neuron disease (MND) and Andre Venter, who suffers from a degenerative nervous condition called transverse myelitis.
Other rugby players who have been diagnosed with MND include Tinus Linee, who died of MND in 2014 aged 45; New Zealand rugby union fullback Jarrod Cunningham who died of the disease in 2007; ex-Sharks rugby player Ryan Walker who was diagnosed with MND at the age of 35; and former Natal wing Danny Delport, who was diagnosed in 2014.
Another famous sufferer of motor neuron disease include American baseball legend Lou Gehrig, after whom the most common MND, Lou Gehrig's Disease was named.
During a September 2014 interview with BBC Radio 5 live Joost said that he believes there could be a link between his rugby career and motor neuron disease as he was diagnosed with in 2011.
When asked if he had suffered concussions that may have damaged his brain during his career, Van der Westhuizen replied: "I broke my nose 16 times, that should say enough."
Read: Joost van der Westhuizen takes part in an exclusive MND drug trial
Experts say that between 5 and 10 percent of MND is genetic. The other 90-odd percent is down to environmental factors, of which regular concussions is one.
Enter traumatic encephalopthy, aka 'punch-drunk disease'
In the United States, another sports-related brain disease has come to prominence. A study by the Centre for the Study of Traumatic Encephalopathy at Boston University School of Medicine examined the spinal cord and brain tissue of 12 deceased National Football League (NFL) players who suffered from chronic traumatic encephalopathy (CTE).
“It is too early to be sure,” Dr Ann McKee, who led the study, said. “But it suggests a history of repetitive head or neck trauma may trigger this.”
First demonstrated in boxers as "punch-drunk disease", CTE results from repeated, mild head trauma as a result of blows to the skull. Collectively, these individually rather minor brain injuries can cause progressive damage to nerve cells and changes in the brain that ultimately lead to a slew of cognitive, emotional, behavioural and physical problems, many of which may only become apparent years later.
CTE shares similarities with other degenerative illnesses such as Alzheimer’s disease, Parkinson’s disease and Amyotrophic lateral sclerosis (ALS). Typical symptoms include short-term memory loss, depression, irritability, aggressiveness and suicidal tendencies.
Currently the disease can only be diagnosed after death.
In the United States, CTE has been associated predominantly with professional ice hockey and American football players, but increasingly also with other sports, including soccer, rugby, wrestling and field hockey.
The connection has not been without controversy, however.
Some neurologists have questioned whether the condition actually exists and in a 2014 editorial in the British Journal of Sports Medicine, two prominent sports physicians, Dr Jon Patricios and Dr Simon Kemp, pointed out that CTE has gained a lot of notoriety on social media networks and through high-profile lawsuits “in spite of an absence of evidence of established risks”.
They recommended further research into the field, arguing that “as physicians and scientists, we need to reclaim clinical decision making from the realm of media-driven and often frenzied public opinion”.
Read: Will Smith's new movie Concussion highlights the dangers of brain injury in American football
More concrete information about the connection between CTE and contact sports, including rugby, and school children, has come to light this year.
A paper published in the Quarterly Journal of Medicine in May suggests that “the association between exposure to head injury and increased risk of neurodegenerative disease, specifically chronic traumatic encephalopathy (CTE), is widely recognised”, and that “it is clear that it is the exposure to head injury which is associated with increased dementia risk, and not the circumstances or environment of exposure".
The implication is that CTE may not only be a problem in boxing, but also in those sports in which blows to the head are less frequent and usually accidental.
While acknowledging that few proven instances connecting rugby and CTE currently exist, the study offers the first detailed example of a former amateur rugby union player, who participated in the sport from his teens until the age of 50, experiencing many concussions and head injuries along the way.
He died six years after displaying the first symptoms of CTE and was diagnosed posthumously.
In a paper that appears in the December issue of Acta Neuropathologica, a team of US researchers present evidence for a significant incidence of CTE in men who played contact sports, including boxing, American football, wrestling, basketball, rugby and baseball in their youth.
Investigating brains that were donated to the Mayo Clinic Brain Bank in Florida, the authors found that “exposure to contact sports was the greatest risk factor for CTE pathology”.
They discovered signs of CTE in the brains of 21 out of 66 men (i.e. 32%) documented to have participated in contact sports during youth and young adulthood.
By contrast, none of the 165 men considered in the study who did not have a history of such sports showed evidence of the disease.
According to lead author Kevin Bieniek, “the purpose of our study is not to discourage children and adults from participating in sports because we believe the mental and physical health benefits are great”.
But he does stress that “it is vital that people use caution when it comes to protecting the head. Through CTE awareness, greater emphasis will be placed on making contact sports safer, with better protective equipment and fewer head-to-head contacts."
Read: Concussed rugby players are putting themselves at risk
What does the rule book say about concussion in rugby?
Regulation 10 of the World Rugby (formerly IRB) code says that any player suspected of concussion must be taken off and not allowed back on to the field during the match.
Read: SARU regulations on concussion 11 December 2015
There is an exception to the rule that applies to players in elite adult matches, series of matches or tournaments that have been approved in advance by World Rugby.
If they are suspected of having suffered concussion and can pass a series of tests lasting five minutes the player can be allowed back into the game.
It’s known as the Head Injury Assessment (formerly PSCA/Pitch Side Concussion Assessment) or the five-minute rule. It is said to be 84.6% accurate in determining concussion.
Barry O’Driscoll, a former medical adviser to the International Rugby Board, resigned in 2012 over what he saw as a reckless stance on concussion – referring to the introduction of the controversial five-minute concussion bin.
"We are sending concussed players back onto the field – brain damaged players," he said.
"We know now what's going on in the brain as soon as it is hit. The glucose metabolism, the oxygen uptake, the electrolytes ... are all thrown completely out. This is a brain in disarray. It's not functioning properly.
"The decision making is reduced, the cognitive function is reduced, and the emotions are thrown. What on earth is a person in that state going back onto the rugby field for?"
While in the past team doctors examined players on the pitch and decided if they needed to come off. This resulted in 56% of players who played on were later found to be concussed. The IRB says that figure is now 13%.
O’Driscoll told the BBC, “If they incorporate the 'five-minute rule' I think you're putting people with brain damage back on the field, and the arena they're going back into is brutal."
He warns that, like in the NFL, it was just a matter of time before injured rugby players started to sue World Rugby. Only then is something likely to be done.
Read: Brain disease is now linked to repetitive brain injuries in sport
How can contact sports players protect themselves?
Although it is not currently known how many players worldwide choose to wear headgear, Gerrard et al reported headgear use by 20% of rugby players in New Zealand.
At that time, it was reported to be mostly limited to forwards and a few backline players who were recovering from an injury or who had been concussed several times in the past
However, a study in the British Journal of Sports Medicine shows that it's not clear whether commercially available headgear will protect against concussion.
There were a number of reasons for not always wearing headgear. These were, in order of most cited, that headgear use is not mandatory, followed by not comfortable and expensive. Other popular reasons were poor ventilation and “it gets grabbed during play”.
Dr Mike Loosemore, the doctor for the British boxing team and a leading member of the medical team at the London Olympics, told Telegraph Sport that headguards are not only ineffective, they could create problems because they create an illusion of safety.
He explains that laymen think the blow itself creates the damage, whereas concussion results from a sort of neural whiplash as the whole head accelerates and the brain sloshes around in its capsule.
Read: What happens to the brain when it takes a blow?
Better pitchside assessment by 2020
In five years’ time academics from Sheffield Hallam university hope to introduce a pitchside eye test that will help to diagnose concussion in seconds rather than minutes. Retinal scanners reveal much about nerve fibres and vessels in the eye and changes could signify concussion.
Currently a series of subjective balance, memory and cognitive tests are done when a player has a suspected concussion injury. There is also an app that medics can use to spot concussion.
Another option that has been suggested for reform of the tackle is changing the rules to encourage players to tackle lower on the body of their opponent.
Note: Health24 contacted BokSmart senior manager Dr Wayne Viljoen with regards to the above findings and to inquire about how our youth can be further protected against concussions in rugby. His office has notified us that they are working on new guidelines, and that these will be made available to us early in 2016.
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