The National Football League (NFL) is the largest professional sports league for American football, one of the most popular sports in the US. Concussion is a constant danger in the sport, which involves numerous high impact collisions between players. Over time, multiple instances of concussive and sub-concussive trauma can cause lasting damage to the brain.

Between 2005 and 2007, Dr Bennet Omalu, a forensic pathologist, published papers linking American football to chronic traumatic encephalopathy (CTE), a degenerative disease caused by repeated brain trauma. The condition itself is linked to mental impairment, mood disorders and suicidal tendencies. After Omalu’s first paper was published, the NFL’s Mild Traumatic Brain Injury committee (MTBI) called for it to be retracted, describing the research as “completely wrong”. The NFL commissioner Roger Goodell was also dismissive of the findings.

Nevertheless, public interest in the matter led to a congressional inquiry in 2009, after which the NFL announced a comprehensive reform of its concussion policy. Among other things, players who were knocked unconscious by concussion were barred from playing for at least the rest of the day, and each game was required to have a 29-person professional medical team on hand. 

The NFL took further measures in the wake of a federal class action lawsuit representing more than 4,500 former players. As part of a settlement reached in 2013 and approved by the court in 2015, the League agreed to set up a US$765 million medical fund for more than 20,000 retired players, providing baseline medical support and treatment for neurological conditions. Additionally, players diagnosed with CTE before the settlement date became eligible for up to US$5 million in compensation.

In March 2016, the League publicly acknowledged the link between American football and CTE. Later that year, Goodell announced the Play Smart Play Safe initiative, which will see US$100 million donated to brain injury research and education. However, controversy continues to swirl over the safety of the sport and the adequacy of the NFL’s initiatives so far.

It is estimated that these initiatives will cost the NFL US$1 billion over a period of 65 years. However, it is likely that the actual costs will be much higher, especially in terms of the health impact on players. A 2016 study revealed that more than 40% of retired NFL players had signs of traumatic brain injury, putting them at high risk of developing neurological degenerative disease later on in life.

CTE cannot currently be diagnosed before death, as it involves the sectioning of the brain. Researchers from the VA Boston Healthcare System and Boston University studied the brains of 202 deceased players of American football and released their findings in July 2017. They found CTE present in 99% of the deceased NFL players and 91% of the deceased college football players. This sample was not random, as the relevant families had suspected brain damage, but they are still concerning.