The dangers of concussion in sport were highlighted this week by Belfast coroner Suzanne Anderson at the inquest of Benjamin Robinson (14) who collapsed on a rugby pitch in 2011. She said he had died from "second impact syndrome" which occurs when when two concussive-type injuries are sustained in a short space of time. Evidence was given suggesting the teenager had incurred a head injury during a heavy collision at the beginning of the second half of the match but that he had played on for a further 25 minutes.
A concussion is a type of traumatic brain injury (TBI) caused by a blow or jolt to the head. Concussions can also occur from a fall or a blow to the body that causes the head and brain to move quickly back and forth. There is evidence that some victims of mild TBI in sport develop micro-haemorrhages on the surface of the brain. These are diffusely spread, suggesting concussion represents a global rather than a focal injury to the brain. Researchers have also discovered that in the milliseconds after impact, there is a sudden release of neurotransmitters. It takes time for this surge of electrical activity to calm, during which the brain needs to rest. In a sporting context, this means immediately removing the player from the pitch.
The International Rugby Board continues to back its pitch-side suspected concussion assessment protocol, under which a player is taken from the pitch for five minutes while their neurological function is formally measured, despite apparent evidence that top level players are being allowed to return to the playing field while appearing to be still visibly dazed.
But it is schools sport that requires the strictest rules. Concussion is almost certainly under-diagnosed: a lack of specific signs combined with the tendency for young players to minimise their symptoms work against accurate diagnosis. Nothing less than an irreversible removal from the field of play is required in order to protect those aged 18 and under from the permanent neurological sequelae now linked with concussive episodes in sport.