Study raises concerns about headers
10th February 2014 - Researchers are calling for more study into the impact of heading in football. In a paper published today they warn that not enough attention has been given to the long-term consequences of repetitive heading.
The literature review by a team led by Dr Tom Schweizer, director of the Neuroscience Research Program of St Michael's Hospital, Toronto, Canada, has been published in the journal Brain Injury.
More than 265 million people play football worldwide. In the UK, Sport England says football is part of the weekly routine for over 1.8 million people.
Due to the nature of the game, players are particularly vulnerable to head and neck injuries. Most are caused by unintended or unexpected contact. There is, however, significant concern in the sporting and medical worlds about the potential long-term cognitive and behavioural consequences for athletes who suffer acute or repeat concussions or multiple "sub-concussive" head impacts--blows to the head not causing symptoms of concussion.
Examining 49 research papers that studied the incidence of concussion in football, Dr Schweizer found that concussions accounted for 5.8% to 8.6% of total injuries sustained during games. One study found concussions sustained during football accounted for 15% of the total number of concussions in all sports.
Dr Schweizer says in a press release: "The practice of heading, which might occur thousands of times over a player's career, carries unknown risks, but may uniquely contribute to cognitive decline or impairment in the short- or long-term."
Most at risk
Research papers that looked at the mechanism of injury found 41.1% of concussions resulted from contact with an elbow, arm or hand to the head. One found that 58.3% of concussions occurred during a heading duel.
Female soccer players were usually found to have a higher incidence of concussions than men and the study found that defenders and goalkeepers are at greatest risk of suffering a concussion. Dr Schweizer says that for goalkeepers, the risk decreases as they get older and become more aware of where they are at any given time in relation to the goal posts. He said padding goal posts might be one way to reduce concussions in younger players who don't have such a developed sense of spatial awareness.
Studies on the long-term effects of heading found greater memory, planning and perceptual deficits in forwards and defenders, players who execute more headers. One study found professional players reporting the highest prevalence of heading during their careers did poorest in tests of verbal and visual memory as well as attention. Another found older or retired soccer players were significantly impaired in conceptual thinking, reaction time and concentration. Most of the few studies that used advanced imaging techniques found physical changes to the brains in players with and without a history of concussions.
Heading is believed to have led to the death in 2002 of the English footballer, Jeff Astle, described on the West Bromwich Albion website as 'a thunderous header of the ball'. A coroner reportedly found that the former player died from a degenerative brain disease caused by heading old fashioned, heavy leather footballs.