by Domhnall MacAuley, CMAJ Associate editor, in Monaco.
Concussion is the current big story. Football, Hockey, Boxing and even Cricket have their own internal debates addressing issues including, helmets, rules on return to play, and the use of substitutes. The major worry is Chronic Traumatic Encephalopathy. CMAJ recently published a practice primer based on the Zurich Consensus guidelines, which sparked some spirited responses. Controversial stuff. I had hoped Paul McRory, an international expert on concussion, would give us some answers in his keynote. He described advances in technology that allow us to measure impact from sensors in helmets and how telemetrics and video allow us to calculate the biomechnical forces in head deceleration, but there was little correlation between these various parameters and concussion. Even highly sophisticated MRI examination tells us little. McRory reminded us that current guidance on return to play focuses mostly on the neurocognitive function, but that concussion is a systemic complex with many components. Even the pathological findings in deceased ex athletes are difficult to interpret. There is no direct correlation between impact and the concussive response and, individuals appear to react differently in different circumstances. The only strong risk factors for concussion that have been identified appear to be previous injury, gender and a history of migraine-so there is not a lot we can do. Like many in the audience, I had hoped for a simple solution. There isn’t one.
The most recent Zurich guidelines created lots of discussion but McCrory pointed out that these guidelines are work in progress rather than the definitive answer. Research has produced lots of new information in recent years but, he concluded, we probably know less now than before.
I discussed this with Peter Larkins, a doctor and media analyst for Aussie Rules Football, who provides on the spot television analysis of injuries during games. He told me about changes to the rules of Aussie Rules football, which allow players to leave the pitch for 20 minutes for concussion assessment. It’s amazing that a governing body was prepared sanction such a long time out period; it’s a rule that should perhaps be adopted by other sports.
Showing data from the UEFA study of top European football clubs, Jan Eksrand (Sweden) shared some interesting findings on injury patterns in soccer. He showed how more injuries occur during matches than in training and how more injuries occur during matches lost than won. Each player has an average 1.8 injuries per season with 12% of a playing squad unavailable at any one time. It’s remarkable that clubs are prepared to share these data but, of course, sharing knowledge about injuries could help them all. Many sessions on injury management focused on accelerating return to play. But, before we could get carried away with rapid rehabilitation, one audience member reminded us that the role of collagen hadn’t altered in the 30 plus years since he was at medical school. We might have the best intentions but biology hasn’t changed.
On a lifelong journey from runner, through jogger, to shuffler, I’ve worn many of the shoes that Benno Nigg (Canada and Switzerland), a legend in the science of shoes, gait, and running biomechanics, used as examples of running shoe development in his keynote address. His talk fascinated me. With shoe design changes, pressure was unpredictable, insoles caused variable pronation and supination and almost all parameters were subject specific. Comfort, however, was the common factor - athletes seemed able to choose their own shoe. We still haven’t found the answer to the perfect running shoe and his penultimate slide called for increasing collaboration between epidemiology and functional science. A fitting conference epilogue.