"Soccer: Heading the ball linked to concussion symptoms"
February 1, 2017
A study was recently published in the journal, Neurology, that states intentional and unintentional head impacts that occur in soccer are each independently associated with moderate to severe CNS (Central Nervous System) symptoms. These symptoms range from slight pain and dizziness to symptoms such as feeling dazed, stopping play, needing medical attention, all the way to getting knocked out and losing complete consciousness on the field.
222 dedicated soccer players were utilized in this study and completed a 470 HeadCount questionnaire that focused on the amount and level of impacts, both intentional and unintentional, made on the field.
Researchers discovered that the players that reported heading the ball the most amount of times, were 3 times more likely to have such CNS Symptoms. While players suffering from 2 or more reported unintentional impacts were 6 times more likely to have symptoms than a player who experienced no impacts. Unintentional impacts meaning, any collision or fall on the soccer field.
"Soccer players 'are very unique in that they will predictably have repeated impacts to the head which we can characterize and quantify,' he said, which makes them 'an incredibly robust model system for looking at repetitive head injury.'"
The next vital step in gathering this information is to see just how exactly the brain responds to repeated injury long term.
For further detail: http://www.cnn.com/2017/02/01/health/soccer-headers-concussion-study/index.html
For the actual study: http://www.neurology.org/content/early/2017/02/01/WNL.0000000000003657
[neuroFit commentary, 2/17/2017] Does anyone remember doing repeated headers in youth soccer? I can remember heading drills being part of a summer soccer camp, but will I still have that memory in twenty years? I hope so. While the full list of the sports whose long-term players develop CTE is not yet complete, it seems that soccer has been added to the growing list that includes football and ice hockey. This Feb 2017 article in Acta Neuropathologica adds six post-mortem examinations of former professional soccer players (all showed signs of CTE) to the four post-mortem cases already in the literature.
While considering the combined topics of concussion symptoms and my misspent youth, I was reminded of a recent paper describing combined G-loading and vibration experiments, a case study describing the onset of Benign Paroxsymal Positional Vertigo in a small subset of subjects. In this paper, three of sixteen subjects reported onset of BPPV shortly after exposure to combined G-loading (+3.8 Gx) and vibration (8-16 Hz at 0.5 gx) in the Apollo-era centrifuge at NASA Ames. BPPV results from injury to the inner ear, whereby small fragments of otoconia break or detach from the otolith organs and end up floating in the long arm of the semicircular canals, making the canals gravity-sensitive. Could the same stimulus that caused vestibular injuries also elicited concussion symptoms? To quote from the results section, "Following exposure to vibration plus sustained acceleration (centrifugation), dizziness was reported by 5 of the 16 participants, headache by 2, lightheadedness/confusion by 2, fatigue by 4, minor back pain by 1, and illusory world motion by 3." With the clear exception of minor back pain, these are all symptoms of concussion.