2010: 172 NFL concussions from training camp through the playoffs.–The Concussion Blog, December 2013, Dustin Fink.
NFL Concussion Totals by Season: 2011: 252. 2012: 261. 2013: 228. These figures were released by Jeff Miller, the NFL’s senior VP of health and safety policy, at the Super Bowl.—“NFL: 13 percent fewer concussions in ’13 than ’12”, NBC29.com 1/30/14, from AP.
One-third of all concussions were left off the NFL injury report for the 2012 and 2013 seasons (the figures in the above item include most of those). Teams don’t release injury reports until Week 1 of the regular season, meaning most concussions from training camp are left off the list. Also, teams don’t release injury reports after bye weeks or after their final games, both regular season or playoffs. During the above 2 seasons, players returned to play almost half the time without missing a game, despite guidelines endorsed by the NFL Players Association from the American Academy of Neurology stating that athletes are at greatest risk of repeat injuries in the first 10 days post-concussion (the vast majority of games are played weekly). The second half of both seasons accounted for 38 more concussions than the first half. Dustin Fink, a certified athletic trainer who tracks head injuries on “The Concussion Blog”, says the increase can be explained by the repetitive nature of smaller, subconcussive hits. “The theory is that the more of those you sustain, eventually you’re going to lower your threshold for having a concussion.” Cornerbacks and wide receivers sustained the most concussions over these 2 seasons, followed by safeties, tight ends, and running backs and linebackers.—“What We’ve Learned From Two Years of Tracking NFL Concussions”, Frontline on pbs.org 2/4/14, Jason M. Breslow.
A 2005 study by the Center for the Study of Retired Athletes, based at UNC, of 2500 former NFL players, found that cognitive impairment, Alzheimer’s-like symptoms and depression rose in direct proportion to the number of concussions a player had sustained.—NY Times.
Players who have suffered 3 or more concussions have a 5-fold risk for mild cognitive impairment and a 3-fold risk for permanent concussion.—Kevin Guskiewicz, UNC research director.
At the National Institute of Health, researchers have been successful treating concussed mice by passing an antioxidant called glutathione through their skulls immediately after a concussion, reducing brain tissue damage by nearly 70%. MRIs have shown that concussed humans similarly leak from blood vessels lining the skull, which seep down and damage brain tissue, as happens in mice.—“Concussions”, SI The MMQB 4/28/14, Robert Klemko.
UCLA researchers believe they have identified tau in 5 living former NFL players, though they could not definitely determine the protein was tau. The players were between the ages of 45 and 73, and had histories of mood and cognitive problems. Brain scans showed a chemical marker that fastens to tangles of tau gathering in the amygdala and subcortical regions, the same areas where scientists have found tau during autopsies of patients who had CTE. Researchers also found that a higher number of concussions correlated with a greater amount of chemical marker attachment, suggesting more buildup of the protein. Scientists are still trying to determine how the presence of tau may trigger the development of CTE. They are looking at the role of genetics in CTE, since many athletes and military veterans take repeated blows to the head and do not develop the condition. One of the players studied, a former quarterback, appeared to have tau in his brain but showed only signs of aging and not CTE.—“Study finds clue to brain disorder—before death”, SF Chronicle 2013, Drew Joseph.