The former Detroit Lions defensive lineman, who was named to four Pro Bowls during a 12-year NFL career that ended in 1970, joined 69 other ex-players in a suit filed in U.S. District Court Thursday, CNN reported. It's the 12th such suit brought against the league involving about 700 players, the network said.
The ex-players allege the NFL not only didn't do enough to warn them they risked permanent brain damage if they played too soon after a concussion, but that it concealed evidence about the risks for years.
The plaintiffs say they have neurological problems resulting from traumatic impacts to the head.
"Alex suffers from dementia but still enjoys many things, including watching football," his wife Susan Clark said in a news release. "But dementia prevents him from doing everyday activities such as driving, cooking, sports fishing, reading books and going to big events or traveling.
"His constant complaint is dizziness -- the result of multiple concussions. What Alex wants is for the game of football to be made safer and allow players and their families to enjoy a healthier, happier retirement."
Karras, 76, who now lives in California, went on to an acting career that included a memorable role as the horse-punching character Mongo in the movie "Blazing Saddles" and a starring role in the TV sitcom "Webster."