It came in a game against the San Diego Chargers in December 2009, a head-first collision that's had the long-term effect of occasional neck stingers.
Ware -- a six-time Pro Bowl linebacker -- explained Wednesday that he sometimes gets a tingling sensation followed by numbness down his arm that will last a couple of seconds.
"Then I'll have all my strength, and it's like all right, wait a little while, and go back out there and keep playing," Ware said, according to The Associated Press. "But sometimes that can take away from maybe one play or a big play you can make, or two plays in the game where it's key situation when you know you're wanting to be out there and playing."
Ware missed a workout last week because of a strained neck. He underwent X-rays and other tests that he labeled as precautionary.
"It's just going to be that way, you've just got to find some way to work through it and just do precautionary stuff," he said. "At the end of (last season), it flared up a little bit, and sometimes I would come out of the game, get little stingers here and there, but you've just got to work through it."
Ware has yet to miss a game for the Cowboys in seven seasons. Any time you have neck issue it's obviously a cause for concern, but Ware sounds confident he has the situation under control.