The NFL will review its concussion protocol this offseason.

Case Keenum was not removed from a game this past season despite clearly being disoriented after being knocked to the ground.

After the game, Keenum was found to have sustained a concussion, and he did not play in the next two games.

Jeff Miller, the N.F.L.’s senior vice president of health and safety policy, said that Keenum should have been removed from the game to see if he had a concussion.

“This demonstrated an area where there were definitely not best practices,” he said.

Miller also said that the number of documented concussions increased by 31.6 percent, 271 in 2015 compared to 206 in 2014, partly because the number of players who were screened for concussions doubled. He also said that more players are self-reporting concussions.

“That’s a positive trend in terms of the culture change,” he said.