From a previous thread:
Nebraska Linebacker Granted Medical Redshirt
LINCOLN (AP) - Nebraska middle linebacker Corey McKeon was granted a medical redshirt by the NCAA Monday, after not participating in the majority of Nebraska's 2007 games. As a result of the ruling, McKeon has been granted one extra year of eligibility, meaning he will be able to return to the field for the 2008 season.
Under NCAA regulations, a player may be granted a medical hardship waiver if he or she does not participate in more than 20 percent of the team's games, with all participation occuring during the first half of the season.
Nebraska athletic department officials reviewed game film and determined that McKeon did not actually participate in any of Nebraska's final ten games of the 2007 season,
"Participate is defined as 'taking part in something,'" explained Nebraska Director Of Football Operations Jeff Jamrog. "We contended, and the NCAA agreed, that Corey didn't really take part in the final ten games."
NCAA Vice President Gary McIntosh declined to comment, other than saying "That game film speaks for itself."