According to The Wrestling Observer Newsletter, Randy Orton was injured on RAW during his match with The Big Show. Details are sketchy right now but the early word is Orton will not compete in the SmackDown Elimination Chamber match for the World Heavyweight Title.
As of now, it appears as though Orton will be replaced by Mark Henry, who is being brought back early from injury.
Take this for what it’s worth for the time being, as we await confirmation. We should have more soon.