Stamkos appeared at Lightning practice on Saturday wearing a yellow jersey, which usually indicates an injured player is cleared for some physical contact during practice.
Here's visual evidence.
Blackhawks 32-9-12 (@Arjun_AJB) January 25, 2014
Stamkos broke his right tibia in a scary collision in early November against the Boston Bruins. At the time, the thought was he would miss most of the regular season recovering. Instead, Stamkos was skating a month later and looks well on his way to making an Olympic appearance in a couple of weeks. He is not of this world.