Final answer:
A penalized injured skater who returns to play before their penalty expires while a substitute is still on the penalty bench results in a 'bench minor' penalty for too many men on the ice, which is a two-minute minor penalty.
Step-by-step explanation:
If a penalized skater is injured and unable to take their proper place on the penalty bench, and a substitute is placed on the bench, there are specific rules that govern this situation. In hockey, according to the National Hockey League (NHL) rulebook, if an injured player who has been penalized returns to the ice before their penalty has expired and the substitute is still in the penalty box, the team commits a 'bench minor' penalty for too many men on the ice. The injured player who returns early or the substitute must serve a two-minute minor penalty. However, in different leagues or levels of play, such as amateur or international, the rules may vary slightly so the specific rulebook of that league or tournament should be consulted.