Yes, they are correct and meaningful. They all mean the same thing.
Generally, when I hear 'his arm was bruised too', I think that it has been said that something else was bruised. In these cases, nothing but the arm was bruised.
I don't believe "too" is ever quite as restrictive as you interpret.
In your examples, he had an injury (the broken leg) and another form of injury too (the bruised arm) so they are both forms of injury, even if different types of injury.
Making up an example.
Friend 1: He ordered all the most expensive desserts on the menu.
Friend 2: And he arrived in a stretched limousine too.
Even though one friend talks about a man buying food and the other about travelling in a car, which are quite different activities (except at drive through restaurants), both those statements are about "things that cost a lot of money" so it makes sense to use "too".
I watched a movie with her--and I played on her X-box too.
Both are recreational activities, but they are not identical recreational activities, yet the sentence is failrly well-formed even with "too" in it (although it might be better to use both either "and" or "too", only one is needed, not both).