The injury episodes are ones where the injury is an ongoing part of the storyline rather than just something that happens along the way.
I've just added Trial of Tears to that list because it plays a relevant part in the subplot of the episode.
In the Stringer, the injury happened quite late in the story and had no impact on the plot of the episode. In fact, it wasn't even the same injury he started with!
All of the episodes on your list have MacGyver with other people and the majority of them are people he's never met before.