Minor injuries and illness for the most part, that wear more seriously on him because of his shitty general health. His diet is terrible and he doesn't rest nearly enough and he always waits way too long to come in (ie, when someone makes him go.) He's probably a pretty frustrating patient, but in recent months as he's stepped into a more important role keeping Project Jump safe, he has been making more of an effort to take more responsibility for his health, and been more realistic about the help he does need. For example, he's probably been interested lately in obtaining a prescription for medication to control some of his more debilitating OCD symptoms, rather than self-medicating or attempting to ignore them.