So I have this character I need to injure a bit to slow him down and limit his actions. He's a human male from the US, approximately forty-one years, and in pretty good shape, as he's a military officer who spends a lot of time in the field. I need a reason for him to be willing to team up with someone he wouldn't normally trust, and being somewhat injured seemed like an obvious reason.
I really want it to be a chest injury of some sort because of reasons in the setting, but I'm open for other suggestions, too.
He needs to be able fire a gun (actually a energy weapon, but with a similar recoil and handling as a small firearm) and move around, though he doesn't need to do more than that. At first I thought about cracked ribs, but from what I've found, that'd make it hard to even breathe, so I'm not sure how well he could fight through that. He is a very stubborn man with high pain tolerance, if that matters any, and adrenaline is probably involved. He also doesn't have much of a choice.
Bruised ribs might work, too, but I've got problems finding any info on how bruised ribs feel as opposed to broken ones. Would it be easier to fight with?
Is there any other chest injuries that could severely limit a person without knocking them out or killing them? He got injured in hand-to-hand combat with a fellow soldier (an US Marine if it matters), so it has to be one that could be caused without weapons.
He could probably take some pain medication, if that would help, but that's the limit of the medical treatment he has access to at the moment.
I've tried searching for various iterations of "fighting with chest injuries/broken ribs/bruised ribs" but all I can find is martial arts sides talking about how long after an injury they can train/fight again, which isn't helpful here, and general searches for chest/rib injuries just give me symptoms and healing time. Any tips for better search terms is accepted with thanks.
I'm not really concerned with after-effects of fighting with an injury, as this is sci-fi and he'll eventually have access to alien healing tech, but for the duration of the fight, he needs to be limited in his actions.