Board Thread:Boruto Discussions/@comment-1458758-20171229124917/@comment-1458758-20171231160016

Gagua2028 wrote: Katasuke was a doctor back then? I thought he was a scientist from the start.

Just to add to what Killman said, during the Ao chapter, he says he owes his survival to Katasuke and that it was a miracle he survived at all, which would imply to me that he was a medic during the war. Since we know he also possesses at least some ninja skills, it seems likely he was a mednin sent in as first response to the HQ and managed to save Ao then, and later came to him with the prostetics like he did for Chamaru.

If I were to guess, his role as a mednin would have been akin to medical researcher, like Jonas Salk, but with ninja stuff.

That's all purely speculation on my part, but I think it's as good a thoery as any right now until we get more data on the topic.