...how would a "medicalizer" even work...?

Well, first the Medicalizer constricts the afflicted limb to the point of cutting off the blood supply. This works to stop bleeding wounds, specially if it’s not just a cut, and it’s more like, having half of your arm blown off for example. Then it would seem like it’s capable of closing bleeding wounds and accelerating the healing process- Making deep cuts into faded lines. However it’s not just the healing process it speeds up- We see it heal bones, broken bones, in a matter of seconds. It doesn’t leave any sort of scarring when the wounds are internal though. Given how we see most Troll technology to be Biotechnology? My bet is on viral nanomachines invading the limb and fixing it up.