The crazy truth is that we didn't have much actual medical knowledge until the last 100 years or so. People who are sick (and their doctors) were desperate enough to try anything, so there have been some pretty insane medical procedures tried over the years. Still, that's not much excuse for some of these strange practices!
I bet you thought the saying about blowing smoke up someone's butt was totally random. Nope, it sadly comes from an actual "medical" procedure that was popular in the 18th century. It began as a misguided way for Native Americans to attempt to resuscitate the dead. It was then was adopted by colonial Americans and Europeans as a basic cure all for everything from hernias to arthritis. It was even used on finicky horses!