Note that not all "way back then" physicians necessarily agreed with each other. For example, some physicians completely dismissed the "doctrine of signatures" (liver-shaped leaves were good for liver ailments, and God did that so we could know what to use) as quackery.
On the other hand, we do have a lovely account of Ferengi (Crusader) "medicine" from the point of view of a Christian subject of one of the Sultans. In short, during one of the more peaceful periods he was sent over to care for a Ferengi leader who had sustained an injury. He went over and cleaned and dressed the leg wound and recorded that it was healing nicely. While there, he also had begun treating a woman for headaches.
Then a learned churchman and physician arrived and dismissed all that infidel nonsense that this mere Greek heretic was foisting off onto good Latin Christians. First, he decreed that the woman's brain was in need of cooling to cure the headache. She was held fast, her skull was neatly opened and the brain removed to be washed in wine. It was then returned to her skull but somehow she did not revive.
Then, the leg injury was "treated". A large man with an axe was called, since the wound had not been properly cauterized with a hot iron or had boiling pitch poured into it. A good swat, and the leg was hacked off. The victim immediately expired from shock.
The local physician made a hasty retreat.
