War helped surgery improve in the medieval and renaissance periods:
In the medieval period, John Arderne set up the Guild of Surgeons, this meant surgeons had to have a year of training.
In the renaissance period, Pare developed turpentine ointment and ligatures to stop blood loss
Understanding of anatomy + surgery improve over time because of books and communication of knowledge
John Arderne in the medieval period writes a textbook called ' The practice of surgery "
Vesalius in the Renaissance periods writes the book " fabric of the human body that included anatomical drawings, which unlike Arderne, Vesalius' book was able to be mass produced fast via the printing press