Surgery is perhaps the oldest form of medicine. The practice of making holes in the skull, or trephining, is prehistoric, while one of the most important early Egyptian papyruses, the Edwin Smith Papyrus of about 1700 bce, is a list of surgical techniques.
When young Galen learned his surgery in Pergamum around 150 ce, he acquired many of the skills that had been taught since the time of Hippocrates; These are still employed by surgeons today. He learned to set fractures and replace dislocations, to stitch or strap torn muscles or skin (tying off blood vessels along the way), and to cut or tie off hernias. The common invasive techniques included removal of growths of all kinds and of stones from the easily accessible bladder, trephining to relieve pressure (still used), and drainage of fluid that had collected in various body cavities.
After Galen moved to Rome in 162, he dissected many animals and developed a clever (but mistaken in important details) theory of how the body functions -- advancing knowledge much more than practice. In the 150 years after Galen's death, his reputation quietly grew; by the fourth century, he was the recognized authority for all medicine in the West and soon in the Arab world as well. While Galen's view of medicine prevailed, the slow, anonymous growth of surgical practice continued. By the seventh century, for example, surgeons had learned to perform tracheotomies when needed and to handle aneurysms if they were located in accessible places.
Arab doctors advanced medical standards of treatment, including roles for immunization, anesthesia (hashish), diet, and cleanliness, but they failed to go beyond a limited understanding of Galen in surgery, largely because Islamic practice was against deliberate bloodshed (except in war or as punishment). The Arabs separated surgery from medical practice, a division that passed over to the West. Surgeons were the lower class of practitioners, while physicians, whose closest approach to surgery was to let blood, were the elite. For a time the barbers who cut hair and beards were also the surgeons who cut skin and organs. These barber-surgeons of the West were hampered by a lack of anesthetic beyond strong drink (although some knew of opium-based concoctions that were better) and a belief that pus was good for healing. Speed was essential because of the patient's pain, and the most successful procedures were the most external, such as lancing boils or removing cataracts. Amputation of limbs was frequently needed because of the lack of cleanliness in treating minor wounds, leading surgeons to develop considerable skill at the process. Cauterization -- sealing off blood vessels by searing flesh -- was found to be easier and thus was more commonly practiced than use of ligatures to tie off arteries and veins.
In the East, the surgical traditions were not much different from those in the West. In India, surgeons performed much the same kind of operations that Galen learned and at about the same time. In China, despite advanced ideas on circulation of the blood and use of biological substances (some from animals as well as the better recognized herbal medicines), acupuncture was more emphasized than invasive surgery.
About 1275 surgery in the West began a slow improvement. The scalpel, which had been replaced by ordinary knives, was revived. In 1543 the great work of Vesalius corrected many misunderstandings about human anatomy, with excellent and accurate illustrations. Still, it was not until the 18th century that the barber-surgeons in France and England were completely replaced by medical surgeons. Shortly before that time Ambrose Paré introduced boiling oil to control infection in wounds, which surprisingly was a great improvement over previous practices. The widespread use of firearms probably contributed to increased knowledge on how to remove segments of gangrenous intestine.
Despite cycles of refinement of technique, there was little overall improvement in surgical practice from Antiquity until the introduction of good anesthetics in the mid-19th century. When surgeons could work deliberately on completely anesthetized patients, modern practice truly began.
