Roman doctors learned a lot about the human body as they tended gladiators wounded in the amphitheatres. However, dissection of humans was forbidden in the Roman Empire, so Roman anatomists such as Galen had to rely mainly on dissections of animals to further their knowledge. Galen recommended dissecting monkeys that walked on two legs, like men.
Galen did manage to work a little with the human body, and described how he had human corpses to dissect when he found a hanged criminal, and when a flood washed some bodies out of a cemetery. Despite this, he made various errors in his analyses of how bodies work.
Galen's books show a good knowledge of bone structure. He also studied the lungs, the muscles, the heart and blood and the nervous system. He conducted experiments on pigs, and when he cut the spinal cord in different places he realised how the nervous system takes messages from the brain to the muscles. As he mainly relied on dissecting pigs and monkeys, Galen also made mistakes in his anatomical discoveries.
Galen based most of his information about anatomy on what he saw when he dissected the bodies of animals. This led him to make mistakes. Some of his errors were:
Galen accepted the Greek theory of the four humours as the cause of disease. However, the Romans did not continue the Greeks' investigations into disease and rejected Greek ideas, so Roman knowledge of disease did not progress.
Roman ideas about disease were muddled. For example:
All these ideas survived until the 19th century.
Through their work with gladiators and wounded soldiers, Roman doctors became experts at practical first aid and external surgery.
They could do a large number of simple external operations, such as removing polyps up the nose and goitres from the neck.
We know that the Romans developed new surgical and midwifery instruments - though they look barbaric to us nowadays. They also developed the Caesarean section to remove a baby from the womb (although it is not true that Julius Caesar was born this way). In those times the mother always died - Roman Caesarean sections were usually performed to save the baby of a woman who had died during childbirth.
We have no evidence that Roman surgeons successfully operated inside the body. Roman doctors did not have anaesthetics, and had only herbal antiseptics - so successful surgical operations would have been extremely difficult for them to perform.