Are surgical experiments on human subjects necessary?

This paper does not contain anything new, it only analyzes the scientific value of surgical experiments done on human beings versus animal experiments. In my opinion the simple fact that in animal experiments we start from a well defined healthy specimen results in more reliable experiments than those done on patients; furthermore, in experiments on patients we have simultaneously to take into account two different goals: 1. to cure the patient; 2. to acquire the scientific data. This double aim may present a handicap. As an example I tried to illustrate why animal experiments are of great importance in the case of otosclerosis surgery.