In 1848 he earned his medical doctorate from the University of Giessen, and from 1848 to 1861 served as a military physician with a Hessian troop outfit. During this time he also worked at a small hospital in Darmstadt that he co-founded. In 1861 at the request of Carl Friedrich Strempel (1800–1872), he was appointed professor at the University of Rostock and director of the surgical clinic. In 1867 he succeeded Karl Otto Weber (1827–1867) at the University of Heidelberg. During the Franco-Prussian War he served as a physician in reserve hospitals. Simon was a member of the Corps Starkenburgia Giessen (1843) and Saxo-Borussia Heidelberg (1845).
Simon specialized in the fields of gynecology, orthopedics and military surgery, and published a book involving his early experiences with gunshot wounds. In 1851-52 while in Paris, he had the chance to observe Antoine Joseph Jobert de Lamballe’s operative treatment of vesicovaginal fistulae (VVF). Impressed by Jobert's success rate with VVF, Simon developed his own surgical technique for VVF when he returned to Darmstadt.
Simon demonstrated that the excretion process remains functional in animals with one healthy kidney, and on 2 August 1869 performed the first planned nephrectomy on a human, only eight years after the first nephrectomy by Erastus Bradley Wolcott.[1]
