In 1910 he succeeded Paul von Bruns (1846–1916) as head of the surgical clinic at Tübingen.
Perthes' primary area of research involved radiological treatment and therapy.
Perthes took the first X-rays of a patient with this syndrome in 1898; however, his findings weren't published until several years later.
While in Qingdao, he had the opportunity to perform radiological studies on the feet of Chinese women that had been subjected to the traditional practice of being crushed and bound.
As a surgeon Perthes made several contributions, including a procedure of suction drainage for empyema, and the use of a pneumatic cuff for hemostasis during limb surgeries.