Following advice from his mentor
Otto Goetze in
Erlangen, Stelzner joined the surgical faculty at the
University of Hamburg in 1955. He received a scholarship from the
British Council to complete additional training in colorectal surgery at London's
St Mark's Hospital. The collaboration with leading colorectal surgeons in
Britain left a strong impression on Stelzner and strengthened his desire to specialize in this field. For this monograph, Stelzner was awarded the Langenbeck prize, the highest scientific award of the German Society for Surgery in 1960. In collaboration with the anatomist Jochen Staubesand, Stelzner investigated the exact structure of the hemorrhoidal vessels. He demonstrated that
hemorrhoids are not enlarged venous structures, but rather arteriovenous cushions for which he coined the term
corpus cavernosum recti. These cushions have great importance for the anal continence. Stelzner also developed the concept of anorectal continence organ. He pointed out that this organ shows significant differences in males and females. This has bearing on the details and the outcome of anorectal surgical procedures. Further studies revealed the spiral structure of the esophageal wall muscles. Stelzner worked with the anatomist
Werner Lierse in these studies and made use of translucent muscular preparations and serial sections of esophagi, which were processed in situ. Knowledge of the exact structure of the muscular wall of the esophagus forms the basis of surgical procedures for treatment of
achalasia and
gastroesophageal reflux disease. ==1967–1987: Professor and Chairman of Surgery==