Carl Nicoladoni (April 23, 1847 – December 4, 1902) was an Austrian surgeon who was born in Vienna. He received his medical doctorate from the University of Vienna, and was later a professor of surgery at the Universities of Innsbruck (from 1881) and Graz (from 1895).
Nicoladoni specialized in orthopedic and reconstructive surgery. He was particularly interested in research and diagnosis of scoliosis and published several treatises on the disorder. He also performed the first successful thumb replacement. This operation involved replacing a boy's lost thumb from the second toe of his right foot.
Nicoladoni made several contributions in regards to urogenital and gastrointestinal surgery. He introduced new surgical techniques concerning esophageal diverticulum and torsion of the spermatic cord. He also investigated the possibilities of gastroenterostomic surgery.