 Larynx transplants are a rare procedure.The world's first successful operation took place in 1998 at the Cleveland Clinic, and the second took place in October 2010 at the University of California Davis Medical Center in Sacramento.Pioneering work on the structure and evolution of the larynx was carried out in the 1920s by the British comparative anatomist Victor Negus, culminating in his monumental work "The Mechanism of the Larynx" (1929).