MB BChir Camb 1950, MA 1951; FRCS Eng 1957.
Lythgoe was born in Wilmslow on 10 November 1926, the son of Sir James Lythgoe, CBE, chairman of Manchester Regional Hospital Board. Lythgoe studied medicine at St John's College Cambridge and MRI and was house surgeon at MRI before serving in the RAF. Lythgoe held resident appointments at Stockport Infirmary, MRI, Christie Hospital Manchester and Ancoats Hospital Manchester. He was a research fellow at Massachusetts General Hospital in 1960 and on his return to England was appointed senior registrar to Withington Hospital Manchester. In 1964 Lythgoe was appointed consultant surgeon to Preston Royal Infirmary and Chorley and District Hospital. He was a fellow of the Association of Surgeons.