Born on 3 November 1921 the son of A C McMillan of Huddersfield, he was educated at Leeds Medical School, qualifying in 1945. He served as demonstrator of pathology in the School and as house surgeon at the General Infirmary. Deciding to specialise in orthopaedics he took the Fellowship in 1952, was orthopaedic registrar at the Royal Victoria Infirmary, Newcastle-on-Tyne, and then senior orthopaedic registrar at the Royal Infirmaries at Sheffield and Edinburgh. He was appointed orthopaedic surgeon to Croydon General Hospital in 1961. McMillan owed his achievement to hard work and determination, but he was a cheerful, kindly and humorous man. He married and had a family, but the marriage proved unsuccessful. He died from an overdose of barbiturates on 25 September 1963 aged 41, survived by his parents. He was buried at Bandon Hill Cemetry, Wallington, Surrey.