[2] Sinnathuray was appointed Professor and Head of the Department of Obstetrics and Gynaecology at Faculty of Medicine, University of Malaya in 1970 and remained in office till 1986.
[3] Sinnathuray headed a team of twelve specialists who successfully performed the first intrauterine transfusion in Southeast Asia in early 1970.
He was a prolific researcher with over 60 scientific publications in indexed medical journals in an era that predated the internet or evidence-based medicine.
His elder brother is retired Singapore judge T. S. Sinnathuray, who was born on 22 September 1930 and died on 18 January 2016 after attaining the age of 85.
Sinnathuray was knighted by the 5th Yang di-Pertua (Governor) of Penang, His Excellency Tun Awang Hassan (himself an eminent first generation obstetrician) when he was conferred the Darjah Setia Pangkuan Negeri (DSPN) in 1985.