Mr Hamlyn has worked as a Consultant Neurological Spinal Surgeon for over 20 years. During this time he has lead several neurosurgical teams in some of London's elite teaching hospitals such as St Bartholomew’s Hospital and The Royal London Hospital. He has been an Honorary Consultant Neurosurgeon at University College London Hospital since 2009.
His clinical activity consists currently of some 3,500 outpatient consultations and just over 300 operations per year. The majority of his work involves minimally invasive keyhole and restorative, reconstructive surgery. He has substantial exposure to elite level sports from Premiere League football and rugby, nation team members in several different sports, UK sponsored athletes, jockeys and even The Royal Ballet. Mr Hamlyn was a member on the 2012 Olympic Bid Advisory Panel and has worked as a correspondent for the sports section of The Daily Telegraph newspaper.
In 1996, he was awarded Fellowship of The Institute of Sport Medicine for his work in the field of head injury in sport. He has worked as medical advisor to the Society of British Neurological Surgeons (first Safe Neurosurgery working group), General Medical Council, Trigeminal Neuralgia Association of Great Britain, British Olympic Association, British Boxing Board of Control, The Jockey Club of Great Britain, UK Sport, The Royal Ballet, GB rowing team, and England Rugby, plus numerous premier league football and rugby clubs.
Mr Hamlyn was a Founder and President of The Brain and Spine Foundation. He is also Director of Education for The Institute of Sport Exercise and Health.