Simon was appointed to Leeds Teaching Hospitals as a Consultant Trauma and Orthopaedic Surgeon in 2002, having completed surgical training in Bath and Bristol and following fellowship training in the Ilizarov method at the Ilizarov Scientific Centre in Kurgan, Siberia. He was formerly an officer in the Royal Army Medical Corps, serving with the Brigade of Gurkhas in Dharan, Nepal. As a House Surgeon at RAF Wroughton he was involved in the surgical care of servicemen evacuated from the First Gulf War. His practice includes the treatment of severe lower limb fractures and post-traumatic limb reconstruction including non-union, mal-union and deformity, limb length inequality, bone loss, bone infection and amputation. He is currently elected secretary of the British Limb Reconstruction Society. In May 2018 he was awarded the degree of Master of Laws with Distinction in medical law and ethics by De Montfort University Leicester.