[4] Wickham's original ambition was to practice in neurology and neurosurgery, but after working with Ralph Shackman at Hammersmith Hospital, he diverted his interest to renal medicine.

He ran the early Necker dialysis unit with Geoff Chisolm, following which he pursued his interest in urology under Alec Badenoch and Ian Todd.

He encouraged international networking amongst urologists and founded the European Intrarenal Surgical Society (EIRSS) in 1983 with Peter Alken of Mainz, and Joe Segura from the Mayo Clinic.

He was an early advocate for the use of percutaneous nephrolithotomy in the United Kingdom, insisting that National Health Service patients and urology trainees have access to the secured Dornier HM1 Lithotripsy machine in the private sector.

[2] Wickham was frequently frustrated at the slow rate of uptake of "minimally invasive surgery" by his colleagues and told The Times, "We still have far too many surgeons who believe that unless you cut a hole big enough to get your head in, you cannot see well enough to perform a proper operation".