The death of renowned jockey Walter Swinburn has been ruled accidental by a London coroner.

The 55-year-old suffered a fatal head injury after falling approximately 12 feet from his bathroom window in Belgravia, central London, on December 12 last year.

An inquest at Westminster Coroner's Court heard that although Swinburn had epilepsy, it was not possible to establish whether this had contributed to the fall and coroner Dr Shirley Radcliffe found he had died as the result of an accident.

"She confirmed that he had fallen from his bathroom window. The drop was estimated at about 12 feet, and it was into a courtyard," a coroner's officer said.

"It was confirmed that Mr Swinburn suffered from epilepsy, but whether or not he had an epileptic fit which caused him to fall, was not possible to determine."

Nicknamed the 'Choirboy', Swinburn rode trhe great Shergar to a breathtaking success in the 1981 Derby at the age of 19, one of three winners for him in the Epsom Classic alongside Shahrastani (1986) and Lammtarra (1995).

Swinburn will always be remembered for his partnership with the Sir Michael Stoute-trained Shergar, but the Shergar story went on to run much deeper than that, with the horse kidnapped from Ballymany Stud in Ireland on the night of February 8, 1983.

It is generally accepted the IRA were the culprits, that his abductors were ill-equipped to control a thoroughbred stallion, and that he was killed shortly afterwards. But his remains have never been found.

Swinburn picked up many other big-race successes around the world before his retirement in 2000.

He then took over the training licence from his father-in-law, Peter Harris, in November 2004, sending out over 260 winners from his Hertfordshire base before handing in his licence at the end of October 2011, citing financial reasons.