An autopsy on the body of an ancient Scythian cavalier found in the Altai Mountains shows he had a degenerative bone disease for several years before he died, German scientists said Friday. The 2006 find of the preserved body and the man's rich possessions on the Mongolian side of the mountains was a scientific sensation. The Scythians were a nation of horsemen in central Asia.

The man, who died about 2,300 years ago at the age of 50 or 60, would have been incapable of any demanding physical work for several years before his death, Michael Schultz, a palaeopathologist or scientist who studies diseases in ancient remains.

Schultz said the cause of the "bone-decaying process" was unclear and an explanation would not be suggested until the end of this year.

The 1.67-metre man would have belonged to the upper middle class of his society. The condition of his teeth showed he mainly ate meat.

"The teeth were barely worn. That's typical for nomads," said Schultz. The man's upper body was poorly preserved, only allowing the team of scientists to study a few ribs and vertebrae.

The study established the man had serious arthritis in the hands and hips and had chronic inflammation of the sinuses. At some point in his life, he had also broken his arm in a fall and suffered a middle-ear infection.

The remains of two horses, a fur coat and weapons were among the possessions which were found in the mound and are under conservation treatment in Novosibirsk, Russia, said Hermann Parzinger, the lead archaeologist on the excavation.

The burial chamber inside the manmade mound had very dry air, thanks to a lump of permanent ice beneath a wooden "floor". Parzinger said the remains had been more or less "freeze-dried" because of this.

The mummy, which was brought to Goettingen, northern Germany in December 2006, will be shipped to Ulan-Bator, Mongolia next month.