Adam Rainer is the only person in recorded history to be both a dwarf and a giant. No, before you say it: we are not describing someone of average height.
Rainer was born in 1899, to parents of average height. By the time he reached his teenage years, it was clear that he was shorter than most in his town of Graz, in then Austria-Hungary. Denied entry to the army during World War One due to his own height - then 4 foot 6 inches - Rainer was unusually short for his age, and classified as having dwarfism, being shorter than the 4 foot 10 cutoff. A few years later he tried to get into the army again but still fell below the height requirement at 4 foot 8 at the age of 20.
Medical reports showed that Rainer had unusually large hands and feet for a man of his size, however, with his feet measuring at size US 10 (EU 43).
Then at 21 years old - long after the point where most people have stopped growing - Adam began a growth spurt that would eventually get him classified as a giant. By the time he was 32, he had grown to the height of 7 foot 2 inches. Previously too short to enter the army, he now towered over just about everybody he met.
In the early 1930s, Rainer was examined by Dr A. Mandl and Dr F. Windholz, who diagnosed him with acromegaly, a rare disorder where the body produces too much growth hormone. The disorder explained his abnormally large hands and feet - a common symptom - as well as his excessive tiredness and enlarged facial features.
The medical team determined the cause of his sudden growth spurt, a tumor pressing against his pituitary gland. The doctors operated on Rainer to remove the tumor in the hope of preventing further growth. Though successfully removed, it was only enough to slow Adam's growth. When he was measured the next year his height was unchanged, but his spine had begun to curve, meaning he was still growing.
As he grew, his health declined, with his curved spine eventually leaving him unable to stand on his own. His eyesight and hearing grew worse, and he eventually died aged 51 in a "home of the aged", measuring 7 feet 8 inches tall (2.34 m), the tallest man in Austria.
There are currently no other known instances of a person being classified as both a dwarf and a giant across their lifetime.