Born in 1899 in Graz, Austria, to parents of average height, Rainer only gained a modest 4’8” of body length until he was around 19, according to Business Insider. But by the time he was 21, Rainder started to experience a growth spurt that left him towering at a 7’ 1” inch frame by the time he turned 31.
Perplexed by this anomaly, doctors launched an extensive research into the case and determined Rainer had a tumor on his pituitary gland that was causing an overproduction of growth hormones. The tumor was removed to cure the uncontrollable growth, but it only slowed the pace instead of stopping it completely. He continued to grow for the remainder of his life.
Sadly, because of this unnatural height, Rainer developed numerous health problems including a severe curvature of the spine that eventually left him bedridden. He also lost sight in his right eye and the ability to listen in his left ear.