Blame it on your ancestors as this condition only occurs in two-legged humans and does not affect our great ape cousins.The back pain condition has long been assumed to be the result of increased stress placed on our spine by our unique ability to walk upright on two legs.
The researchers used advanced 3D shape analysis techniques to compare the final lumbar vertebrae of humans with and without spondylolysis to the same bones in our closest living relatives, the great apes. The team found that the differences between human vertebrae with spondylolysis and great ape vertebrae were greater than those between healthy human vertebrae and great ape vertebrae.
people who developed spondylolysis have vertebrae that are more wedge-shaped, where the front is taller than the back, in addition to other subtle shape differences. For decades, scholars have assumed that the reason humans are so commonly afflicted with back problems is because we walk on two legs.