See also:
Do you have (an) extra rib(s)?
Sixth lumbar vertebrae in your spine are uncommon, but far from extraordinary. About 10% of the population has an extra bone in this region, and while additional vertebrae don’t typically affect your health, they can complicate treatment for spinal cord injuries.
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Yes, I have an extra vertebrae, L6.
I’m O- and curious if others have this trait.
Yes, an extra vertebrae & also O negative