If an abnormality in your body doesn't cause any problems, why spend time diagnosing it? Or even researching it? My brother had to have a back x-ray for a problem and his doctor told him that he had butterfly vertebrae but that's not causing the pain. So?

Butterfly vertebrae are vertebrae (bone that make up your spine) that have a cleft, an indentation or opening, through the middle. If you look at it with an x-ray, the shape reminds you of a butterfly. Usually, this doesn't cause any problems and goes undetected unless there is a reason to x-ray that part of the back. Sometimes, however, there may be pain, but not from the abnormality itself.

The fact that your brother has butterfly vertebrae is important to know because although the abnormality itself doesn't cause harm or pain, if enough of the vertebrae sticks out, it can knock the alignment of the spine out of whack. This won't cause pain right away, but as your back works to adjust for the misalignment, it can cause back pain. For example, you could have butterfly vertebrae in the lower part of your back, but you may have pain in the mid to upper part as a result.