What causes a vertebral bone to not form?

I have a question for you guys. Back when I was fourteen, I had spinal surgery, and an X-ray confirmed that one of my Thoracic vertebrae is just not there. Nobody's ever had an explanation for why that is. Anyone else have something similar happen to them? Anyone know if there's a name for the condition?

 

Genetic defect to the best of my knowledge, or you simply had bad posture for too long and the friction wore it down. Yeah, they might not have picked up the minute bone particles. Did you have bad posture?

 

Almost certainly you were born without it. It's not as uncommon as you may think. I'm missing a ligament in one ankle that never formed. What causes it? Genetics. Environment. Something your mother did/didn't do.

At the end of the day, it's that important a question for you to answer, primarily because you're not in a position to answer it. Unless you've been hiding an MD and a PhD from us.

 

The full explanation is probably almost entirely genetic, and will likely never be known. I've often been heard saying that I'm surprised anything manages to be born at all given the sheer scale of such a project and the number of possibilities of fatal failure that present themselves. Flip through a developmental biology textbook sometime and prepare to be awestruck. There is also still plenty variation between human beings. Of course everyone is well aware of that when it comes to thinks like height and eye colour, but often the picture we're presented about the rest anatomy is static, "This is what everyone looks like on the inside." Sadly (at least from an educational standpoint), this just isn't the case. Some people have fewer vertebrae, some have more. The same goes for ribs and teeth. Sometimes people are born with tails (though this is just a special case where the extra vertebrae are plainly visible). As you're well aware, consciousness doesn't always line up with the sex of the body it finds itself in. It's all the same thing really, the vagaries of development.

 

It's most likely a genetic anomaly, although there's a good chance that when that bone was supposed to form, something environmental interrupted the message that told it to form, causing the event to just not happen. It's quite likely a neural tube defect of some sort, which are usually caused by inadequate folic acid in the pregnant woman's diet. You are lucky that you didn't get just part of a vertebra and end up with spina bifida, though.

 

As far as posture goes, I did have Scheuermann's Disease growing up, which is why I had the back surgery to begin with. But my brother had it too and all his bones were fully developed. I guess it's just one of those things.