I’ve noticed over on NOF that many people when talking about their DEXAs mistake the femoral neck reading for having something to do with their spines. It doesn’t. Not in the least. The femoral neck is part of your hip joint. It’s called a “neck” because it is rather graceful and tapered like a neck. It connects the femoral head, the large, round protuberance at the top of your thigh bone that inserts into the acetabulum (your hip socket) to the femoral shaft (the thigh bone.)
The density in the femoral neck is important because typically it is the most vulnerable area to fracture.
Why?
I wrote something about this before, loooooooong ago, when I first started blogging (although I’ve since learned that it may not be safe to use resistance bands or cable machines around the ankles — it puts too much stress on the hip bone)
Back to the topic at hand — why is the femoral neck so vulnerable? It has to do with the fact that as women, we are childbearers. Which means our hip girdle/pelvis area needs to be wider than a man’s. See the image below. (The lady pelvis is the top one.)
But women still walk around on two legs, just like men, and in order to be able to do that with that wonderful, swinging stride that human beings have perfected, our feet need to be under our torso. Which means the angle at which our femur inserts into our hip socket is a much sharper angle than it is for men. (They call it the Q angle. I don’t really know why they call it the Q angle — maybe because the quadriceps run along this bone?) See the image below.
That increased angle puts more pressure on the neck of the femur, making the femur neck most vulnerable to fracture. That’s why those spontaneous femur fractures are called “atypical” — because that’s not usually the part of a femur that breaks.
Anyway, when you look at your DEXA, the number that says Femoral Neck — it’s talking about that skinny strip of bone between your thigh and knobby end of your thigh bone, not your spine. They usually measure your left femoral neck, right femoral neck, then give you the mean femoral neck (the average of those two numbers together), and then do the same for the femoral shaft (the long part of the thigh bone.)
Hope that helps.
Thanks, Raye. That was the clearest explanation I’ve read anywhere.
It’s 12:09 a.m. here. Why am I still up working???
I don’t know. Why am I, for that matter?
When I first found out I had osteoporosis and saw my DEXA scan results, I am now embarrassed to admit that I somehow skipped over the word “femoral” and saw only “neck.” I had visions of my head bouncing away as my neck snapped! It was probably a couple weeks before I calmed down and read my results more carefully. Fortunately, I am much better informed now, thanks to bloggers like you and other research.
Made me laugh! It could be a new Washington Irving story: The Headless Osteoporotic.
hahah! I made the same mistake, and while I didn’t have visions of my head bouncing away, I did have visions of it sitting squarely atop my shoulders, with my neck somehow absorbed into my body! : )
Hey Raye, Take a look at this:
http://blog.melioguide.com/2011/is-your-neck-pain-caused-by-your-osteoporosis/
Do you think she “copied” my post from Sunday? Interesting that she wrote about it a couple of days after I did… But then it’s a common mistake.
I don’t know. I’d like to think it was coincidental.
You are probably right. I wandered around her site a lot yesterday. I like it.
By “common mistake,” I mean a lot of people get confused about what femoral neck means. I’ve lost track of the number of threads on Inspire where people have thought it meant something in their spines.
That’s what I figured you meant. I made the same mistake myself. Since the article was written by a physical therapist, I’m sure she has gotten the same question many times.
Hi Bone Architect – Richard at MelioGuide here.
The timing of our posting is purely coincidental. In fact it should have been up several months ago but I have fallen behind on our posts and this one slipped.
Margaret (at MelioGuide) gets this question all the time and the blog was written for her clients and the health professionals that she has trained to clarify the confusion.
Keep up the good work!
Hey, Richard:
I figured as much. Just from the sheer volume of posts on NOF/Inspire on any give week about femoral neck somehow being related to your spine, it seems like this would be a clarification that needs to be made over and over and over again. No offense meant. Just one of those weird coincidences.