Friday, October 16, 2009

Morphometrics Part I


Hmmm, what is that?

Well, it seems to be a field of study where angles, lengths, relationships, patterns of organisms are recorded and compared, then used in various scientific data recording. It can serve a variety of purposes.

In medicine, at times, it is used for diagnosis. Where I have been going for treatment in New York, morphometrics is used for just this reason.

I have the print out of these measurements, taken from viewing various CT scans I had done in New York.

There is a section for data titled "Cranio-Cervical Junction." Those not into medicalese can probably figure out that this is right where my problems lie: cranio: skull....cervical is the upper part of the spine. With my Jefferson Fracture of the C1 and "dislocation of the occipital condyles"....this is exactly the area that causes my ongoing problems (except for the pain and weakness in my lower extremities and lower back, which results either from anamolies at my "CCJ" or my tethered cord surgery area (L4, L5, L6, or both).

On this sheet, I see a measurement listed as the "Basion-Dens Interval." I know what this is, but can I explain it? The Dens is the finger-like bone that sticks upward as part of the C2 (axis) vertebra. The C1 (atlas) is a ring which sits over the C2 and together they articulate so that the head and neck can turn in many, many different positions. In fact, this articulation and action is the most varied joint in the body. Just think of how much you can move your head and turn it in so many different positions! (not me, but hopefully, you can! ha!)

Okay, that was the "dens." Now, what's the "basion?" The basion is the clivus bone, and the clivus bone is the part of the skull that is just forward of the foramen magnum. Got it? No?

The foramen magnum is the hole in the bottom of the skull which allows the spinal cord that runs up inside your spine to enter the skull. In fact, when the cord gets up high toward the brain, it becomes the brainstem. The dens (or odontoid) of the C2 should NOT be poking up through the foramen magum.

Your skull rests upon C1. The portions of the bony skull that sits upon C1 and which surround that big hole, the foramen magnum, are: the clivus bone (or basion)which is anterior, or toward the front of that big hole, the foramen magnum...

the occipital condyles which are lateral to the big hole, or to each side. These two occipital condyles actually mesh together with the C1. This is what broke loose on me when I fell from the horse and broke my C1...

and...the occipital bone, which is behind the big hole (foramen magnum). Reach up behind the base of your skull and cup it with your hand...that is the occipital bone.

So...this particular measurement on my morphometrics sheet, the "basion-dens interval," is measuring from the bony part of the skull in front of the foramen magnum down to the tip of the dens, which is, you recall, the bony finger (or "tooth" ie dens) that sticks up from C2.

The specialists take these measurements and compare them to the control study of measurements taken on people without problems at the cranio cervical junction. (we call them "normies.")

My own personal data states that the "normal" readings are an average of 7.4 mm (5.8 - 9.0)

Again, the normal readings run 5.8 to 9.0 mms as a distance between the basion and dens, with an average of 7.4.

The distance between MY basion and dens?

2.4 mm.

This was when I was lying down, without the weight of my head on my spine.
There is data here from when I was upright under CT, and the space closes even more! 2.2, 2.1 and 2.9 mm are recorded.

So, this seems to project, obviously, that the dens is much closer to the basion or clivus than it is supposed to be! No brag, just fact.

I mean, a lot closer.

So that I won't fry your brain with this I will close here and start a new post, a continuation of what I see in my morphometrics. If your eyes haven't glazed over, that is!

2 comments:

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By His Grace said...
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