Eye injuries

[juszczec]

Doc

I was talking about the body's anatomical weak points with the worst person possible, another martial artist.

He said some things that strike me as incorrect, but I don't know enough about the body to say so.

That's why I'm here.

How much force is needed to damage the eye and windpipe? He claims (if I read him correctly) to have had his windpipe knelt on, regularly, and suffer no ill effects. He also claims striking the windpipe is not as dangerous as it sounds.

Something doesn't sound right to me. AFAIK, having it knelt one should be terribly painful. It might not kill you outright, but its going to hurt to the point that everything you do will be directed at stopping the pain. Also, AFAIK, being struck in the windpipe will cause pain and spasms leading to uncontrollable coughing/choking.

On to the eyes. He says that closing the eye can provide protection against a finger jab. I say maybe against a flicking/long range strike but if you hold the head still and shove a finger in from close range then closing the eye won't do much to stop it.

Are my facts correct?

Mark

[doc]

I was talking about the body's anatomical weak points with the worst person possible, another martial artist.

Yes, probably a true statement. Let's look at the facts, shall we? Got some interesting points in this request.

Let's talk about the windpipe (trachea). I think I've already discussed this in a previous section. It all has to do with pressure, and, pressure divided over an area, or, in terms that you probably are more familiar with, pounds per square inch. If we go back in time a bit, and look at women's shoes, you'll see what I'm getting at. Presently, women use heels that are rather large; they might be tall, but the more important consideration is, how big they are diameter wise. A heel that has a large diameter is going to exert a downward force, dependent upon the woman's weight, over the area of that heel. A heel of a large diameter will exert less force per square inch, than a heel of a very small diameter. One reason why women's heels of long ago, the so called "stilleto heel", or the spike heel, were not so popular on linoleum floors in people's homes, was the fact that the tiny heel left impressions in the floor. Especially if you put the typical bitch that goes out with me in set of shoes like that. They were particularly hellacious on ice; the smaller surface area with a given force offered more compressive power, more compressive power led to increased localized ice melting, which led to more slipperiness and less traction. Given the same amount of weight or force, the smaller the area that is exerting that force, the more penetrating power that object has.

Same thing goes for body parts. The trachea, as I've discussed in a previous thread, is made up of cartilaginous rings, which, though provide good support for the trachea, and protection from collapse given external pressure, is not immune to compression, fracture, or impingement. If you take an object with a relatively large surface area (such as a forearm), and strike that against the trachea, the trachea would be more likely to withstand that blow as compared to a finger strike. It all has to do with "pounds per square inch", or, amount of force distributed over a certain area. Also, with respect to the neck, the rather large sternocleidomastoid muscles on either side, can be "tightened"; they can support significant weight. This kneeling on someone's neck nonsense has more to do with the sternocleidomastoid muscles supporting the comparatively large object (knee), than it does a tough trachea. Yes, it's impressive. Almost as impressive as the fifty emails I get each day about some pill that will add a foot to my dick. If he really wants to impress someone, hit him in the trachea directly with the but end of a broom handle. Now that would impress me.

As for the eye, the eyelid does provide protection, and lubrication, to the surface of the eye. There is a small cartilaginous plate in the eyelid, which gives it some rigidity. A glancing blow to the eye would most likely be deflected by the rather thin eyelid; remember, the eyelid is not that significant a structure, but, it is effective for keeping small objects, or, large objects of small velocity, from damaging the eye. However, and again, it all has to do with pressure distributed over area, the eyelid is not going to offer much protection for someone who suffers a strike from a small object (finger) moving at a great velocity (and thus, increased force). The eyelid just does not have the strength to resist that.

Since the eye lives within the bony confines of the skull (see picture below), there is not much "give" when it comes to direct frontal trauma. The eye can only move back so far; the eye itself, has only so much "give". It is a fairly flexible organ, but, since it is filled with a thick viscous fluid (remember, fluid is non-compressible), the eye itself is not going to compress with blunt trauma. It will deform however, which can lead to lens disruption, retinal tears, and internal hemorrhages. Given enough force, the globe of the eye can rupture. To think that a "strong eyelid" will protect someone from eye damage after a finger strike is almost as nonsensical as me taking this VP RX shit to make my johnson huge. God, don't I give enough pleasure to these women as it is...

Pictured below, you can see a dissection of the orbit cavity, from above. On the left, you can see a clearer picture of the globe of the eye, with the white optic nerve trailing behind. The brownish structures attached to the eye are the extraocular muscles, which are responsible for eye movement. The top part of the orbit has been removed so you can see inside, but, you can get an idea of the space inside this by looking at the medial and lateral sides of the orbit. The eye is in there fairly tightly, any compressive force from the anterior (upper) direction that pushes the eye deeper into the orbit, is really not going to be able to push it that far. The eye itself will yield, thus causing damage. Also from the picture you can see how difficult it is for a blow to force the eye out of the socket; however, this can occur given the right amount of force, and the right amount of hemorrhage behind the eye in the bony orbital socket. Note that I don't have a picture of the eye itself dissected; generally, when you remove the fluid from the eye, the eye just collapses like a balloon.

[doc]

Here's a view of the eye in the bony socket of the skull, again with the upper portion removed, though, in this image, you can see where the bony roof of the socket at least starts. Again, you can see the globe of the eye (number 3), lying behind the lacrimal glands (the sponge like structures over the lateral portion of the eye, numbers 1 and 2), and the various extraocular muscles. This image, from the side, gives you an idea of the amount of space within the bony orbit, and the relative natural position of the eyeball.

[doc]

The image below is a shark eye, which has been dissected. It's similar in that the structure is a globe made of up tough material, the thickness of the shark eye, however, is more significant than the human eye. I think that the structure to the right is the retina, the stuff to the left is the lens and pupillary area. It's also a hell of a lot bigger than a human eye, but, you can get an eyedea as to how the human eye is made from this. Note Bene that the eye does not have siginificant structure on its own without the internal vitreous humor liquid inside, which keeps the eye under pressure, and "inflated".

[matan]

Xie Xie

Thanks for sharing those pics with us Doc.......Interesting....never saw a dissected shark eye.....LOL
(by the way- got the java problem fixed)...

[Steve]

Yumm..

Yum Shark's Eye... Kinda looks like the Steamed Dumplings we get.

[baljeet]

1 question where you getting all these photos?

what does it mean when i eye seems to flicker? not in a mental institute way but you can feel it? any one got any ideas?

[doc]

Blinking is normal, occasionally, sometimes due to nervous or drug conditions, the eyelid can "flicker".

[baljeet]

cheers, that helps me and my flickering eye sleep better.

[LeiYunFat]

Does being punched in the eye/face lead to uneven eyes? I've noticed that my pupils no longer focus on the same spot. They also do not move in unison.

But after experiencing my eyes being this way, I've noticed that many people have uneven eyeballs. Is there a general explanation for this as well?

[doc]

If your pupils no longer focus on the same spot, then I would safely propose that you shouldn't be able to type your posts, and read the forum. If your eyes are "uneven", that is, if the central focal points of your retinas do not match as to where they are looking, you'll have double vision. Unless you've had it long term, after which the brain kind of adjusts to some degree (ignoring one image).

Differences in pupils are common. It's the iris that is different from eye to eye, in coloration and shape. Sometimes its genetic, sometimes it's from post op changes. Occasionally, it will be from post traumatic eye injuries.