Targeting: Musculo-Skeletal Gaps

Alright... we've drifted a bit off-topic recently... shall we try to get back on track?

When we left off we'd just finished talking about the various bits of the human body that are easy to damage directly. The next set of targets to tackle are the various and sundry gaps in the musculo-skeletal system.

Let's start by clarifying just what we mean by "gaps" and why one would want to target them in the first place. The skeleton, in addition to being a rigid, jointed framework upon which to string muscle and tendon, carries around and protects the internal organs. This isn't simply a fluke of history and mechanics but rather an absolute necessity. The internal organs are fragile in comparison with muscle and bones; a design which doesn't protect them is simply incompatible with the basic rigors of daily existence. However, the human musculo-skeletal system, as good at it is at this task, isn't perfect. There are holes where the coverage is thin or non-existent; strikes which target these areas are more likely to hurt a lot, damage the underlying internal structures, and generally further the purpose of coming out on top in a fight.

Our task then is to look at the human body and identify these weak areas. For the purposes of this discussion I'm going to focus on the neck and torso; there's not much going on in the extremities and I have covered/will cover the head separately. The neck and torso can be regarded as an organ/bone/muscle complex has having three concentric layers: internal organs, then the skeleton, and then the muscle on top of that. The first two layers of this complex are shown below:

The first (fairly obvious) observation is that we should show a preference for those areas which aren't covered by bone. This is not to suggest that, as a practical matter, you can't achieve a decent result by punching someone in the ribs. The whole concept of "targeting", however, is primarily driven by concerns over efficiency; why go through bone when you can do more damage by avoiding it entirely? Thus good targets, if they exist, will be confined to the areas demarcated in red above, namely the neck and abdomen.

The Neck

We'll start by looking at the neck. Each side of the neck has multiple layers of muscle, the majority of which are located posterior to the spinal column. Anterior to the spinal column, however, there isn't a whole lot of protective padding. The sternocleidomastoideus provides some protection to important deep structures such as the jugular vein, vagus nerve, and carotid artery, but there are a number of other structures/organs which are essentially unprotected. Especially germane within the context of single combat are the larynx and trachea since these organs are an integral part of the respiratory system. In some individuals the larynx creates a surface marker, the "adam's apple", making it particularly easy to target.

A strike to the larynx, depending on the force applied, can be disabling or deadly¹. Having been tapped in the larynx more than once I can attest that even incidental strikes are really unpleasant. Moderate force can cause muscular tears, edema, and/or hematoma²; the accompanying swelling can cause constriction of the airway (stenosis), making it difficult to breath³. A large amount of force delivered across a small area⁴ can crush the larynx, resulting in asphyxiation⁵. The failure modes for the trachea are essentially the same. Moderate blunt force can lead to tracheal stenosis⁶; greater amounts of force can crush the tracheal rings potentially leading to tracheal collapse and eventual asphyxiation.

The thyroid gland and the esophagus can also be damaged by strikes to the neck, but as a practical matter there doesn't seem to be much reason to try to target them directly. I'm unaware of any surface landmarks by which you can identify the location of the thyroid gland, making it difficult to strike effectively. Moreover, thyroid injuries due to blunt trauma are rare and generally result in impairment of thyroid function^7,8, an effect which isn't particularly germane in the context of single combat. In order to get to the esophagus from the front of the neck you have to go through the trachea, so why not just target the trachea in the first place?

The Abdomen

The musculature of the abdomen is relatively complex in comparison to the neck, so the first step in identifying potential weak spots is to figure out how its all put together⁹.

The bottommost layer is comprised of the rectus abdominus, a pair of long, flat muscles anchored to the pubic bone at one end and the 5th, 6th, and 7th ribs at the other. The pair are encased in tendon (the sheath of rectus), which joins the pair together via the linea alba, creating a single, "v"-shaped sheet of muscle.¹⁰

The next layer is the traversus abdominus, so named because the fibers of which it is comprised are transverse (perpendicular) to the longitudianl axis of the body. Like the rectus this layer is composed of two sheets of muscle, joined at the body's midline via the tendons which form the sheath of rectus. The traversus follows a boundary roughly defined by the cartilage of the 7th - 12th ribs, the lumbo-dorsal fascia, the crest of the ilium, and the inguinal ligament¹¹.

On top of the traversus are the internal obliques. This layer is best characterized as a collection of muscle fibers radiating perpendicularly outward from the curve defined by the ilium and inguinal ligament. The fibers furthest anterior along this line (and thus closest to the pubic bone) are essentially horizontal and terminate in the linea alba. As you move posterior along the curve of the fibers take on more of a vertical character, terminating in either the sheath of rectus or in the cartilage of the 7th - 9th ribs. At the most posterior end of the curve, roughly coterminus with the apex of the iliac crest, the muscle fibers are vertical and terminate into the bottom of the three lowest ribs.¹²

The topmost layer is formed by the external obliques and is a structural complement to the internal obliques. The fibers of the external obliques originate along the bottom edges and exterior surfaces of the lower 8 ribs and proceed at a roughly 45 degree angle towards the midline of the body from their point of origination. Some of them terminate in the sheath of rectus/linea alba while the remainder terminate at the iliac crest or inguinal ligament¹³.

Analysis of Abdomen Musculature

So what to make of the diagram above? What does it tell us about areas of weakness in the musculature of the abdomen? What it reveals is that the majority of the abdomen is protected by a criss-crossing mesh of fibers (both muscle and tendon) several layers thick. It follows from there that weak points, if they exist, will be found on the periphery where the muscle attaches to the bone rather than in the center. The various sheets of durable tissue overlap less at the edges than they do towards the center of the abdomen. There's also less tissue in general as the muscles thin to form the aponeuroses by which they are attached to the bones of the skeleton.

But here we run into a problem as we try to move from generalities into specifics. I've not been able to find any information on the fine anatomy of these border regions. I can't characterize the relative muscle thickness, or look for actual gaps in coverage, or talk in any meaningful way about the durability of the associated connective tissue. If anyone has done any relevant studies they're locked away someplace where I can't find them. Thus we are confronted with something of a dilemma. This blog exists to combat woo and discourage the transmission of hearsay and dogma through the use of empiric evidence. Should I remain mute, then, when the evidence runs out, or should I try to soldier on based on anecdote and personal expierence?

In this case I'm inclined to carry on and simply note in BIG, RED LETTERS that what follows is based primarily on my personal experience and isn't backed up by much of anything else besides educated conjecture. That caveat noted, experience tells me that the following represent weak points at the periphery of the abdominal muscles:

• The tip of the sternum (xiphoid process) and immediate surroundings.
• The gap between the iliac crest (hip) and the lowest ribs.
• The area immediately above the pubic bone.

Go ahead... tense you abdomen and compare the muscle tone of these areas with the tone around the navel. I'm doing just that as I write; here's what I feel:

• sternum: The xiphoid process itself is noticeably flexible and has little or no muscle covering it. The gaps between it and the costal cartilage on either side feel soft, as does a small area immediately South of the tip.
• gap between hip and ribs: Muscle tone is good until slightly posterior of the plane dividing the front and back halves of the body, but then drops noticeably thereafter. This seems to correspond roughly with the transition between the traversus abdominus and the lumbo-dorsal fascia.
• above pubic bone: I can't even say that it feels noticeably softer, per se, but it feels like the underlying muscle has less endurance and might be prone to give out under stress.

For the following discussion we'll posit that I'm not completely making things up with respect to the above. This tells us that we should thus focus on the following locations:

So let's take an inventory of the bits of anatomy in each region and go from there.

Sternum

In the area around the sternum you have:

• Diaphragm
• Liver
• Middle lobe of the lung
• Assorted lymphatic vessels
• The pericardium
• Assorted nerve plexuses
• Xiphoid process

Diaphragm

The diaphragm is essentially a big sheet of muscle whose primary purpose is to inflate and deflate the lungs. Blunt trauma can cause this sheet to rupture¹⁴, reducing its ability to fulfill this role, but the force needed to cause such a rupture is likely greater than what can typically be delivered in a combat situation. Much more common is the experience of "getting the wind knocked out of you".

Reading the Wikipedia article on the subject there seems to be some confusion regarding the exact mechanism of this particular phenomena. It is described as the result of "pressure on the solar plexus", with an accompanying link to the entry for the celiac plexus, suggesting that a strike somehow impairs the plexus thus preventing the diaphragm from doing its job. However, the following paragraph describes a mechanism whereby the sudden stretching of the diaphragm directly induces the spasm. I chalk this apparent contradiction up to confusion over terminology; "solar plexus" technically refers to a bundle of nerves, but is also commonly used to refer to the area around the xiphoid process. The discussion page for the article also includes a reference to a physiology book which suggests that a strike to the sternal region causes the forced exhalation of the lungs' residual volume. This has the potential to completely deflate the alveoli which, once deflated, take more effort than usual to refill.

Regardless of the exact mechansim there's no doubt that the effect is real and correlated with strikes to the sternum/abdomen. Getting the wind knocked out of you makes it near impossible to carry on in a fight but does no short- or long-term damage; this makes it an especially useful technique if you're simply trying to disable someone. As such targeting the diaphragm seems to be highly advantageous.

Liver

The liver is big, fixed, and fragile; blunt trauma can lead to hematoma, contusion, and vascular/bile duct injury¹⁵. None of these are immediatley disabling; there's no point in targeting the liver specifically.

Middle Lobe of the Lung

Blunt trauma to the lung most commonly causes pulmonary contusion (aka bruised lung) leading to decreased lung function¹⁶, but causing that kind of damage in the context of unarmed combat seems unlikely. The little chunk of the lung that's not covered by the ribs doesn't seem to merit special attention from a targeting standpoint.

Lymphatic Vessels

The lymphatic system is a series of vessels which carry lymphatic fluid, much like the circulatory system in many respects. These vessels are fragile and easily damaged; trauma can lead to lymphadema, the build-up of lymphatic fluid in body tissue¹⁷. Because the lymphatic system deals with low volumes of fluid it takes awhile for lymphadema to manifest itself; since the fight will long be over at that point there's no reason to care about the lymphatic system.

Pericardium

The pericardium is a fibrous sac that contains the heart and the ends of the largest blood vessels. Blunt trauma to the pericardium can cause a host of fairly serious injuries¹⁸ which, unlike damage to the liver or lymphatic system, have the potential to greatly impair an opponent. I was able to find several case studies indicating that such injuries can be caused by assault, suggesting that the heart/pericardium represents a viable target.

Nerve Plexuses

Nerves nerves nerves... there's a lot to say about them. Enough, in fact, that I'm going to postpone discussion of nerves altogether for the time being and dedicate my next targeting post to the subject.

Xiphoid Process

Yeah, you can break it and yeah, it's somewhat distracting. More importantly, its right out there in front just waiting to be punched. It certainly represents "low hanging fruit" from a targeting standpoint.

Hip/Rib Gap

This area has a couple of interesting features but is nowhere near as complicated as the area around the sternum. There appear to be two structures worth mentioning, the kidneys and the colon. Kidney trauma most frequently leads to hematuria ("peeing blood") and can, in theory, lead to general vital sign instability¹⁹. Getting punched in the kidneys hurts, but it appears doubtful that damage to the kidneys, in and of itself, can significantly cripple an opponent²⁰. Trauma to the colon can lead to bruising and perforation, resulting in hemorrhage and/or peritonitis²¹, but the latter kills slowly and I haven't run across any evidence that the former can be serious enough to matter in a fight.

Pubic Region

Lastly we get to the area right above the pubic bone; there's not a whole lot of anything here apart from the bladder. It's possible to rupture the bladder, especially if its full, but the affects of the rupture are subtle and might not be detected for days²². As such the bladder (and the pubic region in general) don't present a particularly efficacious target.

Closing Chatter

What we've discovered (or, perhaps more accurately, confirmed) is that most of the internal organs are well-protected. There are only a few gaps in the coverage provided by the skeleton and abdominal muscles which can be exploited for immediate effect. The throat is almost entirely free of bone and muscle, leaving the larynx and trachea vulnerable. Striking the area around the xiphoid process can cause sternal fractures, spasm of the diaphragm, and pericardial bruising. But other targets which initially looked promising, above the pubic bone and iliac crest, fail to pan out on closer examination. While getting struck in these areas is undoubtedly painful, damage to the associated internal organs is unlikely to significantly disable an opponent.

One glaring deficiency (and a fruitful area for future refinement) is that, while we've identified potential injuries and their effects, we've no idea how probable it is that such injuries will actually occur. Many of the case reports on which I have relied reflect injuries caused by high-speed collisions, falls, and similar occurrences, none of which match the conditions of single combat all that well. Absent more definitive information I've had to rely on my gut in judging the likelyhood of substantive organ damage. It would be very useful to understand both the range of forces which a typical martial artist can deliver and the range of forces needed to cause various injuries.

Finally, the discussion of the weak areas of the abdomen is heavily reliant on my personal experience and opinion. Rebuttal and/or better information is welcomed.

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1 One of my instructors had a particularly pithy expression for this, something along the lines of "You can turn out the lights or turn them off for good".
2 http://www.bcm.edu/oto/grand/081299.html
3 http://www.ncbi.nlm.nih.gov/pubmed/6487011
4 Such as might be generated by a shuto, leopard's paw, or ridgehand strike.
5 http://www.bcm.edu/oto/grand/081299.html
6 http://emedicine.medscape.com/article/362175-overview
7 http://findarticles.com/p/articles/mi_m0BUM/is_8_81/ai_90869434/
8 http://www.jultrasoundmed.org/cgi/content/citation/25/7/943
9 My apologies if I make any mistakes in the following; the references that I'm using are hard to follow at times.
10 http://en.wikipedia.org/wiki/Rectus
11 http://www.bartleby.com/107/118.html
12 ibid.
13 ibid.
14 http://www.sciencedirect.com/science?_ob=ArticleURL&_udi=B6T78-4WJG8S3-1&_user=10&_coverDate=09%2F30%2F2009&_rdoc=7&_fmt=high&_orig=browse&_srch=doc-info(%23toc%235052%232009%23999599990%231351075%23FLA%23display%23Volume)&_cdi=5052&_sort=d&_docanchor=&_ct=25&_acct=C000050221&_version=1&_urlVersion=0&_userid=10&md5=9f3cc4648e56a30ad52b5d6dd0c8ab6e
15 http://emedicine.medscape.com/article/370508-overview
16 http://www.trauma.org/archive/thoracic/CHESTcontusion.html
17 http://books.google.com/books?id=5Yl1LNe69lwC&pg=RA2-PA2361&lpg=RA2-PA2361&dq=lymphatic+vessels+trauma&source=bl&ots=7pngdfhncq&sig=rWFC9jKkNeFttt2wf9jzoulqNAg&hl=en&ei=22--SvT3J4SAswPToLE1&sa=X&oi=book_result&ct=result&resnum=1#v=onepage&q=lymphatic%20vessels%20trauma&f=false
18 http://books.google.com/books?id=ooH1nH81_h4C&pg=PA402&lpg=PA402&dq=pericardium+blunt+trauma+assault&source=bl&ots=41TaOYEyk8&sig=jVNPH7lyiMyKrTr6Lng5izfzYIg&hl=en&ei=6d-_SvfsGpS2swPI6tk7&sa=X&oi=book_result&ct=result&resnum=10#v=onepage&q=&f=false
19 http://emedicine.medscape.com/article/379085-overview
20 http://linkinghub.elsevier.com/retrieve/pii/S0090429504006995
21 http://emedicine.medscape.com/article/364264-overview
22 http://emedicine.medscape.com/article/441124-overview

Correction Regarding Martial Force, or, BP Web Design of Durham Engages In Questionable Business Practices

Update: See here for a discussion of the redaction on this page.

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The Director of REDACTED was kind enough to leave a comment on my post regarding someone spamming my blog. The perfidious individual is not REDACTED, as I previously speculated, nor even Martial Force itself, but rather BP Web Design of Durham.

You know the neat thing about the Internet? It brings such a wealth of information to your fingertips. For example, it tells me that BP Web Design is none other that Blaine Patton, a UK Sole Trader residing and/or doing business at

109 Front Street,
Tudhoe Colliery  Spennymoor
DL16 6TJ
United Kingdom
+44.1388810461
blainepatton@hotmail.com

What's even better is that you can figure out with whom he has a business relationship. For example, he's apparently some sort of web design for Allison Wall, owner of The Spotty Dog Shop. Like Ann and Russell from the original post, I'm sure that Allison is probably a lovely person, but she needs to know that she's outsourcing her tech to someone who's contributing to the downfall of the intertubes.

So, Allison Wall, aka alison@thespottydogshop.co.uk, here's a personal message just for you: If the Director of RS Creative Solutions is to be believed Blaine Patton is likely spamming blogs on your behalf and earning the ire of various and sundry individuals. I recommend that you give him the rough side of your tongue.

But wait, there's more! It seems that BP Web Design has also done work for the AFS Group, a vehicle financing firm of some sort run by one Lauren Turnbull. Lauren, same thing goes for you... Blaine Patton has been defacing my blog and generally making a hash of things. Are you sure you want to be doing business with him?

But you know what really makes me giggle? People leave their fingerprints all over the place. Did you know that REDACTED? Now, I know, it could be some other Blaine Patton... except for the fact that REDACTED. Coincidence? I think not!

And Jebus... would you REDACTED?