Wednesday, December 30, 2009

SPARE RIBS

Sherlock Holmes (Robert Downey Jr.) is a brilliant sleuth but a lousy anatomist. At the very beginning of this delightful film(1), Holmes narrates a sequence of strikes he is about to execute on an adversary, predicting the physiological results from the various blows he will inflict.

Mr. Downey as Sherlock Holmes.
Get me some barbeque sauce for those ribs(2)!

What is this big faux pas in the context of this narrative? The statement that took me a full three minutes to recover from? Holmes says he's going to punch this guy in his floating ribs, and poke them into his liver. Argh! See what I mean? This is so elementary, my dear Holmes! There are no floating ribs over the upper right quadrant of the abdomen. False ribs, yes. Floating ribs, no. Sheesh!

The liver is the big red blob in the upper right quadrant of the abdomen.
It is nestled up under your diaphragm(3). Some livers make excellent pate.

Everyone has twelve pairs of ribs. True ribs are pairs 1-7. They attach directly to the sternum, in the front of the body. False ribs (rib pairs 8-12) do not articulate directly with the sternum. Ribs 8-10 indirectly attach to the sternum. Floating ribs are pairs 11 and 12. They are called "floating" because they only attach to the thoracic vertebrae and don't make it around to the front of your torso to attach onto the sternum. Do they really float? No. They are anchored by bands of muscle. The tip of rib 11 can often be felt at the side of the waist. Rib 12 is in the back, hovering over your kidneys(4). Floating ribs are always false, but not all false ribs float.

True ribs, false ribs, and floating ribs, grouped above.

If you punch a kidney, you punch floating ribs. You could punch the liver without hitting a rib at all, but you are most likely to hit false ribs 8-10, or rib 7, a true rib(5).

Posterior view of the skeleton.
The floating ribs have the little red arrows pointing to them.

Holmes' lack of anatomical acumen doesn't keep him from incapacitating his enemies with his bare hands. I am not pooh-poohing his prowess in the manly arts, just his medical training. Great movie! Now I am hungry for skirt steak, BBQ ribs, and pate. All washed down with a pint of ale!


1. Yes, delightful. Jude Law and Robert Downey Jr., plus an allusion to resurrectionists and the dissection of criminals after their execution (which would have been a part of English culture even though the Anatomy Act of 1832 opened the non-criminal cadaver door, so to speak) plus fights, plus an evil villain looking (Mark Strong) oh-so-very Jeremy Britt truly makes for one fun movie!
2. I have a very loving and tolerant vegetarian husband.
3. The diaphragm is skirt steak in meat cut vocabulary.
4. Okay, the 11th rib also has some kidney coverage, too.
5. Don't get me started on true ribs.

Friday, December 25, 2009

HOLIDAY QUIZ!

Who doesn't feel like this at some point during the holidaze?

Answer this question by New Year's Day: List the musculoskeletal injuries that should have been sustained by Ann Darrow (Naomi Watts) during her encounter with the Eighth Wonder Of The World in King Kong (2005).*

Happy Holidays! Time for Avatar!!!!!!!!

*Theatrical cut only! 187 minutes is enough of ANYTHING. Lists need not be in alphabetical order, although it would be helpful.

Wednesday, December 16, 2009

CASINO ROeYeALE

FOR HIS EYES ONLY
In Casino Royale, Mads Mikkelsen, playing the evil villain, Le Chiffre, "weeps blood." This, in addition to what I assume is asthma, makes him appear eviler.

Why does Le Chiffre weep blood? He tells us not to be alarmed(1), that it is only a derangement of his tear duct. Now, the bloody tears thing is a great theatrical trope. When I heard this statement I laughed out loud in the theater. It reminded me of the people with the bleeding eyes from the X Files episodes 'way back in the... 90's?

If you Google "bleeding tears" on Youtube, you will see a newsreel about this kid, Calvino Inman. He seems to have been diagnosed with hemolacria. That's like diagnosing a person who faints as having syncope(2). I find medical "news" broadcasts infuriating generally, for their tone and sensational tactics. There are also a lame commercials buttressing this clip, so watch at your own peril.

Click here for the Youtube file, I'm only the cinematologist and don't
know how to add video to this blog (yes I'm pathetic.)

This condition seems rather benign if this kid has no other underlying health issues. It looks kind of gruesome, but it doesn't seem fatal. The kid doesn't have asthma, and probably isn't evil, either.

EYE, EYE-YI!
When someone says "tear duct" they are often mistakenly thinking of the lacrimal puncta, two holes on the nose side of the eye, in the upper and lower lid by the pink part in the corner (the lacrimal caruncle.)

These holes lead to the superior and inferior lacrimal canals, which join together to form the lacrimal sac, which dumps fluid (tears) leaving the eye, into the nose, via the nasolacrimal duct.


This is why, when you cry, your nose runs. Your true tear ducts are a series of excretory ducts that squirt tears out of the lacrimal gland along the upper, outer, eyelid. Perhaps he is bleeding from here.

These models cry very convincingly, don't you think? They are so sad!
Their performance might be improved with some real blood on their faces,
flowing from their lacrimal glands.

BLOODY NOSE
When Le Chiffre tears up blood, these bloody tears would come from the lacrimal glands, seep across the surface of the eye, making everything look rosy, and then exit into the nose via the route described above. If Le Chiffre bleeds from his tear ducts, the blood would also run out his nose, making him look like a sissy, instead of evil. Calvino Inman gets a bloody nose when he bleeds tears, but he still just looks like a cute and bloody kid.

BLOODY HELL
Le Chiffre should go to an optometrist. You can't avoid a machete blade if your depth perception is screwed up from blood in your eyes. I bet the blood would clot on your contact lenses, too.


1. Who is ever alarmed for the bad guy?
2. Hemo- means blood, -lacr- refers to tears, and -ia is a "state of." So Calvino is in a state of bloody tears. I hope he has insurance to pay for that diagnosis. FYI, syncope means fainting.

Wednesday, October 28, 2009

GIMME SOME SKIN, YOU BASTERD!

I'VE GOT YOU...
Skin has a number of layers to it. In most areas of the body it is thick and tough. Here's a slide of the epidermis (top layer), dermis, and hypodermis (aka superficial fascia), which contains a lot of round fat cells. Collagen fibers from the dermis run down through the hypodermis to anchore the skin onto deeper structures of muscle or bone. The epidermis is purple in this picture because these cells have been stained with a special dye.


Pinch the skin on your forearm and roll it around between your fingers. Now pinch the skin on your forehead and do the same. Now, just for laughs, roll the forearm and forehead skin of a friend of the opposite sex between you fingers. Notice anything?

You probably noticed that there is more tissue thickness between your fingers when you lift the forearm skin. Believe it or not, the skin on your forearm is thinner than on your forehead. But the forearm skin and underlying connective tissue will seem bulkier because there's more fat there. You will also likely have more play in movement with the forearm skin, as opposed to the forehead skin, which is strapped on to your skull very tightly.

When you were pinching your skin, you also probably felt the tug pulling on the muscles and bones below. This demonstrates how hard it is to remove one's skin, on a whim.

Yes, this is a picture of back skin, but I couldn't find a picture of pincer palpation to the forehead. There are many types of massage techniques that address scarring and binding of the hypodermis.



Why pinch the skin of
an opposite sex person? Because according to the experts, men have 13% thicker forehead skin
than women(1).


















Whether your skin is male or female, it's pretty tough. It takes a lot of abuse without breaking or tearing, thanks to those tough collagen fibers. It's also waterproof because of a protein called keratin. Let's take a moment to consider what life would be like if skin dissolved when you took a shower... it's worse than a water allergy(2)!

Angelena's dress, Brad's shoes... cow skin (probably not forehead).
It's tough when it's dead, and tougher when it's alive.

THICK SKINNED
Why the sudden lesson about the toughness of skin? Because the other night I went on a date with my cartoonist husband to see Quentin Tarantino's brilliant film, Inglourious Basterds. What do the Basterds do with their dead Nazi victims? Scalp them, of course. What do they do with the Nazis who survive their encounter with the Basterds? Carve a swastika on their forehead.

I have never scalped anybody, but I have dissected a cadaver. For some people, cutting the skin off the body is the worst part of the dissection. For me, getting through the connective tissue and fat of the hypodermis/superficial fascia was my biggest gross-out challenge. (Mostly because of the fatty smell and texture.) Cutting though those layers and manually breaking through that tissue(3) was a lot of work.

The special effect Geniouses got the tissue thickness pretty well during the scalping scenes. They could have used a little more blood and fibrous mess to add fullness. Even if the scalpee was dead, he wasn't dry, and hydration and blood add volume. But hey... exceptional job! I was appreciative in the moment.

Langer's lines

See these lines on the scalp? They're called Langer's lines. they indicate lines of least tension in the connective tissue of the scalp. "Elliptical excisions achieve greatest width of tissue removal when made parallel to (Langer's) lines of minimum tension(4)." Those oval-shaped scalp prosthetics in the film demonstrated the most efficient cut to get the most tissue.


Spoiler alert! At the end of the film a certain someone gets a swastika carved into his forehead. Again, the effects are effective! They got the skin thickness right and the bleeding was profuse, too. Bravo! But did you notice how loose the skin was? At a certain point a flap lifts up and is caught on the blade of the knife. If that were really forehead skin, there wouldn't be a flap. It would be anchored by the connective tissue beneath.

Now... go eat one of my favorite snacks - pork rinds.



1. Sex- and site-dependent variations in the thickness and mechanical properties of human skin, by S. Diridollou, et. al. International Journal of Cosmetic Science, 22 421-435 (2000).
2. Yes, it's true! Some people have a water "allergy" and break out in hives when they're in the shower.
3. Yup! My instructor had been trained as a Rolfer and since many of us were massage therapists, he asked us to use our hands (gloved, of course!) to separate tissues as much as we could. Wild!
4. Scalp Surgery: Anatomic and Biomechanical Considerations, by Gerard E. Seery, MD. Dermatologic Surgery 27.9 (2001)

Thursday, October 15, 2009

FANCY FEAST

I weary of cyborgs! They are ruining my sleep. I could go on and on about implanted mechanical devices for a long long time. Enough! (For now.) Let us speak of other things -

Like what? Like what's with the cat food? That's what!

Wikus van de Merwe evicting aliens from District 9

In District 9 the aliens love canned cat food, as does our human protagonist making the transition to alien. It seems a little gimmicky to put the cat food thing in the script, but while watching this refreshing and brilliant movie, I found myself questioning what could be in cat food that a crustacean would crave? I'm sure you wondered the same thing.

The cat food obviously wasn't making the aliens high, so it couldn't be a drug-like substance. Sure, I could have assumed it was a flavor thing, like some people have for chocolate, but then I wouldn't be able to blog about it.

It's got the taste aliens crave.

I compared ingredients in seafood Fancy Feast cat food with Wardley Shrimp Pellets, to see if there were any similar ingredients. Wardleys is recommended for feeding your pet freshwater crustacean. I figured the aliens in District 9 might be closer to crawdads than lobsters, even though they are called "prawns", since they hang out on land and don't seem to require a lot of salt(1). Plus, I couldn't easily find the ingredients for prawn food or lobster food online. There are plenty of recipes for cooking prawn/lobster, but none for cooking FOR prawn or lobster.

Yum.

Here are the ingredients shared by Fancy Feast and Wardley Shrimp Pellets: shrimp(2); meat meal/by-products; vitamins B-12, D-3, and A; ferrous sulfate; thiamine mononitrate; various forms of calcium; various forms of pantothenate; zinc; manganese; copper sulfate; riboflavin; pyridoxine hydrochloride; folic acid(3); and biotin.

Wardley's also include poultry meal. If I had scrutinized Fancy Feast chicken dinner, we might have had some additional crossover.

Wow! Who knew that cats and crawdads have so much in common? Wait a minute... people need a lot of that stuff too! I wonder if there's more folic acid in beer... or scotch? I will research.



1. Although I wanted to be a marine biologist when I was very young, I know nothing about crustacean essentials. But I did catch a lot of crawdads when I was a kid.
2. Aren't shrimp prawns? Ugh! It's like feeding cattle meat by-products.
3. Wait... isn't folic acid vitamin B-9 or something? Why don't they just say that?

Thursday, September 24, 2009

SMORGASBORG #7: Endoskeletons part B

What do Sam Worthington, Peter Weller, and Will Smith have in common? They're all dreamy, and they all play characters in movies who have devices implanted into their bodies. In their films the only issues they seem to have with their artificial parts are emotional ones, but putting a foreign object into a human body without adverse physical effects is actually pretty hard to do.

Marcus.
Note the chiseled endoskeletal cheekbones.

Marcus (Worthington) in Terminator Salvation, is apparently the lone humanoid organism to have survived Skynet's experimentation to build a cyborg with a metallic endoskeleton. Why would this be so hard? (Other than the fact that a machine dominated society using humans as lab rats wouldn't really care that much if there were a lot of casualties.) Living tissue and many types of metals have problems getting along together.

YOU PUT WHAT, WHERE?
Metals for making cyborgs, or hip or knee replacements, have to be corrosion resistant and biocompatible. If you have an allergy to nickel, you sure don't want a nickel implant, or a nickel belt buckle, or a phone with nickel in it.


Metals shed ions. In order for the body to tolerate the metal well, it can't leach too much into the surrounding tissue. Although your body uses some metals for metabolism (copper, iron, magnesium, etc.), too much can cause toxicity. You don't want that metal plate in your head shedding too much of anything near your brain(1).

So you can imagine that corrosion resistant types of metals, plastics, or ceramics, would be a good idea. Using incompatible metals could interfere with normal tissue growth near the implant(2). Blood acidity and ph balance can have a corrosive effect on metals. If metals shed into the bloodstream, your whole body may have a (systemic) reaction. Organs that filter blood, like the liver and kidneys may accumulate unhealthy amounts of metal ions, which is bad. And don't forget cancer! You have to be careful that whatever you're implanting isn't carcinogenic 20 years after you've implanted it.

Cobalt-chromium alloys, stainless steel, and titanium have been reported to have minimal tissue reactions in rabbits, dogs, and people. If Terminator Salvation was going to be really accurate, we should have seen some rabbit cyborgs hopping around killing humans.


Although there are always many things to consider, many people enjoy their artificial joints (made of plastics and metals) or eye lenses (plastics), or boobs (silicone) and never have any problems. 300,000 women per year receiving breast implants can't be all wrong, can they(3)?


CYBORG FATIGUE
Once you find biocompatible materials to implant in the body, you also want them to last. Fatigue resistance is important. You don't want parts to break or bend like a lug nut on an airplane wing.

If we're talking about hip replacements, "... chrome is favoured if tensile and fatigue strength are required, titanium is favoured if load sharing with adjacent bone (uncemented prostheses) is required (titanium has a similar modulus to cortical bone)(4)." So it really depends on what you're going to do with that hip and whether you glue the prosthetic, or just jam it in there really tight.

Bo Jackson, cute enough to be a cyborg, and a super-human athlete.

The metal and the bone it's embedded in, making up the structure of an artificial joint, are able to withstand normal physical stresses. Professional athletes with joint replacements often end up with complications because they put super-human stress on their bodies. The metal may bend, the bone holding it may break, or the prosthetic starts to work its way lose. For this reason, RoboCop with his combination of exoskeleton and implanted sensory parts, Spooner and his entirely prosthetic limb, and Marcus with a full body endoskeleton are the creme de la creme of the Hollywood Cyborgs.


1. Which is why they use titanium or niobium in the skull.
2. This can lead to chronic inflammation and scarring in the area.
3. Women with breast implants do not qualify as cyborgs.
4. Page 394 from Imaging of the Hip and Bony Pelvis: techniques and applications, by Arthur Mark Davies, Karl J.Hohnson, Richard Wihehouse. Read it on Google books, otherwise it costs over $200!

Friday, September 4, 2009

SMORGASBORG #6: Endoskeletons part A

A NEW WORD
Before we get started on the cyborg thing, I'd like to introduce a new term I coined last week due to a wicked cold (or maybe it was H1N1...). What is this term? Boughing. Cough so hard you try to barf, and there you have it. It's practical and combines two signs(1) of illness into one convenient word.

RoboCop isn't smiling because he's sensitive about his teeth

Might RoboCop bough? Certainly. He has a digestive system(2), such as it is, and a respiratory system. Just because he is mostly metal exoskeleton doesn't mean he can't catch a cold.

Might the Terminator bough? No. He has no respiratory system that involves lungs, and no digestive system providing an esophagus for vomit. Come to think of it, he doesn't eat food, and therefore has no vomit. Come to think of it, we don't know that he even has a functional transversus abdominis(3), the muscle that does most of the work during forced exhalation, like coughing.

Transversus abdominis is the deepest (and most petulant)
of the muscles at the waist.

YOU KNOW THIS ALREADY
Exo- means "without" or "external" while endo- means "within" or "internal." Marcus (Terminator Salvation) and the Terminator (from the great state of California) are excellent examples of cyborgs with endoskeletons.

A variety of Terminator endoskeletons

It seems that the Borg don't necessarily have to have endoskeletons per se(4). Some of them appear mostly organic with a new eye and exoskeletal structures. The Queen, however, has an endoskeletal cranium and vertebral column mounted in a machine structure with other fleshy parts. She's hard to figure out.

The remains of the Borg Queen

The implantation of fabricated devices into the cyborg is what interests me about the whole endoskeleton thing. Even Pearl from Cyborg(5) has this type of physiological intimacy with technology. This is really where the metal hits the meat.


WHAT TYPES OF MATERIALS CAN YOU PUT IN A LIVING PERSON?
For decades, people have been walking (and running and dancing) around with all sorts of artificial devices imbedded in their bodies. The list runs from simple screws to hold broken bones together, to artificial joints, to cochlear implants, to artificial corneas... and don't forget the occasional misplaced hemostat!

Why would some people say he was a cyborg? Because he has a cochlear implant.

Scissors in a patient, from an interesting blog called The Sterile Eye

As long as surgeons have been implanting devices (accidentally and on purpose) they have also been taking copious notes about the substances those devices are made of. It turns out that finding the right material to do the job is harder than you'd think.

Next time we look a different physiological reactions to implants.



1. Remember, signs are objective, observable, data like coughing or vomiting. Symptoms are subjective, like a sore throat or nausea.
2. It just occurred to me. RoboCop/Murphy has teeth but eats the equivalent of babyfood. If he doesn't chew and exercise his teeth, they will get soft and weak. Do they give him dentures in RoboCop 2?
3. The transversus abdominis, along with two other muscles at the waist, the external and internal obliques, are commonly known as bacon in our porcine friends. Hey... it's a theme! H1N1 is swine flu, and now I've mentioned bacon!)
4. If anyone proficient in Borg lore wishes to comment and educate me, please do!
5. What a bad movie that was.

Monday, August 17, 2009

SMORGASBORG #5: Exoskeletons part D

PRACTICAL APPLICATIONS FOR EXOSKELETON TECHNOLOGY
considering the devastating nature of brain and nerve injury, it is no surprise that people are very excited about research in the areas of biomechatronics, robotics, and other areas exploring ways to support and/or rehabilitate people with weakened or paralyzed bodies(1). Here are some examples of exoskeletal technology put to better purpose than superhuman strength and killing people. According to my constructed definition of a cyborg in SMORGASBORG #1, these thing wouldn't qualify one to be a cyborg because they lack an information exchange between the machinery and the body wearing it. But what the heck...

There's a video ad of the suit at this link, but a better version is on YouTube.

A company called Argo Medical Technologies is developing an exoskeletal system for the legs. The exoskeleton, called ReWalk, doesn't provide an exchange of information between it and the wearer. You have to cue actions individually. The suit doesn't know if you want to go up one stair, or five(2). But who cares? It's so cool! There's a control panel that you can strap to your wrist. You cue ReWalk by pushing a command button that says something like "stand up." Then you cue the suit that you're ready to stand by tipping yourself forward, and the suit stands you up. Crutches have to be used to help maintain balance. It looks a little cumbersome, but trying to get a wheel chair up even one step can be really hard.

(If I have to listen to one more Western newscaster say
"Domo arigato, Mr. Roboto" one more time - I'm going to SCREAM!)

Above is a link to a video about a Japanese company called Cyberdyne! Argh! Can you believe it? They have been doing research, and have now started marketing a robotic suit called HAL. Argh! Can you believe it? I assume this isn't a hoax. If it is, I suspect the technology is very nearly there for this kind of thing. These suits(3) interpret nerve impulses that are trying to stimulate muscular contraction. The suit will then move the wearer's limb the way the person is trying to move it. It can give extra-human strength to a normal person, or produce normal strength for a weakened individual. It essentially anticipates and performs the movements of the wearer. In the video, they show elderly people who have suffered strokes using a half suit, and care-givers using the full body suit to carry a patient.

The full body suit's structure will hold your joints in alignment to prevent injury from forces they can't handle. The half suit doesn't seem to offer much support around the pelvis, so it might be uncomfortable if you don't have the strength to hold yourself erect for any period of time. That would limit who could use it and how it could be used.

Exoskeletal devices such as these would help someone confined to a wheelchair feel more normal and independent. Stairs could be negotiable without a ramp. You wouldn't always have to be looking up at people as they stood over you. For many people with flaccid paralysis or paresis, these types of devices wouldn't be a cure, but would provide a form of exercise(4) and potentially improve posture, which would improve health.

Luke and Yoda

The kid is using his hand for show. The sensors go on your head.

USE THE FORCE, LUKE!
Here is a trivial step on the road to great things. A toy called The Force Trainer teaches you to control a fan with your mind. Yes... a fan... yes... your mind. The fan in turn blows a ping-pong ball into the air, in a clear plastic tube, to levitate it. I can't decide if this toy is cool, or lame. Eventually, I assume that people with spinal cord injury may be able to use a brain wave sensing device that either helps them move their body, or control a robot that can more things for them, which sounds more interesting.

NeuroBoy
BETTER THAN A PING-PONG BALL...
"What is it like to mentally float an object and then hurl it far into the distance? The Adventures of NeuroBoy fulfills this classic dream by demonstrating the experience of superpowers." You can also blow things up. You wear a headset and manipulate an animated game with your mind. I'm sure it's not nearly as disappointing as it looks online.


SPEAKING OF LUKE SKYWALKER
Look at this! A "bionic hand controlled by a patient's mind and muscles." It's expensive, but probably worth it.

Enough with exoskeletons. Next time we will look at some of the factors involved in implanting devices into living tissue. It turns out that building an army of human killing cybernetic organisms is trickier than you'd think.


1. Some new devices may be able to "retrain" someone's nervous system. Some devices will not help with recovery from injury, but will facilitate more physical independence. It all depends on what caused a person's paralysis in the first place.
2. Oh! I can see the madcap Adam Sandler comedy already!
3. HAL is a lower body model. They will have a full body model out soon.
4. "Exercise" is a relative term meaning any activity that will physically challenge a particular body.