Thursday, October 31, 2013

WILTIMS #61: It's not procrastination if it's pretty!

Following histology yesterday, today was our last anatomy lecture. Makes me kinda sad. Also, do I actually know anatomy now?! Enough to pass this class? Sure. Enough to pass the boards? Maybe. Enough to go into surgery? Not even close.

But I have learned an awful lot! And hopefully you have learned a bit too by reading along with me. I only hope that I can find fun, interesting facts during the biochemistry and physiology courses during the next block, so we can keep this going. I'll have a couple more posts this week as we wrap up the remaining lab sections, but next week is all tests and studying, so pardon the upcoming radio silence.

Click to embiggen
Apropo to nothing, here is a diagram I made for our histology pre-lab assignment due tomorrow, showing a simplified menstrual cycle in relation to the maturation of an ovarian follicle and uterine endometrium:

TIL: Ears begin development below the jaw of the growing embryo. The ears don't actually move as development continues, rather the jaw and rest of the face grows out and down between them.

You can hear (with magnification) a fetus' tongue move in and out of the mouth in utero. They do this in part to get the tongue out of the way of the two halves of the developing palate (roof of the month) as it extends from the sides of the proto-face to separate the nasal and oral cavities.

Tuesday, October 29, 2013

WILTIMS #60: Sing "Ahhhh"

TIL: ...the super complicated way that we manipulate our vocal cords. Explaining it would take too long for a blog post, so instead I give you a video of a quartet singing from the inside. Enjoy!
Make fullscreen for better viewing!

There are spillways on either side of the epiglottis (the flap at the bottom of the tongue that blocks off the trachea when you swallow) that allow you to constantly swallow excess mucus while breathing.

Whales sing underwater by moving air back and forth between their mouths and their stomachs through the vocal cords. You can try this at home by taking a modest breath, plugging your mouth and nose, and trying to make noise. Sounds pretty whale-like, doesn't it?

Topical anesthetics can be used to numb/paralyse the muscles of the larynx (say for a bronchoscopy), however they don't reach the superior and recurrent laryngeal nerves. These nerves innervate the muscles of the larynx but also sense distension of the aorta. A problem can arise when the brain, unaware of the scope in the throat, interprets an increase in pressure on the laryngeal muscles as sudden high blood pressure in the aorta. This can set off a dangerous reflex where the brain tries to lower the blood pressure leading to a heart arrhythmia and even cardiac arrest.

Prescribe lemon candy for salivary stones. The lemony acidity will cause the patient to increase salivary production and reduce stagnation and crystallization of the salivary fluid.

Monday, October 28, 2013

WILTIMS #59: Splitting headache

Today I sawed a human head in half with a handsaw. So there's that...

TIL: The Eustachian tube (aka the pharyngotympanic tube or auditory tube) connects the middle ear to the pharynx (top of the throat). This canal is what allows you to pop your ears after a change in air pressure that you might experience at the bottom of a pool or flying in an airplane.

There is a muscle in the ear called the tensor tympani that is like a dampening pedal for your eardrum. It tenses when you hear an extremely loud noise, restricting the movement of the tympanic membrane (eardrum) and dulling the sound.

If you plug your ears in a quiet room, you can actually hear your own internal carotid artery which runs through the skull very near the structures of the internal ear.

Tilting your head back when you have a bloody nose does nothing (besides make you swallow blood). Pinching the nose, however, may be helpful depending on the location of the bleed.

If a kid (or really clumsy adult) trips while drinking out of a straw, they can puncture the back of their throat. This is not primarily dangerous and should heal just fine. The problem is that the retropharyngeal space that was punctured by the straw is continuous all the way to the posterior mediastinum (space immediately behind the heart). If an infection develops, it will quickly progress from a simple deep throat infection to pericarditis (an infection of the sac surrounding the heart), which can be deadly.

Saturday, October 26, 2013

WILTIMS #58: Why so serous?

We only had one 2-hour anatomy lab on the schedule today, so I don't have much to report. We were dissecting the parotid and temporal regions of the head (above, in front of and below the ear). It was not the most elegant dissection thanks to the slapdash layouts of the nerves, blood vessels and glands in relation to the bones and muscles, but we made do and managed to see most of what we were supposed to see.
The salivary glands: #1 parotid,
#2 submandibular, #3 sublingual

TIL: The parotid gland and pancreas are the only two glands that produce amylase, the enzyme that breaks down starches into sugar. The parotid gland secretes serous fluid, including the amylase enzyme, into the mouth via a duct that can, on rare occasions, become occluded causing the sides of the face to swell. This condition is easily confused with the mumps, which also results in the swelling of the parotid gland, but from the inflammatory action of the mumps virus rather than the obstruction of the parotid duct.

Seizures originating in the temporal lobe are associated with the perception of an strange smell. These seizures can be caused by radiation from the treatment of salivary gland cancers located in the parotid gland.

Friday, October 25, 2013

WILTIMS #57: Gone fishin'

Today was a long but good day filled with fun, mostly extracurricular goodies.

On the brief curricular side of things, we had yet another histology lab (only 2 more!). This time we were investigating the skin... and a monkey fingertip.

This afternoon I got to step back over to the patient side of medicine at my first appointment with my new oncologist. I was first seen by an oncology fellow* working under the main doctor. It was fun chatting with (and silently judging) someone who is, though already 10 years ahead of me, still completing his training. When my actual doctor came in, it was entertaining watching him simultaneously tend to me and teach his student.

After my appointment (everything looks good btw), I ran back to campus to play in our final flag football match of the season. We were crushed by a team of second-years, but they were such good sports that we still had a blast.

After the game, I quickly changed and headed back out to a neurosurgery interest group meeting. We met in the radiology conference room in the hospital and, unlike other interest group meetings I've attended, were greeted by not one, but easily half a dozen doctors, fellows and residents. The head of neurosurgery welcomed us and then a pediatric neurosurgeon presented on current interventional techniques for common maladies.

TIL: The skin contains three types of glands: two sweat glands and one that secretes an oily substance called sebum. This third secretion is released by a holocrine gland which emits its cargo by literally filling up until it bursts. Accordingly, your skin perspires sweat, oil and cellular debris.

A bone marrow biopsy is not indicated for a stage 2 Hodgkin's lymphoma patient (hopefully the fellow learned this too!).

When a cranial suture (the border between bones of dome of the head) fuses earlier than normal in a child, the head will elongate in the direction parallel to the suture. This is called craniosynostosis and doesn't usually cause and neurological deficits directly. But because children aren't generally as nice to a kid with a noticeably oblong head, if the defect was not corrected the child is almost certain to suffer socially and subsequently educationally.

Young children recover extremely well from cranial surgery thanks to their still-developing skeleton. A 6-month old could have the entire surface of the skull removed and grow it back within weeks.

Neurosurgery before good imaging techniques were invented used to be described thusly: For a hobby you can either do fishing, hunting or neurosurgery. Your prey never survives, but at least you can have some fun.

*For those unfamiliar with the ridiculously complicated nomenclature for students of medical education:

  • 1st-2nd year of medical school → medical student
  • 3rd-4th year of medical school → medical student/sub-intern
  • 1st year of residency → intern and/or doctor
  • 2nd-6th year of residency (usually 3-4 years) → resident and/or doctor
  • 1st-4th year of fellowship (usually 2-4 years)→ fellow and/or doctor

Wednesday, October 23, 2013

WILTIMS #56: Teeth and triangles

Click to triangulate
Today we had a surprisingly enjoyable anatomy lab dissecting the anterior neck and paralingual space (area under the jaw). Some combination of our cadaver and our dissecting skill resulted in a beautiful display of muscles, blood vessels, glands and nerves (except that damn accessory nerve [shakes fist angrily at the anatomy gods]). We received many a compliment and actually learned quite a bit... mostly about triangles.

TIL: Teeth provide proprioception for the mandible (i.e. send the brain information about the location and movement of the jaw). When dentists numb your teeth while performing their acts of torture, they tell you not to eat for a few hours after. This is not because the dental work needs time to set, but rather because your numbed teeth are temporarily unable to let you know their location, so you risk biting your cheek or chomping down extra hard on your newly fixed smile. This also explains why people with complete dentures have a hard time biting and chewing smoothly; they no longer have accurate information about the movement and location of their jaws! Interestingly, keeping just one tooth would be enough to maintain this sense.

WILTIMS #55: BIC pen to the rescue!

Today was a day of battling the urge to nap ...and losing. The heat has been on noticeably high in our primary lecture hall and as a result, you can see so many heads drooping and then jerking awake you might think you watching a metal concert in slow motion.

TIL: Like in the digestive system, the ureter is covered with both a longitudinal and circular layer of smooth muscle. In the ureter, however, the longitudinal layer is the innermost layer covered by a circular layer - the opposite of the layering of the digestive tract.

In the event of a potentially lethal ventricular tachycardia, you can attempt to calm the heart by stimulating the vagus nerve. This can be done by massaging the carotid bulb (the lowest section of the internal carotid artery in the neck). However, you have to be careful not to put too much pressure on the artery or you can risk the patient passing out.

When performing a tracheotomy, you stab between the first cartilaginous rings of the trachea below the thyroid cartilage. Usually the thyroid gland (which looks like a butterfly from the front) is low enough not to be in the way but occasionally it reaches up and blocks your path. What do you do? Cut it in half! The thyroid gland doesn't have a duct; it secrets directly into the bloodstream which it accesses bilaterally. This means you can cut the thyroid right down the middle with no noticeable effect. Push the two halves apart and insert the tracheal tube.

Tuesday, October 22, 2013

WILTIMS #54: Eye spy

Today we explored the orbit (socket) of the eye, both in lecture and in lab. The eye is incredible both as a complex sensory organ and as a clinical tool. The movement of the eye is controlled by six muscles which are innervated by three distinct cranial nerves. This apparent inefficiency is a great diagnostic tool for classifying nerve or brain damage and the reason for those seemingly bizarre "follow my finger" eye tests.

In lab, we skinned the eyelids and explored the tear glands and ducts. We then turned to the space behind the eye, which was only accessible by breaking through the roof of the orbit with a chisel. The complexity of the eye was finally exposed after nearly an hour of meticulously clearing out all of the fat that cushions the eye and associated muscles, nerves and blood vessels.

TIL: The superior rectus muscle of the eye is innervated by the same nerve as the superior levator palpebrae, the upshot of which is that you can't look up without pulling the upper eyelids up as well.

The superior oblique muscle (the topmost muscle in the accompanying diagram) actually uses a naturally formed pulley system. In order to exert more force on the eye, the muscle passes from its attachment on the eye through a tendinous loop called a trochlea (literally: pulley wheel), before finally travelly to the back of the eye socket.

Tarsal glands are located on the edges of the eyelids and secrete an oil that both keeps the eyelids from sticking together as you blink and acts as a hydrophobic barrier, keeping the tears within the eye.

The lacrimal caruncle (literally: teary meaty lump) on the nasal side of the eye surrounds a duct which siphons excess tear fluid into the nasal cavity. Ever notice that when a person gets misty eyed, they start sniffling? Turns out the bulk of  fluid that ends up in their tissue is tears, not snot. The tears are secreted from the outer upper part of the eye socket, flow over the surface of the eye, are held within the socket by the oil on the eyelids, collect near the meaty lumps and drain into the inferior nasal meatus of the nose.

During embryonic development we form remnants of gill slits that we inherited from our common ancestor with the jawless lamprey eel. The tissue between these slits eventual develop into the jaw, hyoid bone, and the cartilaginous structures of the pharynx and trachea. Bony fish evolved a covering over their gill slits and, sure enough, embryologically you can see the analogous human structure that forms from this covering: the external structures of the ear.

Saturday, October 19, 2013

WILTIMS #53: Brains and lightsabers

Yesterday was a dramatic day that concluded months of waiting on a couple fronts.

First up was learning how to perform an HEENT (head, eye, ear, nose, throat) exam, which meant finally getting to use the most expensive single item we've had to buy for medical school: our ophthalmoscope/otoscope (eye/ear scope). The cost was particularly annoying because it's not obvious why we need to buy one of these devices in the first place, as they are provided in every exam room and hospital unit in the country. Now, we didn't need to buy the fanciest model, but it was part of a bundle with our blood pressure cuff, reflex hammer, tuning forks, etc, so I splurged. Anyways, it was nice to finally get to use some of this doctor-y stuff!

To examine the eye with an ophthalmoscope, you start out about a foot away from the patient and place your thumb above their eye (to reassure them that you won't smack them in the head with the scope as you move in). You then align the beam of light with the pupil by looking for the “red reflex” which is weirdly named as it is merely the light reflecting off the retina on the back of the eye. This same phenomenon causes red eye in photographs. After finding the red reflex you move closer to the eye, being sure to keep the light centered on the pupil. Once you get close enough, you can see the blood vessels in the back of the eye. In order to see the vessels clearly, you have to counteract the lens of the eye by focusing the lens in the scope. Interestingly, people with different glasses prescriptions will need a different focus setting on the ophthalmoscope.

In anatomy lab yesterday, we finally reached the apex of the class: cutting open the skull and removing the brain. The day before, we had removed the scalp, so we started by placing a rubber band around widest circumference of the skull to mark out our planned cut. We then took an electric oscillating circular saw and cut through the bulk of the skull, trying to leave a small part of the inner surface intact to protect the brain. Oscillating saws, rather than rotary saws are used to cut through bone and casts because they have a much harder time ripping through soft tissue. Next we used a rubber mallet and chisel to break the remainder of the bone and finally expose the brain.

One cool thing about the interior of the skull is that it has indentations in the bone from the blood vessels of the dura mater (outermost meninx). These meningeal layers are the last thing we had to remove to see the brain, which looked... exactly like you'd expect a brain to look. It felt rather rubbery and stiff as a result of the preservation process.

Literally 5 minutes after I was touching the brain of a dead person amidst the smell of burning bone and flesh, I was waiting at a bus stop to leave town for the weekend. More than anything I wanted to turn to the other bus-riders and shake my smelly hands at them yelling, “Brains!” I managed to hold back my impulse, but let this be a lesson to you - you never know if the guy next to you on the bus was touching brains five minutes prior.

Friday, October 18, 2013

WILTIMS Preview - Brains and lightsabers

It's been an amazing, fun-filled day. I learned how to do an HEENT exam, how to use my $600 glorified flashlight, how to cut open a skull with an electric bone saw, and what the consistency of a human brain is. But I also travelled to see my significant other, so I'm deferring writing about my super awesome day until tomorrow. See you then.

WILTIMS #52: Pursuit of hoppiness

Our surprisingly deep simile for the day: Cranial nerves are like country club members; they think that because they spend time in an exclusive place that they are somehow different from the rest, but in reality they are not. ~Awesome Anatomy Professor

TIL: The eardrum is innervated by the same nerve as the muscles for chewing. This is a vestige of the evolution of the ear, whereby the ossicles (little bones) of the ear originally developed from outgrowths of the jawbone.

The vagus nerve innervates (among many many other things) the taste receptors of the epiglottis. Unlike the taste buds in the tongue, which can detect a cornucopia of flavors, these specialized receptors are responsible for detecting the taste best described as the hoppiness of beer. This is why professional beer tasters will often try to splash the beer to the back of the mouth, skipping the tongue, to get better feel for the hoppy flavor.

Thursday, October 17, 2013

WILTIMS #51: Eye to eye

Today we came face to face with our cadavers for the first time. Up until now, we had kept the cadavers' heads covered, in part to keep them from drying out prematurely, but mostly because it's the most disturbing part of working with human bodies. After over two months of skinning, slicing, tearing, and prodding, nothing can phase us. I will say that the half open eyes were a bit disconcerting.

TIL: While motor innervation of the muscles for facial expression are supplied by the facial nerve (Cranial Nerve VII), the sensory input from the skin on the face is communicated via the three branches of the trigeminal nerve (CN V).

You haven't gotten all the way to the bone of the skull until the metal probe makes a "ping" noise when you tap it.

In the surprisingly lyrical words of my anatomy professor, the superior sagittal sinus is one of the main veins that drains the brain.

Tuesday, October 15, 2013

WILTIMS #50: Alas, poor Yorick!

My study-skull and my roommate with his
A new day a new anatomy block! Once again, mere hours after finishing our exam on the previous unmanageable load of material, we are buried in even more. This block is on the head and neck and to aid us in studying the complex 3D structure of the skull, we have each been given an actual human skull to share with a partner. Since there's an odd number of people in our lab section (and I'm masterfully skilled at Rock-Paper-Scissors), I get my own! He keeps me company on my desk and listens to my soliloquies. 

TIL: Because the bones of the skull of a newborn have yet to fuse, there are soft spaces between them. The larger spaces, such as at the junctures of more than two bones, are called fontanelles. Fontainelle translates to "small fountain or spring" in old French, and these soft spots were given this name because in just-born babies you can actually see the blood pulse and gurgle within the meninges.

The mastoid process of the temporal bone (the big bony lump behind and below your ear) is not present in newborns; it develops due to the sternocleidomastoid muscle pulling on it as you grow.

The mental nerve innervates the skin on the jawbone on either side of the chin. It was named this because of how people massage their chin while thinking, and originally, it was thought that this manual stimulation could somehow pass through the nerve and affect the brain.
The sella turcica of the sphenoid bone

One of the features of the sphenoid bone is called the "sella turcica" or "Turkish saddle" which it apparently resembles because it has 4 horns (see animation on the left).

And finally, my favorite cocktail trivia piece from today: do you know where the temple on the side of the head gets its name? There are quite a few well-reasoned urban myths regarding prayer and whatnot, but these are totally off-base. As a clue, the temple shares it's name with the temporal bone over which it located.

Do you have your guess?

Both features are named for the passage of time, specifically because the hair around the temple is usually the first to turn gray as we age.

WILTIMS #49: Mnemonics

Only a pair of anatomy tests today, so I don't have anything new to share. I will, however, leave you with a couple mnemonics.

First, for remembering the carpal bones of the hand:
Some Lovers Try Positions That They Can't Handle
Scaphoid, Lunate, Triquetrum, Pisiform, Trapezium, Trapezoid, Capitate, and Hamate

Second, for remembering the order of the anatomic entities that pass under the flexor retinaculum of the ankle:
Tom, Dick And Very Nervous Harry
Tibialis posterior tendon, flexor Digitorum longus tendon, posterior tibial Artery, posterior tibial Vein, tibial Nerve, and flexor Hallucis longus tendon

Saturday, October 12, 2013

WILTIMS #48: Groans

Today we only had one one hour lecture, so I don't have much to report. The topic was clinical correlations of lower extremity anatomy, which lead to many a groan as we watched every major traumatic athletic injury in recent memory.

It's been amusing how each lecturer has treated these grotesque images. Our course director used them sparingly and with an impressive degree of nonchalance. The radiologist warned us in advance and even said that the squeamish could cover their eyes until we had passed the slide. The surgeon, on the other hand, displayed his dozens of examples with enthusiasm and theatricality. As he was speaking today I happened to be sitting next to the course director. He groaned and winced just like the rest of us.
The reactions of teammates to Kevin Ware's broken leg (you've been warned)
TIL: The singular form of the word meninges is meninx. The meninges are the three layers of connective tissue (the dura mater, arachnoid mater, and pia mater) that cover the brain and spinal cord. And since they are almost exclusively described together, we never use the singular. Meningitis is the inflammation of the meninges, which is particularly dangerous because it can damage the enveloped nervous tissue. The meninges also have poor blood supply,  limiting both the body's immune response and the effectiveness of medications.

Friday, October 11, 2013

WILTIMS #47: Candy and ice cream!

Today we had our last radiology conference until our 4th year radiology rotation. We love this professor, in part because she's nice and enthusiastic and in part because she bribes us with candy, so it was a bittersweet day.

Continuing with the treating of medical student like kindergarteners, we split into teams to try to diagnose bone fractures. Our professor is a big sports nut, so our team names were the Giants, Jets, Bills and, for lack of another NY football team, Team USA. Eli Manning and the foundering Giants were a frequent target for jokes, especially given the number of jerseys in the crowd from fans hoping for a win tonight. 

TIL: A slipped capital femoral epiphysis (SCFE) fracture is a Salter-Harris type 1 fracture through the physis of the head of the femur. Sorry, it's fun to do the jargon every once and a while. So, there is way to break your leg at the hip joint where the top of the leg bone slips off it's base. In fact, it's sometimes called an ice cream cone fracture because on x-ray it looks like someone's ice cream is about to fall off the cone.

Thursday, October 10, 2013

WILTIMS #46: Motivation

Sorry, this is a long one but it's important to me ]

Today I Remembered: ...why I'm doing all of this work.

In our small group session this afternoon, we had a guest instructor and we were asked to introduce ourselves and briefly say why we decided to be doctors. This prompt elicited a hearty mix of chuckles and groans from my classmates and myself because we had to answer this question ad nauseum during the application process, and hoped we were done with it for good.

As the circle approached my end of the room and everyone sheepishly said the same tried and true response ("I love science and want to help people."), I started to think. You know what? We aren't applying anymore, so we can say whatever we want. We're like retired politicians that can finally speak from the heart instead of from party lines. If I'm honest, what is my motivation?

My classmates moved too quickly for me to come up with a succinct response, so I barfed up some barely coherent line about my family and how the profession can be selfless. I'm still not sure where I was going with that. The class moved on and I put that thought on the backburner while I self-destructively criticized my inability to speak (normally not a weakness of mine).

My big activity for the day was way outside my comfort zone and I had been nervously looking forward to it all week. I signed up as part of GHHS NYMC Cares Week to volunteer at the nearby homeless shelter. A group of ~8 medical students would go give a presentation on diabetes and hypertension to the residents of the shelter. I was the only first-year to sign up for this activity and would be working with 2nd and 4th year students who, might I add, had already taken physiology, pathology and pharmacology and were thus much more reliable sources of health information than myself.

The older students turned out to be incredibly welcoming. They loved to reminisce about their first years and give tips on how to survive mine. When we got there we found that we wouldn't be able to use our Powerpoint presentation and would instead print out the slides to pass out to the residents. While we waited for the printer, we mingled in the activity room. Residents started to assemble and quickly grew restless waiting for something to start. As much as I like talking with the immeasurably cool 4th years, I felt more and more awkward ignoring the people we had come to (theoretically) help, so I went over and introduced myself to a particularly antsy older man.

We casually started talking and had a great conversation. It turned out that he was a cancer patient (like myself, for a time) but that he had refused to continue treatment after 10 years of chemo. I told him that I could understand his choice, and we commiserated for a while about nasty diseases, nasty doctors and nastier hospital food. By this point the rest of the medical students had followed my lead and dispersed amongst the residents and were engulfed in animated discussion.

The presentation began once the printouts arrived and almost immediately we began fielding questions. It seemed everyone in the audience had diabetes, hypertension or both - and the few who had neither were hypochondriacal enough to have questions anyway. And you know what? We answered every one of their questions. I could actually help real live people (and not just my mom over the phone)! True, I knew the least of all the students, but I still could chime in to clarify things and share the little I did know.

The highlight of the day for me was prefaced by an awkward moment where two residents asked questions at the same time. The more deferential of the two waited and was eventually forgotten amongst the continued discussion. After the presentation was over, I went immediately to that man and explained that I had not forgotten his question and that it was actually a really good one. He had originally asked if potassium was good to take for the cramps he developed in his legs while exercising (we confirmed this during the main Q&A), but had also heard that salt could help too. The sodium in salt is actually physiologically paired with potassium throughout the body. The only thing is, unlike with potassium which banana-haters might actually run low on, as unhealthy Americans we are never deficient in sodium thanks to our over-consumption of salty foods.

So, could sodium deficiency cause the cramps? Yes. Is that likely? Not really. Try a banana and some more water first. The man was incredibly thankful for both our time in general and for my extra effort to answer his question (and he told me so!). It was the first time I got to go out of the way for a patient - the first time I made a connection and established a professional trust with someone.

This is why I went into medicine. If I had to sum it up in a sentence, I might fall back on the application staple ("I love science and want to help people."), but it's something more than that. Something harder to describe but exceedingly more beautiful.

Tuesday, October 8, 2013

WILTIMS #45: ER pros and cons, developmental knee alignment

Today we spent an hour watching our anatomy professors butt. Specifically we were watching him demonstrate the action of the gluteus muscles during various actions.

This evening was the first emergency medicine interest group meeting, during which an EM doctor and NYMC alumnus gave a presentation on the specialty. Pretty much confirmed my understanding. Pros: hourly shifts (never on call), can move anywhere with little notice, world's best diagnosticians. Cons: bad hours (open 24/7), no long-term patient interactions, have to give the most interesting cases to other specialists, generally not dealing with the most pleasant patients (especially at 2am on Friday).

TIL: Long term steroid treatment, such as that for Crohn's disease can obliterate the artery to the head of the femur, resulting in necrosis of the bone and requiring hip replacement surgery.

The normal growth of the legs includes periods of bow-leggedness and knocked-knees. From birth to about 1½ years the leg bones are very pliable, bear little weight and are bowed outward. They grow straight for about 6 months as the child is learning to walk, but then a growth spurt hits and forces the knees closer together. This is corrected fairly quickly resulting in properly aligned legs. 

WILTIMS #44: Embroidery saves the day?

Last night I hosted an applicant to our medical school who had an interview today. The whole experience just reminded me how happy I am to be past that stage - a needed reminder with another test looming.

My day started out with some Nobel Prize trivia following the announcement of this year's Prize in Medicine/Physiology (for vesicular cell trafficking incidentally). Our anatomy professor told us the complicated tale of Alexis Carrel, 1912 Nobel Laureate in Medicine. Carrel pioneered the first vascular repairs (sewing back together torn blood vessels), in part using the technique of embroiderers from the Lyon area of France.

The problem with suturing blood vessels up to that point was that the standard technique called for clamping off both sides of the vessel and then trying to stitch first the top and then the bottom of the now flattened vessels walls. The reason this didn't work is that vessel walls are incredibly thin and fragile. The clamps irrevocably damaged the tissue and the surgeons couldn't suture one side without nicking the other, causing even more damage. The answer came in the form of the triangulation stitch, a method borrowed from sewers (as in one that sews, not one that collects feces) of fine silk tubes. They would use three small stitches placed equidistant around the tube to pull the tube taut, forming three flat sew-able surfaces that, when relaxed, formed a complete circle.

This technique made many now common surgeries and the entire field of transplantation possible, saving countless live. So why did I sale Carrel's story was complicated? His best friend was Charles Lindbergh, the famous aviator and later Nazi sympathizer. Together they invented the first perfusion pump, the precursor to the artificial heart, again saving untold lives. However, they were both outspoken supporters of eugenics and Carrel later moved back to France during the German occupation of WWII to work in high level scientific positions in the Vichy government. Thus, these were men with murky legacies, to say the least.

TIL: A good way to find reflexes on a seemingly reflex-less patient is to ask them to lock their hands and pull against their own strength as hard as they can. While the patient is distracted, you can whack them with the hammer with renewed success.

Saturday, October 5, 2013

Study Aid #4

My stab at drawing all the muscles of the back in one diagram (not recommended). Simple, yes?

WILTIMS #43: Eeeeeeeeeeeee!

There's not much to report from today as we only has two lab sessions (one in histology, one in anatomy). The highlight of which was the "degloving" of a hand, to gain access to the ligaments, nerves and blood vessels beneath. Not an easy or cringe-less process, to be sure.

TIL: Never give a vasoconstrictor with local anesthesia in the fingers. Vasoconstrictors are drugs that cause the tightening of blood vessels and they are often given with local anesthesia to help them stay in the patient's blood circulation longer. The problem with the fingers is that they only get blood and nutrients from two tiny vessels and the administration of a vasoconstrictor will cut off blood to the entire finger. If not corrected quickly, the tissue will die and the patient could lose the finger.

Mini-Me and Dr. Evil
Muscles that control the pinky finger are named the digiti minimi, good words to know for when you're stuck with all those "I"s in Scrabble. Relatedly, the writers of Austin Powers 2 were either breathtakingly witty, or fantastically lucky with their choice of character names. Dr. Evil's half-scale clone is called Mini-Me. Though you might think this is merely a play on "Miniature Me," note that a minimi is a Belgian machine gun and that the extensor digiti minimi muscle is responsible for the iconic gesture seen in the accompanying picture.

The last tidbit that I learned today, came from a family member who had a recent brush with the medical field. A laminectomy, the removal of some or all of the back-most (or laminar) surface of one or more vertebrae, can be an effective late stage treatment for spinal stenosis, a narrowing of the spinal column that puts pressure on the spinal cord. Fascinating if unpleasant stuff. Get well soon!

Friday, October 4, 2013

WILTIMS #42: A blessed nerve injury

At one point today, our head anatomy professor was up on a table on all fours with oven mitts on his hands and feet. Learning anatomical development is weird.

There was a fun point today where for the first time I learned something that someone had asked me about in the past few years of pre-med purgatory. They had a bump on their wrist and came to me because I was "the medical person" and I had no idea what it was. We made a solid guess based off some internet perusing and forgot about it. Today we covered synovial cysts of the wrist, one of which was in fact the cause of my friend's bump. It's a totally benign condition that can be resolved by, no joke, smacking the wrist really hard to pop the cyst.

TIL: The "anatomical snuff box" (pictured on the upper right on the beautiful hand of yours truly) is a groove on the forearm that received its name by victorian era snuff sniffers who found it a convenient to spot to place snuff while they put away their snuff box.

Injuries to the radial nerve can cause the arm and wrist to assume what's called the "waiter's tip position" (seen on the left).

A median nerve injury can be identified by asking the patient to try to make a fist and then looking for the "hand of benediction" (No, JPII didn't have a nerve injury; he is doing the namesake sign of benediction that happens to perfectly mimic the nerve condition).

Wednesday, October 2, 2013

WILTIMS #41: Uno!

We started today being bombarded with the intricacies of the arm and forearm. For some semantic reason we are calling the upper arm simply the arm. This made for some confusing statements such as, "The median and ulnar nerves don't innervate anything in the arm; instead, they travel all the way through the arm and innervate the muscles of the forearm."

We had to change into our white coats and professional attire for the second half of the day as we had the privilege of watching a sample patient interview by one of our professors of an actual patient. The patient was a kick in the pants and even though we were packed like sweaty alabaster sardines, we really enjoyed the lecture. Afterwards we broke up into smaller groups in the modular rooms upstairs to discuss the process of interviewing patients, specifically in regard to showing empathy.

I had a nice pair of experiences that I think beautifully show both my inexperience and potential. We were asked what we would say to a patient who we had just informed that she had mononucleosis. My first response was,
What's mononucleosis!? I feel like I know this... Is it a cancer? What has one nucleus? Who let me into this school anyway?
Meanwhile, one of my classmates responds by saying that she'd ask about the patient's medical history and try to find out where she contracted it from. I'm still beating myself up:
How does everyone else know what this is!? We don't take pathology until next year!
Then a second classmate takes a stab at it, saying that he'd want to find out what treatments are available and relay that to the patient since mono is treatable.
MONO!? How did I not know that mononucleosis is the full name for mono! Of course this disease isn't named the equivalent of "uno."
Hey wait, I know the answer to this and it nothing to do with the disease!
"Anyone else?" my professor asked, clearly frustrated at the direction my fellow classmates had headed with the question.

I raise my hand. "Well, I think I would first try to reassure her that..."

"THANK YOU!" The professor abruptly cuts me off. "Reassurance is exactly the word I was going for." She goes on to explain how to best reassure patients after giving hard diagnoses, while I start to feel better about my mono mental lapse.

TIL: In the loosely transcribed words of our example patient: "There are only two people you don't lie to - your doctor and your priest... and your mom!" Noted.

WILTIMS #40: Confidence, Schlemm and gravity

I forgot to mention yesterday that I poked around the hospital for the first time like a total dork. I wanted to try out the Au Bon Pain café in the hospital because I'm hosting an interviewee this Sunday and it's one of the few walkable dinner options I can offer (and I was tired and lazy - don't judge). After eating my surprisingly tasty sandwich, I decided to see how far my student ID badge would get me and explore the hospital a bit. As with any place that you probably shouldn't be, the key to exploring is to do it with blind confidence.
"Yes, I meant to go down this abandoned hallway! I'm inspecting the... uh, light switches. Yep we're all good here!" [walks hastily back the way he came]
Hopefully by the time I actually need to be in this hospital, I will be a smidge less lost than some of my classmates.

TIL: The canal of Schlemm is fun to say. I'm going to put it in the same category as the epiploic foramen of Winslow and the ampulla of Vater. Besides reveling in its euphonious name, I also learned it's location and function (apparently I learned the word euphony as well).

Schlemm's canal is essentially a drainage duct for the aqueous humor (gooey stuff) in the eye. If the eye is damaged and scar tissue ends up in the fluid, that tissue can collect in and block the canal, leading to an elevated intraocular pressure which is the most important precursor for the development of glaucoma. For anyone who's ever been to an optometrist, this is what they are checking for when they blow that puff of air at your eyes.

Our random sports fact for the day: when you see male gymnasts in the Olympics doing the Iron Cross skill (pictured on the right), the one muscle in their amazingly cut torso/upper extremities that they aren't using is the deltoid. The deltoid is used to abduct the arm (move it away from the torso), but gravity is doing all that work for the gymnast. He is in fact using all the muscles that normally oppose the motion of the deltoid (such as the trapezius and latissimus dorsi) while the deltoid, though bunched up from the position of the arms, lazily sits there waiting for gravity to stop stealing its thunder. Stupid gravity.

Tuesday, October 1, 2013

WILTIMS #39: Thymic elegance

Ouch. That test hurt. But the 5-exam week of hell is over! Huzzah!

There is something I wanted to share with you guys that I didn't learn today, but was really impressed with while studying. The thymus is a primary lymphoid tissue, meaning it's a site for blood cell development. Specifically, the thymus is responsible for the maturation of T-lymphocytes. You may remember from your high school biology class (it's ok if you don't) that there are "helper" T-cells and "killer" T-cells. These cells are part of the body's adaptive immune system, which recognizes a threat (from bacteria/viruses/fungi) and both attacks it and remembers it for future reference.

The nifty part is that the discerning thymus essentially weeds out both the lazy and homicidal T-cells before releasing the mature, level-headed ones into the body. It does this in two steps: First, it offers up some practice targets that it would like the T-cells to latch onto. If the cells don't bite, they're killed off. The survivors are then released to the second test area. The thymus again offers up targets, but there's a catch: this time the targets are actually pieces of good structures from within the body. If the T-cells go for these, then they are showing autoimmune capabilities and are also killed. This way only the cells that reliably target antigens are allowed to patrol the body. Elegant huh?

I could not for the life of me find a good diagram of this process, so I whipped this up for you:
TIL: Fascia adherens is found in the intercalated discs of cardiac muscle. This was on my first test today and I had completely forgotten it. Luckily, after looking it up during lunch, I got a different question about it right on test number two.