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Light warning: While this post does not contain any of the explicit descriptions of dissection featured in the last two entries, it does, to borrow a phrase from This American Life, acknowledge the existence of cadavers and the events of anatomy lab. Also, my perception of acceptable dinnertime conversation remains off center, so please take that into account as you read this entry.

There is a special kind of fear struck into the hearts of medical students at the mention of the anatomical practical exam. Although this frustrating ritual of medical education has decreased in importance in recent years, it is still an important rite of passage for medical students. I call it a rite of passage because I question its direct vital importance to the learning of anatomy, despite feeling that the actual dissection of cadavers has been immensely helpful in my medical education. To be honest, I think the practical exam exists mostly as a means of motivating us to devote the proper time and attention to studying the cadavers, rather than being an accurate means of testing our mastery of anatomy.

At our school, the exams are held on a designated Friday afternoon. The class is divided up into groups, and each group (ranging from 30 to 50 students depending on the number of questions/stations available) is assigned a time. We are to

Seriously though, who even owns a clipboard these days?

bring a clipboard and a writing tool. Those who wish can change into scrubs, but no safety gear is required.

We arrive in the hallway in front of the lab, drop off our backpacks in the locker room, and stand around nervously. Eventually the anatomy professor emerges and hands us all pieces of paper with 60 blank lines. She instructs us to write nothing other than our names on the papers, but as soon as we enter the lab we can scribble whatever notes we wish. Once everyone is ready we file into the lab through the women’s locker room.

One of the lab instructors likes to spice things up. As we enter the lab there are jock jams blaring from an old boom box, and he’s wearing a bright orange baseball cap backwards as he jumps up and down. The man is in his late 50s at least, with a bushy white beard and an awkward, soft-spoken manner, so the first time I saw this I burst into nervous laughter. The other lab instructors and fourth-year TAs are also standing around in their scrubs and white coats, smiling encouragingly at our obvious anxiety.

We each head to a station. There are a number of cadavers, several models, and a number of computer screens with X-rays or CT images. Each cadaver has two stations, one on each side. Each station has a pin, an arrow or a string tied around a structure, and there is an index card nearby with a question or an instruction. There are several orange chairs positioned around the room as rest stations.

One of the professors gives us our instructions. They are the same every time: “Look at the number for your station and circle it. Be sure to write your first answer on that line. Don’t write your first answer on line one unless you are at station one. Check which number you are on frequently. You will have one minute at each station and there are a certain number of rest stations. Stay in order. Do not skip stations. If you get lost ask for help. If you do not know what structure is indicated, ask an instructor. If you ask anything else the answer will be, ‘use your best judgement.’” He says this last part with a sympathetic smile because he knows this is the most frustrating answer in the universe and the only way for the teachers to get through this exam in one piece.

Then he offers the usual advice: “First get oriented: are you on the front or the back? Which way is the head? Then identify the indicated structure. Next, read the card at your station and write the appropriate answer on the blank that corresponds to that station. Answer only the question on the card. Not all of the cards say ‘identify.’”

There are about eight televisions, the big boxy ones on metal shelves hanging from the ceiling like in public school classrooms. The screens are blue with a number in the center. When the instructor says go, the number starts at 59 and counts down silently to zero like you’re on a game show. Whenever the number hits zero, the lab instructor yells some variety of “rotate!” or “move!”

The instruction to “get oriented” seems obvious, but the cadavers are well draped. Mostly this is to protect them from drying out, a major problem, it turns out, once you remove a person’s skin. There is also a fair amount of obscuring done for the sake of difficulty. You cannot see faces, genitalia, hands or feet unless that structure is specifically being pointed out. The cadavers are also largely sans skin, so all the usual orientation clues are missing.

We are not allowed to touch anything either, which is frustrating given than all of our studying has required us to find the structures by digging them out for ourselves. If I’m used to locating the musculocutanous nerve by finding its origin at the brachial plexus, I had better hope they have positioned the cadaver so you can see the brachial plexus when they pin that nerve. It’s also harder to distinguish structures like arteries and nerves when you can’t feel to see if they are hollow or move the drape back just a bit to see if you can see what branches it gives off. I end up twisting and contorting myself trying to peer into body cavities without blocking the light, my nose and hair getting dangerously close to formaldehyde-soaked fabric.

One minute, as it turns out, is precisely enough time to settle on an immediate answer and then second guess yourself. In some ways it reminds me of physics tests from postbac, where it was better not to even try to check your work if you managed to stumble upon an answer. Just keep moving and don’t look back.

Spelling doesn’t count on these exams, which is good because the words ophthalmic and infundibulum will never cease to send my brain and fingers into spams without a spell check. We are strictly forbidden from abbreviations, however, which I find intriguing given how pervasive abbreviated language is in medicine and our school curriculum. (In two labs

Look at that judgmental expression. As if he could spell pterygopalatine fossa off the top if his head.

of brain anatomy alone we’ve already learned about PICA, and AICA, SCA, PCA, MCA and ACA.) They will also, apparently, take off for lack of specificity; it is the styloid process of the ulna, not the styloid of the ulna. There are also no points for being technically correct either; the identity of one x-ray structure was the adductor tubercle, and the fact that the arrow was also pointing to the medial condyle of the femur did not mean that was an acceptable answer.

Once the exam is over, we turn in our tests, file out, and, usually, head off to study for the written exam. By the time our tests are graded and accessible, we are usually well past the point of real concern. As good or as bad as it feels to see where you ultimately fall on the curve, the skills being tested in anatomy practicals don’t seem to correlate to anything particularly useful in medicine. “When am I ever going to have to diagnose someone without asking any questions or touching them?” one of my friends pointed out.

I will say, in defense of the anatomy practical, that studying for something “hands on” is completely different from studying for a written test. I could have pored over dozens of textbooks and memorized every division of every artery and nerve and never have really understood how it all fits together as well as I did studying it within a body. Some of my esteemed colleagues may disagree with me on this point, but I would argue that, although the exam may not have realistically assessed my understanding of anatomy, it was a powerful motivating force. I doubt that I would have ever learned so much or so thoroughly had that impending exam not driven me back to lab so many afternoons.

Warning: This is another graphic dissection-related post and possibly contains some of the grossest descriptions yet. I also might ruin oranges, cottage cheese and s’mores for you forever. Read at your own risk.

Do you know what you get when you send out an email asking medical students if they would like to give up an afternoon to assist with an optional brain removal dissection? A lab full of medical students wielding bone saws and chisels.

Where do we cut? The top part, right?

(If you’re already rethinking your commitment to reading this post, the back button should be at the upper lefthand corner of your screen.)

We’ve started our unit on the central nervous system, which means I am in full neuro-nerd mode. (Another student called me that earlier today and I like the alliteration so well I decided to keep it.) We’re not actually doing a lot of cutting in our dissections for this unit, but the brains did need to be retrieved from their usual location. The idea was to use all of the brains from our cadavers along with a few supplemental brains* from surgical pathology so that we won’t have to alternate dissection groups like we have been doing with our cadavers.

Here is how to remove a brain:

First you have to remove the skin of the cranium. You do this by making an incision from between the eyes to the back of the head and from one ear to the other and then peeling back the flaps. This was a bit more intimate than I was expecting, given that we had covered the face of our cadaver on the first day of lab and had not uncovered it since. The rest of his body was devoid of skin except for the soles of his feet and the backs of his hands. In many ways our cadaver had ceased to feel like something that had once been a person. Uncovering his face and making that first incision between his eyes was different. I have a hard time attaching an emotion to it–I didn’t find it sad or gross or creepy–but I noticed it.

Peeling the skin off the bone of the scalp is like peeling an orange. It comes away with a good solid tug and makes that same soft unsticking sound The deep fascia underneath even looks like the white inner rind. Underneath, the top of the skull looks just like every skull you’ve ever seen, off-white and smooth. The temporalis muscle on each side (the thing that tightens up at your temple when you clench your teeth) is the only non-boney landmark. We reflected them back as well so that we would only be sawing through bone.

The striker saws have small, semi-circular blades. They cut through the bone pretty easily, but they are just unwieldy enough that it’s hard to judge how deep you’re going. The goal is not to saw through the entire bone, but rather a few millimeters deep and then to crack the rest of the way through with a chisel and hammer. Halfway through this process you have to flip your cadaver over to make a complete circle around the head. Then you flip it onto its back and saw across the top like a headband.

The bone saws kick up a lot of bone dust and the friction creates a bit of smoke. It smelled to me like burning marshmallows. (No, I wasn’t hungry during this dissection, I swear! I reasoned it out with another student later: marshmallows and bones are both made of gelatin, after all.)

Some of the cadaver brains weren’t properly embalmed, which brought a whole new meaning to the phrase “my brain is mush.” They were the consistency of cottage cheese and oozed out of the new opening in the skull. Even the anatomy professor was grossed out. Those brains were left in their respective cadavers with several layers of wrapping around them both.

Our brain was well-preserved. The skull cap made a ripping/popping noise as it came free: the sound of the dura mater (the tough, protective coating of the brain) pulling free of the bone. Then we sawed through the occipital bone at the back of the head so that the spinal cord could be severed.

Even then, there was a lot more to be disconnected: the roots of the dura mater, the vessels that carry blood into the brain, all of the cranial nerves (there are twelve pairs.) Then we were done, and the brain came free like it was never all that attached in the first place. What, all that work just for me?

Strange to think that the object I was cradling carefully in two hands (not-dropping a brain on the first day was pretty high on my to-do list) had held all of the thoughts, the memories, most of the personality of the person it once belonged to. It is dead now, fixed and quiet, but I wonder if someday we might be able to look at all of the connections that existed and see something of the thoughts that passed through it once. Or maybe we’ll discover that to be something completely unknowable, something greater than the sum of its parts. It sort of hurts my own brain to contemplate. In a good way.

Ze Brain

*Every time I say the phrase “supplemental brain” I want to make a joke about borrowing one for the next exam. I know, it’s terrible, but I just can’t resist.

Warning: This post concerns my experiences in cadaver dissection. At this point in my medical training, I can casually chat about what went on in lab over dinner and not think anything of it. You, on the other hand, may have slightly conventional standards, and might find it a bit graphic. Please take that under advisement before continuing. 

Ready? Let's go.

Ready? Let’s go.

 

It’s a relief learning you are not the only person who finds skinning and separating out muscles on a cadaver oddly satisfying. It’s not really something you can bring up in polite company, but when a group of med students are sitting around the lunch table waiting nervously for their first practical exam, these sorts of things come up.

We’ve just finished our third week of lab and our cadavers are now largely sans skin. Removing it is a time-consuming process; skin and the fat underlying it are rather firmly fixed to the fascia and muscle below. The technique involves making two incisions to create a corner flap of skin, carefully going deeper layer by layer until you can see the red of the muscle or the silvery stripes of tendons. Then you grasp your flap (careful to not grasp any of the muscle tissue along with it) and pull back hard, like you could peel it right off. Then you scrape gently at the wisps of fascia between the fat and the skin with your scalpel, slowly detaching them and peeling away the skin. The idea is not to go so deep at to cut through the muscle and also to remove enough of the fat and fascia that you can see the muscles and structures below.

When it is going well it is not unlike managing to pull the entire peel of an orange in one piece. Or finally getting the long red piece in Tetris you’ve been waiting for the whole game.

When it isn’t going well, you can’t tell muscle from fascia from tendon from fat and you kind of want to start throwing your tools around the room.

Separating the muscles is similar, although you usually don’t even need a scalpel. You run your fingers or a probe through the fascia surrounding the muscle groups, pulling it apart like spiderwebs.

Nerves and arteries are more frustrating. They are usually bound up in a lot of fascia, but delicate enough that you want to avoid ripping through with your hands or slicing through with the scalpel. They also often look enough like bits of fascia (especially the smaller nerves) that you might not even notice them at first.

Going to lab has utterly revolutionized our schedule as medical students. Instead of spending four hours in a classroom listening to an array of lectures, we spend three or four hours on our feet, actively working through a lab. In some ways it’s a break for our brains; the concentration required to decide if you’re in a muscle or still on the plane above it is completely different than that required to memorize innervations or artery bifurcations. Most of the lab is physical work with breaks to try to identify structures. The time flies by and there is absolutely no risk of falling asleep.

We’re also divided into two groups per cadaver. One day my group might dissect the abdomen, the next day the other group will examine our work and dissect the front of the thigh. Which means a whole day off, at least once a week. After the non-stop slog of Monday through Friday 8 a.m. to 12 p.m. classes in the fall, this is like a dream come true.

That isn’t to say anatomy is a walk in the park. Some things in medical school are difficult simply by virtue of the fact that they require decades of experience to really master. Reading x-rays for example, or recognizing histology slides. I can memorize the nerve innervation for every muscle in the lower extremity, but learning to distinguish artery from nerve at a glance is an art. Sometimes even the professors aren’t quite sure what they’re looking at. This is the part of medicine that takes the most practice and is the hardest to explain how to do. It is also the part of medicine that feels the most like being a doctor.

I have been waiting to write about cadaver lab since I started this blog. It is such a defining piece of medical education and is surrounded by so much history and mythology that it is hard to imagine where the reality lies. Cutting open dead bodies is the stuff of horror films or indelicate humor. The idea that one body will become my template for understanding how humans work inside is creepy and exciting all at once. I am already intensely curious about the body I will be working on. Will it be a male or a female? How did she die? What kind of life did he  have? What made her decide to donate her body to us?

The school takes cadaver lab very seriously. We have several classes designed to address the implications behind dissection. At the end of the unit there is a memorial service for all the cadavers. We are warned to treat them like patients.

Our first assignment with the cadavers will be to wash and shave them. We have very specific step-by-step instructions on how to go about this. They are curiously impersonal and somewhat vague. For example, if your cadaver is lying face down you are to turn it over onto its back. And yet I have no practical idea of how one would efficiently go about this. There are certainly enough of us to manage the weight, but the logistics of arms and heads and the immediacy of lifting a dead body for the first time seem perilous.

If necessary, we are to trim and then shave the hair on the head, armpits and pubic region of our cadaver. I am interested as to how a group of nine people decides who is responsible for shaving the genitals of its cadaver. Certainly we are all going to have to get extremely familiar with uncomfortable areas of the body, but I will confess I am a little intimidated. I can’t even figure out if the fact that our cadaver is dead makes it better or worse.

I am excited to start anatomy in the same way I get excited at the top of a roller coaster. Part of me is thinking, “At last the thing I have been waiting for,” while the other part is thinking, “Um…maybe this wasn’t such a great idea.” I expect that, also like with roller coasters, I will be glad I did it in the end.

Please Note: The following post contains some slightly disturbing imagery with very little context. I am currently seeking out further information, and will update as soon as I know anything.

There is a hall in the cadaver lab of the medical school that is lined with glass cases. Within the class cases are rows and rows of glass jars and in the glass jars are fetuses.

The doctor who was guiding our post-bac field trip to cadaver lab mentioned it in passing as the more organized part of the trip was coming to a close. A few other students and I wandered back to see.

There did not appear to be any particular organization to the collection. Some jars had labels with the size of the embryo, the date it had been preserved, or some disorder that had been observed. “Clubbed foot,” read one, the deformity readily obvious. Other had labels that seemed pseudo-scientific; “siamese twins” or, inexplicably, “monster.”

Most of the jars had no labels at all and seemed like the sort of collection one might find in the basement of an old farm house a few days before jamming season. They ranged in shapes and sizes and many had markings from their previous life as food containers. A Planters Peanut jar was located, as was one that used to hold mayonnaise. Some had blank labels or were turned away from view.

One student suggested that “monster” may have been a legitimate medical term at some point; the general sense I had was that these specimens were not recent. The few labels that did exist were faded and the lettering had clearly been done on a typewriter. None of them had the look of research tools that had been accessed recently.

Eventually one of the postbacs gave voice to what we all must have been thinking. “This reminds me of an exhibit at a freak show or a scene from a movie.”

“You know in Aliens when they’re trying to get Signorney Weaver to mate with one of the aliens and they show the room of failed experiments?” someone else commented. There was a murmur of agreement in the group.

“But isn’t there something wrong with that? That this is reminding us of a sci fi movie?”

No one had an answer for that. Vaguely unsettled we returned to the main room and focused our attention on the less creepy prospect of examining fully-formed human remains.