We finished our cadaver-based anatomy course in the middle of February with head/neck anatomy, and then transitioned over to a neuroanatomy course. One would think that physically studying the brain would be of great interest considering my goal, but there’s something about it which just isn’t “exciting” like finding muscles, tendons, vessels, etc. Maybe it’s because the overwhelming majority of the brain’s elegance cannot be visualized? Maybe it’s because there aren’t any cool lever systems which attest to the body’s incredible mechanical design?

The infectious disease course has also spanned two blocks (four months), and just like anatomy, there’s a lot of memorization; however, unlike the former, there’s very little application until we get to clinicals. Initially, much of my time went into memorizing the Latin-root-heavy terms of anatomy, but I immediately applied that knowledge in locating structures during lab. Who cares if P. aeruginosa causes otitis externa or E. histolytica can cause bloody diarrhea? I won’t really remember any of this stuff until I see patients.

…but I guess that’s how medical school goes.

Watching NBA games over the weekend obviously counts as studying the nervous system.

With surgery at the forefront of my career goals, my inclination towards studying anatomy was rather natural. My cadaver was undoubtedly the single greatest “professor” I’ve had to date in advancing this goal.

I remember a particular experience early in medical school. A week before the first block exam, I decided to visit the anatomy lab in the early morning hours to review for the practical. It was quiet. The sound of classical music resonating through the lab was partly muffled by circulating air. At first, being surrounded by so many dead bodies was a bit daunting. Heck, I’d been a medical student for just over a month at the time.

Opening the cadaver tank and flipping through the dissector manual, I realized how precious this time was. It’s almost as if she was providing a walkthrough of the brachial plexus, what to watch out for, why her extensor and flexor compartments were arranged as they are, etc. Showcasing the elegance of her body initiated my appreciation for how incredible human anatomy really is.

This was also the same day I realized time moves faster in the anatomy lab than anywhere else I routinely visit. Seriously, one doesn’t realize just how many hours they burn in that lab until their legs start locking.

I just wish there was some way to express to her how much she has helped me as a teacher. I’ve given nothing in return, not even a word of thanks, yet she provided me with one of the most memorable and applicable experiences I’ll ever have in my medical training.

Thanks to her, my experiences in gross anatomy lab can be summarized in one word – dynamic.

We have 31 pairs of spinal nerves emerging from the spinal cord coming out at every vertebral level. A spinal nerve is comprised of ventral motor fibers and dorsal sensory fibers, thereby making it a mixed nerve. 14 of the aforementioned 31 pairs (from the thoracolumbar T1 – L2 region) have additional sympathetic fibers added to the mixed nerve from the spinal cord.

The sympathetic chains run on both sides of the spinal cord from the base of the skull to the coccyx (keep in mind that the spinal cord only runs from the base of the skull to around L1/L2). One can think of the spinal cord as a distribution center of the brain. Similarly, the sympathetic chains are distribution centers for the specific sympathetic region of the spinal cord (T1 – L2). This is how, for example, we get sympathetic innervation in our upper limbs to control things like sweating and vessel constriction even though the brachial plexus is above the sympathetic region (C5 – T1).

Rami communicans are the “bridges” between the spinal cord and sympathetic chain. All 33 pairs of spinal nerves receive gray (unmyelinated) rami communicans from the sympathetic chain, but only the spinal nerves in the thoracolumbar, sympathetic region (T1 – L2) give off white rami communicans (myelinated) to the sympathetic chain. This is precisely why we don’t have white rami communicans in the head/neck region as well as the pelvic region.

Splanchnic nerves (myelinated) are those which come from the spinal cord, pass through the sympathetic chain (they do NOT synapse there like the rami communicans), and proceed to synapse elsewhere. It should be noted that splanchnic nerves carry sympathetic fibers except for pelvic splanchnics which are parasympathetic.

As a side note, I’ve also found that in preserved cadavers, the sympathetic chain seems to be “stuck” along the sides of the spinal column while splanchnics tend to be the loose, nerve-like structures adjacent to them.

That’s the end of my lesson for today. I know it’s pretty dense and potentially confusing, so feel free to leave questions!

After carefully completing the separation, my tankmates proceeded to clear out some debris from the sinuses and around the soft tissues. We noted the terminal opening of the Eustachian tube in the nasopharynx, the epiglottis, the little ball thing hanging at the back of the throat (uvula), and went over where various tonsils are located.

When we think of “sinus”, often times our attention is directed to the region immediately behind the nose, but it was amazing to see the air-filled paranasal sinus cavities above and below the eye. At first, I guess it’s “gross” to imagine that ear fluid, mucus from the nasal cavity, and saliva from the oral cavity can all travel into the pharynx together, but learning about how these sinuses interplay with the nasal cavity in drainage events is more fascinating then I would’ve ever thought.

On another note, it’s a bit depressing to see anatomy lab approach its conclusion. I’ve learned more from my cadaver than any other “teacher” I’ve ever had, but have never had the opportunity to reciprocate my thankfulness to her. I suppose that in the coming years as I mature as a medical student and *hopefully* embark on my neurosurgery residency, I’ll remember her as the sole reason for the bedrock of my anatomy knowledge.

When you think about it, the neck incorporates a lot of important structures. Our trachea, esophagus, spinal cord, and major blood vessels are all contained in a cylindrical tube which has been fitted with all the necessary muscles to also provide an incredible range of motion.

Enter the hyoid bone: the only bone in the body which doesn’t articulate with another bone. Pretty cool since it’s just “floating” in the anterior neck. It’s also a focal point in the naming conventions for a lot of muscles in the area (ie, sternohyoid, thyrohyoid, stylohyoid, hyoglossus, mylohyoid, and geniohyoid).

Put the scalpel down, or else you’re guaranteed to cut one of the tiny branches of the external carotid artery. I remember missing the first lecture on neck anatomy. I downloaded the PowerPoint, started going through the content, and came across a slide with all the major branches. My first thought: “There’s no way we’ll have to know these.” Come to find out… we do. And a whole lot more. Superior thoracic, ascending pharyngeal, lingual, facial, occipital, posterior auricular, marginal mandibular, and superficial temporal. *Whew*

Also, who would’ve thought that my favorite facial muscle (sternocleidomastoideus) and favorite muscle overall (trapezius) would be innervated by the same nerve (cranial nerve XI – the spinal accessory nerve)? Heh, I guess that makes it my favorite nerve by default.

Can’t wait till we get to look at the actual brain next block, but it’s incredible how elegant the neurovasculature and musculature of the head and neck have been so far. Looking forward to tomorrow’s lab!

Major’s Bookstore is having a liquidation sale since they’re closing down. I was there yesterday to purchase my immunology book and noticed how all the inventory had been brought to the front (including a full skeleton and a skull replica). I reluctantly asked the cashier if the skull was for sale, and she quoted me a $10 price on the spot (in other words… an absolute steal). Should have asked how much she would sell the full skeleton for. Now my only dilemma is what to name it!

Today was also an epic fail for me. I could see myself following incorrect thought processes. My rationalizations were all backwards. If everyone went right, I went left (and was wrong for doing so). I couldn’t even tell a freakin’ apple apart from a pear! Everyone has off days, but to be this unfocused this early in the block is dangerous territory.

We were polled yesterday about how we learn best (visual, auditory, or active) and to what extent we focus on details. To my surprise, only a very small fraction of people admitted to being auditory learners. I’ve always learned better this way. It’s the fundamental reason why I can’t work in groups. Learning by listening tends to be faster, more integrated, and more relevant (highlighting the important points) whereas learning in groups tends to be more inefficient. Consequently, lectures which are considered boring by my peers are still the best option for me.

I just hope tomorrow is a better day.

By virtue of having a female cadaver, we could not partake in dissecting the male reproductive structures (which are way more complicated than a female’s), but my classmates with male cadavers have been excellent teachers in showcasing what they’ve dissected.

The perineum is a pretty nifty area. Without it, the contents of one’s abdomen would quite literally “fall out” from between their legs. That could be pretty bad.

It’s kind of exciting knowing that we’ve practically finished dissecting the entire human body (except the head/neck region). Looking back, I’ve learned hundreds of new clinical correlations, muscles, bones, and ligaments… many of which I will never need to know again. With my aim at neurosurgery, block 4′s anatomy will be a lot more interesting and relevant to me. But till then, it’s time to master the abdominal/perineal region.

Wow, and now as I reread this post, I’ve realized how disconnected the content is. Oh well.

My tank has been exploring the wonders of the gastrointestinal tract over the last few weeks. We’ve gone through the abdominal wall, taken a look at the surface anatomy of the liver, explored the stomach, and tracked the course of the small/large intestines. Along the way, we’ve also run into the vermiform appendix, extensive neurovasculature of the GI tract, and some reproductive structures (namely the uterus, ovaries, scrotum, and spermatic cord).

Going into medical school, I was aware of how complicated (yet elegant) the digestive system is from a textbook standpoint, but actually seeing these structures is something totally different. I imagined the small intestine to be a tube-like structure jumbled haphazardly between the large intestine. Though I was somewhat accurate, there’s so much more! You’ve got a huge “mesentery” which runs intimately with the intestines. Your enteric nervous system has just as many neurons as your entire spinal cord (~100 million) and can function independently of the central nervous system. Pretty neat stuff!

The further we get into the dissection, the more I realize how true the statement one of our professors made during the first week of school really is – “your cadaver is your best teacher.” Flipping through my USMLE prep book and anatomy atlas, I’ve come to the realization that so many of the finer details I’ve learned would not have been possible without my donor. She has spent countless hours teaching me about her most inner workings, and I’ve spent countless hours trying to retain everything. Now that’s teamwork for you.

For many of us, this workshop was the first time we had actually worked with unembalmed cadavers. Why did we use them? For the simple fact that their anatomy behaves more like a living person. What’s the point of learning how to suture on an embalmed cadaver when “living” skin has far more elasticity and tensile strength?

At every cadaver, there were three TA’s (one teaching suturing, one chest tubes, and one intubation). We had thirty minutes for each skill, and then rotated at the same cadaver to the next skill.

Let me be the first to tell you that no matter what you’ve seen on TV regarding intubation… it’s pretty difficult. It took me two tries to finally get it, but I’m glad I had the opportunity to mess up.

1. Does all your equipment work properly?
2. Is the patient’s head in the “sniffing” position?
3. Use your dominant hand to open the patient’s mouth using the “snapping motion.”
4. Start from the right side of the patient’s tongue and sweep to the left as you insert the laryngoscope?
5. How do you know that you’re in the trachea and not the esophagus?
6. Inflate the balloon and auscultate for equal breath sounds.

Suturing was really fun too! At this point, I think it just takes a lot of practice to improve a.) technique and b.) speed, but I feel that there’s still plenty of time for that.

Overall, the workshop was really impressive. Everything was set up, the TA’s were fantastic and extremely helpful, and I learned a lot!