Dissecting and Drawing the Forearm: Anatomical Illustration for the Classroom

ABSTRACT:

Flexor Compartment of Distal Forearm layer 3
Flexor Compartment of Distal Forearm layer 3

The human hand is challenging to study, due to having many narrow vessels and tendons packed together in a small space. Because of this, it is useful to have clear diagrams showing just a few structures at a time. From February to mid-March 2017, a human distal forearm was dissected and used as a model for six drawings in the style of a traditional anatomical atlas. These images are meant to be teaching tools for helping students identify structures, just like a professionally made atlas. During the dissection process, rough pencil sketches were made in the lab as new structures were exposed. Later, these sketches were redrawn in full color with colored pencil. Anatomical illustration could be an educational activity for students: by trying to draw diagrams clear enough for others to understand, students would retain more information and improve their communication skills.

DISSECTION:

In Dr. Olson’s basic gross anatomy course at NIU, the undergraduates often use atlases to help identify countless tiny structures. These atlases introduce students to the art of anatomical illustration, which has roots as far back as the Renaissance. The hand is an ideal subject for an atlas because it has so many tendons, vessels, and bones that can be difficult to keep track of, so it would be helpful to have clear diagrams of these parts. The hand is also more “relatable” relative to internal organs; hands are frequently used for nonverbal communication. People depend on their hands to do so many tasks everyday but rarely think about what goes on behind the scenes.

To separate the forearm from the cadaver, Dr. Olson steadied the body while I sawed (with an actual hand saw) through the radius and ulna distal to the elbow. I used a scalpel to cut a vertical slit in the skin along the anterior side of the arm, from the wrist to the bottom. Then I cut a horizontal line along the wrist and pulled back two flaps of skin to expose the flexors. With a scalpel and forceps, I removed fascia and fat from each muscle and vessel to see the structures more clearly. I made a pencil sketch of the flexors and used the Thieme Atlas of Anatomy 2nd edition to try to identify the structures myself. Then I checked my answers with Dr. Olson. For the next few weeks, I repeated this process of dissecting more structures, sketching the muscles, and labeling the drawings with help from Dr. Olson and TA Sally Jo Detloff. I was generally able to dissect tissues without damaging them, although I accidentally cut the ulnar nerve and had to tie it together with string. Between dissections, I sprayed the arm with humectant and wrapped it in terry cloth to retain moisture.

CREATING THE ATLAS:

Elle_Baker_Foot_Bones
The first drawing was of foot bones.

When I had finished dissecting most of the arm and hand, I had a set of rough draft sketches to turn into final drafts. I redrew each drawing on larger paper and colored the new drawings with colored pencils. To make digital versions of the diagrams, I scanned the drawings and used the GNU Image Manipulation Program to fix margins and erase blemishes. Finally, I presented my work at NIU, at both the Phi Sigma Research Symposium and at the Undergraduate Research and Artistry Day poster shows. I enjoyed teaching the attendees everything I had learned about how the arm works. At URAD, my project won second place out of fourteen exhibits (NIU “URAD and CES Winners Announced.”)

THE DRAWING PROCESS:

Before starting the atlas project, I had never made scientific illustrations and had not taken any illustration courses at NIU. My artistic education was mainly from drawing for fun and taking public school art classes prior to college. Other than confirming the labels with Dr. Olson, I worked on the atlas diagrams independently.

I used photos taken in the lab as references for my color palette, which was meant to be realistic but still simple to understand. Hence, the atlas colors were bolder and more diverse than in the actual arm, where arteries and vessels were the same colors and everything turned more orange over time. The nails were colored to match the cadaver’s nails, which were, in fact, dark magenta. See the final Forearm Atlas diagrams: Flexor Compartment Layers 1-3, Flexors in the Palm, Extensor Compartment Layer 1, and Lateral View: Extensors.

Elle_Baker_Lateral_Extensors
One of the first atlas quality drawings.

 

Other students could benefit from drawing their own diagrams of their dissections. Doing so would help them memorize the names, locations and relationships between structures. While drawing, students might come up with deeper questions about how the body works, like I did during my project. Students could trade drawings and give each other feedback about the clarity of the diagrams. Students would be reminded to focus their critiques on legibility and accuracy rather than on aesthetic appeal. By making their diagrams understandable to others, students would improve at teaching and communicating. Ideally, they would also have fun improving their drawing skills.

Thank you to HAPS for the Student Grant, and thanks to NIU’s Office of Student Engagement for providing me a grant from the Student Engagement Fund. This project was supported by the Body Donation Program at Northern Illinois University, supervised by Dr. Daniel Olson, Director of the Anatomy Laboratory, which ensured the proper and respectful handling and disposal of the tissues used in this project.

Literature Cited

NIU. “URAD and CES Winners Announced.” NIU Today, 26 Apr. 2017, Retrieved from http://www.niutoday.info/2017/04/26/urad-and-ces-winners-announced/.

Office of Student Engagement and Experiential Learning. “URAD Program 2017.” Northern Illinois University, 2017, Retrieved from http://niu.edu/engagedlearning/_pdfs/urad/urad-program-2017.pdf.

Schuenke, Michael, et al. Atlas of Anatomy. Second ed., New York, New York, Thieme Medical Publishers, Inc., 2012.


Eliya Baker graduated from Northern Illinois University with a B.S. in Premed Biology and minors in Psychology and Chemistry. She is not formally trained in art, but enjoys making art as a hobby.  Her teacher and lab instructor is Dr. Daniel R. Olson Ed.D., the Director of the Anatomy Laboratory at NIU. 

“The Wave” – Neuron Action Potential Propagation

Some of our most popular blog posts describe teaching tips developed by HAPS members. We choose a handful of these to publish on the blog, but there are hundreds of tips that have been collected over the years. These little snippets are being linked to the HAPS A&P learning outcomes and posted to the HAPS website, for members only. So join HAPS now, and get access to many more teaching tips like this one.

Enjoy this teaching tip from HAPS Past President, Terry Thompson.

Objectives:

  1. Engage students with a kinesthetic demonstration of the action potential “wave” with ions moving in or out of membrane channels
  2. Generate visual memory tools to help students’ learning and long-term understanding
  3. Motivate critical thinking by having students analyze and evaluate various components of the activity as a model of the physiological events

Materials:

  • Color-coded cards: multiple cards with Na+/K+ on opposite sides; one card with ACh/Ca2+ on opposite sides; one card with neuron cell body/synaptic end bulb on opposite sides. Can use cardstock or plastic protective sleeves. Use large font to fill single page.

 Procedure:

  1. Line students up facing class (or each other if using two lines). Explain that students will represent the axolemma: phosphate “head”, lipid “legs”, voltage-gated channels “arms”.
  2. Give each student a Na+/K+ card and review relative concentration of each ion extracellular and intracellular. Designate: above “heads” as extracellular and floor as intracellular; right hand as voltage-gated Na+ channel and left hand as voltage-gated K+ channel. Start with Na+ card held toward observers, above their heads, in right hand.
  3. Demonstrate the depolarization/repolarization cycle by bringing Na+ card down in front of body, flipping K+ side toward observers as pass to left hand, then move above head.  Have all the students practice this synchronously until they feel comfortable, saying “depolarize” and “repolarize” out loud to help.  Discuss the electrogenic activity of the Na+/K+-ATPase pump as it relates to this kinesthetic demonstration.
  4. Review continuous conduction and challenge them to now complete the same movements but this time in sequence, like the “wave” in a stadium.  Show the “neuron cell body” and “ACh” cards and discuss what initiates the impulse.  Can elaborate on difference between ligand-gated and voltage-gated channels; graded potential, threshold, and action potential; neurotransmitter for motor neuron or other neurons; dendrites, soma and axon hillock; etc.  Students will often come up with ideas of ways you could include other elements in the demonstration, or at least evaluate and understand what this particular activity as a model is NOT showing.
  5. “Start” the first person in line by saying “threshold”, and allow the “wave” to progress down the axon.  This usually elicits lots of laughing and suggestions from the audience.  Allow them to repeat until they produce a reasonable “wave”, starting each with a threshold stimulus.
  6. Finally as a reasonable “wave” is progressing down the line, run to the other end and flip your cards to show synaptic end bulb and hold the Ca2+ card above your head.  When the wave reaches you, bring the Ca2+ down and flip to ACh, passing it above your head for release of neurotransmitter at synapse with muscle or another neuron.  Discuss this added activity to the model as a way to summarize the activity.
  7. Extensions can include discussing what parts of this demonstration could be improved on or don’t accurately reflect the physiology.  Can also discuss what would need to be changed to demonstrate saltatory conduction instead of continuous conduction.

NOTE: This activity was also presented by Terry Thompson at 2016 HAPS Atlanta Conference as part of the group workshop entitled “Add Drama to Your Classroom – Great Kinesthetic Activities for Students.”

Teaching Histology Without a Microscope

This quarter I am teaching a histology unit without a microscopy lab. Wait, histology without microscopes… what!?!? I have never experienced a histology course without a lab component and when I first heard this I was very surprised. How do you teach histology without microscopes? What about the concept of magnification? Isn’t operating a microscope a necessary skill? Then I read a couple of journal articles and considered the merits of a purely virtual histology course.

Everyone loves histology! (Image accessed on 3/18/18 from https://commons.wikimedia.org/wiki/File:Oligoastrocytoma_histology_HE.jpg)
Everyone loves histology! (Image accessed from wikimedia on 3/18/18)

Unless they are involved in a research project requiring optical microscopy or a pathologist analyzing samples, how frequently does the average researcher or medical professional actually use a light microscope? Could time spent practicing optical microscopy be better used learning other skills more relevant to their studies? Maybe career specific workshops or SPSS training? Microscopes are expensive and require upkeep. Could funds instead be used for resources needed in other courses. *cough cough Gross Anatomy cough*

Virtual microscopy is much more efficient for an institution and the students. A college or university could collect a large bank of images that can be updated continuously and won’t deteriorate over time. Online and long distance students are able to fully participate in labs. Slides can be shared rapidly between institutions without risking damaged or lost mail. Instructors can draw on slides to highlight structures without damaging them and students can compare slides of different magnifications or staining techniques side by side.

Histology curriculum often focuses on identifying structures in tissues and relating cell biology to the function of organ systems more than manual lab work. Students could practice reading slides as part of an active learning activity instead. Could microscopy be a workshop or research elective? Training would still be available for students, but only if they are planning to use this skill. This way students genuinely interested in microscopy could receive more individual attention from faculty.

So really, if you consider it, are students losing that much in a histology unit without a microscope? The course I am teaching is “Cell and Tissue Structure and Function.” It is part of the Biochemistry department. Students learn biochemistry and cell biology for the first seven weeks and end with a histology unit from me. We covered the four basic tissue types, integument, circulatory system, cartilage, and bone. The course is part of a physical therapy program. A laboratory component may be important in a course designed for future histologists, but these are physical therapy students. My lectures are packed with images, I have a workshop day set aside to practice analyzing slides, and I think they’ll be okay. 

These are some of the papers I read while thinking about this change:

Mione, S., Valcke, M., & Cornelissen, M. (2013). Evaluation of virtual microscopy in medical histology teaching. Anatomical Sciences Education, 6(5), 307-315.

Mione, S., Valcke, M., & Cornelissen, M. (2016). Remote histology learning from static versus dynamic microscopic images. Anatomical Sciences Education, 9(3), 222-230.

Thompson, A. R., & Lowrie, D. J.,Jr. (2017). An evaluation of outcomes following the replacement of traditional histology laboratories with self-study modules. Anatomical Sciences Education, 10(3), 276-285.


Post comes from Julie Doll, MS, Anatomy Instructor in the Department of Anatomy for Chicago College of Osteopathic Medicine at Midwestern University. 

Quick analogy for subclavian artery name changes

Although it is not a particularly difficult concept, sometimes students have trouble remembering the different names that the subclavian artery takes on as it passes through the superior mediastinum and base of the neck into the axilla (as the axillary artery) and arm (as the brachial artery), or they don’t quite get that it is the same vessel with three different names.

Every one of my students has to drive along these roads to get to school.
Every one of my students has to drive along these roads to get to school.

One thing I do in lecture and lab is to analogize this name change using name changes for streets in town. Fortunately, I work at a university (Benedictine University in Lisle, IL) that is situated on a road (College Road) that changes name to the north (Yackley Avenue) and to the south (Wehrli Road) without changing direction appreciably. Every student has to drive along these roads to get to school. I tell my students that the subclavian artery is like Yackley Avenue, and when it crosses the lateral edge of the first rib (in this analogy, Maple Avenue, see Figure), it changes name to the axillary artery (College Avenue); it changes name again after crossing the inferior margin of the teres major muscle (Hobson Road, see Figure), at which point it becomes the brachial artery (Wehrli Road). I would wager that many (most?) towns in the United States have roads that change names in the same way, so that the analogy could be adapted to local conditions. A particularly good example, in Washington, DC, is Constitution Avenue, which starts as I-66E, changes to US-50E/Constitution Avenue after crossing Roosevelt Bridge, and then turns into Maryland Avenue after crossing 2nd Street NE.

Of course, every semester the students and I question the sanity of anatomists and city planners alike for changing a perfectly good name again and again. I wonder how many students, driving home from my anatomy class, are thinking about the different names for the main artery of the upper limb as they drive along Yackley Avenue/College Road/Wehrli Road?


Robert McCarthy is an assistant professor in the Department of Biological Sciences at Benedictine University in Lisle, IL, where he teaches human anatomy and evolution to undergraduate biology and health science students. Robert is a biological anthropologist who studies the evolution of speech and language, the primate skull, hominin evolution, and human anatomic variation.

RAAS – Glug Glug Glug…

When I teach endocrinology students our unit on the adrenal gland cortical hormones, I always post a PowerPoint slide which depicts a Wikipedia image of the renin-aldosterone-angiotensin-system (RAAS).

Renin-angiotensin-aldosterone_system
This image is licensed CC-BY-SA 3.0 by A. Rad. Accessed on 12/4/17.

Its author does an elegant job of elaborating angiotensin II’s targets and responses, which include increases in sympathetic nervous system activity, tubular Na+ reabsorption and K+ excretion and H2O retention, adrenal cortex release of aldosterone, arteriolar vasoconstriction with a concomitant increase in blood pressure, and posterior pituitary release of ADH (arginine vasopressin) leading to reabsorption of H2O by the collecting duct. Overall there is an increase in the perfusion of the juxtaglomerular apparatus (JGA), which offers the negative feedback signal to reduce renin output by the JGA.

I point out to students this elegant, multiple-organ defense of falling blood pressure: the kidney (for renin release), liver, lung, adrenal cortex, hypothalamus (for both CRH and ADH), and kidney (for elevated perfusion) is all automatic. But when I show diagrams from multiple sources, including texts, I offer this question, “What is missing from these images?” I do prompt them with a clue about loss of perspiration during  workouts, but the ‘lights don’t go on’ until I reveal a PowerPoint shape with this on it, “Glug, glug, glug” – then they smile …. because they realize that drinking fluids provides the fastest return from hypovolemia…

Be thorough. Connect the dots.


Post comes from Robert S. Rawding, Ph.D., Professor in the Department of Biology at Gannon University in Erie, PA.

“I Was Too Embarrassed”

Exploring the Reasons Students Don’t Engage with Instructors to Improve Performance

“I was too embarrassed. He would think I was stupid,” replied my private tutoring client. This was her only response to why she did not meet with her professor after failing every exam the first time she took A&P 2 at a nearby university. I told her that most professors I know don’t assume that you are unintelligent if you’re struggling to understand material. The startling part of this exchange was her response to my reassurance, which was to ask, “Really?” She was genuinely surprised to hear that he would not assume she was an incapable student.

I didn’t think too much about this again until I picked up another student who also failed A&P 2 at a nearby community college. The story was the same, with a few added details. Despite failing 4 exams, no attempt was made to meet with the professor to discuss strategies for improvement. I asked her why. “Probably because I was embarrassed I did so poorly. I didn’t want to face my professor. Also, I didn’t think it would be helpful to go back and look, because reading the correct answers doesn’t really help matters if you don’t understand the content to begin with, so why make myself look stupid?” Now my curiosity was peaked. Is this how most students who don’t want to review and discuss their performance feel? Do they assume that they will either be judged, or that there’s nothing to be learned from seeing their mistakes? This might be especially true when exams are not cumulative. They may assume it’s better to just move on, in which case they are likely to repeat the same mistakes in preparing for the next assessment. It is easy to assume that only the students who are struggling will make appointments to review their performance, but from my experience, t’s usually the students hitting close to the average that view their exams, and the high and low scoring cohorts stay silent. The question then remains: Why would embarrassment stop a student from discussing their performance? Wouldn’t the desire to avoid more failure, or repeating a course, outweigh the risk?

Let’s assume for simplicity’s sake that you have created a supportive environment, you make yourself available, and when students do come, you provide constructive feedback that leaves them more confident and better prepared moving forward. However, the students who are struggling still don’t reach out. What else can, or should, an instructor do, for a student afraid of judgment? It is all too easy to write this off as a “silly” emotion, especially if you are a friendly, enthusiastic instructor (and I’ve never met a HAPSter who wasn’t!). However, after my experiences with the tutoring students over the summer, I decided to change up the language I used when I invited exams this academic year. I stressed the importance of failure in success.  I shared stories of my own academic struggles with students, stressing that some topics came naturally, and others were very hard to grasp, and took many hours of self-study outside the classroom to finally take hold. Finally, and what I feel made the biggest difference, I added the simple statement “please do not feel embarrassed to meet with me and review your exam” to my class email. The result? The number of my A&P students who came to review their midterms this year tripled from the five previous years.

For students, it does not always go without saying that we won’t judge their intelligence or ability. Say it. It takes almost no time, but you may see it make a big difference in the number of students who reach out for help. Do the easy things to get them in the door, and they may leave more self-directed, confident students. It may be hard for those of us who work in education to imagine letting embarrassment prevent us from getting better grades, but I’m sure that if we were all honest with ourselves, we could identify something we avoid because of fear of judgement. Students ultimately have to help themselves, but we can certainly help them get out of their own way.


Dr. Krista Rompolski is an Assistant Teaching Professor at Drexel University. 

Action Potentials can be a Puzzle

I found myself digging through a closet of scrap-booking goods last night in a frantic effort to find a 1 3/8” hole punch. I had been sparked by an idea that has been percolating for years, but I’ve never implemented. I wanted to build a cell with ions, channels, and charges so my students could manipulate the “players” involved in the resting membrane potential and an action potential.

This concept is particularly challenging for students. They could use chemistry, biology, and elements of physics to understand this system, but mine are woefully under prepared. Their eyes glaze over when they have to think about electrical gradients and chemical gradients working simultaneously. Add in channel types and applications to graphs that describe membrane changes in voltage, and even I’m starting to have an anxiety attack! When I teach this concept, the energy in my classroom is so thick, I could cut it with a knife. There has to be a better way.

berfore-ap
Before…

But so far, no amount of restructuring, dividing, or attempting to present just a “snapshot” in time had worked to facilitate the connection between what is occurring with ions and how it happens. So I cut out a giant cell, a little positive and negative sign, and all the different channels, and put them in a bag. That handy scrapbook punch allowed me to make sets of 10 potassium ions and 10 sodium ions in the colors I have been trying to get my students to associate with this concept. Voila- my students will now have an intracellular space on a table that represents the extracellular space…and all the important pieces as well.

before-ap
…and after.

Back in the classroom, as I drew on the board a picture of each step of the electrical changes experienced by the cell, they had to manipulate their cell. Did it work dreamily well? Probably not. Some students got it and visibly relaxed. But some students didn’t get it…and remained in a state of panic. However, I did discover that my students were pretty mixed up by the concepts of “depolarization” and “repolarization.” Because they can’t see the cell, sometimes this creates a mental block.

After class, a subset of students followed me to my office, where we played more with the model and I’ll be darned if they didn’t get to the point where they could set up their cell appropriately for each of the phases of the action potential! I could ask questions like, “Can the cell be stimulated again at this point?” And the question I love more, “WHY!?!” Light bulbs started turning on and several students took pictures so they could make their own model at home to use while studying.

This week in lab we use the HHsim program to study action potentials and this time, my new models will be on the table with them and they are going to have to show me what happens to explain the graphical results they get. My hope is that time, coupled with this paper model, will help them master the concepts.


Nichole Warwick teaches biology at Clatsop Community College and is a proud member of the HAPS Communications Committee.