One of the most challenging aspects of anatomy for new students is the specialized terminology. We use these terms so we can communicate effectively. But, achieving this goal requires a shared understanding of standard terms and their meanings.

Last fall, there was a robust discussion on HAPS-L about defining “hyperextension”. In general, the contributors agree that extension increases the angle between segments of a common joint. But, defining hyperextension was trickier.

Some sources define hyperextension by the angle of the joint. However, there is disagreement over whether the “neutral” (normal anatomic) position should be designated as 180° or 0°. Furthermore, in some joints, extension normally exceeds the neutral position. So, an arbitrary limit based on the angle between adjoining bones will be difficult to apply universally.

Another option is to use the basic definition of extension as movement relative to normal anatomic position without reference to specific angles. While this is more practical, it makes the definition of hyperextension more complex. For example, the metatarsophalangeal, talocrural, and acetabulofemoral joints all normally extend past NAP.

At a minimum, the definition is in the name:  ‘hyper’ means ‘beyond’ or ‘over’, so generally, it is extension beyond the normal range of motion. However, even that definition has its own difficulties. Consider for example the degree of back or hip extension in this contortionist…

…this range of motion is far beyond what any of us would consider normal (or even desirable), but it is quite within the “normal” range for individuals trained for this activity.

Less extreme examples of “enhanced” extension can occur in cases of general ligamentous laxity and or of variations in joint surfaces that result in being able to extend (and in some cases, flex or rotate) beyond the range we have defined as normal. Elite athletes and other performers may often produce movements that exceed the textbook descriptions of “normal” ranges of motion.

After teaching A&P within and among several programs and majors, I have found that different disciplines often “flavor” terminology to highlight the issues most relevant to their professional concerns. For example, students of athletic performance or rehabilitation are concerned with the potential or actual injuries that often occur with hyperextension. However, even though hyperextension can cause injuries, as the examples above indicate, injury is not always the result.

The one element that all definitions have in common is that hyperextension is extending beyond the normal ROM. So, if we agree that this concept is essential to the general definition, we have a minimal standard of reference in the commonality in how the concept is expressed. Borrowing a page from C.S. Lewis, let’s call this “mere hyperextension”.

For “mere hyperextension”, we take the literal meanings of the prefix and root: hyper means “above” or “beyond” and “extension” is the movement of the joint in a way that increases the angle between structures on opposite sides of the joint. Thus, hyperextension would be extension beyond the usual anatomic range of motion.

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Andrew Petto recently retired as Distinguished Lecturer Emeritus from the University of Wisconsin–Milwaukee where he taught anatomy and physiology beginning in 2004. He began teaching human anatomy and physiology (to mortuary students) in 1989, and has since taught A&P to massage therapists, dancers, physical therapists, nurses, and herds of undergraduates at UWM, His PhD is in Biological Anthropology (comparative functional morphology) with post-doctoral studies in primate behavioral biology at Harvard Medical School (NERPRC) and in primate ecology in the Department of Anthropology at UW-Madison, supplemented by graduate studies in curriculum and instruction at Drexel University. His latest book, Human Structure and Function—an interactive textbook for students outside the sciences—was published by Tophat in 2017. His next book, Humans, is a collaboration with Alice Beck Kehoe of an introductory textbook on our species

Back in October, I shared a personal anecdote in part 1 “The Rule of Threes: Self-care advice for the A&P instructor”. In the post, I mentioned a list I created over the summer while preparing for the fall semester. This list included three behaviors to stop and three behaviors to start, both for the sake of my students and myself. I have always found stopping behaviors to be more challenging than starting new ones, so I thought it was best to first clear the space in my head (and my calendar) for new behaviors! As I wound down from the fall semester and reflected on what went well and what might need to change, I thought it was a good time to finish what I started.

My Three Things to Start:
Start off on the right foot
Many of us have (or have at least heard of) “syllabus day”. Traditionally, this is the first day of class, where no material is presented, but all policies and course expectations are reviewed. This might include reading through the syllabus with the students, page by page or administering a syllabus quiz…..  the possibilities are endless! Over the years, I have relied on this day to reassure myself that my students were clear on their schedule and all course policies, but (as I referenced in part 1) there is no guarantee of that. Over the summer, I sat back and thought to myself, “How quickly would I zone out if someone was delivering a presentation on policies and procedures to me? Is there a much more important message to send on my first interaction with my students, which for most of them is their first meeting with a professor in college?” After my experience this semester in A&P 1, my overwhelming conclusion is YES.

This year, I created a presentation on the first day that was primarily focused on welcoming them to my classroom and to the study of the human body. I told them who I was, and why I love being a teacher. I shared my endless fascination and passion for A&P, and how much I hoped that they would leave my class feeling the same. I spent time being honest with them about how often students struggle in A&P, and why that is so that they knew from day one that this course would demand a lot of time and attention from them. I shared several best practices/strategies for success that both I, and former students, have used. I even created a Monday-Sunday A&P work schedule for them (which several of my students have followed) to help them feel less overwhelmed while simultaneously making them aware of the amount of work necessary to be successful. Throughout the presentation, I shared many personal stories of my struggles and triumphs as a student so that they knew I understood how they might be feeling. I even addressed academic integrity in a different way. Rather than running down the penalties for cheating, I talked about why it ultimately hurts them to cheat, even if they are never caught. I ended my presentation asking my students to repeat aloud the phrase “You are NEVER bothering me”, which I have reinforced in every one-on-one or small group meeting, and in nearly every class period. This was easily the simplest, but most effective thing I’ve ever done as an instructor.

Start pulling back the curtain
One of the most controversial discussions I see in higher education is about instructor vulnerability, meaning, how much we let our students “in”. This applies to letting them in on both who we are outside the classroom and on our reasoning behind course design. I think we can all agree on one point: no one likes criticism, and all of us struggle with how to handle it. This year, I started talking openly with all my students about the rationale for each assignment, or the form of an assessment. I am sure we have all had end of semester course evaluations in which students lamented that there were too many, or too few exams, or that there wasn’t enough time on an exam, or that an assessment counted for too much. It’s easy to assume that these comments are only coming from students not achieving the grades they want, but what student wants their time wasted? Are grades the only thing that matters? Of course not! We want our students to enjoy themselves in a course, and to trust that we are not wasting their time.

Think about your own life experiences – how much more motivated are you in any activity when you truly understand the value of the activity, no matter how challenging? Conversely, how quickly will you doubt, or give up on an activity if you can’t see the benefit? Share your rationale with your students for what you ask them to do. For example, I had one student this quarter ask me why there was a time limit on their weekly, open book quiz. She reported that this caused her some anxiety which she felt was negatively impacting her performance. This was a great opportunity to talk about the importance of building stress-tolerance, especially as a future nurse! Since the midterm and final exam, all exams in her future courses, and eventually, the NCLEX are timed we talked about viewing the quizzes as an opportunity to prepare for all these higher stake situations. After this talk, she felt differently about the time limit. Share your rationale with your students. If you can’t come up with a clear rationale behind an assessment or its design, it might be an opportunity to re-evaluate.

Start scheduling fun
This is the Human Anatomy and Physiology Society. Every day, there are incredible conversations about best practices in teaching A&P, new teaching tips, and inspiring stories. I could add another piece of advice for the classroom, but I would likely be repeating someone else’s words, or thoughts you’ve already had!  What is not talked about nearly enough is life outside of the classroom. I don’t know about you, but left to my own devices on a weekend, I will work. Plans with friends fell through? No problem! I can read those journal articles or work on next semester’s presentations! Ah, the endless pursuit of the dopamine hit that comes with checking a box off on the to-do list. The problem is that the to-do list is endless. Our careers are not like home improvement projects, where once the crown molding is up we can finally relax. The perpetual fear I spoke of in part 1 about not being “enough” also comes with anxiety that I will somehow not get everything done. This fall, I decided I needed to make a weekly appointment with myself, whether to watch movies all day, bake any of the recipes I collected, go roller skating, or decorate the house we built last year that I’ve barely done more than sleep in! The point was, to do nothing “productive”.

If this sounds plain crazy to you, congratulations, you have a healthy balance to your life! For a long time, anything that didn’t have a clear “result” left me feeling guilty that I wasted precious time. In only a few short months, I am happy to report just how wrong I was. When I started scheduling fun, and being just “me” for even one day a week, I had time to rest and reflect on everything I was doing, and what I actually wanted to be doing at work. Now, I cannot wait to get back to the classroom every Monday. Despite (on paper) being busier than I have ever been in my career, I somehow feel calmer than ever, and confident that it will all get done. I have no doubt that this is easier said than done, otherwise, I would have done it years ago! If you too are living in a perpetual cycle of work, or guilt about not being “productive” enough, consider the idea that investing in yourself is the most productive thing you can do for everyone around you.

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Krista Rompolski is an Assistant Professor in the Health Sciences Department at Drexel University, Philadelphia, PA. She is an active member of the Human Anatomy and Physiology Society and the American Academy of Anatomists. Her teaching interests include pathophysiology, gross anatomy, and anatomy and physiology.

Last month we explained some of the outlets available with HAPS for publication. This week we are bringing you a glimpse of a Teaching Tip. The analogy provided below is a portion of a Teaching Tip recently submitted by HAPS member Micah Meltzer and his student Megan Spears. To see the full tip, visit the HAPS website

The Curriculum and Instruction Committee welcomes tip submission in all content areas; however, they are currently especially interested in tips for the following areas, which could use more tips to support our HAPS outcome guidelines.

• Muscular system: skeletal muscle metabolism, characteristics of muscle tissue types, principles and types of whole muscle contraction (twitch, motor unit or contraction types)
• Nervous system: neurotransmitters and their role at the synapse, sensory and motor pathways in CNS, ANS functions, body system survey
• General A&P introduction: body cavities/regions, directional terms in A&P

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Undergraduate physiology students seem to relate well to A.A. Milne’s characters Tigger & Eeyore from the Winnie-the-Pooh stories. The different behaviors of the voltage-gated Na+ & K+ channels can be likened to the personalities of Tigger & Eeyore, respectively. Tigger has a bouncy, excitable personality which is similar to the behavior of the voltage-gated Na+ channels (VGNC) responsible for rapid depolarization. In contrast, Eeyore is a mopey, sluggish character who behaves more like the voltage-gated K+ channels (VGKC) responsible for repolarization & hyperpolarization. These character associations can help students remember the differences between the two different voltage-gated ion channels involved in the generation of the neuronal action potential, which is a fundamental concept of neurophysiology.

Tigger Channels

Tigger is known for being friendly, energetic, and more than a little rambunctious. Tigger can be seen in the Hundred Acre Wood bouncing around and engaging excitedly with the world. Tigger’s exuberant and enthusiastic qualities are analogous to the rapid-open/rapid-close properties of the VGNC (Voltage-Gated Na+ Channel).

Neuronal VGNCs each contain a voltage-dependent activation gate & a time-dependent inactivation gate. The activation gate is triggered to open once a certain membrane potential, the threshold voltage, is present across the local membrane. The activation gates open rapidly allowing a significant influx of Na+ ions, causing depolarization and the rapid upstroke of an action potential, much like Tigger is known to suddenly burst into short-lived activity.  After a brief period of time (1-2 ms following activation), the inactivation gate rapidly “plugs” up the ion pore from the inside of the cell. This event abruptly stops Na+ ion influx, ending depolarization and defining the peak of the upstroke. The inactivation gate can easily be remembered by likening it to Tigger’s tail getting in the way.

Eeyore Channels

And then there is the gloomy Eeyore. Oh bother. In this mnemonic, his tail can be thought of as the sole activation gate swinging open and closed in response to changes in voltage. Eeyore is often seen moping around or moseying behind his friends around the Hundred Acre Wood. Eeyore’s slow and deliberate manner is analogous to the slow-to-open/slow-to-close nature of the VGKC (Voltage-Gated K+ Channel).

The VGKCs contain a voltage-dependent activation gate but, unlike VGNCs, do not contain an inactivation gate. The kinetics of the VGKC activation gate are slower, responding less quickly to changes in membrane potential when compared to the VGNC’s activation gate. The repolarization phase begins at the same time as the peak of the depolarization upstroke.  It takes that long to get most of the VGKCs opened allowing for significant K+ efflux. Once the membrane potential returns toward threshold voltage, the VGKCs begin to close, also slowly. If K+ continues to exit the cell after threshold voltage has been reached there will be a hyperpolarization phase.

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Micah Meltzer M.D. is an Assistant Professor of Biology at Contra Costa Community College (CA). He teaches Human Anatomy & Physiology, through a clinical lens, to students who are interested in (mainly) pursuing careers in the healthcare field.

 

 

Megan Spears is an Anatomy Teaching Assistant and student at Contra Costa College. She is on track to apply to medical school next Spring.