By Ethan Snow
PhD
The human body is composed of a typical pattern of anatomy, yet every structure varies in form from person to person. For example, humans develop with a standard set of defined muscles, yet the shape and mass of each muscle varies significantly among individuals. Sometimes, “anatomical variations” develop – that is, anatomical structures that do not conform to the typical range of regular morphology (for example, an entirely separate “extra” muscle that develops in one person).
Human anatomy is so intricate that the prevalence of an anatomical variation is thought to be certain in every individual; in this regard, what makes each of us unique is the very thing we have in common. Certain variations can elicit complex symptoms, muddle diagnoses, and complicate treatments. Fortunately, though, most anatomical variations are asymptomatic and pose little to no clinical concern. Sometimes variations can even be beneficial; for example, an accessory muscle-tendon unit can be useful autograft material in musculoskeletal reconstruction surgeries.
Anatomical variations are challenging to study because they are often found incidentally. In surgery, clinicians operate in a limited window of visibility in order to complete procedures with minimal incisions. When surgeons find an unexpected variation in their operating window, they often only see part of it and are not able to expose the entire structure. Anatomists, however, dissect the entire body (as an embalmed cadaver) and expose variations in full detail. Cadaveric case analyses of anatomical variations provide clinicians with insights for adjusting protocols to suit variations during surgery and in noninvasive treatment plans, and they help anatomists teach clinically significant variations to students learning human anatomy.
Strategic anatomist-clinician collaborations foster the mutual exchange of expert-level skills to promote the highest-quality medical education and patient care, particularly involving anatomical variations. These collaborative relationships form the fundamental underpinning of evidenced-based medicine and embrace the “bench-to-bedside” model for making translational research influential to patient care.
Modern technology has improved the study of anatomical variations. Many anatomical case analyses now involve radiologic imaging, histopathology, digital modeling, and other contemporary techniques, making them more relevant to clinicians and patient care. In the fast-paced disciplines of education and medicine, innovations such as virtual reality (VR) are being used to advance anatomy education and improve patient care. While defined variations and clinical conditions can be simulated by technology and offer many impactful benefits, tech-based programs are currently unable to generate accurate models of potential anatomical variations.
For the nearly 2500 years, human cadavers from whole body donors have served instrumental roles in establishing anatomical knowledge, including what is known about anatomical variations. Human cadavers are unparalleled for tactile feedback, unscripted anatomical variations, and clinical associations. They also convey more than anatomy; they are considered by most students as their first patients and teach students about clinical anatomy, variation, disease, ethics, humanity, respect, and many other important values. Educators, clinicians, and students remain extremely grateful to whole body donors for their selfless contributions to advancing medical education, knowledge, practice, and patient care – particularly as related to anatomical variations.