Fabrication and assessment of 3Dprinted anatomical models of the lower limb for anatomical teaching and femoral vessel access training in medicine

Abstract

For centuries, cadaveric dissection has been the touchstone of anatomy education. It offers a medical student intimate access to his or her first patient. In contrast to idealized artisan anatomical models, it presents the natural variation of anatomy in fine detail. However, a new teaching construct has appeared recently in which artificial cadavers are manufactured through three-dimensional (3D) printing of patient specific radiological data sets. In this article, a simple powder based printer is made more versatile to manufacture hard bones, silicone muscles and perfusable blood vessels. The approach involves blending modern approaches (3D printing) with more ancient ones (casting and lost-wax techniques). These anatomically accurate models can augment the approach to anatomy teaching from dissection to synthesis of 3D-printed parts held together with embedded rare earth magnets. Vascular simulation is possible through application of pumps and artificial blood. The resulting arteries and veins can be cannulated and imaged with Doppler ultrasound. In some respects, 3D-printed anatomy is superior to older teaching methods because the parts are cheap, scalable, they can cover the entire age span, they can be both dissected and reassembled and the data files can be printed anywhere in the world and mass produced. Anatomical diversity can be collated as a digital repository and reprinted rather than waiting for the rare variant to appear in the dissection room. It is predicted that 3D printing will revolutionize anatomy when poly-material printing is perfected in the early 21st century.

The role of 3D printing in anatomy education and surgical training: A narrative review

“…Upon conducting a formative test following a 1-hour practical session comparing a cadaveric model and the 3Dp lower-limb model, no statistically significant difference was found in the average score (45.5% vs 50%, p = 0.46) (O'Reilly et al, 2016). Similarly, no statistically significant difference in theory test scores were reported when comparing an anatomical atlas, painted cadaveric skull and digitally painted 3Dp model (p = 0.669) for the teaching of skull anatomy .…”

“…In the field of surgery, the potential for 3Dp models has been explored for advanced simulation training that could be patient-specific, incorporate pathology and can share compatibility with surgical implants (Kurenov et al, 2015;Maragiannis et al, 2015;Narayanan et al, 2015). Physical models for more advanced clinical skills such as femoral vessel access that is compatible with a pulse generator and can be detected using Doppler ultrasound (O'Reilly et al, 2016). Researchers have also developed the physical properties of 3Dp materials when creating a 3Dp eye model that can potentially be used for funduscopic training .…”

“…With sufficient funding, a medical school could produce learning models suitable for use in a range of fields which extend from and beyond anatomy. One of the benefits of 3Dp is the reintroduction of anatomical variation in the advent of declining cadaveric dissections (Fasel et al, 2016;Moore et al, 2017;Nieder et al 2004;O'Reilly et al, 2016). Currently utilised plastic anatomical models and atlases are idealised and do not include the anatomical variations found during cadaveric dissection.…”

“…Such models are complemented by contrast CT, which can present surrounding vasculature and 'negative' structures such as air sinuses. (Kong et al;Kurenov et al, 2015;Lim et al, 2016;Maragiannis et al, 2015;McMenamin, et al, 2014;O'Reilly et al, 2016). These sophisticated models can also be digitally painted to enhance student learning, providing a learning advantage over monochromatic models (Ejaz et al, 2014).…”

“…They include colour coding Kong et al;McMenamin et al, 2014;O'Reilly et al, 2016), aneurysms that can be 'opened' to reveal internal structure , multi-material printing to represent calcified aortic valves (Maragiannis et al, 2015) and the addition of partitions to illustrate hepatic segments (Kong et al, 2016). In a recent study, a 3D lower limb model consisting of the bones and calf muscles was printed (O'Reilly et al, 2016). The bones of the leg and foot were printed separately and had magnets incorporated post-printing, allowing them to be attached and detached.…”