The acromion process, a bony projection on the scapula that goes over the top of the shoulder, typically has three variations on the bottom – flat, curved or hooked. Because muscle runs underneath the acromion, a smooth surface is much more conducive to movement. When the bone is hooked or curved, it may interfere with the sliding of the tendon and increase the risk of a rotator cuff tear. 

Showing a two-dimensional cross section of this area may give students an understanding of the configuration of the different parts. But a three-dimensional physical model allows students to look at it from different angles and see how a hook shape or projection digs into the muscle and tendon. 

College of Health Sciences Department of Physical Therapy Assistant Professor Steven Snyder, PT, DPT, CSCS, worked with Educational 3D Visualization Specialist Gary Wisser to print 3D models of these three variations of scapula. 

“Rather than look at a textbook, you pick it up, hold it in your hand and see the variations,” Snyder said. “I use that in class demonstrations to follow up with concepts they have read about in textbooks. Students get a much better idea how these variations or malformations affect function, much more than drawing on a white board or with any 2D representation.” 

Using a 3D pen, Snyder has his students draw ligaments on a foot and ankle model and on a knee model. 

“The students thought it was fun. It improved their learning. They were really engaged with it,” Snyder said. “They had fun creating the models. I used the models they created as references for the lecture. Rather than handing out prefabricated models, they created them, so they were much more invested in it.”

Class of 2020 Doctor of Physical Therapy students review knee models they created with 3D pens using computer reference material. (Sunami Chun, WesternU)

Snyder credits Wisser and Manager of Educational 3D Technology Sunami Chun for bringing his ideas to life. He uses the models for his Anatomy 1 and Anatomy 2 classes for first-year Doctor of Physical Therapy students. 

“Gary and Sunami and their team make the magic work,” Snyder said. “I ask them, can we do this? A big part of our success is they sit down and work out the problem. How can we make this work? How can we get exactly what we want? The technology is there. We can create any physical thing you want. Why settle for just 2D textbook representation or a commercial model that isn’t exactly what you want?” 

Doctor of Physical Therapy student Chung Oh uses a 3D pen to recreate the PCL (posterior cruciate ligament) on a 3D printed knee model for the PT 5035 Anatomy II class. (Sunami Chun, WesternU)

Physical models enhance student learning more than 2D images, Snyder said, and research backs this. He did a pre-test and post-test with two different groups – one had a 3D printed femur and the other did not. The group with the 3D femur did much better on the post-test.  

Students need to study for their patients, not just for a test, Snyder said. Often the challenge of teaching difficult concepts is how to take something students read in a textbook and translate it to an actual patient in front of them. 

“Patients are three-dimensional,” he said. “Even with tablets, you are looking at a 2D screen. How do curves and spaces affect how you treat a patient? How do structures truly present rather than how they look on the page? 

“If there’s a physical object you think would help your teaching and help your students understand something, you can create it,” Snyder said. “It’s a great technology. It really opens up what you can do.”