Bone Transplants—No Donors Necessary!
This student-created prototype of a turkey femur is made from clay and other materials!Copyright 2016 David Breitbach and Deanna Grandalen, North Dakota State University
Students investigate the bone structure of a turkey femur and then create their own prototype versions as if they are biomedical engineers designing bone transplants for a bird. The challenge is to mimic the size, shape, structure, mass and density of the real bone. Students begin by watching a TED Talk about printing a human kidney and reading a news article about 3D printing a replacement bone for an eagle. Then teams gather data—using calipers to get the exact turkey femur measurements—and determine the bone’s mass and density. They make to-scale sketches of the bone and then use modeling clay, plastic drinking straws and pipe cleaners to create 3D prototypes of the bone. Next, groups each cut and measure a turkey femur cross-section, which they draw in CAD software and then print on a 3D printer. Students reflect on the design/build process and the challenges encountered when making realistic bone replacements. A pre/post-quiz, worksheet and rubric are included. If no 3D printer, shorten the activity by just making the hand-generated replicate bones.
Biomedical and materials engineers are continually designing improved prosthetics for humans and other animals. One rapidly emerging field of study in biomedical engineering is bone tissue engineering. For example, veterinarians can use the technology to design replacements for a dog’s leg bone or a bird’s wing bone that are specific to that animal’s anatomy and physiology. Like engineers, students follow the steps of the engineering design process to design and create bone prototypes that could replace nonfunctioning body structures.
After this activity, students should be able to:
- Design and create a turkey femur prototype that is similar in structure, mass and density to real turkey femurs.
- Use CAD software to generate 3D images of a turkey femur cross section.