3-D printing technology for dogs

Though still in its early stages when it comes to veterinary medicine, 3-D printing is being used for prosthetics as well as disease research.

One of the most fascinating technological advances in recent years, 3-D printing has a wide range of applications, from medical to industrial to artistic. It’s also making waves in the veterinary world and is being used in several ways to help dogs and cats.

Take Derby, for example (“Yakkity Yak”, AW V17I2). A dog born with deformed front legs, he once used a cart to get around. But his foster “mom”, who works for a 3-D technology company, developed 3-D printed prosthetics customized to meet Derby’s needs. Since then, he has been able to move and run like any other dog.

In another very different example, Alexis Noel, a doctoral candidate in mechanical engineering, made an enlarged 3-D mimic of a cat’s tongue in order to more closely study the mechanics of the Velcro-like “spines” that characterize the feline tongue (“Cat chat”, FW V19I1).

3-D printing not yet common for prosthetics and orthotics

Veterinarian Dr. Samuel P. Franklin, assistant professor for Small Animal Orthopedics at the University of Georgia, says that prosthetics and orthotics are used with increasing frequency to treat dogs and cats that have suffered amputations, or musculoskeletal or neurologic disorders. So far, though, with a few exceptions, 3D printed prosthetics aren’t often used in pets. “3-D printing is done, although it is less common for prosthetic or orthotic cases,” says Dr. Franklin. The technology is not readily available in most clinics so relatively few dogs have been fitted with 3-D prosthetics.

Aside from Derby, another example of a dog given a 3-D printed leg is Romina, a whippet who lost her front leg in an accident. Her articulated leg was fitted by specialists at Mexico City’s Universidad del Valle de Mexico’s Veterinary Hospital in early 2016. And then there’s Tiny, a young golden retriever who was born with only half her right front leg; she received a 3-D prosthetic leg from the Xavier MakerBot Innovation Center at Xavier University.

The advantage of 3-D printing is that it provides greater flexibility in manufacturing unique prosthetics for unusual cases where traditional prosthetics are not a good option. For example, Derby’s prosthetics were customized to his morphology and featured organic shapes and smooth curves suited to his body.

3-D implants

Along with prosthetics and orthotics, 3-D printing technology also has applications when it comes to medical implants, although again, it’s not yet that common in veterinary medicine. One example reported on by National Geographic (news.nationalgeographic.com/2016/08/prosthetics-animals-rescued-3d-dogs-cats) involved a ten-year-old feline bone cancer survivor whose illness caused a seriously weakened and painful knee joint. A team of veterinarians at North Carolina State University fitted the cat with a knee implant that was custom created for the animal using 3-D printing.

Helping researchers understand more about disease

Dr. Karen Burg, a colleague of Dr. Franklin’s, says that 3-D printing was introduced to human medicine over 20 years ago for pre-operative planning. It allows surgeons to view a model of an injured hip joint, for example, so the doctor can make preliminary decisions prior to operating. Because it takes highly specialized equipment to generate models, however, 3-D printing is not in high use for this type of surgical application in humans or in pets.

Currently, 3D printing in the veterinary field is mostly used for research purposes. Dr. Burg, who is in the Department of Small Animal Medicine and Surgery at the University of Georgia, specializes in 3-D printing as part of her biomedical engineering research on veterinary disease. Dr. Karen Burg focuses part of her research on understanding how the technology can be applied to studying disease; in some cases, this could hopefully eliminate the need for amputations in the first place.

Currently, 3D printing in the veterinary field is mostly used for research purposes.

“In the field of veterinary medicine, we are using 3-D printing to co-print animal cells and plastics,” says Dr. Burg. “Think of plastics with hair gel-like consistencies and cells from a patient (a dog, for example) co-printed into 3-D blocks of tissue. The idea is to make replicas of tissue blocks, use them to test combinations of therapies, and pinpoint the most appropriate option for a patient. Or we can simply study cellular processes in diseased or normal conditions.

“We can use software as simple as Microsoft Word for printing,” she continues. “Picture your name printed in multiple colors in Word. Now, instead of colored ink cartridges for printing text, we put bone cells in the green print cartridge, plastic in the black print cartridge, fat cells in the red one, and a medication in the purple one. Your name would be printed in those biological components rather than in ink. We’ve customized the printer to build layer upon layer in this fashion.

“We can also take clinical digital information from an x-ray, and print this with different components using the levels of gray in the x-ray to determine which cartridge dispenses at any given time. We could also use the same approach to print biological tissue replacements for a patient using cells taken from a dog, thereby personalizing that replacement.”

“We could also use the same approach to print biological tissue replacements for a patient using cells taken from a dog, thereby personalizing that replacement.”

Dr. Burg said 3-D printing can be a relatively simple process, but it can become highly complex when you consider the manufacturing aspects. “We can create tissue in a research lab, but creating a manufacturing process for clinical relevance and use is quite the undertaking.” While Dr. Burg cautions that there’s a great need for more technological development and education when it comes to the application of 3-D printing in veterinary medicine, she agrees that it’s an exciting field to be in.