ORTHOPEDICS

By Sarah Carey

3D printing technology enabled a newborn calf with a broken lower jaw to fully recover.

“We were at the farm soon after she was born, and the staff asked us to look at her because she was standing with her mouth hanging open,” said Fiona Maunsell, BVSc, PhD, a clinical assistant professor with the UF College of Veterinary Medicine’s food animal reproduction and medicine service. Veterinarians from the service regularly visit the farm, run by UF’s Institute of Food and Agricultural Sciences and located in Hague, Fla., to provide care for its dairy cows and calves.

Trying to first stand after birth she nose-dived forward, hitting the ground right on the end of her chin, Dr. Maunsell said. Although the farm staff initially thought the injury was minor, when the UF team examined the calf more closely, they found she had a broken lower jaw.

Thousands of calves take their first steps every day, and almost all of them fall multiple times, but this was a first for Dr. Maunsell.

“This is the first time I’ve ever had a calf do this,” she said. “She was very feisty, though, running around her pen. And if you helped hold her mouth closed, she was able to nurse fine from a bottle.”

Although veterinarians can often repair breaks in the lower jaw in the field when they are at the front of the jaw, adjacent to or between the front teeth, this calf’s break appeared to be on both sides at the back of the jaw.

“That’s not something we could repair with field anesthesia and surgery,” Dr. Maunsell said. The calf arrived at UF’s Large Animal Hospital as an emergency case on Jan. 7. When radiographs did not shed much light on her injury, the surgical team recommended a computed tomography (CT) scan, which showed the bilateral breaks.

“The options for treating a calf with this type of fracture are orthopedic surgery, which was not economically feasible, conservative management with stabilization of the jaw, or euthanasia,” Dr. Maunsell said. “Given that she has had such a great attitude, we thought we’d try conservative management.”

Planning Potato’s cast.

Image courtesy of Jesse Jones/University of Florida

Working with Hongjia He, a graduate student in the Surgical Translation and 3D Printing Research Laboratory run by Adam Biedrzycki, DVM, an assistant professor of large animal surgery, and large animal surgery resident Heather Roe, DVM, sat down and built a jaw “cast” the printed on the 3D printer for the calf, which the veterinary technicians had named “Potato.”

Dr. Roe knew Potato would grow rapidly, so she assumed that they could adjust the initial 3D model to make it larger as she grew out of each cast, which is what the team wound up doing.

“The 3D print is made of a hard plastic, so we cushioned the print with cotton,” she said, adding that the final product came about through trial and error.

“The goal was to have something that stabilized her jaw so that the bone ends could heal together, allowed the calf to drink milk and was also taken on and off to clean as needed,” Roe said. “She was very wiggly, so having a cast that was easily applicable was important.”

After a few days, the calf was sent home, and follow-up imaging at 1- and 2-month intervals revealed that Potato’s fractures were healing well.

A second CT at the 2-month recheck showed that the fracture lines were almost fully healed and her jaw was stable on palpation, so the cast was removed.

“Because her ordeal in early life meant a delay in moving from milk to solid food, she is about a month behind her herd mates in development, but we now fully expect her to go on to become a valued—and much loved—member of the adult herd,” Dr. Maunsell said. MeV

The article originally appeared on the University of Florida, College of Veterinary Medicine website: https:// www.vetmed.ufl.edu/2021/12/20/jaw-dropping-recovery-uf-veterinarians-save-injured-dairy-calf-usingcreative-3d-solution/. It was edited for style and used with permission.