“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 Dr. Fiona Maunsell, clinical assistant professor with the UF College of Veterinary Medicine’s food animal reproduction and medicine service.
The day the calf was born, it was seen trying to first stand after birth but nose-dived, hitting the ground right on the end of her chin, Maunsell said. Although farm staff initially thought the injury was minor, when the UF team examined the calf more closely, they determined she had a broken lower jaw.
Although veterinarians are often able to 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,” Maunsell said. She then contacted two of UF’s large animal surgeons to see if she could send the calf for radiographs and an evaluation.
The large animal team agreed to see her, and 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 CT scan, which involves multiplanar imaging and very effectively showed the bilateral breaks.
“The options for treating a calf with this type of fracture are orthopaedic surgery, which was not economically feasible, conservative management with stabilization of the jaw, or euthanasia,” Maunsell said. “Given that she has had such a great attitude, we thought we’d try conservative management.”
Working with Hongjia He, a graduate student in the Surgical Translation and 3D Printing Research Laboratory run by Dr. Adam Biedrzycki, assistant professor of large animal surgery, large animal surgery resident Heather Roe, sat down and built a jaw “cast” for the calf veterinary technicians named “Potato.”
“We used medical tape to hold her mouth closed to stabilize her jaw, but still allow her to nurse,” said Taralyn McCarrel, an assistant professor of large animal surgery, who worked with Roe on the case. “The tape was challenging to reset with Potato’s feisty nature and started to irritate her skin, whereas the cast placed in a similar fashion was much easier to reset.”
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.”
Fractures healing well
After a few days, the calf was sent home, and follow-up imaging at one- and two-month intervals revealed that Potato’s fractures were healing well.
A second CT at the two-month recheck showed that the fracture lines were almost fully healed and her jaw was stable on palpation, so the cast was removed.
“Our most recent recheck revealed that Potato has been thriving in her farm environment, with normal jaw function that has allowed her to continue to grow well,” Maunsell said. “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.”
“This calf’s case was particularly rewarding, because for her, it meant life and death,” Roe said. “Farm animals do not often have the financial backing to go to surgery, being production animals, and don’t have the ability to receive intensive care on the farm,” Maunsell said.
Aside from financial considerations, surgery in Potato’s case would have come with a high risk of serious complications due to her bilateral fractures and important nerves located in the jaw region, and because the bone in that area is soft and thin and may not have held implants well, McCarrel said.
“Even without any financial limitations, surgery would not have necessarily guaranteed a positive outcome,” she said.
The calf’s treatment was affordable, straightforward, noninvasive, adjustable and practical, the surgeons said.
“Potato was a joy to work with, so having her in the hospital was a delight,” Roe said.