Benjamin Spalding heard Pete screaming in his backyard aviary, and got there just in time to see a fox rip Pete’s foot off. Pete was loaded into his carrying cage, and after Spalding’s wife made a few phone calls to find an emergency animal hospital with an experienced exotic animal vet, they were off to Ryan Veterinary Hospital, which is part of the University of Pennsylvania School of Veterinary Medicine (Penn Vet) community,
After Pete was medicated and sedated, the emergency team saw that his left leg had been severed midway below his knee, and that he also had a small chest wound. A supportive bandage kept his leg comfortable overnight, and even though Pete had lost a lot of blood, the team knew he would likely survive, as birds can reproduce red blood cells much more quickly than humans can. A bird would have to lose 60% of its total volume of blood before showing any significant changes in blood pressure.
The next day, Pete had a round of antibiotics, a blood test, and a CT scan, so that his doctor could “characterize what was going on underneath the skin.”
“With this imaging, we were able to see the full nature of Pete’s injury, which really helped with surgical planning. We got Pete into surgery within 48 hours,” said Dr. La’Toya Latney, the Service Head and Attending Clinician of Penn Vet’s Exotic Companion Animal Medicine service.
After the surgeons removed some of the damaged tissue that had been infected from the fox bite, they were relieved to see that Pete’s femur and hip bones were intact, so they were able to save the bit of leg below his knee. Dr. Latney said Pete was affectionate and seemed to be much more comfortable post-op, but his journey wasn’t over. Most birds are able to handle just one leg, but only if they weigh less than 100 grams; since Pete is larger-bodied, he was looking at painful, long-term arthritis.
In order to get Pete the support he would need, Dr. Latney contacted Dr. Jonathan Wood, Staff Veterinarian in Penn Vet’s Neurology and Neurosurgery department; Dr. Wood has previously used 3D printed models in surgical teaching and planning.
Dr. Wood said, “I wanted to see what we could do for Pete with 3D printing. We think about animals that will rehab well and animals that will rehab poorly, similar to people. If there was a parrot that wanted to use what we made for him, Pete seemed to be a good candidate.”
While they looked a lot like Pete’s actual foot, they proved too fragile and thin to offer any support. Dr. Wood asked fourth-year student Gregory Kaiman to help out, and Kaiman, who’s interested in the potential benefits that 3D printing technology can provide to veterinary medicine, got in touch with the university’s Biomedical Library 3D printing group. This led him to design a custom model, instead of trying to make one using Pete’s CT scan.
Kaiman explained, “Dr. Wood was kind enough to share some pictures of Pete’s stump with measurements, and I began experimenting. After much trial and error, I got a little faster and a little better.”
The two made some major changes to the prosthetic leg design, but the big game-changer came when Kaiman found out that the Biomedical Library’s 3D printers, which include a Formlabs Form 2, a MakerBot Replicator 2, and a Stratasys uPrint SE Plus, can 3D print using different materials, textures, and weights. The new 3D printed prosthetic leg prototypes, made from extruded polymer resin, looked more like a walking boot and less like a foot, which meant that while they were bulkier, they were more stable. Pete allowed Dr. Latney to attach the prosthetic to his leg, and he was even able to bear weight on it.
Dr. Wood said, “It was fantastic to see Pete using something that we had made. This experience changed our thinking about how to approach other amputees.”
Pete seems to be taking everything in stride and still enjoys a full range of activity, including climbing. But his team, and his owners, are excited to get both the 3D printed prosthetic and the attachment system just right, so Pete can have an even better quality of life. This just goes to show that you can’t keep a good bird down. Discuss in the 3D Printed Parrot Leg forum at 3DPB.com.
[Source/Images: Penn Vet]