The dog in a video from North Carolina State's vet school has something new.
"The bone goes on the inside and then the skin gets wrapped around the outside," said North Carolina State engineering professor Ola Harrysson.
It's a titanium implant that connects the artificial leg directly to the dog's bone.
Professors are showed it off at the Regenerative Medicine Foundation's conference in Berkeley. You see, they didn't go out and buy that. They made it on a 3D printer.
"We actually purchased one of the first metal 3D printers in the world that is called an electron beam melting machine," Harrysson said.
At the university's engineering department, they're using that machine to print out bones and joints for our furry friends.
"It needed a total knee replacement, and total knee replacement doesn't exist for cats," Harrysson said. "So we designed this unique implant."
Each implant is one of a kind, made for the patient. And 3D printing lets them make it out of light, flexible mesh.
"The bone will grow into these meshes and fill it in completely," Harrysson said. "And now you have a repair, and this will become one with the bone."
More than just a melding of metal with bone, this is a melding of disciplines. Remember, these are engineers attending a conference full of doctors; something that could soon become a lot more common.
"As engineers we're trained as problem solvers," said Paul Cohen, Industrial & Systems Engineering department head. "So are doctors. But we're trained in very very different ways."
Now they're tackling a new problem -- re-growing soft tissue.
"Cells will attach to these scaffolds and start growing," explains NC State Engineering Professor Rohan Shirwaiker.
Yes, that's a human ear. Or, it will be.
It's printed out of a rubbery material that stem cells love to grow on, with a special 3D printer called a bioplotter. As the new tissue forms, that scaffold just melts away.
"What you end up with after a few months to years is this organ, which is made up of your own cells, which is live and functioning," said Shirwaiker.
It could work for internal organs.
It's already being tested for use in animals.