Some might say Derby the dog is disabled, but clearly they haven't seen him in action. 
 
 "He has always been the happiest dog I know," Derby's adopted human, Sherry Portanova, tells The Dodo. But before he met Sherry, things weren't so bright for him. 
 
 Derby was born with underdeveloped front limbs, and although he was otherwise a healthy dog, that one difference nearly caused him to be put down. The young dog's original owners decided they didn't want him anymore, and he soon wound up at the Peace and Paws Dog Rescue shelter in Hillsborough, N.H. But he wasn't unwanted for long. 
 
 Fortunately, Derby soon met someone who was not only compassionate enough to save his life, but also equipped with the know-how to improve it too. 
 
 That person was Tara Anderson, director at 3D Systems, a company that specializes in 3-D printing. When she heard about Derby's condition, she knew she had to do her part to give him a second chance — and perhaps find a solution to his mobility limitations. 
 
 After taking Derby in as a foster, Anderson set him up with a wheeled cart to make it easier for him to get around. And while it certainly did help, Anderson suspected that her team of designers could do one better. 
 
 The skilled staff at 3D Systems soon set about crafting a custom set of prosthetic legs that would not only help Derby to move more naturally, but that would also let him live out his full potential as an energetic pet. Several design attempts later, they finally settled on an oval-tread shape, designed to fit Derby's unique anatomy. 
 
 But even before getting that special gift made just for him, Derby found something even more important — a forever home with a new family who loves him, differences and all. 
 
 To Derby's adopted parents, the Portanovas, he was just an all-around happy dog, though he was soon about to get a whole lot happier. 
 
 The day came recently for Derby to try on the prosthetic limbs, and for the very first time in his life, experience the joy of running. 
 
 "It was incredible and emotional the first time we saw him run on his new legs," Sherry says. "Incredible because it was his very first time on them and emotional because he was so excited to be running." 
 
 Since then, Derby has barely slowed down, using his newfound freedom of movement to join his family on real runs around the block and to experience life a bit more like dogs who weren't born different like him. 
 
 "Derby was born with this deformity so he never really knew any different; he was a happy dog," says Sherry. "However, his new legs have allowed him to run on concrete, play with other dogs and overall be more mobile." 
 
 Check out footage of Derby in action below: ||||| Please enable Javascript to watch this video 
 
 LOVELAND, Colo. -- It’s still a dog’s life for a quadruple amputee out of Loveland. Brutus the Rottweiler is only the second dog ever known to have four prosthetic limbs. 
 
 He started walking with them in September 2014, when he was outfitted with the rear prosthetics. The front devices came 6 to 8 weeks later. 
 
 It hasn't always been an easy road. 
 
 Foster mom, Laura Aquilina, takes Brutus for a walk around the block, which ordinarily wouldn't sound like a challenge. 
 
 "He just has these little peg legs to get around on and he does a pretty good job inside the home," says Aquilina. But outside--he's adjusting to wearing prosthetics on each leg. 
 
 "You can't explain to an animal why you are putting these contraptions on their feet. You can't explain to them, that it's to help them," she says. 
 
 So Aquilina eases Brutus slowly into a life with artificial limbs. 
 
 The high-stepping hound sometimes resembles a bucking bronco. Exercises and play help the 2-year-old learn balance. 
 
 But Aquilina wants much more for him. 
 
 "He's able to walk in them. It's not always pretty. We want to be able to give him a higher function, where he can run and play with other dogs, go on hikes,” Aquilina said. 
 
 Brutus ended up disabled because he got frostbite on all four paws and his breeder amputated the damage himself, maiming him. And that's where OrthoPets of Denver came in. 
 
 "Brutus is an amazing case of a beautiful dog who was dealt a short hand," said Martin Kauffman, founder of OrthoPets. 
 
 His manufacturing company makes prosthetics for about 250 animals worldwide a year. 
 
 "He can get out and do normal doggy things. And it just makes you feel so good," he says. 
 
 It also makes Aquilina feel good that her furry friend is an inspiration for other animals with disabilities. 
 
 "If he ended up in a shelter they'd say he was unadoptable because he's missing his feet. I think it's good for people to know we can work with animals like this," she said. 
 
 Brutus' next step involves physical therapy at CSU's Veterinary Teaching Hospital in Fort Collins. 
 
 He'll also get an improved set of prosthetics. 
 
 All of it to help Brutus get around even better.
– Derby the dog is winning new converts to the concept of 3D printing. Derby is a husky mix who was born last year with deformed front paws, reports BuzzFeed. Lucky for him, an employee of a company called 3D Systems in Massachusetts took him in as a foster dog and eventually hit upon the idea of printing him new front legs. The result of Tara Anderson's idea has become a YouTube smash, notes the Dodo. Derby, incidentally, has been permanently adopted by a family.