3D Prosthetic Paws Allow a Pup to Run, Stand Upright Derby, a husky pup, got a second set of prothetics to stand up straight.

 -- One lucky pup has gotten a second chance at standing tall, thanks to prosthetic paws, a new technology developed by 3D Systems, that allows the dog to run, stand and sit like any other.

Derby, a husky-mutt dog, was born without fully-formed front paws. Without his paws, the 2-year-old dog was forced to crawl and walk on his hind legs.

“He was scooting around on [his] nubs and chest,” Melissa Hannon, who rescued Derby through her organization, Peace and Paws, told ABC News in an interview last December when Derby got his first prosthetic paws.

Last year, Derby got a pair of custom prosthetic paws that were made by 3D Systems, a company that creates 3D designs and fabrications for clients. The first set of paws, allowed him to run on all fours, but he was hunched forward.

Now Derby has an upgrade with grown-up prosthetic paws. These new legs allow him to stand at his full height.

"Derby took to his new prosthetics very well," Sherry Portonva, Derby's owner, said in a video released by 3D Systems. "They raised him up to his proper height," he's sitting like how a real dog sits, which he's never been able to do."

The designers responsible, including the original designer of his early paws, Tara Anderson, had some trouble scaling the new legs, so that Derby could reach his full height and sit down with his two legs upright.

"Because our first circular 'blade' design was so successful, our initial thought was simply to scale the original," the company said in a statement. "What we had not accounted for in this second iteration, however, was that while we managed to elevate Derby to the appropriate height, the results of the scaled design were too ungainly for easy movement."

Instead the team used a new harder material and a "knee-like" structure to give Derby more stability. The figure eight light structure allows Derby to stand at his normal height for the first time and to finally sit like a normal dog with his legs in front.

“This past year has been amazing for us and for Derby,” Portonva said. “We can’t wait to see what the future holds.”