Dr. Noel Fitzpatrick is a workaholic. He sleeps in his office, works hours on end and his social life is pretty much non-existent.
Why does he do it? For animals like Mitzi, Oscar and Yogi.
Fitzpatrick, who runs Fitzpatrick Referrals in Surrey, England, is the world's first vet to use prosthetics that give animals a new -- pain-free -- lease on life.
The neuro-orthopedic surgeon has pioneered biotechnology in animals, giving dogs and cats artificial limbs thanks to a blend of science, technology and art.
"I believe I was sent here for a reason -- to make a difference," Fitzpatrick said after a full day spent working on more than a dozen different cases.
"I enjoy restoring function. I see biology as an art form," he continued. "It's like painting a picture. I just want to restore pain-free function. I like to see a happy dog or cat. The bond of love between animals and humans is amazing."
His clinic was the first surgical centre in the world (either veterinary or human) to offer Intraosseous Transcutaneous Amputation Prosthesis (ITAP) technology, developed by Stanmore Implants Worldwide Ltd., for weight-bearing limb salvage procedures in any species.
The technology is now used by surgeons for human amputees.
Fitzpatrick and his staff have treated animals with ITAP in circumstances where amputation or euthanasia were the only other alternatives.
In 2009, Oscar, a black cat from Jersey, became the world's first bionic cat after Fitzpatrick and his team gave the cat two bionic paws after his had been sliced off by a combine harvester.
Mitzi, a German shepherd, has also been lucky thanks to the work of Fitzpatrick.
The dog from Dorset, England lost one of her rear paws after being trampled on by a horse. Since her paw was too damaged to salvage the only other option was amputation of her whole leg. But instead of amputation, Mitzi's owners sought help from Fitzpatrick who gave the dog a new artificial paw.
"It was our first attempt to put a prosthetic into an ankle itself. It was a whole new set of challenges," he said.
Fitzpatrick used the ITAP technology which allows Mitzi to walk and run at full tilt without a gait or limp. His team created a 3D model of Mitzi to develop the correct prosthetic and titanium rod that would match the dog's body structure.
The entire process including rehabilitation ran between August and December 2010, with Mitzi being let off her leash and allowed to run freely for the first time on Jan. 13, 2011.
"To see her run off the leash was amazing. It was breathtaking," Fitzpatrick said.
He's currently working on a 215-pound bullmastiff named Yogi who needs a new leg after infected cartilage ate away part of it.
"Keeping Yogi alive is important. I like to alter people's perceptions of what is important. My ego is important but what we are saying about life is important. Yogi's mom was suicidal thinking Yogi might die," Fitzpatrick said.
Fitzpatrick has been doing this work for seven years, and estimates his clinic has helped hundreds of animals.
He said he always knew he wanted to be a vet. Fitzpatrick grew up on a farm in Ireland, saying he entered the profession "out of necessity rather than out of desire."
Science, said Fitzpatrick, needs to be more artistic in its thought process and less linear or one-dimensional.
"Vets have the power over life and death. But we can't underestimate the power of an animal's love in society," said Fitzpatrick, whose work was featured last spring on the BBC series Bionic Vet.
Fitzpatrick, who jointly cares for a border terrier named Kirra with one of his receptionists because of his demanding work schedule, is constantly looking for new ways to further his work in biotechnology.
He is forever travelling the world to give talks on his expertise, and is working with doctors in the U.S. and U.K. to develop similar methods in biotechnology for human prosthetics.
But for now, his focus is on keeping Yogi alive.