John Sector, the owner of Shelby St. Veterinarian Hospital in Florence, who performed the surgery on Cowboy and Mr. Jones, had high praise for the therapy.
"This is potentially a game changer. We're seeing incredible results in the joints. We also see some unexpected improvements in other things, like skin conditions," he said.
Stem cell therapy is not just for pets who curl up on couches or ride in the backseat either. Delk said horses, donkeys, zebras and lions are also regular stem cell patients. He and his team recently traveled to the Middle East to perform the therapy on some prized racing camels.
However, stem cell remedies, even for animals, are still considered experimental. Shila Nordone, the chief scientific officer at the AKC Canine Health Foundation, a nonprofit group that funds health research for dogs, said that its use for joint regenerative purposes is exciting, but that the lower regulatory bar in animal medicine is both good and bad.
"It's good because we can do things sooner for our patients without 10 years of expensive clinical trials, but bad because we are still in the process of establishing best practices to ensure the procedures are the safest and most effective possible," she said.
Studies funded by the Health Foundation and others have been promising. One study of more than 150 dogs found improvements in joint stiffness, mobility and other joint health indicators in nearly 95 percent of arthritic cases. In some patients, improvements were seen in as little as a week while others took up to 90 days and required multiple injections.
The cost of a single procedure is $1800-$3,000, depending on the area of the country, the species of animal and severity of joint damage. Even those with pet insurance can expect to pay out of pocket.
Owners like Perry believe it is worth every penny.
"They are completely different dogs. It absolutely changed their lives," he said of Cowboy and Mr. Jones. "It changed mine too -- I got my dogs back."