Stem cell therapy, a relatively new treatment option for people and pets, has been shown to rejuvenate dogs with osteoarthritis-related ailments in clinical studies pending publication.

Although benefits cannot be seen on X-rays, at least 50 clients have paid approximately $2,500 for the therapy, which recently became available, after hearing that it improves a pet’s quality of life. Used to alleviate pain and potentially regenerate tissue, stem cell injections are getting positive reviews from veterinary specialists who participated in knee, elbow, and hip trials.

“As a pain management specialist, I am always looking for another viable tool for my toolbox,” said James Gaynor, DVM, MS, DACVA. “This has been great for us.” In his experience, the treatment has an 80+ percent chance for improvement in a pets condition.

Gaynor is one of about 80 veterinary specialists in North America who participated in trials and recently started offering the procedure to clients. A total of 150 client-owned dogs have received treatment through the studies and about 50 paid for the procedure, which uses stem cells extracted from a pet’s fat to replenish tissue damaged by osteoarthritis.

Veterinarians, who have given some patients more than one injection depending on their condition, are not sure how long the treatment lasts, but Gaynor said that when he asked clients if it was worth the money, "Everybody has seen enough improvement that they are pleased." He added that in horses, treatment benefits have been shown to last 18 months.

This fall the therapy will become available to primary care practitioners, who can receive certification online. More than 80 veterinary specialists who have already received certification.

Stem cell therapy has been used on about 2,800 horses since 2003, and it has received much attention. In 2007, more than 75 papers appeared in the literature about the use of this adipose-derived stem cells as well as at least 3,100 papers on adult stem cell therapy in recent years, said Linda Black, DVM, PhD, director of clinical development for VetStem Inc., a California-based company that owns the veterinary license on the technology. Veterinarians pay $950 plus shipping for the service, which isolates stem cells from a patient’s fat.

Small animal veterinarians are using it to treat osteoarthritis and other orthopedic conditions in dogs of all ages.

Although stem cell injections do not produce visible changes in arthritic tissue they have significantly improved the lameness of dogs previously incapacitated by joint pain, said Julie Ryan Johnson, DVM, vice president of sales and marketing for VetStem.

“It’s a quality of life thing,” Ryan Johnson explained. “Dogs feel better.”

Not only do dogs feel better, they show improvements in activity levels and the procedure seems to reduce pain, say veterinary specialists who say X-rays tell only part of a story.

“There’s more to a therapy’s efficacy than what shows up on an X-ray,” Gaynor said. “X-rays do not necessary correlate with pain and cartilage changes do not show up on X-rays.” Perhaps more importantly, he added, “Clients tell whether [a therapy] is working by what their pets do. I’ve never seen X-ray changes but I have seen active changes in dogs after their therapy.”

Cheryl Adams, DVM, CVA, has been involved in trials since 2005, and seen impressive results from stem cell injections in dogs ranging in age from 3- to 14-years-old.

"The key to providing the best response to stem cell treatment is appropriate case selection," Adams said. Patients should have a complete examination and work up including blood work, general health profiles with thyroid levels, and X-rays. The possibility of back problems - or other chronic issues - should also be eliminated.

“Appropriate education is critical for the clients so their expectations are realistic and they do not expect a miracle, or believe stem cells with treat every disease,” Adams added.

Although it has been licensed and used to treat several ailments in horses, ranging from polyarthritis and desmitis to fractures, stem cell therapy can only be used by small animal veterinarians to treat osteoarthritis, tendon and ligaments, polyarthritis, and fractures, said Ryan Johnson. The company is researching treatment of chronic liver disease, she added.

This fall veterinarians in general practice can log onto the VetStem website and take a three- to four-hour certification course that covers diagnosis and treatment, which requires joint injections. There are no contraindications because injected material is derived from the same patient and the technique is sterile, Ryan Johnson said.

Once a diagnosis has been made, veterinarians extract tablespoons of fat from an anesthetized pet and send vials to Vet-Stem in validated tubes. The company isolates stem cells and sends the concentrate back to the clinic within 48 hours.

Autologous fat cells are then injected into joints, said Ryan Johnson. Both Gaynor and Adams have also given the stem cells to dogs intravenously though joint injections will produce more focused treatment, they said.

Data from horse and human studies show that adipose-derived stem cells have an anti-inflammatory and can help resident cells by secreting growth factors and cytokines into the environment, said Ryan Johnson. "They can differentiate into many different cell types so they may be helping tissue regenerate," she added.