Merenia, who is the founder of Kotuku Foundation Assistance Animals Aotearoa, wondered what she could do to help Rica's mobility.
After a bit of research into stem cell therapy she contacted Nick Cooper who is one of the directors at CareVets New Zealand.
The company agreed to provide Rica with the therapy which has been given at the CareVets Kapiti clinic in Paraparaumu Beach.
Rica has had four sessions, which started late last year, and finished on Friday.
The non-invasive therapy, which uses sheep placenta cells, has helped re-energise Rica.
"It gives the dog's system a reboot and enables it to better repair the damage the arthritis has caused."
Merenia said there had been an improvement in Rica's mobility.
"I wouldn't say it has been spectacular but I would definitely say there has been an improvement.
"And other people who know us have also noticed an improvement in Rica."
Merenia was delighted at CareVets' help and generosity.
"Without their help it would have been difficult if not impossible to access the treatment because it is very expensive.
"I'm absolutely indebted to them because my dog is my world."
CareVets chief executive Nick Cooper said the company was happy to assist especially because of the foundation's work.
"Giving back to those that help in our community means a lot to all of our team at CareVets.
"We are extremely happy with the results with Rica."