The primary school teacher found writing on the blackboard, stapling posters on walls and other everyday teaching tasks difficult. Some days she was unable to walk.
However, to look at her now, people wouldn't be able to tell she suffered from such a debilitating condition, she said.
This was due to her early diagnosis and treatment.
These days Ms Clark coaches children's netball, softball and flipperball and teaches part-time at Golden Sands School. She also opens her house to traumatised children through Homes of Hope and is in the process of becoming a foster parent through Child, Youth and Family.
But having been diagnosed at 22 with something typically linked with old age was a bitter pill to swallow.
"It is different from when you are old. You are cut down in the prime of your life. For me it was my 20s. You feel like you've lost a bit of your life, you've missed out on that."
Things typical 22-year-olds looked forward to such as a career, socialising and having children were now unlikely.
"It's hard to make people understand," she said.
"When I first got diagnosed I didn't know anyone. I felt really alone - 'What do I do? What are these medications?' I was totally blown away by it."
Ms Clark struggled to find other young arthritis sufferers that live in New Zealand.
"Back then there was absolutely nothing to cater for people my age. The only support groups were held in churches in the middle of the day. But I still wanted to work."
Since then, Ms Clark has formed the Facebook group Super Young Arthritics of New Zealand, so no one had to feel as isolated as she once did.
The page now has 280 'likes' from people who share concerns, questions and discussions about MSD conditions.
Arthritis Appeal Week runs this month from September 25 to October 1.
