It can't be cured at all.
Just like people if you keep moving it may ease the symptoms, stay sedentary will only exacerbate it.
If she hasn't had a comprehensive wellness exam in the last six months, get one.
The exam should include a complete blood workup, urine/fecal, dental, and if indicated UTD vaccines, x-rays and an echo cardiogram.
While there you may address your concerns regarding the arthritis, options, possible treatments, prognosis, and quality of life.
Then put your feelings aside and do what is best for the dog.
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