I started Atkins on 5/30/13. At that point I had chronic pain in my lower back and heel - enough that I couldn't walk through a store without a cart or even to the mailbox. I have one flight of stairs in the house (13 steps) and could not ascend except by getting down on all fours to climb. Two days (yes, that's two days) later, I ran up the stairs without even touching the railing. Incidentally - the day I began was my 58th birthday and I was seriously considering buying a Hoveround. Today - 8 days later I walked a half mile. Believe me when I say that going off Atkins means dying...I'm here for life.
Just getting off foods that cause inflammation can make a HUGE difference in arthritis. The worst of those are wheat and other grains. Many other health conditions can likewise benefit, but Atkins gives you a great way to clean up the eating AND lose weight, both which will help arthritis tremendously.
It has for me too. That and exercise helps a bunch too.