Pet Insurance & Preexisting Conditions

My dog broke her leg a couple of weeks ago and the most recent X-ray shows signs of arthritis as a result. She is still in the splint and we will be taking it easy for the foreseeable future, but am wondering if anyone has insight to how this may work with different insurance providers?

Also, if no treatment is needed for arthritis in the next 6-12 months are there providers where this would be covered?