Onlysisterade,
Welcome to HealingWell and please know we are glad you found our forum. I am sorry to hear you were in a car accident and now you have developed arthritis problems.
RE your question, unfortunately to the best of my knowledge, the doctors don't fully understand the reasons OA progresses or have therapies to effectively stop the progression. For OA in general, the most helpful advice is to maintain an ideal weight, avoid overusing joints that are damaged and follow a plan of exercise that strengthens the muscles supporting the joint. Your doctor or physical therapist should be able to help you with any of these.
Your best friend in your situation may be your Rheumatologist as he is the expert in guiding you into the future.
Kindly,
Kitt