What are some signs of arthritis and is it preventable?

Pain in joints. Some types of arthritis might run in the family. However, that does not mean a person cannot do things to delay onset or decrease the effect. Start by getting a family history. Take that to a primary care provider for consultation and examination. Ask for a list of activities to avoid and for things to do for prevention. If needed, ask for a referral to a rheumatologist.
No, but... You can minimize your risk of developing osteoarthritis by maintaining a healthy weight; symptoms include joint pain, stiffness, intermittent swelling, and, in more advanced cases, deformity; keeping your thigh and core musculature strong may help minimize your symptoms if you are developing oa. Talk to your doctor about your specific risk factors. Good luck!