Asking what causes rheumatoid arthritis is really asking what you can act on. The answer is short, and much of it is about what is not yet known.
The cause of RA
OrthoInfo (AAOS) says the exact cause of rheumatoid arthritis is not known. Anyone who promises a single sure cause is claiming more than OrthoInfo does.
What the immune system is doing
NIAMS explains that RA occurs when the immune system, which normally helps protect the body from infection and disease, attacks its own tissues. That describes what happens, not why it starts.
Narrowing it down with a clinician
If your joint pain may be something other than RA, the NIAMS page on gout shows how another joint condition is described. The CDC arthritis overview and the WebMD pain management center give general background. In Little Falls, the useful step is a clinician who can examine your joints and tell the conditions apart. Ask what each possible diagnosis would commit you to over time.
Joint pain without a known cause
Why you have joint pain is a question for a clinician who examines your joints. Our comparisons stop short of medical advice, and a clinician decides what your symptoms mean.