The pain of arthritis may come from different areas. There are most likely several as proved by many research scientist. Sometimes muscle pain and fatigue will cause arthritic pain. A combination of these factors have been demonstrated in laboratory studies to cause the intensity of arthritic pain. The type of pain varies greatly from person to person.
Factors depend on amount of joint damage, the amount of heat or redness associated from the joint.
Doctors still understand only a portion of why arthritis causes pain and how to control it or prevent some of the more dangerous life-threatening types. Activities have clearly been demonstrated to affect pain. This also depends on which joint is being described, shoulder, foot, hand, etc. Each person has a different threshold for pain, which makes studying arthritis a bit subjective. Quantifying a subjective type of pain as a researcher is difficult.