Which symptom is more indicative of an inflammatory cause of joint pain rather than a mechanical cause?

Morning stiffness lasting more than 1 hour is a classic symptom associated with inflammatory joint conditions, such as rheumatoid arthritis. This symptom reflects the body's response to inflammation and is often characterized by heightened stiffness immediately upon waking, which can improve with movement throughout the day. Inflammatory arthritis typically presents with prolonged morning stiffness, as opposed to mechanical causes of joint pain, which usually do not result in such prolonged stiffness.

Other options may reflect joint pain but are not specifically indicative of inflammation. For instance, consistent pain during activity can occur in both mechanical and inflammatory conditions, local joint swelling can arise from various causes including mechanical issues, and chronic joint pain without effusion might suggest a longstanding problem that does not necessarily involve inflammation. Thus, the presence of morning stiffness lasting more than 1 hour is a key differentiator pointing towards inflammation rather than a mechanical issue.