With inactivity, the joint stiffens and can give the sensation of locking up when trying to move it again. Stiffness is defined as a temporary sensation that the joint and periarticular musculature are tight and difficult to move.
Stiffness, particularly early-morning stiffness, is a symptom eagerly sought y rheumatologists, since it is believed to be a cardinal symptom of inflammation.
Morning stiffness, after a full night of inactivity, usually lasts about 15-30 minutes. This is contrast to rheumatoid arthritis where morning stiffness can last for hours. Other inflammatory conditions, such as systemic lupus erythematosus, ankylosing spondylitis and polymyalgia rheumatic, are also accompanied by morning stiffness.
Perhaps the most plausible explanation is an accumulation of fluid in and around joints during sleep.
What is morning stiffness?
