Source:http://linkedlifedata.com/resource/umls/id/C0221684
AIR: WHAT: Morning stiffness or night pain of the back, improving with motion Pain and/or stiffness of the spine, prominent during the night or when waking up in the morning. The complaint typically decreases after some exercise or movement. WHY: It is a typical complaint of ankylosing spondylitis or other inflammatory diseases of the spine. HOW: Assessed by history. Ask if the patient ever wakes up at night with back pain or stiffness that subsides after some exercise. Report as present or absent.