Osteoarthritis can affect any joint, but most commonly affects the hands, knees, hips, or spine. Factors that increase the risk of osteoarthritis include aging, being overweight, joint injury, and stress on a joint. Joint stiffness is typically worse in the morning but improves as the day progresses. Osteoarthritis of the spine however can occur without causing pain. Why certain facet joints with OA are painful and others are not is not known. Usually, spine pain caused by facet joint OA is worse with standing, bending backward, or lying flat in bed. Pain may radiate across neck into the shoulders, or across the low back into the buttocks or upper thighs. OA pain does not typically radiate into the arms or legs.
Borenstein DG, Wiesel SW, Boden SD: Low Back and Neck Pain: Comprehensive Diagnosis and Management. 3rd Edition. Philadelphia: W. B. Saunders, 2004.