title: A chronic problem.
authors.forename: Paul
authors.initials: P
authors.lastname: Barr
mesh_terms: D000375:Aging; D019645:Arthroplasty, Replacement, Knee / Q000706:statistics & numerical data; D002908:Chronic Disease / Q000453:epidemiology* / Q000628:therapy*; D006801:Humans; D006278:Medicare / Q000706:statistics & numerical data; D010346:Patient Care Management / Q000458:organization & administration; D014481:United States