title: The Use of Hyaluronic Acid and Corticosteroid Injections Among Medicare Patients With Knee Osteoarthritis.
abstract: BACKGROUND
  Hyaluronic acid (HA) and corticosteroid (CS) injections are frequently used in the management of osteoarthritis (OA) of the knee, despite a lack of strong evidence supporting their efficacy in the literature. The purpose of this study is to evaluate trends in HA and CS usage in Medicare patients over the past 15 years.
  
  
  METHODS
  The Medicare 5% national sample database was used to identify 581,022 patients (representing an estimated 11.6 million) with a diagnosis of knee OA between 1999 and 2013.
  
  
  RESULTS
  The percentage of newly diagnosed knee OA patients who received any injection trended from 39% in 1999 to 47% in 2006 and then declined to 37.5% in 2013. However, the mean number of injections per newly diagnosed OA patient nearly doubled from 0.27 to 0.45 for CS and from 0.18 to 0.36 for HA. Among those having both HA and CS injections, 69% had CS as first-line treatment, whereas 31% had HA first.
  
  
  CONCLUSIONS
  The percentage of newly diagnosed knee OA patients receiving injections peaked in 2007 and then decreased steadily through 2013, as did the proportion of patients receiving HA injections as first-line therapy. However, the number of injections per patient has increased significantly over the past 15 years in both groups.
authors.affiliation: Department of Orthopaedic Surgery, Dartmouth-Hitchcock Medical Center, Lebanon, New Hampshire.
authors.forename: Karl M
authors.initials: KM
authors.lastname: Koenig
authors.affiliation: Exponent, Inc, Philadelphia, Pennsylvania.
authors.forename: Kevin L
authors.initials: KL
authors.lastname: Ong
authors.affiliation: Exponent, Inc, Menlo Park, California.
authors.forename: Edmund C
authors.initials: EC
authors.lastname: Lau
authors.affiliation: Department of Orthopaedic Surgery, University of California, San Francisco, California.
authors.forename: Thomas P
authors.initials: TP
authors.lastname: Vail
authors.affiliation: Department of Orthopaedic Surgery, Mayo Clinic, Rochester, Minnesota.
authors.forename: Daniel J
authors.initials: DJ
authors.lastname: Berry
authors.affiliation: Department of Orthopaedic Surgery, Massachusetts General Hospital, Boston, Massachusetts.
authors.forename: Harry E
authors.initials: HE
authors.lastname: Rubash
authors.affiliation: Exponent, Inc, Philadelphia, Pennsylvania; Department of Orthopaedic Surgery, Mayo Clinic, Rochester, Minnesota.
authors.forename: Steven
authors.initials: S
authors.lastname: Kurtz
authors.affiliation: Department of Surgery and Perioperative Care, Dell Medical School at the University of Texas at Austin, Austin, Texas.
authors.forename: Kevin J
authors.initials: KJ
authors.lastname: Bozic
mesh_terms: D016208:Databases, Factual; D005260:Female; D005938:Glucocorticoids / Q000008:administration & dosage*; D006801:Humans; D006820:Hyaluronic Acid / Q000008:administration & dosage*; D007270:Injections, Intra-Articular; D007719:Knee Joint; D008297:Male; D006278:Medicare; D008875:Middle Aged; D020370:Osteoarthritis, Knee / Q000188:drug therapy*; D014481:United States; D055675:Viscosupplements / Q000008:administration & dosage*
chemical_list: D005938:Glucocorticoids; D055675:Viscosupplements; D006820:Hyaluronic Acid
keywords: corticosteroid injections; hyaluronic acid; intra-articular injections; knee osteoarthritis; osteoarthritis