title: Joint biomarkers in idiopathic femoral head osteonecrosis: comparison with hip osteoarthritis.
abstract: OBJECTIVE
  To compare concentrations of joint biomarkers in synovial fluid (SF) between idiopathic osteonecrosis of the femoral head (ION) and osteoarthritis (OA) of the hip joint.
  
  
  METHODS
  Levels of the joint biomarkers cartilage oligomeric matrix protein (COMP), antigenic keratan sulfate (AgKS), and hyaluronan (HA) in SF samples from 21 cases of ION and their relationship to disease stage and history of steroid use were assessed and compared to the result of 29 cases of hip OA.
  
  
  RESULTS
  In both the ION and hip OA groups, levels of COMP and AgKS in SF showed a significant positive correlation. The ION group had significantly higher levels of AgKS in SF than the hip OA group. In the ION group, stage II patients had significantly higher SF levels of both COMP and AgKS than those in stage III patients. No difference in level of HA in hip joint SF was found between steroid and non-steroid treated ION patients or between the stage II and III subgroups.
  
  
  CONCLUSIONS
  SF levels of COMP and AgKS may serve as useful joint biomarkers that reflect cartilage metabolism not only in hip OA but also in ION.
authors.affiliation: Department of Orthopaedic Surgery, Fujita Health University, Second Hospital, Nagoya, Japan.
authors.forename: Shinichi
authors.initials: S
authors.lastname: Kato
authors.forename: Harumoto
authors.initials: H
authors.lastname: Yamada
authors.forename: Nobuki
authors.initials: N
authors.lastname: Terada
authors.forename: Koichi
authors.initials: K
authors.lastname: Masuda
authors.forename: Mary Ellen
authors.initials: ME
authors.lastname: Lenz
authors.forename: Mitsuhiro
authors.initials: M
authors.lastname: Morita
authors.forename: Yasuo
authors.initials: Y
authors.lastname: Yoshihara
authors.forename: Osamu
authors.initials: O
authors.lastname: Henmi
mesh_terms: D015415:Biomarkers; D002356:Cartilage / Q000378:metabolism / Q000473:pathology; D064236:Cartilage Oligomeric Matrix Protein; D004797:Enzyme-Linked Immunosorbent Assay; D016326:Extracellular Matrix Proteins / Q000378:metabolism; D005271:Femur Head Necrosis / Q000378:metabolism* / Q000473:pathology*; D006023:Glycoproteins / Q000378:metabolism; D006801:Humans; D006820:Hyaluronic Acid / Q000378:metabolism; D007596:Joints / Q000378:metabolism / Q000473:pathology; D007632:Keratan Sulfate / Q000378:metabolism; D064235:Matrilin Proteins; D015207:Osteoarthritis, Hip / Q000378:metabolism* / Q000473:pathology*; D013582:Synovial Fluid / Q000378:metabolism
chemical_list: D015415:Biomarkers; D064236:Cartilage Oligomeric Matrix Protein; D016326:Extracellular Matrix Proteins; D006023:Glycoproteins; D064235:Matrilin Proteins; C577553:TSP5 protein, human; D006820:Hyaluronic Acid; D007632:Keratan Sulfate