title: Use of biochemical markers of osteoarthritis to investigate the potential disease-modifying effect of tibial plateau levelling osteotomy.
abstract: OBJECTIVE
  To evaluate the hypothesis that the concentration of the 1/20/5D4 epitope of keratan sulphate, cartilage oligomeric matrix protein and total sulphated glycosaminoglycans in synovial fluids from dogs with cranial cruciate ligament disease would be affected by tibial plateau levelling osteotomy. In addition, to evaluate the hypothesis that medial meniscal release or meniscal injury would alter the expression of these candidate biomarkers.
  
  
  METHODS
  Forty-one dogs with naturally occurring cranial cruciate ligament disease were recruited prospectively. Synovial fluids were collected from the index joint before surgery and six weeks and six months postsurgery. Following tibial plateau levelling osteotomy, synovial fluids were assayed for 1/20/5D4 epitope of keratan sulphate and cartilage oligomeric matrix protein concentration using an inhibition ELISA and for sulphated glycosaminoglycans using a direct dye-binding assay.
  
  
  RESULTS
  The sulphated glycosaminoglycans ratio did not change significantly during the study. Medial meniscal injury at entry was associated with lower concentrations of synovial fluid cartilage oligomeric matrix protein (P<0.05, unpaired t test). There was no association between medial meniscal release and the changes in marker concentrations, either from 0 to six weeks or 0 to six months.
  
  
  CONCLUSIONS
  Tibial plateau levelling osteotomy did not significantly alter the expression of the named candidate biomarkers. These findings reflect the limited nature of the arthrotomy or indicate that tibial plateau levelling osteotomy does not influence the progression of osteoarthritis (OA). From these studies, there is no evidence that tibial plateau levelling osteotomy affects cartilage metabolism.
authors.affiliation: Small Animal Division, Faculty of Veterinary Science, University of Liverpool, Liverpool L69 0BX, UK.
authors.forename: S L
authors.initials: SL
authors.lastname: Girling
authors.forename: S C
authors.initials: SC
authors.lastname: Bell
authors.forename: R G
authors.initials: RG
authors.lastname: Whitelock
authors.forename: R M
authors.initials: RM
authors.lastname: Rayward
authors.forename: D G
authors.initials: DG
authors.lastname: Thomson
authors.forename: S C
authors.initials: SC
authors.lastname: Carter
authors.forename: A
authors.initials: A
authors.lastname: Vaughan-Thomas
authors.forename: J F
authors.initials: JF
authors.lastname: Innes
mesh_terms: D000818:Animals; D016118:Anterior Cruciate Ligament / Q000601:surgery*; D000070598:Anterior Cruciate Ligament Injuries; D015415:Biomarkers; D004283:Dog Diseases / Q000378:metabolism*; D004285:Dogs; D004797:Enzyme-Linked Immunosorbent Assay / Q000379:methods / Q000662:veterinary; D000939:Epitopes / Q000032:analysis; D005260:Female; D006025:Glycosaminoglycans / Q000032:analysis* / Q000276:immunology / Q000378:metabolism; D007632:Keratan Sulfate / Q000032:analysis* / Q000276:immunology / Q000378:metabolism; D008297:Male; D010003:Osteoarthritis / Q000378:metabolism / Q000662:veterinary*; D010027:Osteotomy / Q000662:veterinary*; D011446:Prospective Studies; D012421:Rupture; D013582:Synovial Fluid / Q000737:chemistry / Q000276:immunology; D013977:Tibia / Q000601:surgery*
chemical_list: D015415:Biomarkers; D000939:Epitopes; D006025:Glycosaminoglycans; D007632:Keratan Sulfate