title: Synovial Fluid Lubricant Properties are Transiently Deficient after Arthroscopic Articular Cartilage Defect Repair with Platelet-Enriched Fibrin Alone and with Mesenchymal Stem Cells.
abstract: BACKGROUND
  Following various types of naturally-occurring traumatic injury to an articular joint, the lubricating ability of synovial fluid is impaired, with a correlated alteration in the concentration and/or structure of lubricant molecules, hyaluronan and proteoglycan-4. However, the effect of arthroscopic cartilage repair surgery on synovial fluid lubricant function and composition is unknown.
  
  
  OBJECTIVE
  Arthroscopic treatment of full-thickness chondral defects in horses with (1) platelet-enriched fibrin or (2) platelet-enriched fibrin+mesenchymal stem cells leads to equine synovial fluid with impaired lubricant function and hyaluronan and proteoglycan-4 composition.
  
  
  METHODS
  Controlled Laboratory Study.
  
  
  METHODS
  Equine synovial fluid was aspirated from normal joints at a pre-injury state (0 days) and at 10 days and 3 months following fibrin or fibrin+mesenchymal stem cell repair of full thickness chondral defects. Equine synovial fluid samples were analyzed for friction-lowering boundary lubrication of normal articular cartilage (static and kinetic friction coefficients) and concentrations of hyaluronan and proteoglycan-4, as well as molecular weight distribution of hyaluronan. Experimental groups deficient in lubrication function were also tested for the ability of exogenous high-molecular weight hyaluronan to restore lubrication function.
  
  
  RESULTS
  Lubrication and biochemical data varied with time after surgery but generally not between repair groups. Relative to pre-injury, kinetic friction was higher (+94%) at 10 days but returned to baseline levels at 3 months while static friction was not altered. Correspondingly, hyaluronan concentration was transiently lower (-64%) and shifted towards lower molecular weight forms, while proteoglycan-4 concentration was increased (+210%) in 10-day samples relative to pre-injury levels. Regression analysis revealed that kinetic friction decreased with increasing total and high molecular weight hyaluronan. Addition of high molecular weight hyaluronan to bring 10-day hyaluronan levels to 2.0mg/ml restored kinetic friction to pre-injury levels.
  
  
  CONCLUSIONS
  Following arthroscopic surgery for cartilage defect repair, synovial fluid lubrication function is transiently impaired, in association with decreased hyaluronan concentration. This functional deficiency in synovial fluid lubrication can be counteractedin vitroby addition of high molecular weight hyaluronan.
  
  
  CONCLUSIONS
  Synovial fluid lubrication is deficient shortly following arthroscopic cartilage repair surgery, and supplementation with high molecular weight hyaluronan may be beneficial.
authors.affiliation: Murray J. Grissom, MS, Michele M. Temple-Wong, PhD, Matthew S. Adams, BS, Matthew Tom, Barbara L. Schumacher, BS, Robert L. Sah, MD, ScD: University of California, San Diego, La Jolla.
authors.forename: Murray J
authors.initials: MJ
authors.lastname: Grissom
authors.affiliation: Murray J. Grissom, MS, Michele M. Temple-Wong, PhD, Matthew S. Adams, BS, Matthew Tom, Barbara L. Schumacher, BS, Robert L. Sah, MD, ScD: University of California, San Diego, La Jolla.
authors.forename: Michele M
authors.initials: MM
authors.lastname: Temple-Wong
authors.affiliation: Murray J. Grissom, MS, Michele M. Temple-Wong, PhD, Matthew S. Adams, BS, Matthew Tom, Barbara L. Schumacher, BS, Robert L. Sah, MD, ScD: University of California, San Diego, La Jolla.
authors.forename: Matthew S
authors.initials: MS
authors.lastname: Adams
authors.affiliation: Murray J. Grissom, MS, Michele M. Temple-Wong, PhD, Matthew S. Adams, BS, Matthew Tom, Barbara L. Schumacher, BS, Robert L. Sah, MD, ScD: University of California, San Diego, La Jolla.
authors.forename: Matthew
authors.initials: M
authors.lastname: Tom
authors.affiliation: Murray J. Grissom, MS, Michele M. Temple-Wong, PhD, Matthew S. Adams, BS, Matthew Tom, Barbara L. Schumacher, BS, Robert L. Sah, MD, ScD: University of California, San Diego, La Jolla.
authors.forename: Barbara L
authors.initials: BL
authors.lastname: Schumacher
authors.affiliation: C. Wayne McIlwraith, DVM, PhD, Laurie R Goodrich, DVM, PhD: Colorado State University, Fort Collins, Colorado.
authors.forename: C Wayne
authors.initials: CW
authors.lastname: McIlwraith
authors.affiliation: C. Wayne McIlwraith, DVM, PhD, Laurie R Goodrich, DVM, PhD: Colorado State University, Fort Collins, Colorado.
authors.forename: Laurie R
authors.initials: LR
authors.lastname: Goodrich
authors.affiliation: Constance R. Chu, MD: Stanford University School of Medicine, Stanford, California.
authors.forename: Constance R
authors.initials: CR
authors.lastname: Chu
authors.affiliation: Murray J. Grissom, MS, Michele M. Temple-Wong, PhD, Matthew S. Adams, BS, Matthew Tom, Barbara L. Schumacher, BS, Robert L. Sah, MD, ScD: University of California, San Diego, La Jolla.
authors.forename: Robert L
authors.initials: RL
authors.lastname: Sah