title: Lavage solution temperature influences depth of chondrocyte death and surface contouring during thermal chondroplasty with temperature-controlled monopolar radiofrequency energy.
abstract: BACKGROUND
  Although radiofrequency energy can smooth and contour cartilage surface, it has deleterious effects on chondrocyte viability.
  
  
  OBJECTIVE
  Monopolar thermal chondroplasty in a 37 degrees C lavage solution, as compared with a 22 degrees lavage solution, will reduce chondrocyte death and result in greater smoothing of the articular cartilage surface.
  
  
  METHODS
  Controlled laboratory study.
  
  
  METHODS
  Sixteen chondromalacic samples from patients undergoing total knee arthroplasty were divided into two groups: 22 degrees C and 37 degrees C lavage solution. Each sample was divided into two equal parts and half of each group was treated for 10 seconds and the other half for 15 seconds.
  
  
  RESULTS
  Confocal laser microscopy demonstrated that the depth of chondrocyte death in the 37 degrees C lavage solution group was significantly less (range, 200 to 340 microm) than that in the 22 degrees C solution group for both 10- and 15-second treatment times. Scanning electron microscopy demonstrated that the cartilage surface in the 37 degrees C lavage solution group was smoother than that in the 22 degrees C solution group for the 10-second treatment time. Energy delivery power in the 37 degrees C lavage solution group was significantly lower than in the 22 degrees C solution group for both treatment times.
  
  
  CONCLUSIONS
  Thermal chondroplasty with 37 degrees C lavage solution resulted in less depth of chondrocyte death and produced smoother surfaces than with 22 degrees C solution for 10 seconds of treatment.
  
  
  CONCLUSIONS
  Less chondrocyte death would permit increased use of thermal chondroplasty.
authors.affiliation: Comparative Orthopaedic Research Laboratory, Department of Medical Sciences, School of Veterinary Medicine, University of Wisconsin-Madison, Madison, Wisconsin 53706-1102, USA.
authors.forename: Yan
authors.initials: Y
authors.lastname: Lu
authors.forename: Ryland B
authors.initials: RB
authors.lastname: Edwards
authors.forename: Shane
authors.initials: S
authors.lastname: Nho
authors.forename: Brian J
authors.initials: BJ
authors.lastname: Cole
authors.forename: Mark D
authors.initials: MD
authors.lastname: Markel
mesh_terms: D000368:Aged; D001178:Arthroplasty / Q000379:methods / Q000592:standards; D002358:Cartilage, Articular / Q000601:surgery*; D017115:Catheter Ablation / Q000009:adverse effects*; D016923:Cell Death; D019902:Chondrocytes / Q000502:physiology*; D005260:Female; D006358:Hot Temperature / Q000009:adverse effects; D006801:Humans; D007719:Knee Joint / Q000601:surgery; D008297:Male; D007507:Therapeutic Irrigation