Lavage solution temperature influences depth of chondrocyte death and surface contouring during thermal chondroplasty with temperature-controlled monopolar radiofrequency energy.

BACKGROUND: Although radiofrequency energy can smooth and contour cartilage surface, it has deleterious effects on chondrocyte viability. HYPOTHESIS: 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. STUDY
DESIGN: 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. CLINICAL RELEVANCE: Less chondrocyte death would permit increased use of thermal chondroplasty. Copyright 2002 American Orthopaedic Society for Sports Medicine