Lavage solution temperature influences depth of chondrocyte death and surface contouring during thermal chondroplasty with temperature-control led 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 37degreesC lavage solution, as compared with a 22degrees 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: 22degreesC and 37degreesC 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 37degreesC lavage solution group was significantly less (range, 200 to 340 mum) than that in the 22degreesC solution group for both 10- and 15-second treatment times. Scanning electron microscopy demonstrated that the cartilage surface in the 37degreesC lavage solution group was smoother than that in the 22degreesC solution group for the 10-second treatment time. Energy delivery power in the 37degreesC lavage solution group was significantly lower than in the 22degreesC solution group for both treatment times. Conclusions: Thermal chondroplasty with 37degreesC lavage solution resulted in less depth of chondrocyte death and produced smoother surfaces than with 22degreesC solution for 10 seconds of treatment. Clinical Relevance: Less chondrocyte death would permit increased use of thermal chondroplasty. (C) 2002 American Orthopaedic Society for Sports Medicine.