The Effects of Radiofrequency Energy on Human Articular Cartilage: The Effect of Power Setting and Mode of Treatment on Chondrocyte Viability

Ko, Seung Hee; Kim, Kee Soo; Choi, Yong Soo; Chung, Young Youl; Song, June Young; Park, Bong Hee; Choi, Jin Bae; Kim, Dae Joong; Kim, Yoon Sik; Lee, Jae Hyuk

Abstract

PURPOSE
The objective of this study was to investigate the effects of radiofrequency energy on human chondrocyte viability, and to correlate confocal laser microscopy fluorescence to sulfate uptake and to the histological integrity of articular cartilage. MATERIALS AND METHODS: The chondroplasty procedure for chondromalacic articular cartilage was performed using a 3.0-mm ArthroWand (Arthroscopic Electrosurgery System, ArthroCare Corporation) on fresh human articular cartilage. Radiofrequency energy was applied to the cartilage surface through the probe at a velocity of 10-mm per second in contact and non-contact mode. Three power settings were used. The treated cartilage was analyzed for chondrocyte viability by confocal laser microscopy and (35)S uptake. RESULTS: Confocal laser microscopy demonstrated partial-thickness chondrocyte death irrespective of treatment method. No mode of treatment or radiofrequency energy power setting resulted in full-thickness chondrocyte death. The depth of cartilage ablation was increased in the treated areas in contact mode in proportion to the power level and the time of treatment. No statistically significant difference in radiolabeled sulfate uptake of the specimens was observed with respect to the treatment modes and power settings. CONCLUSION: The extent of chondrocyte death by radiofrequency energy was not as significant as reported previously when the probe was moved at the speed of 10 mm/sec. Radiofrequency energy may be useful to treat chondromalacic cartilage in a contact mode using a proper energy level and delivery time.