The Effects of Radiofrequency Energy Treatment on Chondrocytes and Matrix of Fibrillated Articular Cartilage

Abstract

Background There is no consensus regarding the safety of radiofrequency energy treatment for chondroplasty. Hypothesis Use of a radiofrequency thermal probe will produce a dose-dependent detrimental effect on chondrocytes in a setting mimicking the arthroscopic procedure. Study Design Controlled laboratory study. Methods Paired patellae from 11 horses were fibrillated; one served as the control while the contralateral patella was treated with 20, 40, and 60 watts of radiofrequency energy for 4 minutes. Proteoglycan synthesis, proteoglycan degradation, and cell viability were measured. Explant histologic sections were scored for cellular characteristics, metachromatic matrix staining intensity, and tissue architecture and were quantitatively analyzed for cell death. Results Mean peak surface articular cartilage temperatures were 35.47°C (20 watts), 40.76°C (40 watts), and 44.81°C (60 watts). Treatment at all three settings significantly decreased proteoglycan synthesis of the chondrocytes. Proteoglycan degradation increased with increased power setting. Treatment at 40 and 60 watts significantly decreased cell viability to 81% and 73%, respectively. Significant histologic changes occurred in the superficial cartilage zone with 60-watt application. Conclusion Use of radiofrequency energy on mechanically fibrillated articular cartilage induced a dose-dependent detrimental effect on chondrocytes and matrix metabolism. Clinical Relevance Cautious use of radiofrequency energy for treatment of articular cartilage is recommended until long-term effects are evaluated.