Temperature Requirements for Altering the Morphology of Osteoarthritic and Nonarthritic Articular Cartilage: In Vitro Thermal Alteration of Articular Cartilage

Background. Radiofrequency and laser thermal chondroplasty procedures are performed to debride and smooth fibrillated, articular cartilage. Hypothesis: Temperature requirements necessary to achieve morphological change will be lower in fibrillated arthritic cartilage as compared with nonarthritic articular cartilage. Study Design: Controlled laboratory study. Methods: A thermal cell-culture chamber was mounted on a stereoscopic microscope and coordinated with a custom temperature-control program. Nonarthritic and osteoarthritic articular cartilage specimens were sectioned into full-thickness slices. The articular sections were exposed to temperatures incrementally from 37°C to 75°C. Real-time, digital capture microscopy was used to visualize and analyze the morphological changes undergone by the articular cartilage specimens. Results: Arthritic articular cartilage displayed morphological change at 56.5 ± 1.7°C. Loss of fibrillation was the initial morphological change visualized. Continued thermal exposure caused a shrinkage effect of the entire tissue section that was similar to the change seen in nonarthritic sections. Nonarthritic cartilage displayed morphological change at 60.9 ± 1.9°C. Conclusions: Consistent characteristic morphological changes were found at distinct temperatures in osteoarthritic and nonarthritic articular cartilage. Clinical Relevance: This information begins to establish the thermal parameters required for morphological change of osteoarthritic articular cartilage.