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Temperature Requirements for Altering the Morphology of Osteoarthritic and Nonarthritic 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.