Bipolar and Monopolar Radiofrequency Treatment of Osteoarthritic Knee Articular Cartilage –Acute and Temporal Effects on Cartilage Compressive Stiffness, Permeability, Cell Synthesis, and Extracellular Matrix Composition - Cook, James L.; Kuroki, Keiichi; Kenter, Keith; Marberry, Kevin; Brawner, Travis; Geiger, Timothy; Jayabalan, Prakash; Bal, B. Sonny (The Journal of Knee Surgery, 2004)