Effects of Bipolar Radiofrequency on the Human Meniscus: A Comparative Study Between Patients Younger and Older Than 40 Years Old (SS-45)

Abstract

Bipolar radiofrequency is frequently used in arthroscopic surgery. It provides excellent intraarticular hemostasis, debridement and shrinkage of soft tissues. Although extensively used in meniscal surgery, there are few studies that report the ultrastructural effect of bipolar radiofrequency on the human meniscus. Furthermore, it is not clear if there is any difference between applying the same amount of energy on younger versus older menisci. The main objective of our study was to evaluate the effects of bipolar radiofrequency applied to the human meniscus in 4 differents intensities and compare the results between patients younger and older than 40 y.o. Our study shows the effects of four different magnitudes of bipolar radiofrequency, commonly used in knee arthroscopic surgery: coagulation medium and high, vaporization intensities 5 and 7. Each magnitude was applied for 3 seconds on 30 human menisci resected from patients between 14 and 84 years old. The menisci were then divided in two groups: younger and older than 40 years old, and studied macroscopically, microscopically and by electronic microscopy. Thermal necrosis was found between m (D.S. 740) andμm from the meniscal surface, with an average of 1700μ0 and 4000 was significantly higher on the vaporization than the coagulation group (p < 0.001). We found significative differences between patients younger or older than 40 years old in groups zone 2 and 3 (zone 2 p=0.038 and zone 3 p=0.044) We concluded that although bipolar radiofrequency can cause deep necrosis (up to m) on the human meniscus, this effect depends on the magnitude of the μ4000 energy applied and is higher when we applied medium intensity in older patients. KEY WORDS: Radiofrequency – Knee arthroscopy – Meniscus.