The Effect of MonopolarRadio frequency Energy on Articular Cartilage
The Effect of MonopolarRadio frequency Energy on Articular Cartilage
abstract & Commentary
Synopsis: This paper challenges previous reports regarding the beneficial effects of the use of radiofrequency to treat articular cartilage injuries. Monopolar radiofrequency energy caused long-term damage to cartilage in an animal model.
Source: Lu Y, et al. The effect of monopolar radiofrequency energy on partial-thickness defects of articular cartilage. Arthroscopy 2000;16(5):527-536.
In a well-designed study using a sheep model, 36 animals (bilateral knees) were randomized into three groups: 1) untreated partial thickness cartilage injury (Sham); 2) radiofrequency (RF)-treated partial thickness cartilage injury; and 3) partial thickness cartilage injury converted to a full thickness defect with microfracture. Six knees from each group were studied at 0, 2, 12, and 24 weeks after surgery. Carefully obtained cartilage samples were studied by light microscopy, conofocal laser microscopy, and scanning electron microscopy for chondrocyte viability, thickness of reparative tissue, staining, and structure of reparative tissue at each time period.
In the untreated group, almost all of the chondrocytes remained viable at all time periods. In the RF-treated group, a zone of chondrocyte death was present at time zero, and this zone expanded at subsequent intervals and persisted the entire length of the study. Scanning electron microscopy demonstrated a smoother surface in the RF-treated group; however, this was felt to be related to a melting effect. The total histologic score was significantly higher for the untreated group vs. the RF group at all time periods. The microfracture group was associated with defects that predictably filled in with fibrocartilage, resulting in total histologic scores that were significantly higher than the RF group at all intervals except time zero. Staining demonstrated that RF caused detrimental effects to chondrocyte function and the cartilaginous matrix.
Comment by Mark Miller, MD
This study is one of the first published papers to advocate caution in face of the raging popularity of indiscriminate use of RF for any problem identified with the arthroscope. It is interesting that two of the researchers are among the most widely recognized proponents of laser and RF treatment; therefore, careful consideration of their findings is critical. Legitimate scientific studies are only now defining a reasonable role for RF "shrinkage." Extending indications for what may turn out to be a limited role for this new technology before it can be carefully evaluated in studies like the present paper is clearly inappropriate. I suspect that studies of RF-treated meniscal tears may yield similar discouraging effects on adjacent soft tissue.
As Lu and associates acknowledge, longer term studies are indicated. They also are aware of some of the limitations of their study, such as the variable depth of cartilage in the sheep model, the relative inprecision of their cartilage cutter, and the limited histologic evaluation that was completed. Nevertheless, this study shows that RF has a lasting detrimental effect on healthy articular cartilage.
Subscribe Now for Access
You have reached your article limit for the month. We hope you found our articles both enjoyable and insightful. For information on new subscriptions, product trials, alternative billing arrangements or group and site discounts please call 800-688-2421. We look forward to having you as a long-term member of the Relias Media community.