Radiofrequency Controlled Ablation Technique for Arthroscopic Meniscectomy of the Knee

Abstract

Despite mixed responses in the literature regarding knee arthroscopies, radiofrequency (RF) ablation remains a preferred method for partial meniscectomy of the knee. This technique is believed to offer advantages over traditional shaving methods, such as reduced risk of long-term fissure propagation and enhanced precision. However, existing literature does not yield a conclusive status of RF's risk-benefit profile, contributing to a mixed response to its recognized utility and safety in the arthroscopic community. This article details a procedure for performing partial meniscectomy with RF ablation using a feedback-controlled bipolar RF device (WEREWOLF FLOW50 Wand; ArthroCare/Smith & Nephew, Austin, TX), with a focus on parameters that can influence intervention safety. These parameters include device-specific factors such as energy transmission type and field density, as well as surgeon-specific factors such as rest/shutoff time, translation speed, and instrumentation depth. Postoperative care typically involves physical therapy, emphasizing early mobilization and strengthening exercises to ensure optimal recovery. Although our clinic has observed positive results with feedback-controlled bipolar RF for partial meniscectomy, further studies are necessary to conclusively determine the risk-benefit profile of this technique, including long-term follow-up to assess durability and patient satisfaction. Additionally, comparisons with other techniques could provide a more comprehensive understanding of its efficacy and overall impact on patient outcomes.

Fig 1

Coronal-plane cut: anterior view of meniscal lesion in left knee via magnetic resonance imaging. The increased signal intensity, visible as white/cloudy content inside the dark triangle (arrow), identifies the lesion. (LFC, lateral femoral condyle.)

Fig 2

Sagittal-plane cut: lateral view of meniscal lesion in left knee via magnetic resonance imaging. The increased signal intensity, visible as white/cloudy content inside the dark triangle (arrow), identifies the lesion.

Fig 3

Arthroscopic anterior view of left knee via lateral portal showing wave lesion (WL) located on lateral meniscus (LM), as evidenced by superior translation of compromised tissue, creating shaded edge on posterior aspect. (LFC, lateral femoral condyle; TP, tibial plateau.)

Fig 4

Arthroscopic anterior view of left knee via lateral portal showing feedback-controlled bipolar radiofrequency ablation device (WEREWOLF FLOW50 Wand) (RF) inserted via medial portal in position near wave lesion (WL) and ready for instrumentation. Feedback-controlled bipolar devices are becoming the more dominant expression of arthroscopic radiofrequency ablation because their use reduces potentially harmful energy transference to viable adjacent tissue as compared with monopolar or bipolar devices. (LFC, lateral femoral condyle; LM, lateral meniscus.)

Fig 5

Arthroscopic anterior view of left knee via lateral portal showing feedback-controlled bipolar radiofrequency ablation device (WEREWOLF FLOW50 Wand) (RF) during initial stages of intervention. One should note the 1- to 3-mm distance between the probe tip and the target tissue, as well as no red flash at the end of the probe tip, signifying that the device is in the “shutoff” cycle. Minimal to no instances of direct contact and intermittent shutoff times of 1 to 3 seconds are recommended to reduce the risk of energy overexposure to the surrounding viable tissue. (LFC, lateral femoral condyle; LM, lateral meniscus; WL, wave lesion.)

Fig 6

Arthroscopic anterior view of left knee via lateral portal showing feedback-controlled bipolar radiofrequency ablation device (WEREWOLF FLOW50 Wand) (RF) progressing through intervention. One should note that the device has moved to another region of the target tissue, while the former target region (oval) is not fully ablated. This highlights another technique feature that limits energy overexposure, that is, the brush technique, oscillating over various portions of the target region with a translation speed of 1 to 3 mm/s. The device will oscillate over various target regions until the intervention is complete. (LFC, lateral femoral condyle; LM, lateral meniscus.)

Fig 7

Arthroscopic anterior view of left knee via lateral portal showing feedback-controlled bipolar radiofrequency ablation device (WEREWOLF FLOW50 Wand) (RF) returning back to original target site to complete ablation process for this region. One should note a red flash at the probe tip, signifying that the device is actively ablating tissue. Throughout the intervention, the device, turned on, creates a localized plasma field that ablates the target tissue through reactive plasma species bombardment. (LFC, lateral femoral condyle; LM, lateral meniscus; WL, wave lesion.)

Fig 8

Arthroscopic anterior view of left knee via lateral portal showing target region beginning to reach tissue smoothing phase (oval), observed by beginning changes in coloration of meniscal rim as compared with surrounding meniscal tissue. Tissue smoothing is the chondral matrix realignment that is proposed to reduce long-term fissure propagation potential. (LFC, lateral femoral condyle; LM, lateral meniscus; RF, feedback-controlled bipolar radiofrequency ablation device [WEREWOLF FLOW50 Wand].)

Fig 9

Arthroscopic anterior view of knee via lateral portal showing entire target region reaching satisfactory level of tissue smoothing (oval), which signals completion of procedure. The smoothed region can be observed by the increased yellowish discoloration along the meniscal rim as compared with the surrounding meniscal tissue. Tissue smoothing is a chondral matrix realignment that is proposed to reduce long-term fissure propagation potential. (LFC, lateral femoral condyle; LM, lateral meniscus; TP, tibial plateau.)