Temperature in and around the scapholunate ligament during radiofrequency shrinkage: a cadaver study

Articular cartilage and soft tissue damage from radiofrequency thermal ablation wands at wrist arthroscopy

We report six cases of complications from use of a thermal wand at wrist arthroscopy. Complications included skin necrosis, extensor tendon lesions and thermal articular cartilage damage, one with a catastrophic outcome. Thermal wands have the potential for substantial soft tissue damage causing severe harm to patients. The damage could be related to the design of the wands. User error poses an additional risk. These risks need to be appreciated and should be minimized. The complications indicate the need for careful use of the thermal wands to minimise risk including using only short bursts of thermal energy, the use of high flow irrigation with an outflow and trying to ensure that the collar of the device and not just the tip is within the joint. In addition, the design of thermal wands for use in the wrist may need to be reviewed.Level of evidence: IV.

Arthroscopic electrothermal collagen shrinkage for partial scapholunate ligament tears, isolated or with associated triangular fibrocartilage complex injuries: a prospective study

BACKGROUND

To present the outcomes of arthroscopic electrothermal shrinkage for partial scapholunate (SL) ligament tears, isolated or with associated triangular fibrocartilage complex (TFCC) injuries.

METHODS

A prospective study of 20 patients with symptomatic instability of SL ligament (14 of them also with TFCC wrist injuries) treated with arthroscopic electrothermal shrinkage was conducted using a monopolar radiofrequency probe. No patient showed radiologic signs of static dissociation (mean SL interval 2.2 ± 0.6 mm; mean SL angle 41.4° ± 6.7°) before surgery. All patients underwent follow-up at our clinic regularly for an average of 50.6 months (range 29-80 months).

RESULTS

The modified Mayo wrist score improved from a mean of 59 ± 17.1 points preoperatively to 88.3 ± 16.2 points at the final follow-up. At the final clinical examination, a painful Watson scaphoid shift test was found in 3 patients (15%). The mean flexion-extension arc was unchanged (132° ± 19°), and mean grip strength improved 12 kg. No patient showed radiologic signs of arthritis or instability after surgery (mean SL interval 1.9 ± 0.7 mm; mean SL angle 42.7° ± 7.3°). Of the 14 patients with combined TFCC injuries, 3 patients continued complaining of ulnar-sided point tenderness. At the end of the follow-up, 80% of the subjects were satisfied or very satisfied.

CONCLUSIONS

SL ligament and TFCC electrothermal shrinkage effectively provided pain relief and grip strength increase for most of the patients treated.

LEVEL OF EVIDENCE

Level IV.

Effects on the Distal Radioulnar Joint of Ablation of Triangular Fibrocartilage Complex Tears With Radiofrequency Energy

PURPOSE

This cadaver study investigated the temperature profile in the wrist joint and distal radioulnar joint (DRUJ) during radiofrequency energy (RFE) application for triangular fibrocartilage complex resection.

METHODS

An arthroscopic partial resection of the triangular fibrocartilage complex using monopolar and bipolar RFE was simulated in 14 cadaver limbs. The temperature was recorded simultaneously in the DRUJ and at 6 other anatomic locations of the wrist during RFE application.

RESULTS

The mean temperature in the DRUJ was 43.3 ± 8.2°C for the bipolar system in the ablation mode (60 W) and 30.4 ± 3.4°C for the monopolar system in the cut mode (20 W) after 30 seconds. The highest measured temperature in the DRUJ was 54.3°C for the bipolar system and 68.1°C for the monopolar system.

CONCLUSIONS

The application of RFE for debridement or resection of the triangular fibrocartilage complex in a clinical setting can induce peak temperatures that might cause damage to the cartilage of the DRUJ. Bipolar systems produce higher mean temperatures than monopolar devices.

CLINICAL RELEVANCE

RFE application increases the mean temperature in the DRUJ after 30 seconds to a level that may jeopardize cartilage tissue.