The efficacy of two electrodes radiofrequency technique: comparison study using a cadaveric interspinous ligament and temperature measurement using egg white.

BACKGROUND One technique in radiofrequency neurotomies uses 2 electrodes that are simultaneously placed to lie parallel to one another. Comparing lesions on cadaveric interspinous ligament tissue and measuring the temperature change in egg white allows us to accurately measure quantitatively the area of the lesion. METHODS Fresh cadaver spinal tissue and egg white tissue were used. A series of samples were prepared with the electrodes placed 1 to 7 mm apart. Using radiofrequency, the needle electrodes were heated in sequential or simultaneous order and the distance of the escaped lesion area and temperature were measured. RESULTS Samples of cadaver interspinous ligament showed sequential heating of the needles limits the placement of the needle electrodes up to 2 mm apart from each other and up to 4 mm apart when heated simultaneously. The temperature at the escaped lesion area decreased according to the distance for egg white. There was a significant difference in temperature at the escaped lesion area up to 6 mm apart and the temperature was above 50 degrees celsius up to 5 mm in simultaneous lesion and 3 mm in the sequential lesion. LIMITATIONS The limitations of this study include cadaveric experimentation and use of intraspinous ligament rather than medial branch of the dorsal ramus which is difficult to identify. CONCLUSION Heating the 2 electrodes simultaneously appears to coagulate a wider area and potentially produce better results in less time.