Clinical efficacy of ultrasound-guided pulsed radiofrequency combined with ganglion impar block for treatment of perineal pain

Figure 1 Position of the puncture point on the skin. A: A steel wire was placed perpendicular to the plane of the probe; B: The surface of the skin overlapped, causing a “comet-tail” sign behind the steel wire and the puncture position of sacrococcygeal joint (SCJ) was deeper.