Which Approach to Favor for Ultrasound-guided Lumbar Plexus Block (BPLE). Comparative Study.

"Analysis lumbar echographies results by Trident ans Shamrock techniques.~Costiform processes on T12 to L5 were spotted and noted. For Trident technique, quality of image, depth of lumbar plexus and presence of vessels were noted.~Shamrock technique was performed, the projection of C line (line obtained with a probe put on the iliac crest) was noted with the invisible ink pen. Then the probe was oriented cephalically (for line \>C) and caudally (line \<C). For each lines, quality of image, depth of lumbar plexus and presence of vessels were also noted.~The projections of C, \>C, \<C on the costiform processes were noted."