The main objective of the trial is to complete a double-blinded randomized controlled trial
with crossover design of a lumbosacral plexus block with the Suprasacral Parallel Shift
technique guided by ultrasound/magnetic resonance (MR) image fusion vs. Suprasacral Parallel
Shift guided by ultrasound by estimating sensory block of the femoral nerve, the obturator
nerve, the lumbosacral trunk, and spinal nerve L1 in healthy volunteers.