Ultrasound guided femoral blocks have been studied since the late 90's. A study published in 1997 by Marhofer et al. pointed that ultrasound guidance in a 3-in-1 block (femoral, obturator, lateral cutaneous nerves), improved the quality of the sensory block and reduced the onset time when compared with a nerve-stimulation technique in patients undergoing hip surgery after trauma.(13) In a meta-analysis comparing ultrasound guidance versus electrical nerve-stimulation for peripheral nerve blocks, the authors reported a decreased risk of block failure, shorter procedure time and faster onset time when ultrasound is used.(14)