Paravertebral block of the lumbar plexus. Variations of the original technic

Abstract After studying a hundred or so abdominal CT scans carried out at L5 level and having verified that the interfascial compartment between the quadrate muscle of the lumbi and the psoas muscle is relatively fixed (1.8-2.3 cm), it is proposed to utilise this datum (introduction of the 2 cm) needle after contact with the transverse apophysis of L5) to identify the psoas compartment which contains most of the nerves making up the lumbar plexus. Study of the series and results obtained confirm the value and simplicity of the proposed technique.