46 Lumbar Sympathetic Block
Placement
Anatomy
The lumbar sympathetic chain, with its accompanying ganglia, is located in the fascial plane immediately anterolateral to the lumbar vertebral bodies (Fig. 46-1). The sympathetic chain is separated from the somatic nerves by the psoas muscle and fascia. The lumbar regions L1, L2, and sometimes L3 provide white rami communicantes to the sympathetic chain, and all five lumbar vertebrae are associated with gray rami communicantes. These rami are longer in the lumbar region than in the thoracic region. This is anatomically important because it allows needle placement nearer the anterolateral border of the vertebral body in the lumbar region. Conceptually, the anatomy important to anesthesiologists performing lumbar sympathetic nerve block is also the anatomy important for celiac plexus nerve block.