A Histological Examination of the Lumbar Sympathetic Trunk

Current anatomical and histological descriptions of the lumbar sympathetic trunk suggest that its neuronal cell bodies are located in discrete ganglia linked to each other by nerve fibres. Despite well-documented variations in the morphology of the lumbar sympathetic trunk (e.g., number and placement of ganglia), a detailed histological examination of the arrangement of neuronal cell bodies within the trunk is lacking. Thus, the present study aims to examine the microscopic organization of the lumbar sympathetic trunk using standard histological techniques (n=1). A 95mm length of the sympathetic trunk (from L3-L5) was serially-sectioned (5μm thick) in the longitudinal plane and stained with Hematoxylin & Eosin to visualize the location of neuronal cell bodies. Neurons were present in 94/95mm of the trunk with the average millimeter containing 1832 neurons. The presence of neurons throughout the “interganglionic” space may have implications for future investigations of sympathetic activity and functional deficits in this region.