[Hypothesis concerning the anatomical basis of cauda equina syndrome and transient nerve root irritation after spinal anesthesia].

This research highlights a potential anatomical reason behind the formation of cauda equina syndrome and transitory radicular irritation following spinal anesthesia. The study examines the spinal features of two human male cadavers to gain insights into the complications caused by subarachnoid anesthesia.

Research Objectives and Methods

• The primary objective of this research was to identify any anatomical factors that might obstruct the adequate dilution of the anesthetic, thereby contributing to the development of cauda equina syndrome and temporary radicular irritation.
• The researchers studied the spinal dura mater and their contents from two male human cadavers, both of whom had recently died in their mid to late adulthood.
• These samples were then processed by fixation in a glutaraldehyde phosphate buffer and dehydration in acetone before the acetone was eliminated via critical point elimination.
• The preserved samples were metallized with gold for enhanced visibility under a scanning electron microscope.

Findings

• The research revealed a differential structure of the arachnoid, with parts being more compact and others being lax.
• The compact portion was characterized by a laminar structure created by the fusion of fibers and cellular components lining the inner layer of the dura mater.
• On the other hand, the lax portion appeared as a network of weblike filaments and fewer cellular bodies, extending from the compact inner arachnoid layer to the cellular plane of the pia mater.
• The lax portion also dispersed compact arachnoid projections, named “arachnoid sheaths” by the researchers, that enveloped structures within the subarachnoid space. This potentially has implications for the dispersion and dilution of anesthetic injected into this area.

Relevance

• The findings of this study provide important insights into the anatomical makeup of the spinal arachnoid and its implications for the effective implementation of spinal anesthesia.
• Understanding these anatomical structures may help professionals mitigate potential complications, including cauda equina syndrome and radicular irritation, associated with such procedures.