The Sinuvertebral Nerve Revisited. A Morphological and Immunohistochemical Study
The study found that 85.4% of sinuvertebral nerves had a single branch, and all samples were positive for CGRP and VIP, which may inform future pain management strategies.
Where it sits
this study against the rest of the vip (vasoactive intestinal polypeptide) corpusSummary and findings
This study analyzed the sinuvertebral nerve (SVN) in 100 vertebral column segments from 10 adult cadavers, focusing on its morphological and immunohistochemical characteristics. The study found that 85.4% of the SVN presented a single branch, while 14.6% had two branches. All samples were positive for CGRP and VIP, indicating a sympathetic and nociceptive profile.
Abstract
The proven involvement of sinuvertebral nerve (SVN) in discogenic low-back pain and the demonstration that its blockade has been effective in reducing the intensity and frequency of diffuse low back pain have led to an increase in publications related to the characterization of this nerve. However, there is a huge disparity in the observations resulting from the studies carried out, probably due to the technical difficulty of accessing this structure. In the last years the number of studies in large samples has increased but some important data in relation to nature of sinuvertebral nerve remain unpublished. We studied 100 vertebral column segments between L1 and L5, corresponding to both sides of 10 adult cadavers donated to the Body Donation Center and Dissection Rooms of the Complutense University of Madrid. All levels were carefully dissected to study sinuvertebral nerve origins and some samples of SVN were selected to routinely paraffin-embedded and serially sectioned with a Minot-type microtome at a 7µm thickness. Immediately after dewaxing following the standard histology lab protocols, sections from selected SVN (well-preserved morphology and histologic condition) were subjected to an immunohistochemical protocol to detect CGRP-IH, and VIP-IH. Data analysis was performed using IBM SPSS Statistics version 27 and RStudio. The SVN was observed with a single branch (pattern I) in 82 cases (85.4%) and with two branches (pattern II) at the same level in 14 cases (14.6%).Statistical differences were not found in relation to vertebral levels, side or sex. All sinuvertebral nerve samples that underwent immunohistochemical study were positive for CGRP and VIP, demonstrating the sympathetic nature of the nerve (VIP+) and its nociceptive component (CGRP+). This study confirms the neurochemistry profile of the SVN thanks due to the realization of the immunochemistry characterization directly in the SVN, not in its innervated structures. This information supports the usage of the SVN blocking from a pathophysiological point of view for diagnostic and treatment techniques (e.g., Percutaneous Transforaminal Endoscopic Radiofrequency Ablation of the SVN) in discogenic lumbar pain.