Humberto Gerardo Rosas MD, Presenter: Nothing to Disclose

Injury to the genitofemoral nerve and unsuccessful blockade of the lumbar sympathetic chain are the most common complications following lumbar sympathetic blocks (LSB). Prior studies have shown that conventional techniques lead to either anterior or lateral placement of the needle in respect to the sympathetic ganglia, or placement within the psoas muscle itself leading to suboptimal flow of the injectate. A transdiscal approach was recently advocated to avoid these complications, however the potential for discitis, and accelerated disc degeneration must be considered. The purpose of the study was to evaluate a new paradiscal, extraforaminal technique to perform fluoroscopically directed lumbar sympathetic blocks that would avoid transgression of vital structures and allow appropriate needle placement along the anterolateral aspect of the vertebral body.

IRB approval and a waiver of consent were obtained for this retrospective HIPAA compliant study. Fluoroscopic spot views and medical records from 73 (45 females, 28 males; mean age 46.3) consecutively performed lumbar sympathetic blocks dating back to March 13, 2008 were retrospectively reviewed. Patients meeting the diagnostic criteria for complex regional pain syndrome with symptoms lasting greater than 6 months refractory to conservative measures were included in the study. Utilizing the transverse process as a guide, the needle was advanced under fluoroscopic guidance to the anterolateral aspect of the vertebral body. Contrast was administered to confirm appropriate needle placement and skin surface temperatures monitored to document the sympathetic response. The response to the injection was determined utilizing a 10 point Visual Analog Score (VAS).

No major complications occurred defined as death, neurovascular injury, injury to the visceral organs, and infection. Minor complications included a single vasovagal response. All 73 injections resulted in a greater than 3oC increase in skin temperature indicating appropriate blockade of the sympathetic ganglia. VAS scores demonstrated a statistically significant reduction in symptoms from baseline to the postprocedure period.

This study describes a safe alternative method for performing LSB.

The technique described allows placement of the needle subjacent to the sympathetic ganglia while avoiding transgression of vital structures.

Rosas, H, Performing Lumbar Sympathetic Blocks: A New Technique.  Radiological Society of North America 2014 Scientific Assembly and Annual Meeting, - ,Chicago IL. http://archive.rsna.org/2014/14011159.html