Human lumbar sympathetic blockade: An anatomical study to address potential block failure

Area of Science:

• Anatomy
• Pain Management
• Interventional Radiology

Background:

• Lumbar sympathetic blocks are a common treatment for complex regional pain syndrome.
• High failure rates suggest a need to optimize the procedure.

Purpose of the Study:

• To investigate anatomical variations influencing lumbar sympathetic block success.
• To refine the lumbar sympathetic block technique based on anatomical findings.

Main Methods:

• Simulated lumbar sympathetic trunk blocks performed on unembalmed human cadavers (n=4).
• Injections at L2 and L4 vertebral body levels under fluoroscopic guidance, followed by dye injection and dissection.
• Comparison of dye spread with fluoroscopic contrast medium distribution.

Main Results:

• Significant anatomical variations in sympathetic ganglia location were observed across vertebral levels and individuals.
• Dye spread patterns highlighted potential inaccuracies in targeting with traditional methods.
• The L4 vertebral level demonstrated a more consistent anatomical target.

Conclusions:

• Anatomical variability is a key factor in lumbar sympathetic block failure.
• A refined technique using an extraforaminal approach at the L4 vertebral level is recommended.
• This optimized approach aims to improve the efficacy of lumbar sympathetic blocks for pain management.