Ultrasound-Guided Lumbar Plexus Injection: A Cadaveric Validation.

Area of Science:

• Anatomy
• Pain Management
• Medical Imaging

Background:

• Ultrasound (US) is increasingly used for axial spine evaluation.
• Its accuracy for superficial structures is established, but evidence for deeper targets like the lumbar plexus is limited.

Purpose of the Study:

• To assess the feasibility of ultrasound-guided lumbar plexus injection.
• To evaluate dye spread patterns following injection at L3 and L4 nerve roots.

Main Methods:

• A cadaveric study using a fresh-frozen female specimen.
• Ultrasound-guided injection with a 2-5 MHz transducer and a 20-gauge spinal needle.
• Delivery of 5 mL green dye targeting L3 and L4 nerve roots with in-plane approach.

Main Results:

• Dissection confirmed L3 injection spread dye to the extraforaminal region.
• L4 injection showed anterior dye distribution adjacent to the intervertebral foramen.
• Acoustic shadowing from articular processes limited visualization.

Conclusions:

• Ultrasound-guided lumbar plexus injection is feasible.
• The technique shows potential for clinical pain management applications.
• Further validation with larger sample sizes is warranted.