Brachial plexus root injection in a human cadaver model: injectate distribution and effects on the neuraxis.

Background: The potential for injection into the brachial plexus root at cervical levels must be considered during interscalene block or chronic pain interventions in the neck, but this phenomenon has not been well studied. In this investigation, we performed injections into the brachial plexus roots of unembalmed cadavers, with real-time ultrasound guidance, to evaluate the proximal and distal spread of the injected fluids, the potential of the injectate to reach the neuraxis, and whether the injectate could migrate into the actual substance of the spinal cord itself.

Methods: A solution of particulate dye mixed with local anesthetic was injected into 8 brachial plexus roots at a lower cervical level, in unembalmed cadaver specimens, utilizing an automated pump and pressure monitor.