Intraneural injections and regional anesthesia: the known and the unknown

Minerva Anestesiol. 2011 Jan;77(1):54-8.


Peripheral nerve injury is a rare complication of regional anesthesia. Intraneural injections were once considered harbingers of neural injury with practitioners focusing on their avoidance. With ultrasound guidance, it is now possible to visualize the difference between perineural (outside the nerve), intraneural (below the epineurium), and intrafascicular (within the perineurium) injections and to determine their association with postoperative neurological complications. We also now have a better understanding of the multifactorial nature of neurologic injury based on the nerve anatomy, site of needle insertion, bevel type, location of the needle tip, pressure achieved during injection, and underlying patient factors. Using ultrasound guidance during nerve blocks has revealed that not all intraneural injections result in injury, and its use will continue to provide insight into the mechanism of anesthetic-related nerve injury.

Publication types

  • Review

MeSH terms

  • Anesthetics, Local / administration & dosage
  • Anesthetics, Local / adverse effects*
  • Animals
  • Brachial Plexus Neuropathies / etiology
  • Dogs
  • Electric Stimulation
  • Equipment Design
  • Humans
  • Needles
  • Needlestick Injuries / diagnostic imaging
  • Needlestick Injuries / etiology*
  • Needlestick Injuries / pathology
  • Nerve Block / adverse effects*
  • Nerve Block / instrumentation
  • Peripheral Nerve Injuries*
  • Peripheral Nerves / diagnostic imaging
  • Peripheral Nerves / drug effects
  • Peripheral Nerves / ultrastructure
  • Postoperative Complications / etiology
  • Postoperative Complications / prevention & control
  • Rabbits
  • Rats
  • Sciatic Nerve / injuries
  • Ultrasonography


  • Anesthetics, Local