Sonographic visualization and ultrasound-guided block of the third occipital nerve: prospective for a new method to diagnose C2-C3 zygapophysial joint pain

Anesthesiology. 2006 Feb;104(2):303-8. doi: 10.1097/00000542-200602000-00016.


Background: Chronic neck pain after whiplash injury is caused by cervical zygapophysial joints in 50% of patients. Diagnostic blocks of nerves supplying the joints are performed using fluoroscopy. The authors' hypothesis was that the third occipital nerve can be visualized and blocked with use of an ultrasound-guided technique.

Methods: In 14 volunteers, the authors placed a needle ultrasound-guided to the third occipital nerve on both sides of the neck. They punctured caudal and perpendicular to the 14-MHz transducer. In 11 volunteers, 0.9 ml of either local anesthetic or normal saline was applied in a randomized, double-blind, crossover manner. Anesthesia was controlled in the corresponding skin area by pinprick and cold testing. The position of the needle was controlled by fluoroscopy.

Results: The third occipital nerve could be visualized in all subjects and showed a median diameter of 2.0 mm. Anesthesia was missing after local anesthetic in only one case. There was neither anesthesia nor hyposensitivity after any of the saline injections. The C2-C3 joint, in a transversal plane visualized as a convex density, was identified correctly by ultrasound in 27 of 28 cases, and 23 needles were placed correctly into the target zone.

Conclusions: The third occipital nerve can be visualized and blocked with use of an ultrasound-guided technique. The needles were positioned accurately in 82% of cases as confirmed by fluoroscopy; the nerve was blocked in 90% of cases. Because ultrasound is the only available technique today to visualize this nerve, it seems to be a promising new method for block guidance instead of fluoroscopy.

Publication types

  • Randomized Controlled Trial
  • Research Support, Non-U.S. Gov't

MeSH terms

  • Adult
  • Anesthetics, Local
  • Arthralgia / diagnosis*
  • Cross-Over Studies
  • Double-Blind Method
  • Female
  • Fluoroscopy
  • Humans
  • Male
  • Nerve Block*
  • Spinal Nerves / anatomy & histology
  • Spinal Nerves / diagnostic imaging*
  • Ultrasonography
  • Zygapophyseal Joint*


  • Anesthetics, Local