Greater Occipital Nerve Block

Landmarks
1. External occipital protuberance
  1. Midline occipital highest point (inion) on the posterioroinferior occiput of the skull
  2. Insertions for both the nuchal ligament and the trapezius
2. Mastoid process
  1. Posterior to the external acoustic meatus
3. Draw a line between the External occipital protuberance and Mastoid Process
  1. Greater Occipital Nerve lies 2/3 along the line, closer to the occiput
  2. Lesser Occipital Nerve lies 1/3 along the line, closer to the mastoid process
Greater Occipital Nerve injection site
1. Locate the External occipital protuberance (see above)
2. Injection site lies 2 cm lateral and 2 cm inferior to the protuberance
3. Injection site is also a prominence in the skull, and is often identified as a point of maximal tenderness
4. Injection site is immediately medial to the palpable occipital artery
Precaution
1. Ultrasound guided Occipital Nerve Block has replaced landmark-based injection in some centers
  1. https://www.nysora.com/pain-management/ultrasound-guided-greater-occipital-nerve-block/

Prepare the site
1. Identify landmarks and mark the injection site
2. Move hair from area (e.g. with assistant or lubricating jelly can be applied)
3. Clean the area (e.g. Hibiclens, Betadine, or Alcohol)
4. Consider Vapocoolant Spray first
Injection
1. Insert the needle from inferior approach
  1. Angle approximately 30-45 degrees and insert until striking periosteum
2. Aspirate for blood and if found, withdraw and redirect needle (to prevent intravascular injection)
3. Inject a total of 2-3 cc of Marcaine at site, distributing in a fan-shaped distribution
Observe
1. Reevaulate patient in 15 minutes after injection to assess effect