(Netter Basic Science) Frank H. Netter - Atlas of Human Anatomy-Elsevier (2018)

Atlantooccipital Junction
2
Vertebral artery
Posterior margin
of foramen magnum
Posterior atlantooccipital
membrane
Posterior arch of atlas (C1)
Nuchal ligament
Posterior atlantoaxial membrane
Spinous process of axis (C2)
Ligamentum flavum
Hypoglossal canal
Tectorial membrane
Apical ligament of dens
Superior longitudinal band of
cruciate ligament of atlas
Anterior atlantooccipital membrane
Anterior arch of atlas (C1)
Articular cavity
Dens of axis (C2)
Transverse ligament of atlas
Inferior longitudinal band of
cruciate ligament of atlas
Anterior longitudinal ligament
Posterior longitudinal ligament
Posterior nasal spine
Lowest
level of
occipital bone
McGregor’s line, from posterior nasal spine of
hard palate to lowest point of occipital bone.
Average normal position of tip of dens is 1.32 mm
above this line, with standard deviation of 2.6 mm
as measured on standard lateral radiograph. Tip 4.5 mm
above line is considered to indicate basilar impression.
Abnormalities of dens, most
often associated with skeletal
dysplasias such as Klippel-Feil,
Down, or Morquio syndromes
Hypoplastic dens
Os odontoideum with fibrous union and narrowing of
vertebral canal with head in extension
Electronic Bonus Plates
mebooksfree.com
Plate BP19