Complete absence of the posterior arch of C1: Case report

R. Khanna, Z. A. Smith, B. J. Dlouhy, N. S. Dahdaleh*

*Corresponding author for this work

Research output: Contribution to journalArticlepeer-review

4 Scopus citations


Posterior atlas arch anomalies are relatively common, but have a variety of presentations ranging from partial clefts to complete agenesis of the posterior arch. Partial clefts are prevalent in 4% of patients and are generally asymptomatic. However, complete agenesis of the posterior arch is extremely rare. We report the case of a 46-year-old man who presented with upper cervical spine and occipital pain as well as left sided headaches. Imaging revealed congenital complete absence of the posterior arch of C1 (Type E) without any radiographic evidence of instability. We discuss our case in light of other reported cases and detail its management.

Original languageEnglish (US)
Pages (from-to)176-178
Number of pages3
JournalJournal of Craniovertebral Junction and Spine
Issue number4
StatePublished - Oct 1 2014


  • Agenesis
  • C1
  • atlantoaxial instability
  • bracing
  • posterior atlas arch

ASJC Scopus subject areas

  • Clinical Neurology
  • Surgery


Dive into the research topics of 'Complete absence of the posterior arch of C1: Case report'. Together they form a unique fingerprint.

Cite this