Congenital Atlanto-Occipital Fusion and its Effect on the Myodural Bridge: A Case Report Utilizing the P45 Plastination Technique

The atlanto-occipital joint is composed of the superior fossa lateral masses atlas (C1) and occipital condyles. Congenital Atlanto-occipital fusion (AOF) involves osseous union base occiput (C0) (C1). AOF or occipitalization/assimilation represents a craniovertebral junction malformation (CVJM) which can be accompanied by other cranial spinal malformations. may asymptomatic patients experience symptoms from neural compression as well limited neck movement. myodural bridge (MDB) complex dense fibrous structure that connects suboccipital muscular its related facia to cervical dura mater, passing through both posterior atlanto-axial interspaces. It not known if occipitilization induce structural changes in MDB associated musculature. region cadaveric head specimen an 87-year-old Chinese male having congenital with resultant was observed. After being treated P45 plastination method, multiple slices obtained were examined special attention paid CVJM. malformations are defined partial complete In present case CVJM, unilateral left condyle mass C1 observed, central margin foramen magnum arch C1. Also noted variation course vertebral artery due narrowed interspace. Surprisingly, agenesis rectus capitis minor (RCPmi) obliques (OCS) muscles also observed plastinated slices. Interestingly, MDB, normally originates part RCPmi muscle, originate bifurcation within aspect nuchal ligament. Therefore, involving appear effective compensation