<unk>  is a rare type of cephalic disorder characterised by three common characteristics: a defect to the occipital bone, spina bifida of the cervical vertebrae and retroflexion (backward bending) of the head on the cervical spine. Stillbirth is the most common outcome, with a few rare examples of live birth, after which death almost invariably occurs within a short time. The disorder was first described by Étienne Geoffroy Saint-Hilaire in 1836. The name is derived from the Ancient Greek word ἰνίον inion, for the occipital bone/nape of the neck.
Iniencephaly
Klippel–Feil syndrome
Brachyphalangy
Microhydranencephaly
Oxycephaly
Hemihydranencephaly
Anencephaly
Hydranencephaly