Rare diseases · Sign or symptom
Prominent occiput
Prominent back of the skull
HP:0000269
What it means
Increased convexity of the occiput (posterior part of the skull).
Increased convexity of the occiput gives an appearance of prominence. There are no objective measures for convexity of the occiput, and evaluation depends heavily on the experience of the observer. This finding may or may not be accompanied by Dolichocephaly, but this should be coded separately.
Rare diseases that can present with this34
Very common80–99%
11- Blepharophimosis-intellectual disability syndrome, SBBYS type
- Cranioectodermal dysplasia
- Isolated Dandy-Walker malformation
- Isolated megalencephaly
- Linear nevus sebaceus syndrome
- Microcephalic osteodysplastic primordial dwarfism types I and III
- Mucolipidosis type III
- Osteogenesis imperfecta
- Paternal uniparental disomy of chromosome 6 syndrome
- Sporadic fetal brain disruption sequence
- Trisomy 18 syndrome
Common30–79%
12- 3C syndrome
- Acrocallosal syndrome
- Autosomal dominant spondylocostal dysostosis
- Beckwith-Wiedemann syndrome
- Delayed membranous cranial ossification
- FG syndrome type 1
- Hajdu-Cheney syndrome
- Lissencephaly syndrome, Norman-Roberts type
- Menkes disease
- Monosomy 22 syndrome
- Penoscrotal transposition
- Ulbright-Hodes syndrome
The range is how often this sign appears among people diagnosed with each disease — it is not a probability of having any of them. Many of these signs also occur in common, non-rare conditions. A sign on this page is a conversation to have with a clinician, not a conclusion.
Part of the broader category
Also called: Prominent back of the head · Prominent posterior cranium · Prominent posterior head · Prominent posterior skull · Protruding back of the head · Protruding occiput
Tracking symptoms like this for someone? Eleplan keeps symptoms, diagnoses, medications and every specialist in one plan.
Start free with EleplanThis page uses the Human Phenotype Ontology (2026-06-23) — Human Phenotype Ontology Consortium, hpo.jax.org. Disease associations from Orphanet (INSERM), CC BY 4.0. Content is educational and is not medical advice.