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Start free with EleplanLenz-Majewski hyperostotic dysplasia
ORPHA:2658Malformation syndrome
Also called Lenz-Majewski hyperostotic dwarfism · Lenz-Majewski syndrome
What it is
A rare primary bone dysplasia characterized by growth delay, generalized and progressive craniotubular hyperostosis, intellectual disability, distinct craniofacial appearance, dental anomalies, loose skin, and distal-limb anomalies.
Key facts
- Prevalence
- <1 / 1 000 000
- Age of onset
- Antenatal, Infancy, Neonatal
- Inheritance
- Autosomal dominant
- Classified as
- Malformation syndrome
Prevalence figures describe populations, not individuals, and are often estimates from a single study. Where the figure is an incidence or a birth prevalence, it says so.
Signs and symptoms
Very common80–99%
30- Abnormal cortical bone morphology
- Abnormality of dental enamel
- Abnormal metaphysis morphology
- Aplasia/Hypoplasia of the skin
- Aplastic clavicles
- Brachydactyly
- Broad forehead
- Choanal atresia
- Cranial hyperostosis
- Delayed cranial suture closure
- Delayed skeletal maturation
- Facial hyperostosis
- Finger syndactyly
- Global developmental delay
- Hypertelorism
- Increased bone mineral density
- Intellectual disability
- Joint hypermobility
- Large fontanelles
- Macrocephaly
- Macrotia
- Mandibular prognathia
- Osteopetrosis
- Prematurely aged appearance
- Redundant skin
- Severe short stature
- Short palm
- Specific learning disability
- Symphalangism affecting the phalanges of the hand
- Thickened calvaria
Common30–79%
13Sometimes5–29%
15- Absent septum pellucidum
- Agenesis of corpus callosum
- Bifid uvula
- Cleft palate
- External genital hypoplasia
- High, narrow palate
- Hydrocephalus
- Hyperconvex fingernails
and 7 more in this range
These ranges are how often a sign appears across everyone diagnosed, not a prediction for one person — most people have some of these and not others. Orphanet also records findings that are specifically absent in this disease; those are in the data but not listed here.
Gene
ICD-10 codes
ICD-10 has no distinct code for most rare diseases, so many are filed under the nearest available one. A shared code identifies the group, not this disease — the ORPHAcode above is what identifies it.
Related health topics
Reached through the ICD-10 categories this disease is filed under, so these describe the broader group rather than this disease specifically.
Cross-references
Orphadata Science: Free access data from Orphanet. © INSERM 1999. Data version 2026-06-23. Available under CC BY 4.0. This is a reference, not medical advice.
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