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Start free with EleplanSchwartz-Jampel syndrome
ORPHA:800Disease
Also called Aberfeld syndrome · Burton skeletal dysplasia · Burton syndrome · Catel-Hempel syndrome · Dysostosis enchondralis metaepiphysaria, Catel-Hempel type · Myotonic chondrodystrophy · Myotonic myopathy, dwarfism, chondrodystrophy, ocular and facial anomalies · Osteochondromuscular dystrophy · SJS · SJS1 · Schwartz-Jampel syndrome type 1 · Schwartz-Jampel-Aberfeld syndrome
What it is
A rare, genetic neuromuscular disease characterized by permanent myotonia, mask-like facies (with blepharospasm, narrow palpebral fissures, small mouth with pursed lips and puckered chin) , and chondrodysplasia (variably manifesting with short stature, pectus carinatum, kyphoscoliosis, bowing of long bones, epiphyseal, metaphyseal, and hip dysplasia).
Key facts
- Prevalence
- <1 / 1 000 000
- Age of onset
- Infancy, Neonatal
- Inheritance
- Autosomal recessive
- Classified as
- Disease
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%
26- Abnormality of epiphysis morphology
- Abnormal metaphysis morphology
- Arthrogryposis multiplex congenita
- Bowing of the long bones
- Elevated circulating aldolase concentration
- Elevated circulating creatine kinase concentration
- EMG abnormality
- Everted lower lip vermilion
- Full cheeks
- Gait disturbance
- Genu valgum
- Hip dysplasia
- Hypertonia
- Intellectual disability
- Joint stiffness
- Metatarsus valgus
- Micromelia
- Myotonia
- Narrow mouth
- Pes planus
- Posteriorly rotated ears
- Pursed lips
- Short stature
- Skeletal dysplasia
- Trismus
- Visual impairment
Common30–79%
33- Abnormal eyebrow morphology
- Abnormality of the pharynx
- Abnormally high-pitched voice
- Abnormally ossified vertebrae
- Blepharophimosis
- Cataract
- Coxa valga
- Coxa vara
- Flat face
- Flexion contracture of toe
- High palate
- Hip contracture
- Hyperlordosis
- Hyporeflexia
- Kyphosis
- Mask-like facies
- Micrognathia
- Myopathy
- Myopia
- Osteoporosis
- Overfolded helix
- Pectus carinatum
- Platyspondyly
- Prominent nasal bridge
- Ptosis
- Scoliosis
- Short neck
- Shoulder flexion contracture
- Skeletal muscle hypertrophy
- Spinal rigidity
- Strabismus
- Weak voice
- Wrist flexion contracture
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.
Benefit programs to look at
Programs whose eligibility touches the same ICD-10 categories. Eligibility is decided by the administering agency, never by this page.
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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