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Start free with EleplanAutosomal dominant adult-onset proximal spinal muscular atrophy
ORPHA:209335Disease
Also called Autosomal dominant adult-onset proximal SMA · Autosomal dominant late-onset spinal muscular atrophy, Finkel type · Finkel disease · SMAFK
What it is
A rare, genetic, motor neuron disease characterized by adulthood-onset of slowly progressive, proximal muscular weakness with fasciculations, amyotrophy, cramps, and absent/hypoactive reflexes, without bulbar or pyramidal involvement.
Key facts
- Prevalence
- 1-9 / 1 000 000 (Europe)
- Age of onset
- Adult, Elderly
- Inheritance
- Autosomal dominant
- 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
Common30–79%
9Sometimes5–29%
10- Calf muscle hypertrophy
- Elevated circulating creatine kinase concentration
- Joint stiffness
- Lower limb muscle weakness
- Myotonia
- Shuffling gait
- Talipes
- Tremor
and 2 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.
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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