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Start free with EleplanDistal myopathy, Welander type
ORPHA:603Disease
Also called WDM
What it is
A rare distal myopathy characterized by weakness in the distal upper extremities, usually finger and wrist extensors which later progresses to all hand muscles and distal lower extremity, primarily in toe and ankle extensors.
Key facts
- Prevalence
- >1 / 1000 (Sweden)
- Age of onset
- Adult
- 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
Very common80–99%
6These 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.
Genes
1 modifying gene — variants that can change how the disease behaves, not cause it
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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