This site is intended for healthcare professionals

Go to /sign-in page

You can view 5 more pages before signing in

Kugelberg-Welander disease

Last reviewed dd mmm yyyy. Last edited dd mmm yyyy

Authoring team

SMA type 3

  • juvenile spinal muscular atrophy is an uncommon autosomal recessive disorder of the lower motor neurones
  • onset occurs between 2 and 17 years. It is characterised by wasting and weakness of proximal limb muscles. The deep tendon reflexes are decreased or absent. Fasciculations of the tongue may be occur
    • children and adults with type 3 SMA, also referred to as Kugelberg-Welander disease, are able to walk unassisted at some point during their lifetime
    • present with progressive proximal weakness of the legs more than the arms
    • leg weakness may necessitate the need of a wheelchair at some point

  • unlike, type 2, these individuals are mostly spared the comorbities of scoliosis and have little or no respiratory muscle weakness

  • cognition and life expectancy are not altered in this group


  • term spinal muscular atrophy (SMA) refers to a group of genetic disorders all characterized by degeneration of anterior horn cells and resultant muscle atrophy and weakness
    • most common SMA, accounting for over 95% of cases, is an autosomal recessive disorder that results from a homozygous deletion or mutation in the 5q13 survival of motor neuron (SMN1) gene
  • clinical severity of SMA correlates inversely with SMN2 gene copy number and varies from an extreme weakness and paraplegia of infancy to a mild proximal weakness of adulthood


  • Sugarman EA, et al. Pan-ethnic carrier screening and prenatal diagnosis for spinal muscular atrophy: clinical laboratory analysis of >72,400 specimens. Eur J Hum Genet. 2012; 20(1):27–32.
  • Kolb JS, Tissel SpinalJT. Muscular Atrophy. Neurol Clin. 2015 November ; 33(4): 831–846.

Related pages

Create an account to add page annotations

Add information to this page that would be handy to have on hand during a consultation, such as a web address or phone number. This information will always be displayed when you visit this page

The content herein is provided for informational purposes and does not replace the need to apply professional clinical judgement when diagnosing or treating any medical condition. A licensed medical practitioner should be consulted for diagnosis and treatment of any and all medical conditions.


Copyright 2024 Oxbridge Solutions Limited, a subsidiary of OmniaMed Communications Limited. All rights reserved. Any distribution or duplication of the information contained herein is strictly prohibited. Oxbridge Solutions receives funding from advertising but maintains editorial independence.