Spastic paraplegia 3

From WikiMD's Wellness Encyclopedia

Alternate names[edit | edit source]

SPG3A; SPG3; Strumpell disease

Definition[edit | edit source]

A rare, pure or complex subtype of hereditary spastic paraplegia, with highly variable phenotype, typically characterized by childhood-onset of minimally progressive, bilateral, mainly symmetric lower limb spasticity and weakness, associated with pes cavus, diminished vibration sense, sphincter disturbances and/or urinary bladder hyperactivity. Additional associated manifestations may include scoliosis, mild intellectual disability, optic atrophy, axonal motor neuropathy and/or distal amyotrophy.

Cause[edit | edit source]

Mutations in the ATL1 gene cause spastic paraplegia type 3A.[1][1].


Inheritance[edit | edit source]

Autosomal dominant pattern, a 50/50 chance.

Spastic paraplegia type 3A is inherited in an autosomal dominant pattern.

Signs and symptoms[edit | edit source]

Spastic paraplegia 3A (SPG3A; also known as ATL1-HSP) is characterized by slowly progressive bilateral and mostly symmetric spasticity and weakness of the legs, and with a variable degree of diminished vibration sense (caused by degeneration of the corticospinal tracts and dorsal columns) and urinary bladder hyperactivity.

For most diseases, symptoms will vary from person to person. People with the same disease may not have all the symptoms listed. 80%-99% of people have these symptoms

30%-79% of people have these symptoms

  • Ankle clonus(Abnormal rhythmic movements of ankle)
  • Distal lower limb amyotrophy
  • Spastic gait(Spastic walk)

5%-29% of people have these symptoms

  • Hypoplasia of the corpus callosum(Underdevelopment of part of brain called corpus callosum)
  • Impaired vibratory sensation(Decreased vibration sense)
  • Intellectual disability, mild(Mental retardation, borderline-mild)
  • Motor delay
  • Toe walking(Toe-walking)
  • Urinary urgency(Overactive bladder)

1%-4% of people have these symptoms

Diagnosis[edit | edit source]

The diagnosis of ATL1-HSP is established in a proband with suggestive findings and almost exclusively a heterozygous pathogenic variant in ATL1 identified by molecular genetic testing.[2][2].


Treatment[edit | edit source]

  • Treatment is symptomatic.
  • Medical treatment of spasticity may begin with oral baclofen or tizanidine, followed by chemodenervation with botulinum A or B toxins if oral antispasticity medications are not tolerated.
  • Intrathecal baclofen pump may be considered for those who improve on oral baclofen but have significant systemic adverse effects.
  • Medical therapy should be combined with intensive physical therapy focused on stretching and strengthening exercises that may help delay or minimize muscle tendon contractures, scoliosis, and foot deformities.
  • Distal weakness (typically affecting foot dorsiflexion) can be ameliorated by ankle-foot orthoses.
  • Urinary urgency can be treated with anticholinergic antispasmodic drugs.[3][3].


  1. Hedera P. Spastic Paraplegia 3A. 2010 Sep 21 [Updated 2020 Jun 18]. In: Adam MP, Ardinger HH, Pagon RA, et al., editors. GeneReviews® [Internet]. Seattle (WA): University of Washington, Seattle; 1993-2021. Available from: https://www.ncbi.nlm.nih.gov/books/NBK45978/
  2. Hedera P. Spastic Paraplegia 3A. 2010 Sep 21 [Updated 2020 Jun 18]. In: Adam MP, Ardinger HH, Pagon RA, et al., editors. GeneReviews® [Internet]. Seattle (WA): University of Washington, Seattle; 1993-2021. Available from: https://www.ncbi.nlm.nih.gov/books/NBK45978/
  3. Hedera P. Spastic Paraplegia 3A. 2010 Sep 21 [Updated 2020 Jun 18]. In: Adam MP, Ardinger HH, Pagon RA, et al., editors. GeneReviews® [Internet]. Seattle (WA): University of Washington, Seattle; 1993-2021. Available from: https://www.ncbi.nlm.nih.gov/books/NBK45978/


NIH genetic and rare disease info[edit source]

Spastic paraplegia 3 is a rare disease.


Spastic paraplegia 3 Resources

Contributors: Deepika vegiraju