Synonyms: Intermediate spinal muscular atrophy | SMA type 2 | SMA type II | SMA-II | SMA2
A rare genetic proximal spinal muscular atrophy characterized by degeneration of alpha motor neurons in the anterior horns of the spinal cord and lower brain stem manifesting with onset between 6 to 18 months of age with progressive proximal muscle weakness mild to moderate hypotonia and finger polymyoclonour tremor with areflexia. Motor milestones are classically limited to independent sitting or standing.
Data from Orphanet are used to provide information on a disease's name, synonym(s), and overview. Reference: Access aggregated data from Orphanet at Orphadata. Orphadata: Free access data from Orphanet. © INSERM 1999. Available on http://www.orphadata.org. Data version March 2026
Newly diagnosed with
Proximal spinal muscular atrophy type 2?
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Advocacy Organizations
All India Institute of Medical Sciences ( AIIMS), New Delhi, India
Trinity of Care:Academic and Clinical
Association Aux Pas du Coeur – Côte d’ivoire
Our organization wants to raise awareness and recognition of rare diseases in Ivory Coast. Our mission is to: Raise awareness and campaign to help with the diagnosis and free therapeutic care of patients. Request and/or contribute to actions relating to the training of the medical profession to be able to make a final diagnosis and ensure continuous monitoring of patients easily.
Cookies4Cures
Funding research into rare pediatric diseases
Fighting for Kaiden Foundation
The Fighting for Kaiden Foundation is a non-profit organization committed to enhancing the lives of those struggling with Spinal Muscular Atrophy (SMA) on multiple fronts. Directly, we strive to raise awareness of the disease on the local, regional and national levels. Our foundation provides need-based financial support to affected families for equipment and travel. We understand the value of peer support and organize support groups and information for SMA affected families in our area. We provide directed donations for medical research in addition to medical equipment and services for SMA patients across the country. Our goals are driven by our devotion to improving the lives and finding a cure for those with SMA.
Fundacion Powerchair Football Argentina
To develop Powerchair Football in Argentina in order to integrate people with motor disabilities (SMA, Duchenne muscular dystrophy, Achondroplasia, Rare Diseases) into sports practice and to promote their social inclusion, based on empowerment, independence, and the creation of new bonds and friendships.
Miracle For Madison & Friends
Raise awareness for SMA , provide support to families and fund research for a treatment/cure
Neuromuscular Disease Foundation
The Neuromuscular Disease Foundation's (NDF) mission is to enhance the quality of the lives of people living with GNE Myopathy (also known as HIBM) through advocacy, education, outreach, and funding clinical research focused on treatments and a cure.
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Clinical Trials
For a list of clinical trials in this disease area, please click here.