SMA is spinal muscular atrophy, the main symptoms are symmetric muscle weakness, progressive aggravation, proximal is heavier than distal, lower limbs are heavier than upper limbs, some patients are accompanied by tongue tremor, hand tremor, tendon reflexes are weakened or disappeared, etc. Specific subtypes are different, the manifestations are slightly different, including types I~IV.
1. Type I: the age of onset is usually less than 6 months, manifested by progressive proximal symmetrical muscle weakness, facial symptoms are usually reduced, and respiratory and swallowing difficulties are severe.
2. Type II: It usually occurs between the age of half and one and a half years, and is characterized by hypotonia, scoliosis, joint contractures, and respiratory muscle weakness.
3. Type III: The age of onset is usually one and a half years old. It is mainly characterized by unsteady gait when walking, frequent falls and difficulty in walking.
4. Type IV: The age of onset is between 20 and 30 years old. It usually manifests mild muscle weakness and does not affect the respiratory and digestive systems.
Therefore, patients with spinal muscular atrophy should seek prompt medical attention and early treatment to avoid delaying their condition.