Those with SMA type II, which is diagnosed before 18 months of age, are unable to stand or walk unaided, although they may be able to sit and may survive beyond age 4. [aetna.com]

LATE ADOLESCENCE/ ADULTHOOD (adult-onset) LATE ADOLESCENCE/ADULTHOOD (adult-onset) 1,2,4 Highest motor milestone achieved ALL Life expectancy (untreated SMA) NORMAL Clinical characteristics Physical symptoms are similar to late-onset SMA, with the gradual [togetherinsma-hcp.com]

Affected infants have hypotonia (often notable at birth), hyporeflexia, tongue fasciculations, and pronounced difficulty sucking, swallowing, and eventually breathing. [merckmanuals.com]

Patients typically present during infancy or early childhood with progressive weakness, hypotonia, muscle atrophy, hyporeflexia /areflexia, and varying degrees of bulbar weakness. [amboss.com]

Skeletal and intercostal muscles denervation lead to weakness, hypotony, hyporeflexia, respiratory failure, symmetric muscle atrophy and paralysis in patients with SMA. Manifestations are prominent in proximal muscle of lower extremities. [ijp.mums.ac.ir]

LMN signs include weakness, muscle wasting, hyporeflexia, muscle cramps, and fasciculations. In the early stage of the disease, the clinical aspects of ALS can vary. [aetna.com]

ankle reflexes and minimal or no sensory loss, sometimes mild proximal weakness in the legs and feet and hand deformities in males. [orpha.net]