Spinal muscular atrophy (SMA) type II is a genetic neuromuscular disorder characterized by degeneration of motor neurons in the spinal cord and lower brain stem. It typically presents between 6 to 18 months of age with progressive muscle weakness, hypotonia, and tremors. Patients with SMA II do not achieve standing but can sit independently. The disease is caused by mutations in the SMN1 gene and is inherited in an autosomal recessive manner. Symptoms include respiratory issues and reduced life expectancy. Therapeutic strategies focus on managing symptoms and genetic testing is used for diagnosis.