What does SMA mean? Spinal Muscular Atrophy also is known as SMA is a medical term. It is a kind of neuromuscular disease. There are other types of neuromuscular disorder. SMA is a disorder of motor neuron of brainstem or anterior horn cells of the spinal cord. Weakness and increased fatiguability are important features of the neuromuscular disease. Limb weakness first appears in the legs before arms. There is also marked delay in motor development. It’s also known as the Continue Reading…..