Reduced Muscle Tone
SMA type 1 babies have thinner and weaker muscles because there are fewer motor neurons in their bodies. As muscles weaken, the limbs become floppy and lurchy. The kids are less flexible, they can’t sit up without assistance, and their muscle weakness and wasting get worse over time. Muscle wasting can be accompanied by pain, numbness and swelling. Malnutrition can also cause muscle weakness as a result spinal muscular atrophy. Malnutrition also causes the muscles to lose mass and tone.
