Muscle weakness (hypotonia) Symptoms & Causes

What causes muscle weakness?

Hypotonia can be caused by a variety of conditions, including those that involve the central nervous system, muscle disorders and genetic disorders. Some common causes can include but are not limited to:

•   Down syndrome
•   Muscular dystrophy
•   Cerebral palsy
•   Prader-Willi syndrome
•   Myotonic dystrophy
•   Marfan syndrome 
•   Tay-Sachs disease

What are the symptoms of muscle weakness?

The following are common symptoms associated with hypotonia. Each child may experiences symptoms differently. Symptoms vary depending on the underlying cause of the problem.

•   Decreased muscle tone, muscles feel soft and doughy
•   Ability to extend limb beyond its normal limit
•   Failure to acquire motor related developmental milestones (such as holding head up without support from parent,
    rolling over, sitting up without support, walking)
•   Problems with feeding (inability to suck or chew for prolonged periods)
•   Shallow breathing
•   Mouth hangs open with tongue protruding (under-active gag reflex)

Some hypotonias are not progressive and are of an unknown origin, a condition known as benign congenital hypotonia.

•   Central nervous system function and intelligence in children is normal.
•   Children with benign congenital hypotonia may not experience developmental delay.
•   Some children acquire gross motor skills (sitting, walking, running, jumping) more slowly than most.

The signs and symptoms of hypotonia resemble that of other conditions. Always consult a physician for a diagnosis.