Muscular strength

The muscles throughout the body of people with MSS have somewhat reduced strength. Doctors call this 'hypothonia'. Normal developments such as being able to hold your head upright independently as a baby and learning to crawl as a toddler are slower and take more strength. When playing, children fall easily. Learning to walk sometimes only works with aids.

Reduced muscle strength can also cause drooling. Other contributing factors are the short lower jaw, difficulty swallowing and less awareness of saliva flow.