Babies with congenital muscular dystrophy often have hypotonia (low muscle tone or floppiness) and may have reduced movements. Other common signs are contractures (tightness) of the ankles, hips, knees and elbows. Rarely, contractures can be severe and affect several joints (known as arthrogryposis). Contractures occur because the baby has not had the muscle strength to move around freely in the womb. Some babies with congenital muscular dystrophy may also have respiratory problems owing to weakness of breathing muscles.
In some children who do not have contractures, the first problems are noted only after a few months because of difficulties in holding the head up, or delays in learning how to sit unaided, to stand or walk.