Hypotonia, or poor muscle tone, is usually detected at birth or during infancy. If your infant has hypotonia, he or she may appear limp at birth and not be able to keep his or her knees and elbows slightly bent. Your child may continue to struggle with feeding and motor skills.
Many different diseases and disorders cause the symptoms of hypotonia. It is easily recognizable because it affects muscle strength, motor nerves, and the brain. However, diagnosing the disease or disorder that is causing the problem can be challenging.
Hypotonia is sometimes called floppy muscle syndrome.
Depending on the underlying cause, hypotonia can appear at any age. Signs of hypotonia in infants and children are:
- poor or no head control
- delay in gross motor skills development such as crawling
- delay in fine motor skills development such as grasping a crayon
Signs of hypotonia at any age are:
- decrease in muscle tone
- decrease in strength
- poor reflexes
- speech difficulties
- decrease in activity endurance
- weakened posture
Hypotonia can be triggered by a problem with the nervous system or muscular system. Sometimes it is the result of injury, illness, or an inherited disorder. Some causes may not be identified.
Some children are born with hypotonia that is not related to a separate condition. This is called benign congenital hypotonia. Physical, occupational, and speech therapy can help your child gain muscle tone and stay on track with development. Some children with benign congenital hypotonia have minor developmental delays or learning disabilities that continue through childhood.
Hypotonia can be caused by underlying conditions that affect the brain, central nervous system, or muscles. These include:
- cerebral palsy
- brain damage (often due to lack of oxygen at birth)
- muscular dystrophy
In many cases, these chronic conditions require lifelong care and treatment.
Hypotonia may also be caused by genetic conditions. Some of these conditions include:
- Down syndrome
- Prader-Willi syndrome
- Tay-Sachs disease
- Trisomy 13
Children with Down syndrome and Prader-Willi syndrome often benefit from therapy. Children with Tay-Sachs disease and Trisomy 13 typically have shortened lives.
Rarely, hypotonia is caused by botulism infections or contact with poisons or toxins. However, it often goes away after you recover.
Hypotonia may be diagnosed at birth. You may not notice your child’s condition until he or she is older. An indicator is that your child is not meeting developmental milestones. Schedule regular appointments for your child with a doctor and mention concerns you have about your child’s progress.
Your doctor will assess your child’s development and run tests if he or she has concerns. Tests may include blood tests, and MRI and CT scan imaging.
If you notice sudden signs of the condition in a person of any age, seek emergency medical care as soon as possible.
Treatment varies depending upon how your child is affected. Your child’s general health and ability to participate in therapies will help shape a treatment plan. Some children work frequently with physical therapists. Depending upon your child’s abilities, he or she may work toward specific goals such as sitting upright, walking, or taking part in sports. In some cases, your child may need help with his or her coordination and other fine motor skills.
Children with severe conditions may need wheelchairs for mobility. Hypotonia can cause complications such as frequent joint dislocations and a need for casts or braces to correct and prevent injuries.
The long-term outlook depends upon the following:
- underlying cause
- muscles affected
Having hypotonia can be challenging. It is often a lifelong condition, and you will need to learn coping mechanisms and may need therapy. However, it is not life threatening, except in the cases of motor neuron or cerebellar dysfunction.