Hypotonic Cerebral Palsy

Hypotonic Cerebral Palsy in Children

The word “hypotonic” translates to low muscle tone. Statistics show that hypotonic cerebral palsy accounts for under 50% of cerebral palsy sufferers, and is generally associated with non-spastic cerebral palsy. To understand hypotonic cerebral palsy (sometimes referred to as atonic CP), it is helpful to have knowledge about the disorder as a whole.

Cerebral palsy is a group of disorders that sometimes affects a person’s intellectual ability as well as the victim’s ability to move and to maintain balance and posture.

Statistics show half a million Americans are affected by cerebral palsy. By definition, hypotonic cerebral palsy refers to the brain’s functioning (cerebral), to any disorder involving impairment in control of bodily movement (palsy) and low muscle tone (hypotonic).

Symptoms of Hypotonia

Those with hypotonic cerebral palsy might seem “floppy” or unsteady when they walk. Hypotonic cerebral palsy sufferers often have difficulty in maintaining posture while sitting or standing. The effects of this condition are more pronounced in some patients than in others, however, hypotonic cerebral palsy does not get worse over time (muscle tone actually increases with age, but it never reaches normal levels).

The most common symptoms of hypotonia are problems with mobility and posture, breathing and speech problems, ligament and joint problems, and poor reflexes.

Those children who are hypotonic will typically have problems with flexing the elbows and knees, which will cause them to hang loosely at their sides. They may also have poor head control, twitching in the tongue, difficulty swallowing, and affected limbs of the patient may experience muscle pain and cramps.

Hypotonia is most often diagnosed during infancy (before the age of three) and may also be known as “floppy infant syndrome” or “infantile hypotonia.”

Causes of Hypotonic Cerebral Palsy

• Acquired Hypotonic Cerebral Palsy – This type of cerebral palsy occurs when there is damage to the brain after the time of birth. This damage often occurs during the first months or years of life. Brain injury, bacterial meningitis, viral encephalitis, or head injuries are some of the most-common causes of acquired cerebral palsy.
• Congenital Hypotonic Cerebral Palsy – This type of cerebral palsy occurs when there is an incident which takes place before, during, or shortly after birth which damages the motor centers of the brain. Most common causes of congenital cerebral palsy include:
  • Lack of Oxygen to the Brain – If the brain is denied oxygen for an extended period of time during labor or delivery, it may be permanently damaged and result in hypotonic cerebral palsy. Lack of oxygen (hypoxia) accounts for ~60% of cerebral palsy diagnoses.
  • Infections during Pregnancy – A mother can pass infections (such as rubella) to the child during pregnancy, which can damage the developing nervous system resulting in hypotonic cerebral palsy. Other infections like cytomeqalovirus and toxoplasmosis can also cause infections which may lead to hypotonic cerebral palsy.
  • Jaundice or kernicterus – Jaundice is a condition in which excessive amounts of bilirubin dissolve the layer of fat which is normally under the skin causing skin to appear yellow. Severe jaundice can damage the brain and can ultimately result in hypotonic cerebral palsy if not properly treated in time.
  • Other Causes – Other more general, possible causes of hypotonic cerebral palsy include: breech birth, complicated delivery or labor, low birth weight, nervous system defects, maternal bleeding, maternal hyperthyroidism, and doctor error.

Doctors diagnose hypotonic cerebral palsy by testing motor skills and reflexes, looking into medical history, and employing a variety of specialized tests.

Although its symptoms may change over time, hypotonic cerebral palsy by definition is not progressive, so if a patient shows increased impairment, the problem may be something other than hypotonic cerebral palsy.