Muscular Hypotonia: Definition, Causes, Symptoms, Diagnosis and Treatment

It is a condition where the muscle tone of an individual is reduced.

This decrease in muscle tone is generally found in children. When a child is born with low muscle tone or hypotonia, it is called benign congenital hypotonia.

Low muscle tone or hypotonia is usually detected in early childhood in children and is usually a symptom of a medical condition in adults.

When low muscle tone or hypotonia occurs in adults, it is usually associated with an underlying disease.

It can occur as a result of certain medical conditions, such as cerebral palsy or muscular dystrophy, which is a progressive neuromuscular disorder.

Children born with muscular hypotonia will be slow to achieve normal milestones, will be malleable when held, will also have a delay in keeping their head up, will not be able to sit for long, will have frequent jaw dislocations, neck and hips.

They may also have a slow chewing response and have difficulty feeding as a result of this condition.

Causes of muscle hypotonia

Low muscle tone or hypotonia can be caused as a result of a variety of medical conditions. Sometimes the causes of muscle hypotonia can also be genetic.

Generally, central nervous system disorders and progressive neuromuscular disorders are the main cause of low muscle tone or hypotonia.

Some of the medical conditions that can cause muscle hypotonia are:

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

Symptoms

In addition to low muscle tone, there are certain other symptoms that are associated with muscle hypotonia.

These symptoms are variable and depend on the cause of the disease.

Some of the symptoms associated with muscle hypotonia are:

  • An extremely smooth muscle sensation.
  • Difficulty extending the limb beyond normal.
  • In children with low muscle tone or hypotonia, there will be symptoms of delayed achievement of gross motor skills and problems with eating.
  • Shallow breathing is another symptom seen in children with this condition.
  • Children with low muscle tone or hypotonia also have symptoms of an inactive gag reflex.

Diagnosis of muscle hypotonia

Depending on the symptoms that the patient shows if low muscle tone or hypotonia is suspected, either in a child or in an adult, the following tests will be performed to confirm the diagnosis to find the cause of it.

Radiographic studies in the form of an MRI of the affected muscles can be done to see if there are any abnormalities within the muscle that may be causing low muscle tone.

A spinal cord MRI may also be done to look for any abnormalities in the spinal cord and nerves that cause low muscle tone or hypotonia.

Blood tests can be done to rule out any infection that may be responsible for causing this condition.

Electromyography is done in the extremities to look for any abnormalities in muscle function.

A lumbar puncture may also be performed to look for any abnormalities and rule out other medical conditions that may be causing low muscle tone or hypotonia.

A muscle biopsy may be done in which a sample of muscle tissue is taken from a weak muscle and sent for analysis.

This will give the doctor an idea of ​​any abnormalities within the muscle itself that may be causing low muscle tone or hypotonia.

Treatment of muscle hypotonia

Treating a patient with low muscle tone or hypotonia is challenging and involves a multi-specialty approach depending on the cause and extent of the condition.

Treatment for low muscle tone or hypotonia depends on the age and general health of the patient.

It also depends on how far the disease has progressed.

Certain medications can also be used depending on the cause of low muscle tone or hypotonia.

In case it is caused by an infection such as meningitis or encephalitis, antibiotics may be prescribed to treat the infection first, followed by intense physical therapy to strengthen the muscles and increase muscle tone.

In case the low muscle tone or hypotonia is due to a neuromuscular disorder such as muscular dystrophy or myasthenia gravis, it can be treated with medications such as physostigmine.

Steroids can also be used to increase the muscle tone of the patient.

In congenitally low muscle tone or hypotonia, no treatment is recommended except aggressive exercise to increase muscle tone and strength.

Joint dislocations that are very common in children with low muscle tone or hypotonia may require treatment.

Once the cause of the patient’s low muscle tone or hypotonia is established, the doctor formulates a treatment plan that usually includes aggressive physical therapy along with gross and fine motor skills training to make the patient more independent.

Treatment will include consultations directly from a pediatrician to a neurologist, physical therapist, occupational therapist to a psychologist.

As some children grow up they may find themselves lagging behind their peers in terms of gross and fine motor skills due to low muscle tone or hypotonia.

Exercises play an important role in treating low muscle tone or hypotonia.

The goal of exercise is to increase blood flow to the affected area so that the muscle becomes stronger and muscle tone increases.

The aim of the exercises is also to increase the fine and gross motor skills of the patient.

Some of the exercises that are recommended in cases of low muscle tone or hypotonia are:

Massage and compression

This is an extremely important exercise for patients with low muscle tone or hypotonia.

A massage in the affected area increases the blood flow to this area and stimulates the development of the muscles.

This massage should be done judiciously every day until there is a significant improvement in the strength and tone of the patient suffering from low muscle tone or hypotonia.

In some cases, compresses that need to be worn for a few hours every day can also be used to increase blood flow to the affected area, leading to further development of muscle tissue and helping to treat low muscle tone or hypotonia.

Weight training exercises

Certain simple weight training exercises at home can also be done to increase tone in patients suffering from low muscle tone or hypotonia.

This can be done especially for children by using bean bags that the child is asked to pick up.

Gradually, as strength increases, more weight can be added with objects such as books or other heavy items.

This exercise can help improve muscle tone and strength in a patient suffering from low muscle tone or hypotonia.

Muscle stimulation exercises

Muscle areas that are identified as underdeveloped or have low muscle tone or hypotonia can be stimulated by pressure massage and using heat and cold.

Muscle stimulation exercise can be used in children and adults with low muscle tone or hypotonia.

These exercises increase blood flow to the affected muscle, therefore not only strengthening the muscle but also improving muscle tone.

Fine motor skills development exercises

This is also an important aspect of muscle tone development in patients with low muscle tone or hypotonia.

They are simple exercises, especially for children with low muscle tone or hypotonia, where the child is asked to pick up an item placed at a distance on a table.

The effort made by the child to pick up the object increases the strength of the affected muscle and helps improve the child’s fine motor skills.

To improve coordination, the child may be asked to rub the left hand and foot together and then the right hand and foot.

This not only helps in muscle coordination but also helps improve muscle tone and strength in patients with low muscle tone or hypotonia.