Published: 18 Jun 2025

ICD9: 779.89      ICD10: P94.2      ICD11: VV6Y

Hypotonia, also known as "floppy baby syndrome" (although it affects people of all ages), refers to decreased muscle tone.
It's not a specific disease, but rather a symptom of an underlying problem.

Here's a breakdown of what that means:

Muscle Tone: Even when muscles are relaxed, they maintain a certain amount of tension, called muscle tone. This tone helps with posture, movement, and overall stability.

Hypotonia (Low Tone): In hypotonia, this underlying tension is reduced. Muscles feel soft and pliable, and there's less resistance to passive movement.

Characteristics of Hypotonia:

"Floppy" appearance: Limbs may hang limply, and the person may feel like a rag doll when held.
Decreased strength: While not always the case, hypotonia can often be associated with weakness.
Poor head control: Especially in infants, difficulty holding the head upright.
Difficulty feeding: Poor suck and swallow reflexes.
Delayed motor skills: Difficulty achieving developmental milestones like sitting, crawling, and walking.
Lethargy: The person may seem tired and have reduced activity.
Joint hypermobility: Joints may be more flexible than normal due to reduced muscle support.
Shallow breathing: In severe cases, it can affect respiratory muscles.

Causes of Hypotonia:

Hypotonia can be caused by a wide range of conditions affecting the brain, spinal cord, nerves, or muscles. Some common causes include:

Genetic disorders: Down syndrome, Prader-Willi syndrome, and others.
Brain injuries: Cerebral palsy, traumatic brain injury, or stroke.
Neuromuscular disorders: Muscular dystrophy, spinal muscular atrophy.
Metabolic disorders: Certain conditions that affect the body's metabolism.
Infections: Meningitis, encephalitis, or sepsis.
Prematurity: Premature babies often have low muscle tone due to incomplete development.
Cerebellar disorders: Conditions affecting the cerebellum, which controls coordination and balance.
Connective tissue disorders: such as Ehlers-Danlos Syndrome.

Diagnosis and Treatment:

Diagnosing the underlying cause of hypotonia is crucial. This usually involves:

Physical examination: Assessing muscle tone, reflexes, and motor skills.
Neurological examination: Evaluating nerve function.
Blood tests: To check for metabolic or genetic disorders.
Imaging studies: MRI or CT scans of the brain and spinal cord.
Electromyography (EMG): To assess muscle and nerve function.
Genetic testing: To identify specific genetic mutations.

Treatment depends on the underlying cause and may include:

Physical therapy: To improve muscle strength and coordination.
Occupational therapy: To help with daily living skills.
Speech therapy: To address feeding and communication problems.
Medications: To manage specific conditions.
Surgery: In some cases, to correct structural problems.
Supportive care: To address the individual's needs.

Important Note: Hypotonia is a complex symptom, and its severity and prognosis can vary widely depending on the underlying cause. It's crucial to consult a medical professional for diagnosis and treatment. Self-diagnosing or treating hypotonia is strongly discouraged.