Hypotonia is a condition of abnormally low muscle tone (the amount of tension or resistance to movement in a muscle), often involving reduced muscle strength. Hypotonia is not a specific medical disorder, but a potential manifestation of many different diseases and disorders that affect motor nerve control by the brain or muscle strength. Recognizing hypotonia, even in early infancy, is usually relatively straightforward, but diagnosing the underlying cause can be difficult and often unsuccessful. The long-term effects of hypotonia on a child's development and later life depend primarily on the severity of the muscle weakness and the nature of the cause. Some disorders have a specific treatment but the principal treatment for most hypotonia of idiopathic or neurologic cause is physical therapy to help the person compensate for the neuromuscular disability. The International Statistical Classification of Diseases and Related Health Problems (most commonly known by the abbreviation ICD) provides codes to classify diseases and a wide variety of signs, symptoms, abnormal findings, complaints, social circumstances and external causes of injury or disease. ... The International Statistical Classification of Diseases and Related Health Problems 10th Revision (ICD-10) is a coding of diseases and signs, symptoms, abnormal findings, complaints, social circumstances and external causes of injury or diseases, as classified by the World Health Organization (WHO). ... // P00-P96 - Certain conditions originating in the perinatal period (P00-P04) Fetus and newborn affected by maternal factors and by complications of pregnancy, labour and delivery (P00) Fetus and newborn affected by maternal conditions that may be unrelated to present pregnancy (P01) Fetus and newborn affected by maternal complications of... The International Statistical Classification of Diseases and Related Health Problems (most commonly known by the abbreviation ICD) provides codes to classify diseases and a wide variety of signs, symptoms, abnormal findings, complaints, social circumstances and external causes of injury or disease. ... The following is a list of codes for International Statistical Classification of Diseases and Related Health Problems. ... The Disease Bold textDatabase is a free website that provides information about the relationships between medical conditions, symptoms, and medications. ... MedlinePlus (medlineplus. ... Medical Subject Headings (MeSH) is a huge controlled vocabulary (or metadata system) for the purpose of indexing journal articles and books in the life sciences. ... A top-down view of skeletal muscle Muscle (from Latin musculus little mouse [1]) is contractile tissue of the body and is derived from the mesodermal layer of embryonic germ cells. ... Motor nerves allow the brain to stimulate muscle contraction. ... In animals, the brain or encephalon (Greek for in the head), is the control center of the central nervous system, responsible for behaviour. ... A human infant The word Infant derives from the Latin in-fans, meaning unable to speak. ... In general, a diagnosis (plural diagnoses) has two distinct dictionary definitions. ...

Etiology of hypotonia

Some conditions known to cause hypotonia include:

Congenital - i.e. present from birth (including genetic disorders presenting within 6 months) A congenital disorder is a medical condition or defect that is present at or before birth (for example, congenital heart disease). ...

• Genetic disorders are the most common cause
  • Down's syndrome - most common
  • 3-Methylcrotonyl-CoA carboxylase deficiency ^[1]
  • Achondroplasia
  • Aicardi syndrome
  • Canavan disease
  • Centronuclear myopathy (including myotubular myopathy)
  • Familial dysautonomia (Riley-Day syndrome)
  • Infantile spinal muscular atrophy such as Werdnig-Hoffman disease
  • Krabbe disease
  • Leigh's disease
  • Marfan's syndrome
  • Menkes syndrome
  • Methylmalonic acidemia
  • Nonketotic Hyperglycinemia (NKH) or Glycine Encephalopathy (GCE)
  • Prader-Willi syndrome
  • Tay-Sachs disease
  • Trisomy 13
  • 22q13 deletion syndrome

• Developmental disability
  • Cerebellar ataxia (congenital)
  • Dysfunction in Sensory Integration (DSI)
  • Developmental Dyspraxia
  • Hypothyroidism (congenital)
  • Hypotonic Cerebral palsy
  • Teratogenesis from in utero exposure to Benzodiazepines

Acquired - i.e. onset occurs after birth A genetic disorder is a disease caused by abnormalities in genes or chromosomes. ... 3-methylcrotonyl-CoA carboxylase deficiency is an inherited disorder in which the body is unable to process certain proteins properly. ... Circus Busch, 1906 Achondroplasia is a type of autosomal dominant genetic disorder that is a common cause of dwarfism. ... Aicardi syndrome is a congenital disorder thought to result from an abnormality of the X chromosome and characterized by absence of the corpus callosum, retinal abnormalities, and seizures (often infantile spasms). ... Canavan disease is an inherited disorder that causes progressive damage to nerve cells in the brain. ... Centronuclear myopathies (CNM) are a group of congenital myopathies where cell nuclei are abnormally located in skeletal muscle cells. ... Familial dysautonomia, or FD, is a disorder of the autonomic nervous system which affects the development and survival of sensory, sympathetic and some parasympathetic neurons in the autonomic and sensory nervous system resulting in variable symptoms including: insensitivity to pain, inability to produce tears, poor growth, and labile blood pressure... Spinal Muscular Atrophy (SMA) is a term applied to a number of different disorders, all having in common a genetic cause and the manifestation of weakness due to loss of the motor neurons of the spinal cord and brainstem. ... Werdnig-Hoffman disease (or Infantile spinal muscular atrophy, type I) is an autosomal recessive muscular disease. ... Krabbe disease (also known as globoid cell leukodystrophy or galactosylceramide lipidosis) is a rare, often fatal degenerative disorder that affects the nervous system. ... Leighs Disease, a form of Leigh syndrome, is a rare neurometabolic disorder that affects the central nervous system. ... Marfan syndrome is a connective tissue disorder characterized by unusually long limbs. ... Menkes disease, also called the kinky hair disease or Menkes kinky hair syndrome, is a disease of abnormal copper metabolism. ... Methylmalonic acidemia (MMA) is an inborn error of intermediary metabolism that may present in the early neonatal period with progressive encephalopathy and death due to a secondary hyperammonemia. ... Prader-Willi syndrome is a genetic disorder, in which seven genes (or some subset thereof) on chromosome 15 are missing or unexpressed (chromosome 15q partial deletion) on the paternal chromosome. ... Tay-Sachs disease (abbreviated TSD, also known as GM2 gangliosidosis, Hexosaminidase A deficiency or Sphingolipidosis) is a genetic disorder, fatal in all forms. ... Patau syndrome, also known as Trisomy 13, is a chromosomal aberration, a disease in which a patient has an additional chromosome 13. ... The deletion of the tip of the chromosome 22 is related to autistic behaviour, moderate to severe developmental delay and mental retardation. ... Developmental disability is a term used to describe life-long disabilities attributable to mental and/or physical or combination of mental and physical impairments, manifested prior to age twenty-two. ... For other uses, see Ataxia (disambiguation). ... // Developmental Dyspraxia is one or all of a heterogeneous range of psychological development disorders affecting the initiation, organization and performance of action[1]. It entails the partial loss of the ability to coordinate and perform certain purposeful movements and gestures in the absence of motor or sensory impairments. ... This article or section does not cite its references or sources. ... This article or section is in need of attention from an expert on the subject. ... // Teratogenesis is a medical term from the Greek, literally meaning monster-birth, which derives from teratology, the study of the frequency, causation, and development of congenital malformations—misleadingly called birth defects. ... Benzodiazepine tablets The benzodiazepines are a class of drugs with hypnotic, anxiolytic, anticonvulsant, amnestic and muscle relaxant properties. ... An acquired disorder is a medical condition which develops post-fetally; in contrast with a congenital disorder, which is present at birth. ...

• Genetic
  • Muscular dystrophy (including Myotonic dystrophy) - most common
  • Metachromatic leukodystrophy

• Infections
  • Encephalitis
  • Guillian-Barre syndrome
  • Infant botulism
  • Meningitis
  • Poliomyelitis
  • Sepsis

• Autoimmunity disorders
  • Myasthenia gravis - most common
  • Abnormal vaccine reaction

• Metabolic disorders
  • Hypervitaminosis D
  • Kernicterus
  • Rickets

• Neurological
  • Traumatic brain injury, such as the damage that is caused by Shaken Baby Syndrome

• Miscellaneous
  • Central nervous system dysfunction, including Cerebellar lesions
  • Hypothyroidism

Muscular dystrophy refers to a group of genetic, hereditary muscle diseases that cause progressive muscle weakness. ... Myotonic dystrophy (DM) is a chronic, slowly progressing, highly variable inherited multisystemic disease that can manifest at any age from birth to old age. ... Metachromatic leukodystrophy (MLD) is the most common form of a family of genetic diseases known as the leukodystrophies, diseases which affect the growth and/or development of myelin, the fatty covering which acts as an insulator around nerve fibres throughout the central and peripherial nervous systems . ... An infection is the detrimental colonization of a host organism by a foreign species. ... Encephalitis is an acute inflammation of the brain, commonly caused by a viral infection. ... Guillain-Barré syndrome (GBS), is an acquired immune-mediated inflammatory disorder of the peripheral nervous system (i. ... Botulism (from Latin botulus, sausage) is a rare but serious paralytic illness caused by a nerve toxin, botulin, that is produced by the bacterium Clostridium botulinum. ... Meningitis is the inflammation of the protective membranes covering the central nervous system, known collectively as the meninges. ... This article is about the disease. ... Sepsis (in Greek Σήψις, putrefaction) is a serious medical condition, resulting from the immune response to a severe infection. ... Autoimmunity is the failure of an organism to recognize its own constituent parts (down to the sub-molecular levels) as self, which results in an immune response against its own cells and tissues. ... Myasthenia gravis (sometimes abbreviated MG; from the Greek myastheneia, lit. ... A metabolic disorder is a medical disorder which affects the production of energy within individual human (or animal) cells. ... While vitamins are important in maintaining health, excessive levels of vitamins can lead to vitamin poisoning (hypervitaminosis). ... Kernicterus is damage to the brain centers of infants caused by jaundice. ... Rickets is a softening of the bones in children potentially leading to fractures and deformity. ... Neurology is a branch of medicine dealing with disorders of the central and peripheral nervous systems. ... A diagram showing the CNS: 1. ... The cerebellum (Latin: little brain) is a region of the brain that plays an important role in the integration of sensory perception and motor output. ... This article or section does not cite its references or sources. ...

Signs and objective manifestations

Hypotonic patients may display a variety of objective manifestations that indicate decreased muscle tone. Motor skills delay is often observed, along with hypermobile or hyperflexible joints, drooling and speech difficulties, poor reflexes, decreased strength, decreased activity tolerance, rounded shoulder posture, with leaning onto supports, and poor attention and motivation. The extent and occurrence of specific objective manifestations depends upon the age of the patient, the severity of the hypotonia, the specific muscles affected, and sometimes the underlying cause. For instance, some hypotonics may experience constipation, while others have no bowel problems.

Since hypotonia is most often diagnosed during infancy, it is also known as "floppy infant syndrome" or "infantile hypotonia." Infants who suffer from hypotonia are often described as feeling and appearing as though they are "rag dolls" or a "sack of jello," easily slipping through one's hands. This image demonstrates the floppiness of a hypotonic infant. They are unable to maintain flexed ligaments, and are able to extend them beyond normal lengths. Often, the movement of the head is uncontrollable, not in the sense of spasmatic movement, but chronic ataxia. Hypotonic infants often have difficulty feeding, as their mouth muscles cannot maintain a proper suck-swallow pattern, or a good breastfeeding latch. A ligament is a short band of tough fibrous connective tissue composed mainly of long, stringy collagen fibres. ... “Human Head” redirects here. ... In medicine, a chronic disease is a disease that is long-lasting or recurrent. ... For other uses, see Ataxia (disambiguation). ... Breastfeeding an infant Symbol for breastfeeding (Matt Daigle, Mothering magazine contest winner 2006) Breastfeeding is the feeding of an infant or young child with milk from a womans breasts. ...

Developmental delay

Children with normal muscle tone are expected to achieve certain physical abilities within an average timeframe after birth. Most low-tone infants have delayed developmental milestones, but the length of delay can vary widely. Motor skills are particularly susceptible to the low-tone disability. They can be divided into two areas, gross motor skills, and fine motor skills, both of which are affected. Hypotonic infants are late in lifting their heads while lying on their stomachs, rolling over, lifting themselves into a sitting position, remaining seated without falling over, balancing, crawling, and walking. Fine motor skills delays occur in grasping a toy or finger, transferring a small object from hand to hand, pointing out objects, following movement with the eyes, and self feeding. A motor skill is a skill required for proper usage of skeletal muscles. ... Fine motor skills can be defined as small muscle movements which occur in the fingers, in coordination with the eyes. ...

Speech difficulties can result from hypotonia. Low-tone children learn to speak later than their peers, even if they appear to understand a large vocabulary, or can obey simple commands. Difficulties with muscles in the mouth and jaw can inhibit proper pronunciation, and discourage experimentation with word combination and sentence-forming. Since the hypotonic condition is actually an objective manifestation of some underlying disorder, it can be difficult to determine whether speech delays are a result of poor muscle tone, or some other neurological condition, such as mental retardation, that may be associated with the cause of hypotonia. Mental retardation is a term for a pattern of persistently slow learning of basic motor and language skills (milestones) during childhood, and a significantly below-normal global intellectual capacity as an adult. ...

Muscle tone vs. muscle strength

The low muscle tone associated with hypotonia must not be confused with low muscle strength. In body building, good muscle tone is equated with good physical condition, with taut muscles, and a lean appearance, whereas an out-of-shape, overweight individual with fleshy muscles is said to have "poor tone." Neurologically, however, muscle tone cannot be changed under voluntary control, regardless of exercise and diet. Bodybuilder Anders Graneheim (Sweden) Bodybuilding is the sport of developing muscle fibers through the combination of weight training, increased caloric intake, and rest. ... The term overweight is generally used to indicate that a human has more body fat than is considered useful for the optimal functioning of the body. ... Neurology is a branch of medicine dealing with disorders of the nervous system. ...

In an article by Diane E Gagnon, M.Ed., PT,^[2] she explains

"True muscle tone is the inherent ability of the muscle to respond to a stretch. For example, if you quickly straighten the flexed elbow of an unsuspecting child with normal tone, the biceps will quickly contract in response (automatic protection against possible injury). When the perceived danger has passed, which the brain figures out really quickly once the stimulus is removed, the muscle then relaxes, and returns to its normal resting state.

"...The child with low tone has muscles that are slow to initiate a muscle contraction, contract very slowly in response to a stimulus, and cannot maintain a contraction for as long as his 'normal' peers. Because these low-toned muscles do not fully contract before they again relax (muscle accommodates to the stimulus and so shuts down again), they remain loose and very stretchy, never realising their full potential of maintaining a muscle contraction over time. "

Bodybuilder showing highly developed muscle tone. ... This article is about stretching as a form of physical exercise. ... Look up Biceps in Wiktionary, the free dictionary. ... A top-down view of skeletal muscle A muscle contraction (also known as a muscle twitch or simply twitch) occurs when a muscle cell (called a muscle fiber) lengthens or shortens. ...

Diagnosis

"A diagnosis of hypotonia is sometimes considered a form of muscular dystrophy or cerebral palsy, depending on the symptoms and the doctor. If the cause of the hypotonia is thought to lie in the brain, then it might be classified as a cerebral palsy. If the cause seems to be in the muscles, it might be classified as a muscular dystrophy, even though most forms of hypotonia are not seriously dystrophic. If the cause is thought to be in the nerves, it could be classified as either or neither. In any case, hypotonia is rarely an actual muscular dystrophy or cerebral palsy, and is often not classified as either one, or anything at all for that matter."^[3]

Diagnosing a patient includes obtaining family medical history and a physical examination, and may include such additional tests as computerized tomography (CT) scans, magnetic resonance imaging (MRI) scans, electroencephalogram (EEG), blood tests, genetic testing (such as chromosome karyotyping and tests for specific gene abnormalities), spinal taps, electromyography muscle tests, or muscle and nerve biopsy. CAT apparatus in a hospital Computed axial tomography (CAT), computer-assisted tomography, computed tomography, CT, or body section roentgenography is the process of using digital processing to generate a three-dimensional image of the internals of an object from a large series of two-dimensional X-ray images taken around... Magnetic Resonance Image showing a median sagittal cross section through a human head. ... Electroencephalography is the neurophysiologic exploration of the electrical activity of the brain by the application of electrodes to the scalp. ... Blood tests are laboratory tests done on blood to gain an appreciation of disease states and the function of organs. ... Genetic testing allows the genetic diagnosis of vulnerabilities to inherited diseases, and can also be used to determine a persons ancestry. ... Karyogram of human male using Giemsa staining. ... A patient undergoes a lumbar puncture at the hands of a neurologist. ... Electromyography (EMG) is a medical technique for evaluating and recording physiologic properties of muscles at rest and while contracting. ... Brain biopsy A biopsy (in Greek: bios = life and opsy = look/appearance) is a medical test involving the removal of cells or tissues for examination. ...

Mild or benign hypotonia is often diagnosed by physical and occupational therapists through a series of exercises designed to assess developmental progress, or observation of physical interactions. Since a hypotonic child has difficulty deciphering his spatial location, he may have some recognizable coping mechanisms, such as locking the knees while attempting to walk. A common sign of low-tone infants is a tendency to observe the physical activity of those around them for a long time before attempting to imitate, due to frustration over early failures. Developmental delay can indicate hypotonia.

Other names for hypotonia

• Low Muscle Tone
• Benign Congenital Hypotonia
• Congenital Hypotonia
• Congenital Muscle Hypotonia
• Congenital Muscle Weakness
• Amyotonia Congenita
• Floppy Baby Syndrome
• Infantile Hypotonia

Prognosis and treatment

There is currently no known treatment or cure for most (or perhaps all) causes of hypotonia, and objective manifestations can be life long. The outcome in any particular case of hypotonia depends largely on the nature of the underlying disease. In some cases, muscle tone improves over time, or the patient may learn or devise coping mechanisms that enable him to overcome the most disabling aspects of the disorder. However, hypotonia caused by cerebellar dysfunction or motor neuron diseases can be progressive and life-threatening.

Along with normal pediatric care, specialists who may be involved in the care of a child with hypotonia include developmental pediatricians (specialize in child development), neurologists, neonatologists (specialize in the care of newborns), geneticists, occupational therapists, physical therapists, speech therapists, orthopedists, pathologists (conduct and interpret biochemical tests and tissue analysis), and specialized nursing care.

If the underlying cause is known, treatment is tailored to the specific disease, followed by symptomatic and supportive therapy for the hypotonia. In very severe cases, treatment may be primarily supportive, such as mechanical assistance with basic life functions like breathing and feeding, physical therapy to prevent muscle atrophy and maintain joint mobility, and measures to try and prevent opportunistic infections such as pneumonia. Treatments to improve neurological status might involve such things as medication for a seizure disorder, medicines or supplements to stabilize a metabolic disorder, or surgery to help relieve the pressure from hydrocephalus (increased fluid in the brain).

For most hypotonics, the National Institute of Health recommends "physical therapy [to] improve motor control and overall body strength. Occupational therapy to assist with fine motor skill development and hand control, and speech-language therapy can help breathing, speech, and swallowing difficulties. Therapy for infants and young children may also include sensory stimulation programs." Ankle/foot orthoses are sometimes used for weak ankle muscles. Toddlers and children with speech difficulties may benefit greatly by using sign language. The National Institutes of Health is an institution of the United States government which focuses on medical research. ... Two sign language Intepreters working as a team for a school. ...

Breastfeeding

Low-tone infants often have difficulty feeding, especially coordinating the suck-swallow reflex required for proper breastfeeding.^[4] Early diagnosis of hypotonic newborns can help mothers find the support and information they need to establish a successful breastfeeding relationship. Hypotonic babies may take longer to breastfeed because of the poor timing of sucking bursts and the need for long rests. If feeding is inefficient, they will also require greater feeding frequency. A baby with low muscle tone may suck better when the head and bottom are level, indicating pillow support in the lap. If the infant tends to arch his back, it may be helpful to swaddle the child loosely with arms drawn across the chest and legs drawn up toward the belly with a rounded spine during feedings. It may be necessary to support the infant's chin with one's hand if jaw, ear, and temple movement are not observed. If the baby tolerates touch to the mouth and face, the mother might gently rub the baby's lips and the outer surface of the gums to stimulate muscle sensitivity before beginning feeding. "If the tongue does not have the tone, strength, or range of motion to lift and press the breast against the palate (roof of the mouth), the baby might compensate by pressing more with his jaws. This excessive compression is painful for the mother. Getting a deeper latch, making sure the baby is not tongue-tied, and using an asymmetrical latch to increase the amount of tongue in contact with the breast can all be helpful to reduce compression." ^[5] Finally, if nursing is too frustrating and stressful for mother and child, breast milk can be expressed by use of a breast pump and fed through a bottle. Breastfeeding an infant Symbol for breastfeeding (Matt Daigle, Mothering magazine contest winner 2006) Breastfeeding is the feeding of an infant or young child with milk from a womans breasts. ... Manual breast pump A breast pump is a mechanical device (powered manually or by electricity) that extracts milk from the breasts of a woman who is lactating. ...

Positions which allow for better drainage of the breast through the help of gravity or manual expressing/massage while the baby is nursing may improve milk intake at the breast. Proper latch can be taught/encouraged by reinforcing appropriate mouth/tongue movements with massage of the breast to increase flow. Taking extra time with feeds is helpful. Many low-tone babies have a hard time with the coordination of sucking, swallowing and breathing and taking frequent short breaks may be helpful.

Exclusive feeding of breastmilk, especially for infants who have frequent bouts of gagging due to poor coordination, can be helpful in avoiding some of the sequelae of aspiration of formula. Breastmilk is less irritating to the lungs and less likely to cause infection if aspirated. When weighing the benefits vs. risks of formula supplementation to encourage weight gain, the possibility of aspiration should be considered. It may be better to have a little slower gain and avoid the risk of non-breastmilk fluids being aspirated.

See also

• Hypertonia

An increase in stiffness, tension, and spasticity of a muscle. ...

References

1. ^ http://www.savebabies.org/diseasedescriptions/3MCC.php
2. ^ Tone versus Strength, by Diane E Gagnon, M.Ed., PT. Retrieved on 2007-06-07.
3. ^ The Benign Congenital Hypotonia Site. Retrieved on 2007-06-07.
4. ^ Breastfeeding an infant with neurological problems (PDF)
5. ^ Tactile Defensiveness and Other Sensory Modulation Difficulties (with Breastfeeding) Catherine Watson Genna, BS, IBCLC, New York City, New York, USA, From: LEAVEN, Vol. 37 No. 3, June-July 2001, pp. 51-53]. Retrieved on 2007-06-07.

• Exercises and Stimulation Therapy for Hypotonia from Early Parent Intervention Project (ARC Texas)
• Early recognition and intervention is the key to recovery for Benign Congenital Hypotonia Shannon Munro Cohen, RNC, BSN, and Teresa Whitt, Ph.D.
• Martin K, Inman J, Kirschner A, Deming K, Gumbel R, Voelker L (2005). "Characteristics of hypotonia in children: a consensus opinion of pediatric occupational and physical therapists". Pediatric physical therapy : the official publication of the Section on Pediatrics of the American Physical Therapy Association 17 (4): 275-82. PMID 16357683. 
• Overview at National Organization of Rare Disorders
• hypotonia at NINDS
• Encyclopedia of Children's Health

Year 2007 (MMVII) is now the current year, a common year starting on Monday of the Gregorian calendar and the AD/CE era. ... June 7 is the 158th day of the year in the Gregorian calendar (159th in leap years), with 207 days remaining. ... Year 2007 (MMVII) is now the current year, a common year starting on Monday of the Gregorian calendar and the AD/CE era. ... June 7 is the 158th day of the year in the Gregorian calendar (159th in leap years), with 207 days remaining. ... Year 2007 (MMVII) is now the current year, a common year starting on Monday of the Gregorian calendar and the AD/CE era. ... June 7 is the 158th day of the year in the Gregorian calendar (159th in leap years), with 207 days remaining. ... National Institutes of Health Building 50 at NIH Clinical Center - Building 10 The National Institutes of Health (NIH) is an agency of the United States Department of Health and Human Services and is the primary agency of the United States government responsible for biomedical research. ... The National Institute of Neurological Disorders and Stroke is a part of the U.S. National Institutes of Health. ...

External links

Support organizations

• National Rehabilitation Information Center (NRIC)
• Muscular Dystrophy Association (MDA)
• American Coalition of Citizens with Disabilities (ACCD)
• National Multiple Sclerosis Society (NMSS)
• March of Dimes Birth Defects Foundation

Online message boards

• Hypotonia Hope
• Children With Hypotonia
• ParentsPlace Hypotonia Message Board