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FLOPPY CHILD
Hassan Mohammad Al-Shehri
Objectives
Definition Risk factors Classification History taking and signs of hypotonia Investigations Management and prognosis.
Introduction
Neurological disorders are common in Saudi Arabia.
accounts for 25–30% of all consultations to pediatrics
Definition
Muscle tone is defined as resistance to passive
movement.
Hypotonia means "low tone," and refers to a physiological state in which a muscle has decreased tone, or tension.
AssessmentPrenatal risk factors:• History of drug or teratogen exposure• Presence of polyhydramnios• Maternal diseases (diabetes, epilepsy)• Parental age• Consanguinity• Family history of neuromuscular disease• Other affected siblings
AssessmentBirth/perinatal risk factors (1) History of prematurity: increased risk for cerebral palsy or
central causes. (3) Difficulties sucking/swallowing: may be seen with hypoxic
ischemic injury but if not in context with overall clinical picture, reflects possible neuromuscular cause.
(4) Poor respiratory effort: may be seen with hypoxic ischemic injury but if not in context with overall clinical picture, reflects possible neuromuscular cause.
(5) Encephalopathy: if out of context of birth history, may reflect underlying metabolic disorder or severe cerebral dysgenesis.
(6) Neonatal seizures: may reflect underlying metabolic disorder or cerebral dysgenesis.
(7) Unexplained metabolic “lab” abnormalities: consider metabolic disturbances and inborn errors of metabolism.
Classification Central Spinal Cord Anterior Horn Cell Neuromuscular Junction Muscle Peripheral Nerves Metabolic myopathies
Classification Central Causes
Cerebral palsy Intracranial hemorrhage Cerebral malformations Chromosomal abnormalities Hypoxic ischemic encephalopathy Congenital infection Acquired infections Peroxisomal disorders Drug effects
Classification Spinal cord
Birth trauma (especially Breech delivery) Syringomyelia
Clues to diagnosis History of: - brain insult - seizures - dysmorphic features - lack of interest in surroundings - abnormal head size - spontaneous movements - normal or increased reflexes,
persistence of primitive reflexes
Classification Anterior Horn Cell
Spinal Muscular Atrophy Traumatic myelopathy
Classification Neuromuscular junction
Congenital myasthenia gravis Transient acquired neonatal myasthenia Infantile botulism
Classification Muscle
Muscular dystrophies (congenital myotonic dystrophy)
Congenital myopathies (e.g. central core disease)
Classification
Peripheral nerves
Hereditary sensory motor neuropathies Charcot-Marie-Tooth disease
Classification Metabolic myopathies
Acid maltase deficiency Carnitine deficiency Cytochrome-c-oxidase deficiency
Clues to diagnosis
Decreased fetal movements Alertness and responsiveness Weakness with little spontaneous
movements Absent or decreased reflexes Fasciculation, muscle atrophy Sensory loss.
History TakingAny significant family history?Was the hypotonia present at birth?Pregnancy and delivery history
Drug or teratogen exposure Decreased fetal movements Abnormal presentation Polyhydramnios/ oligohydramnios
Apgar scores Resuscitation requirements Cord gases
Signs of Hypotonia
In supine, Frog position Their heads lag when are held up They slip through at the shoulders Do not stand upright on their legs Form inverted U shape in ventral suspention Lie flat when in prone position.
Signs of Hypotonia
Poor ability to cough and clear airway secretions. Poor swallowing ability Crying character [weak, low pitched] Paradoxical breathing pattern. Intercostal muscles
paralyzed with intact diaphragm.
Signs of HypotoniaVentral suspensionInverted U position The back hangs over the
examiner's hand, and the limbs and head hang loosely
Passive extension of the legs
Pull to sit Head lag
Signs of Hypotonia
The same infant in horizontalsuspension. Note the inverted U posture.
Signs of Hypotonia
A 12-week-old male infant with excessive head-lag evident on ‘pull-to-sit’. Note the hypotonic posture of the legs with external rotation.
Signs of Hypotonia
Vertical suspension: The legs will be extended Decreased tone of the shoulder girdle allows the infant to slip
through the examiner's hands
Signs of Hypotonia
Ptosis and external ophthalmoplegia in a floppy weak child. Suggestive of myasthenia gravis.
Investigations
Required investigations depend upon history and physical examination findings.
Investigations Central Causes
Neuroimaging Ultrasound scan in the first instance MRI for structural abnormality EEG: if seizures suspected
Investigations Central Causes
Genetics review if any dysmorphic features present Karyotype (if dysmorphic features) TORCH screen DNA methylation studies or FISH for Prader-Willi syndrome
(if clinically indicated after a genetics review) Metabolic work up
Investigations Peripheral causes
Neurology services review Molecular genetics – CTG repeats, deletions in SMN gene Creatine kinase: If elevated in an early sample, repeat after
a few days. Nerve conduction studies Muscle biopsy
Depending on clinical situation, may be delayed until around 6 months of age as neonatal results are difficult to interpret
Management
Supportive[respiratory, gastrointestinal] Once the correct diagnosis is confirmed, specific
treatments should be offered if available Physiotherapy:
mainly preventative to avoid contractures and wasting, but will not increase muscle tone
Genetics counseling.
Prognosis
Currently no known treatment or cure for most 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.
Prognosis
In some cases, muscle tone improves over time, or the patient may learn mechanisms that enable him to overcome the most disabling aspects of the disorder.
Hypotonia caused by cerebellar dysfunction or motor neuron diseases can be progressive and life-threatening.
Resources
Mohammed M.S. Jan (2007) , “The hypotonic infant: Clinical approach”. Journal of Pediatric Neurology 5 2007
Nelson Essential of Pediatrics 5th edition Pedbase.org
Thank You!