2. The word floppy in the terminology floppy infant
refers to:-
1. Reduction in the tone of muscles
2. Laxity of ligaments and joints
3. And occasionally to reduction in power of muscles
To be precise the term should be restricted to hypotonia alone.
3. Floppy Infant Presenting Features
• Hypotonia –
Abnormal Postures
Diminished Resistance to passive movements
Abnormal Range of Joint Movements
• Delay in Motor Milestones
4. • Clinical signs in a floppy infant
1. The frog leg posture
2. Slipping through the fingers on vertical suspension
3. Rag doll appearance on ventral suspension
4. The traction response showing head lag and excessively rounded back
5. Associations: Flat occiput, hair loss from occipital region, arthrogryposis,
congenital dislocation of the hips and inguinal hernia
5.
6. • The floppy infants have a similar appearance with rare spontaneous
movement of the limbs.
• Chest wall deformities - long standing weakness of the chest wall
muscles.
• The supine infant assumes a frog leg posture, with the legs fully
abducted at the hips, the lateral surface of the thighs resting on the
bed and the arms lying extended at the sides of the body, flexed at
the elbows and hands beside the head.
7. Movements
• The muscles appear flabby.
• Diminished resistance to passive movement of the limbs
• Range of movement of the peripheral joints is increased.
8. • Poor muscle tone there may be inguinal hernia or visceroptosis.
• Hip dislocation may be seen even in the newborn.
• Due to in utero hypotonia one or more joints may show contractures
or the baby may be born with arthrogryposis multiplex congenita
9. Assessment of tone
• For a term newborn the resting posture is flexion of the extremities
with the extremities closely adducted to the trunk.
• After the first few days of life, the extremities are still predominantly
in the flexed position but they are not as tightly adducted as they are
in the first 48 hours of life.
10. Upper Extremity Tone
• Motor function of the upper extremities begins with passive range of
motion.
• Done by moving each extremity at the shoulder, elbow and wrist and
feeling the resistance and the range of movement.
• Too little resistance reflects hypotonia
11. Arm Traction
• Arm traction is done with the baby in the supine position.
• The wrist is grasped and the arm is pulled until the shoulder is slightly
off the mat.
• There should be some flexion maintained at the elbow.
• Full extension at the elbow is seen in hypotonia.
12. Arm Recoil
• Arm recoil tests tone and power of the biceps.
• The arms are held in flexion against the chest for a few seconds, then
are quickly extended and released. The arms should spring back to
the flexed position.
• The hypotonic infant will have slow incomplete recoil
13. Scarf Sign
• The baby’s hand is pulled to the opposite shoulder like a scarf.
• The hand should not go past the shoulder and the elbow should not
cross the midline of the chest.
• This happens in the hypotonic infant.
14. Fisting
• A newborn baby’s hand is held in a fisted position with the fingers flexed over the
thumb.
• The hand opens intermittently and will not always be held in a tight fisted
position.
• Rubbing the ulnar aspect of the hand or touching the dorsum of the hand will
often cause extension of the fingers.
• Over the first 1 to 2 months of life, the baby’s hand becomes more open.
• Persistence of a fisted hand is a sign of an upper motor neuron lesion in an infant.
15. Leg Traction
• The leg held at the ankle is pulled
upward until the buttock starts to be
lifted off the mat.
• The knee should maintain a flexed angle.
• Full extension of the knee with little
resistance to pulling on the leg is a sign
of hypotonia.
16. Leg Recoil
• The legs are fully flexed on the abdomen for a few seconds, then are
quickly extended and released.
• The legs should spring back to the flexed position.
• Legs that remain extended could be due to either hypotonia or
abnormal extensor tone.
17. Popliteal Angle
• The popliteal angle is an assessment of the tone of the hamstring muscles.
• It is done one leg at a time.
• The thigh is flexed on the abdomen with one hand and then the other hand
straightens the leg by pushing on the back of the ankle until there is firm
resistance to the movement.
• The angle between the thigh and the leg is typically about 90 degrees.
• Extension of the leg beyond 90 to 120 degrees would be seen in hypotonia
18.
19. Heel to Ear
• Holding the baby’s foot in one hand, draw the leg towards the ear to
see how much resistance there is to the maneuver.
• The foot should go to about the level of the chest or shoulder, but not
all the way to the ear.
• If the foot can be drawn to the ear then there is hypotonia.
20. Neck Tone
• Passively rotate the head towards the shoulder.
• The chin should be able to rotate to the shoulder but not beyond the
shoulder.
• If the chin goes beyond the shoulder then there is hypotonia of the
neck muscles
21. Pull to sit:
• When pulled up from the supine to the sitting position, the head of
the baby lags.
23. • Look for evidence of hypothyroidism, malnutrition or rickets.
• The first aim is to distinguish a central versus a peripheral pathology.
24. Clues for central nervous system pathology
1. History of global developmental delay, seizures, movement disorder or speech
delay.
2. Persistent fisting
3. Early use of one hand only
4. Dysmorphic features
5. Involvement of other organs like hepato-splenomegaly
6. Psuedobulbar paralysis, exaggerated deep tendon reflexes or clonus
25. Clues for peripheral nervous system pathology
1. Paucity of limb movement particularly antigravity movements
2. Absent or depressed tendon reflexes
3. Muscle hypertrophy or atrophy
4. Fasciculations
5. Typical facial features peculiar to some myopathies
6. History of consanguinity or family history that is suggestive
7. Myotonia or myotonia in the mother
8. Selective motor delay without cognitive involvement
26. Central disorders that could result in a floppy
infant
Cerebral causes
• a. Hypotonic Cerebral palsy
• b. Chromosomal disorders including Down’s syndrome and Prader Willi
• c. Genetic disorders like familial dysautonomia and Lowe’s syndrome
• d. Peroxisomal disorders like Zellweger’s
• e. Endocrine like hypothyroidism
• f. Metabolic disorders like rickets and renal tubular acidosis
• g. Cerebral malformations
• h. Inborn errors of metabolism like GM1 gangliosidosis
Spinal causes
• a. Hypoxic injury to the spinal cord
• b. Traction injury to the spinal cord
27. Causes of a peripheral pathology in a floppy infant
Anterior horn cell diseases
a. Spinal muscular atrophy (SMA)
b. Congenital poliomyelitis
Radiculopathies
a. Chronic inflammatory demyelinating polyneuropathy
b. AIDP when the onset was in utero
28. Neuropathies
a. HMSN
b. HSAN
c. Congenital hypomyelinating neuropathy
Neuromuscular junction pathology
a. Botulism
b. Transient neonatal myasthenia
c. The congenital myasthenic syndromes. Autoimmune myasthenia
Muscle diseases
29. The muscle diseases:-
a. The congenital myasthenias
b. Congenital muscular dystrophy
c. The myotonic muscle diseases
d. The inflammatory myopathies
e. The metabolic myopathies
f. The mitochondrial muscle disorders
30. • Hypotonia with Weakness –
1. Neuromuscular Disorders
Hypotonia without Weakness –
1. CNS
2. Metabolic
3. Chromosomal
31. Differentiating Features of a Floppy Infant
according to Site of Involvement
Site of involvement
Extent of weakness
Proximal vs.
distal weakness
Face Arms Legs
Central - + + > or =
Anterior horn cell + ++++ ++++ > or =
Peripheral nerve - +++ +++ <
Neuromuscular
junction
+++ +++ +++ =
Muscle Variable ++ + >
32. Differentiating Features of a Floppy Infant
according to Site of Involvement (Contd.)
Site of
involvement
Deep tendon
reflexes EMG Muscle biopsy
Central Normal or
increased
Normal Normal
Anterior horn cell Absent Fasciculation /
fibrillation
Denervation
pattern
Peripheral nerve Decreased Fibrillation Denervation
pattern
Neuromuscular
junction
Normal Decremental /
incremental
Normal
Muscle Decreased Short duration small
amplitude potential
Characteristic
33. When a peripheral disease is suspected
• A creatine kinase (CK) level in serum is the first investigation to be done.
• Depending on the CK value and the clinical profile electrophysiological studies are planned.
• Nerve conduction studies show abnormal distal latency and conduction velocities in the
neuropathies.
• Sensory conduction studies alone may help in the diagnosis of the Hereditary Sensory
Autonomic Neuropathies.
• Inflammatory muscle diseases and anterior horn cell diseases on EMG study may show
spontaneous activity in the form of fasciculations and positive sharp waves.
• The myotonic muscle disorders on EMG studies show spontaneous activity in the form of
myotonia.
34. • Muscle diseases need detailed EMG studies but the electrophysiology
contributes little to the etiological diagnosis.
• Genetic studies are done in those cases where it is possible.
• When one suspects that the child has SMA, genetic studies are the
choice today if the patient can afford it.
• Genetic studies can also be done in the myasthenic syndromes and
congenital myotonic dystrophy
35. • Muscle biopsy and immunohistochemical staining helps to distinguish
the various muscle pathologies
• Selected cases like some of the congenital myopathies and some
cases of mitochondrial myopathies may benefit from electron
microscopic studies of the biopsy specimen.
• In the case of myasthenia single fiber EMG is needed for diagnosis.
36. When a central disorder is suspected
• A high index of suspicion is the key factor.
• The investigations cannot be stereotyped but tailored according to
the clinical findings.
• The patient may need brain imaging, a metabolic work up,
chromosomal analysis or specific metabolic studies
37. Therapeutic aspects
• All the infants will need rehabilitation.
• Excellent remedial measures would include thyroid replacement in
the hypothyroid, rehabilitation of the malnourished floppy infant,
treatment of rickets
• Surgery for cataract and glaucoma in Lowe’s disease
• Treatment of myotonia in myotonia congenital and congenital
myotonic dystrophy
38. • Physiotherapy, occupational therapy, special education in the
mentally challenged and surgical correction for deformities are
offered in cases that need them.
39. Prevention
• Prevention of these disease states is of paramount importance as the treatment
has limitations.
• Health education to prevent consanguinous parentage is a key point.
• The exact etiological diagnosis especially with a genetic corroboration will help to
inform the family regarding the chances of a next offspring being affected.
• In the next pregnancy prenatal diagnosis and the option of medical termination
of pregnancy can be discussed.
• Early detection of several of these disorders helps in treatment and disability
reduction.
40. Summary :-
• Spinal muscular atrophy - commonest cause of floppy children
followed by congenital muscle disease.
• 11% of the cases still remained unclassified despite sophisticated
investigative techniques.
• EMG was a good screening modality for floppy children.
42. Key Messages in Approach to a Floppy Child
• First ABC of resuscitation
• Try to find out cause but again simple clinical examination is the first
thing
• Any sedative drug given during labour
• Investigations
• Only those investigations which are necessary
• Sepsis
• Another sophisticated investigations
• Improve the quality of life probably quantity can not be improve in
most of the cases
