The neurological examination of the pediatric patient must be couched in the context of neurodevelopmental milestones. The normal neurological findings one would expect for a newborn are certainly different than a 2, 6 or 12-month-old infant. Obtaining developmental milestones is an important reflection of the maturation of the child’s nervous system and assessing development is an essential part of the pediatric neurological examination. Delay in obtaining developmental milestones and abnormal patterns of development are important indicators of underlying neurological disease.
In assessing the child’s developmental level, the examiner must know the age when key social, motor, and language skills are normally acquired. There are several screening tools that can be useful for this such as the Denver Developmental Screening Test II.
There are several key principles of neurodevelopment to keep in mind. First, the development of motor control proceeds in a head to toe fashion. The baby first develops head control, then trunk control (sitting), and finally controls the lower extremities (walking). Second, primitive reflexes (such as the Moro, grasp, and Galant) are normally present in the term infant and diminish over the next 4 to 6 months of life. The postural reflexes (such as the positive support reflex, Landau, lateral propping and parachute) emerge at 3 to 8 months of age. Persistence of primitive reflexes and the lack of development of the postural reflexes are the hallmark of an upper motor neuron abnormality in the infant.
Another very important part of assessing brain development is measuring the growth of the brain. This is accomplished by measuring the head circumference, which is an accurate reflection of brain size. The brain grows to 80% of its adult volume during the first 2 years of life so many neurological diseases that occur early in life will impact the growth of the brain. A small head (microcephaly) or a large head (macrocephaly or hydrocephalus) can be key findings in explaining the neurological abnormalities of a child. It is essential to plot head circumference on a standardized head growth chart such as the Nellhaus chart.
First: Stop, Look, and Listen
Because the infant and child are unable to fully cooperate for the standard neurological examination, the examination must be tailored to the child and their developmental level and temperament. The first part of the examination is to stop, look, and listen. You will learn more about the child’s neurologic status by initial hands-off careful observation than you will by forcing the child to conform to your pattern of performing the neurological examination. By watching the baby’s spontaneous activity, you can determine a great deal about their mental status, cranial nerve, coordination and motor status.
Second: Make it a Game
The second part of the examination is the hands-on part, which extends and further clarifies your initial observations. For this part of the examination, make it into a game that engages the child’s curiosity and imagination. The exam is less threatening and the child much more cooperative when toys are used and the examination tools are turned into inviting play objects. For example the use of finger puppets for coordination testing and turning the reflex hammer into an imaginary horse when testing deep tendon reflexes.
Third: Save the Worst for Last
The third and last part of the examination are all those things that are the most threatening and unsettling for the child such as undressing the child for a complete examination, looking at the fundus with an ophthalmoscope, using the otoscope, testing the gag reflex or measuring the head circumference.
General Physical Examination
In the neurological assessment of the child don’t neglect the general physical examination. Some of the parts of the general examination that are particularly important to note are the following:
Somatic growth - measure height and weight and compare percentiles with head circumference.
Search for dysmorphic features - carefully study the face especially the midface. There is the old adage that the face reflects the brain because anomalies of the midface are often associated with underlying brain malformations.
Eye examination - children are often uncooperative and it is hard to get a good look at the fundus but patience and perseverance pays off. The retina is said to be the window to the brain and the retinal examination can give valuable information for the neurological assessment.
Skin search - a careful complete skin search is important. Look for the stigmata of the neurocutaneous syndromes such as café au lait or ash leaf lesions.
Abdomen - palpate for visceromegaly, which can indicate the presence of one of the storage diseases.
Spine - look for scoliosis and any sacral anomalies.