A large part of a neurological examination can be attempted by mere observation. Subtle changes that are observed may help in early diagnosing and prompt therapy. In this article, Dr. YK Amdekar discusses cases that hint at neurological abnormalities.

In clinical practice, doctors are rarely required to conduct a detailed neurological examination. An obvious neurology problem is referred to a specialist but subtle neurological signs may be missed in the initial stages. However, a large part of the neurological examination can be possible only with observation, the exception being the sensory system, superficial and deep reflexes. Hence, it is worth developing observational skills that can almost screen probable neurological diseases in the early stage which in turn would help with timely management.

Observe relevant clues

1. Change in sensorium- Any subtle change in behaviour must be noted as it may suggest oncoming encephalopathy. Initial change can be in the form of a confused state, irrelevant talking or behaviour, lethargy or sleepiness, undue irritability. The cause of such a change may be a brain stroke or dehydration and electrolyte-acid-base disturbances.
2. Meningeal irritation- Stiff neck, irritability (due to headache) may point to meningeal irritation that may be due to intracranial infection or subarachnoid haemorrhage.
3. Cranial nerves
   1. Unilateral squint may indicate an effect of the 3rd, 4th or 6th cranial nerve. Eye movements can localise the lesion to one or more of these nerves.
   2. Ptosis, or drooping of the eyelid (dilated pupil) suggests 3rd nerve involvement with the majority of eye muscles affected except lateral rectus (moves the eye laterally) and superior oblique (moves the eye downwards).
   3. Obliteration of the nasolabial fold and angle of mouth and inability to close the eyelid denotes 7th nerve palsy.
   4. Nystagmus may be due to the vestibular part of the 8th nerve affection and hearing impairment in the cochlear division.
   5. Girling sound in the throat due to pooling of secretions indicates and poor gag indicates 9th and 10th nerve affection that go together.
   6. Abnormality in tongue movements denotes 12th nerve palsy.
4. Motor system
   1. Power- Paucity of limb movement is easily noticed but even without movements, limb position can make one suspect paresis. For example, lower limbs in the abduction and lateral rotation may suggest paresis.
      1. Hemiparesis with 7th cranial nerve affection (lower part of the face involved) on the same side indicates middle cerebral artery infarction.
      2. Hemiparesis with 3rd and 4th cranial nerve affection on the opposite side suggests brain stem involvement.
      3. Hemiparesis with 6th and 7th nerve palsy denotes pontine lesion (often accompanied with tremors and ataxia due to cerebellar disease).
      4. Hemiparesis with basal cranial nerve involvement on the opposite side indicates medullar affection.
      5. Isolated one limb paresis suggests lower motor neurone affection.
      6. Paraparesis with bladder involvement denotes intraspinal disease.
   2. Tone- Stiffness and crossing of the legs indicates increased tone that is due to pyramidal or extra-pyramidal lesion while pithed frog-like position suggests hypotonia due to lower motor neurone affection or cerebellar disease (also has ataxia and tremors).
   3. Incoordination- One can observe how the patient reaches for the object that can bring out incoordination if any.
   4. Abnormal movements- Abnormal movements may be noticeable even when the patient is at rest such as tremors, chorea or athetosis. Intentional tremors as seen in cerebellar disease are brought about by movements, so also mild tremors due to any cause.
   5. Nutrition- Wasting of muscles may be visible as in the case of lower motor neurone lesion or prolonged upper motor neurone lesion due to misuse atrophy. Similarly, hypertrophy of muscles is easily noticed as in the case of muscular dystrophy.
5. Gait- When a patient is made to stand and walk, one can spot out weakness and tone abnormalities. Stance and swing must be observed and so also the way the patient turns around and moves his upper limbs while walking. *
6. Ataxia- Swaying while sitting or standing is easily noticeable that denotes cerebellar disease (intentional tremors), sensory system affection (patient sways only on closed eyes) or vestibular disorder (often acute or recurrent episodes)
7. Skull and spine-
   1. Small head size (microcephaly) with a mentally retarded look suggests severe brain affection. Occasionally, microcephaly may be seen in a normal person which is due to the autosomal dominant character (which means one of the parents also has microcephaly with normal mentation).
   2. Large head size (macrocephaly) is often due to hydrocephalus.
   3. The presence of abnormal skin lesions (swelling or hair) at the lumbosacral region suggests a probable underlying spinal defect. It would prompt one to look for any other neurological abnormality affecting lower limbs or bladder function.

Importance of observation in neurological diseases

It is clear that most part of the clinical neurological examination is possible only with observation, without touching the patient. The advantage of such observation skills in neurology is to pick up early abnormalities. Here are some case scenarios that represent why observation is important.

Case 1

A five-year-old child presented with a high fever for a day and was looking unduly lethargic. It suggests brain dysfunction. As it had happened within the first day of onset of fever, it may have been due to viral encephalitis, severe bacterial infection with shock or severe metabolic disorder triggered by fever.

Diagnosis: In all such situations, the child needs to be urgently hospitalised and investigated. It turned out to be meningococcaemia. It would be fatal if not picked up early. This child was saved.

Case 2

An eight-year-old child was being treated for acute bacterial pneumonia with intravenous antibiotics. The mother reported a state of confusion as the child was looking for her when she was just next to him.

Diagnosis: It meant early brain dysfunction. This child of pneumonia was hypoxic and required oxygenation. With universal use of oximeters, low oxygen saturation can be picked up even before the first symptom arises.

Case 3

A ten-year-old child was recovering from fever when he became drowsy suggestive of brain dysfunction. As it happened during the immediate afebrile period, it was likely to be infection-induced immune complications.

Diagnosis: It turned out to be dengue shock syndrome. The child quickly reverted to normal with fluid resuscitation.

Case 4

A two-year-old child was being treated for vomiting with an anti-emetic drug and was seen to have developed abnormal movements of the face and limbs. He was conscious with normal verbal response and there was no other neurological abnormality observed.

Diagnosis: This was a drug reaction and its abnormal movements disappeared after the withdrawal of the drug.

Case 5

A five-year-old child was brought for repeated falls while walking.

Diagnosis: Observation revealed the mild weakness of one lower limb that suggested a lower motor neurone lesion. It was confirmed to be an extra-medullary spinal tumour.

Disclaimer- The views and opinions expressed in this article are those of the author's and do not necessarily reflect the official policy or position of M3 India.