The Neurologic Exam

Cranial Nerve Exam

I (Olfactory): Smell; unilateral loss is more significant than bilateral loss

II (Optic): Visual acuity, visual fields and ocular fundi; color vision is the first deficit of optic nerve disease

II and III (Oculomotor): Pupillary reactions

III, IV (Trochlear), and VI (Abducent): Extraocular movements; Test together; test for pupil constriction in response to light (should be bilateral); test convergence: move object closer to eyes Þ pupils should constrict and eyes should become cross eyed; CN III controls ciliary muscle, sphinceter of pupil and all external eye muscles except superior oblique and lateral rectus; CN IV controls superior oblique muscle; CN VI controls lateral rectus

V (Trigeminal): Corneal reflexes, facial sensation, and jaw movements; look for deviation of the jaw; test sensory by light touch, pin prick, warmth and cold; test eye response by gently touching side of the eye with a stick

VII (Facial): Facial Movements; test by asking patient to tightly close eyes or smile

VIII (Vestbulochlear): Hearing and balance; whisper test

IX (Glossopharyngeal and X (Vagus): Swallowing and rise of the palate, gag reflex (afferent IX, efferent X); ask patient to say "ah" Þ gag reflex is normal; dysphagia Þ difficulty swallowing

V, VII, X, XII (Hypoglossal): Voice and speech

dysarthria Þ disturbance of speech and language

dysphonia Þ altered voice production

XI (Accessory): Shoulder and neck movements

XII: Tongue symmetry and position; deviates to weak side; look for fasciculations (common in Amyotrophic Lateral Sclerosis (ALS))

Motor – examine for wasting, involuntary movements, tone, strength

Head: have patient push head against your hand
Upper Extremity: Ask patient to hold arms out in front with eyes closed and look for pronation or supination test sensory and dermatomes

C-5: hold arms out to side against force
C-6: flexion of arms against force (Biceps)
C-7: extension of arms against force (Triceps)
C-7, 8: grip test

Trunk: Ask patient to sit up from supine position
Lower Extremity: L2-S2 (not demonstrated in class)
Muscle strength is graded on 0 to 5 scale:

0 – No muscular contraction detected
1 – A barely detectable flicker or trace of contraction
2 – Active movement of body part with gravity eliminated
3 – Active movement against gravity
4 – Active movement against gravity and some resistance
5 – Active movement against full resistance without evident fatigue. (Normal)

Cerebellar Exam

Can be tested separately or within the motor exam; test balance with eyes closed (a little swaying is normal), watch walking, coordination tests Þ touch finger to nose or finger tapping

Reflexes: Deep (monosynaptic) and Superficial

Babinski Sign: stroking bottom of foot causing toe extension (normal reflex is flexion) Þ sign of upper motor neuron damage

Sensation: Light touch, pinprick, temperature, vibration and position sense

Stereognosis: ability to identify an object by touch

Astereognosis: Inability to recognize objects placed in hand

Graphesthesia: number identification; ability to identify numbers written on hand

Sensory Extinction (inattention) – recognition of only one of two concomitant stimuli