The neurological system controls cognitive/voluntary behavioral processes and the subconscious/involuntary bodily functions. A neurologic examination is organized into six major areas: mental status (also read: MSE), cranial nerves, sensory systems, motor systems, cerebellar function, and reflexes.
Neurologic Exam
- Health History: head injury, loss of consciousness, headaches, vertigo, dizziness, fainting, paresthesia, weakness, recent changes in ADL performance, change in mental status, vision, speech, gait abnormalities (balance, coordination, falls), drooling, dysphagia, seizures, tremors, infections, meningitis, encephalitis, circulatory problems, medications that may affect any faculty of the nervous system (coordination, mental status, etc.)
- Family History: hereditary disorders, Tay-Sachs Disease, muscular dystrophy, PKU, mental retardation, Dementia of the Alzheimer’s Type
- Developmental Considerations
- General Signs and Symptoms: memory loss, disorientation, changes in the level of consciousness, seizures, speech or swallowing difficulties, vision and papillary changes, dizziness, headache/pain, weakness, ataxia, tremors, numbness, tingling, paralysis, nausea and vomiting, bowel or bladder difficulties
- Mental Status Examination
- Physical Examination
- Level of Consciousness (GCS)
- Motor Function
- Pupillary Function/Eye Movements
- Vital Signs
- Laboratory and Diagnostic Testing
Mental Status
Level of Consciousness (LOC) is the most important aspect of a neurologic examination, as LOC is often the first to deteriorate in a pathologic process. However, changes are often subtle and require careful monitoring. There are two components to consciousness:
- Arousal (Alertness)
- Awareness (Content): assessed via orientation vs. disorientation. The patient is questioned (in varying sequences) about their orientation to person, place, time, or situation.
Glasgow Coma Scale
A three-category test to score a patient’s mental functioning out of 15 (lowest being 3). A score of 13 to 15 may only show for minor brain injuries, 9 to 12 for moderate brain injuries, and 3 to 8 for severe brain injuries.
| Criteria and Scoring | ||
|---|---|---|
| Response | Scale | Score |
| Eye Opening Response | Eyes open spontaneously | 4 |
| Eyes open to verbal command, speech, or shout | 3 | |
| Eyes open to pain (not applied to face) | 2 | |
| No eye opening | 1 | |
| Verbal Response | Oriented | 5 |
| Confused conversation, but able to answer questions | 4 | |
| Inappropriate responses, words discernible | 3 | |
| Incomprehensible sounds or speech | 2 | |
| No verbal response | 1 | |
| Motor Response | Obeys commands for movement | 6 |
| Purposeful movement to painful stimulus | 5 | |
| Withdraws from pain | 4 | |
| Abnormal (spastic) flexion, decorticate posture | 3 | |
| Extensor (rigid) response, decerebrate posture | 2 | |
| No motor response | 1 | |
| Category | Description |
|---|---|
| Alert/Full Consciousness | Responds immediately to minimal external (visual, tactile, auditory) stimuli |
| Lethargic | A state of drowsiness; the client needs increased external stimuli to be awakened but remains easily aroused. Verbal, mental, and motor responses are slow or sluggish. |
| Obtunded | Very drowsy when not stimulated, but is able to follow simple commands when stimulated vigorously (shaken, shouting). Verbal responses are simple (few words) and the client will drift back to sleep between periods of stimulation. |
| Stuporous | Awakens only to vigorous and continuous noxious (painful) stimulation. There is minimal spontaneous movement; motor response to pain is normal but verbal responses are minimal and often incomprehensible (moaning, groaning) |
| Light Coma | Vigorous stimulation does not produce a response. Only motor responses to noxious stimuli are still purposeful. |
| Deep Coma | Same as light coma, but Motor responses to noxious stimuli are absent. |
Cranial Nerve Testing
| Nerve | Test |
|---|---|
| Olfactory Nerve (I) | Skipped unless facial trauma is present; smell test: have the patient close their eyes and identify a common smell with alternating nostrils e.g. a chocolate bar. |
| Optic Nerve (II) | Identify fingers or movements in all quadrants and periphery in each eye; blink to threat in temporal and nasal quadrants if unable to participate, or by using a Snellen chart or Jaeger card to check visual acuity. |
| Oculomotor Nerve (III) | Move eyes in all directions except outward, down, and inward. The patient should be able to open the eyelid and the pupil constricts when lit.. |
| Trochlear Nerve (IV) | Move eyes downward and inward. |
| Trigeminal Nerve (V) | Split into three branches (sensation to face, cornea, and scalp). To test, open the jaw against resistance. |
| Abducens Nerve (VI) | Move eyes outward |
| Facial Nerve (VII) | Moves the face (smile, frown, raise eyebrows, show teeth, puff out cheeks, purse lips, close eyes against resistance); is able to taste. |
| Acoustic Nerve (VIII) | Split into two branches (acoustic, vestibular). Whisper, Weber and Rinne tests and Watch-tick Test for hearing. Romberg Test (stand straight, feet together, arms to the side, then close eyes) for balance. |
| Glossopharyngeal Nerve (IX) | Moves the pharynx (swallow, talk, gag) |
| Vagus Nerve (X) | Voice Quality |
| Spinal Accessory Nerve (XI) | Turns the head and elevates shoulders (both can be done against resistance). Note symmetry. |
| Hypoglossal Nerve (XII) | Protrude the tongue. It should be midline, stable, and has no wasting. Have the patient say “light, tight, dynamite”. Speech should be clear and distinct. |
- Whisper to the patient (from behind), and ask them to repeat what was said.
- Weber’s Test (head) and Rinne’s Test (mastoid, air conduction > bone conduction) are done with a tuning fork.
- Romberg’s Test: stand straight with feet together, arms at the side. Close the eyes and see if a loss of balance is found (positive Romberg sign)
Cerebellar Testing
The cerebellum fine tunes motor activity and assists with balance. As such, dysfunction of the cerebellum results in a loss of coordination (ataxia) and problems with gait. It is split between two hemispheres, with either side controlling their respective sides. For testing, there are various methods, but even just one will suffice.
- Finger to Nose Testing: With the patient seated, position the index finger at a point in space in front of the patient. The patient should then trace an imaginary line from your finger to their nose. After each attempt, reposition the finger.
- The patient should be able to do this at a reasonable rate of speed, in a straight path, and hit the end points accurately. If they miss the mark (dysmetria), it may be indicative of disease.
- Rapid Alternating Finger Movements: ask the patient to touch the tips of each finger to the thumb of the same hand, for both hands.
- The movement should be fluid and accurate. If they are unable to perform this (dysdiaokinesia) may be indicative of cerebellar disease.
- Rapid Alternating Hand Movements: ask the patient to touch the ventral and dorsal side of one hand repeatedly against their thigh, for both hands.
- Should be done with speed and accuracy. Inability (dysdiadokinesia) may also be indicative of cerebellar disease.
- Heel to Shin testing: direct the patient to trace a straight line along the shin (knee to ankle) with their heel.
- Straight, and at an appropriate rate should be noted.
- Romberg’s Test: have the patient stand with feet together and arms at the side.
- If a loss of balance is noted, it is interpreted as a positive Romberg sign.
- Tandem Gait: have the patient walk a straight line heel-to-toe for each step. Other abnormalities may only manifest when the patient is asked to walk on their heels, toes, or the insides or outsides of their feet, to stand or hop on one leg, or to walk up stairs.
- Patients with truncal ataxia caused by damage to the cerebellar vermis or associated pathways will have difficulty with this task (tends to have a wide-based, unsteady gait, and becomes more unsteady with close feet).
- Gait involves multiple sensory and motor systems (vision, proprioception, lower and upper motor neurons, basal ganglia, the cerebellum, and higher-order motor planning)
Deep Tendon Reflexes
A muscle tendon, when tapped briskly, normally immediately contracts due to a two-neuron reflex arc involving the spinal or brain stem segment that innervates the muscle.
- The afferent neuron whose cell body lies in a dorsal root ganglion innervates the muscle or Golgi tendon organ associated with the muscle, and the efferent neuron is an alpha motoneuron in the sensory input of the cord.
- The cerebral cortex and a number of brainstem nuclei exert influence over the sensory input of the muscle spindles by means of the gamma motoneurons that are located in the anterior horn; these neurons supply a set of muscle fibers that control the length of the muscle spindle itself.
- Hyporeflexia is an absent or diminished response to tapping. This may result from disease in one or more aspects of the two-neuron reflex arc.
- Hyperreflexia is a hyperactive or repeating (clonic) reflexes. These indicate an interruption of corticospinal and other descending pathways that influence the reflex arc due to a suprasegmental lesion (above the level of the spinal reflex pathways).
| Grading | Description |
|---|---|
| 0 | No response. Always abnormal |
| 1+ | A slight, but present response. May or may not be normal. |
| 2+ | A brisk response. Normal |
| 3+ | A very brisk response. May or may not be normal. |
| 4+ | A tap elicits clonus. Always abnormal. |
- Abnormality of 1+ or 3+ results may be determined by reflex history, type, and associated findings (muscle tone, strength, disease)
- Asymmetry of reflexes suggest abnormality.
- Bicep Reflex:
- Flex the patient’s arm at the elbow and rest his forearm on his thigh with the palm up.
- Place the thumb firmly on the biceps tendon in the antecubital fossa.
- Strike the thumb with the hammer.
- The forearm will flex at the elbow, and the biceps muscle should contract.
- Triceps Reflex:
- Lift the patient’s (relaxed) arm to the side (hold at the elbow), facing downward at (normally) a 90 degree angle.
- Strike the olecranon (where the triceps tendon insertion is located).
- Extension of the arm should be noted.
- Brachioradialis Reflex:
- Support the arm. Identify the brachioradialis tendon at the wrist. It inserts at the base of the styloid process of the radius, usually about 1 cm lateral to the radical artery.
- Place the thumb of the hand on the biceps tendon while tapping the brachioradialis tendon with the other hand.
- Brachioradialis reflex: flexion and supination of the forearm
- Biceps reflex: flexion of the forearm
- Finger jerk: flexion of the fingers.
- Patellar Reflex (Knee Jerk): with the knees hanging, place one hand on the quadriceps to feel contraction.
- If in bed, slightly flex the knee by placing your forearm under both knees by contraction of the quadriceps with extension of the lower leg.
- Note for hyperreflexia (INC)
- Use the Jendrassik maneuver if no response is noted. Flex and form two hooks with each hand and pull them apart from each other while also clenching teeth. This reduces descending inhibitory pathways in the spine and exaggerates spinal reflex responses.
- Achilles Reflex (Ankle Jerk): have the patient sit, place one hand under the sole and dorsiflex the foot slightly. Tap on the Achilles tendon just above its insertion on the calcaneus.
- If no response is found, have the client kneel on a chair with the knee facing the back of the chair, with the feet protruding. Tap on the tendon, and note a slight dorsiflexion.
- Use the Jendrassik maneuver if no response is noted.
Brainstem Reflexes
- Oculo-Cephalic Reflex (OCR): reflex eye movement that stabilizes the images on the retina during head movement (eye movement in the direction opposite to head movement). Absence may result from severe brain damage and brain death.
- Vestibulo-Ocular Reflex (Caloric Reflex Test): irrigation of cold water or air into the external ear canal, after which the eyes should move to the same side as the irrigation. The same, but with warm, will result with the eyes moving opposite of the irrigated side.
- If abnormal i.e. eyes move away from cold, and eyes move towards warm, then nystagmus is present. This implies brain stem injury or disease.