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1136 Neurologic Examination

Neurologic Examination
VetBooks.ir Procedure

Difficulty level: ♦
require most components of the peripheral
There are five main components to the neu- • Postural reactions: normal postural reactions
Overview and Goal rologic examination: sensorium, gait, postural and central nervous systems to be intact.
To evaluate a patient’s neurologic function reactions, spinal reflexes, and cranial nerves. The most reliable of the postural reactions
through clinical physical assessment of menta- The order in which the five components are is the hopping response.
tion, gait, posture, postural reactions, spinal evaluated depends on the patient’s behavior ○ Hopping response: each limb is tested by
nerve reflexes, and cranial nerve examination. and chief complaint. holding the patient so that most of the
The goal in a patient with a nervous system • Sensorium: owners are best able to evaluate weight is borne on the limb to be tested,
lesion is to establish the anatomic location of subtle changes in their animal’s behavior or and the patient is moved laterally on that
that lesion. The anatomic diagnosis will deter- sensorium. In increasing severity, sensorium limb:
mine the differential diagnosis and the choice changes are depression, lethargy, obtunda- ■ First, straddle the patient so that you
of ancillary studies to be recommended. tion, semicoma (stupor), and coma. and the patient are facing in the same
• Gait: diagnosis of gait disorders is based on direction.
Indications pattern recognition for specific anatomic sites ■ Palpate the thoracic limbs to determine
Reasons for an owner to present a patient for in the nervous system (and musculoskeletal if any denervation or disuse atrophy is
a neurologic examination: system). They are best evaluated with the present.
• Seizures (p. 903), abnormal spontaneous patient moving on grass or a rug where slip- ■ Flex and extend the limbs to determine
uncontrolled movements, pacing, circling, ping is not a problem. As a rule, changes are range of motion and muscle tone.
head pressing, tremors (p. 994) best seen with the patient walking slowly and ■ Place the paw on its dorsal surface—the
• Abnormal mentation: depressed to unrespon- taking numerous slow turns. Two qualities paw replacement test—and observe how
sive, no recognition of owner, loss of trained of paresis and three qualities of ataxia are quickly it is replaced. NOTE: This is not
habits, excreting indoors considered in gait analysis: just a test of conscious proprioception
• Abnormal gait: lame, paretic (pp. 756 and ○ Paresis (neurogenic abnormality of muscle (CP) because disorders of the UMN,
757), ataxic (p. 86), paralyzed, collapsing activity tone/strength) LMN, and/or general somatic affer-
• Loss of balance, hearing, vision (p. 123) ■ Lower motor neuron (LMN) paresis ent cutaneous receptors can result in
• Head tilt (p. 403), unable to close eyelids, causes a loss of ability to support a delay in this response. A sole CP
unable to prehend food or swallow, protruded weight, reflected in rapid, short deficit cannot be determined, and
third eyelid, pupil asymmetry, eye deviation strides with collapsing on the affected that term should be discarded from
• Regurgitation (p. 873), dyspnea (p. 879) limb. The patient walks with a lame the neurologic examination. Be aware
gait. that many normal patients may delay
Contraindications ■ Upper motor neuron (UMN) paresis in replacing the paw to its supporting
• Aggressive patient interferes with gait generation, delaying position.
• Injured patient for whom manipulation may the protraction of the affected limb and ■ Brace your own elbow on your ipsilat-
exacerbate the nervous system lesion and lengthening the stride. This form of eral knee and support the abdomen so
the examination is limited to the recumbent paresis cannot be separated from general that most of the patient’s weight is on
patient proprioceptive (GP) ataxia because of its thoracic limbs.
the close association of the caudal ■ With your other arm, pick up the
Equipment, Anesthesia projecting UMN tracts and cranial patient’s thoracic limb on that side, and
• Quiet area projecting GP tracts in any transverse push the patient laterally away from
• Outdoor area or a room large enough to section of the spinal cord and caudal that limb. This forces the patient to
evaluate the gait brainstem. hop on the opposite thoracic limb.
• Nonskid floor surface; indoor-outdoor carpet ○ Ataxia (incoordination) ■ After three or four hops, do not move,
works well ■ GP ataxia creates the appearance of the but just reverse both thoracic limbs
• Pleximeter, source of bright light, small patient not knowing where its limb(s) so that you can pick up the opposite
forceps is/are located in space. This also results thoracic limb and hop the patient back
in a delay in protraction of the limb and on the contralateral thoracic limb.
Anticipated Time a prolonged stride, and the patient may ■ Compare one thoracic limb with the
About 10-20 minutes show an excessive medial (adduction) other only when it is being hopped
or lateral (abduction) excursion of the laterally.
Preparation: Important limb as it is protracted. Both UMN ■ Move back to the pelvic limbs, and
Checkpoints and GP deficits can cause the patient to repeat the muscle palpation, range of
• Assess for contraindications (see above). occasionally stand on the dorsal aspect motion, and paw replacement.
• NOTE: To avoid introducing bias, review of its paw. ■ At that time, check the tail and anus
existing diagnostic test results (e.g., lab tests, ■ Vestibular ataxia is evident when for tone and reflex response.
radiographs) after performing the neurologic the patient has a head tilt and drifts ■ Stand beside the patient, and with one
examination. or stumbles to the side from loss of arm placed under the sternum, pick
balance. the patient up so it is standing on its
Possible Complications and ■ Cerebellar ataxia is characterized by a pelvic limbs.
Common Errors to Avoid delay in protraction and an excessive ■ Pick up the closest pelvic limb, and
• Do not be biased by a single abnormality. response, a dysmetric abrupt gait gen- push the patient away so that it hops
• Do the same methodical, thorough evaluation eration that usually is associated with laterally on the opposite pelvic limb.
on every patient, regardless of the complaint some balance loss. As a rule, sudden ■ Repeat this maneuver on the opposite
or the signs that are evident. flexion movements predominate. side.

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