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The primary aim of a neurologic examination is to confirm whether a neurologic abnormality exists. Because omission of parts is the most common mistake made during the neurologic examination, the order in which the examination is performed becomes important. Here, we provide a precise practical format that is logical in sequence, easy to remember with practice, and emphasizes the need for an anatomic diagnosis (Where is the lesion?) to be made before an etiologic diagnosis (What is the cause of the condition?) is made. The rationale for the sequence of the examination presented here is as follows: first, it starts at the head and proceeds caudally to the tail; second, it is used for patients of all sizes and species, whether the patient is ambulatory or recumbent; third, it considers the anatomic location of lesions as the examination proceeds. Even if parts of the examination must be omitted because of the nature of the patient, suspicion of fracture, or financial constraints, the sequence ought to be followed mentally. Frequently, the presence of a neurologic lesion(s) cannot be deduced until the end of a thorough neurologic examination.

In practice, some experienced neurologists will undertake a preliminary examination along these lines and then perform a more detailed and focused study of the patient to help rule in and rule out involvement of the various parts of the nervous system. The nature of the latter will be based upon findings from the primary examination, from aspects of the examination that were overlooked or were uncertain, and from the history. During this focused assessment, it is just as important to rule out involvement of certain regions of the nervous system — e.g., forebrain, cervical spinal cord — as it is to define those components that are likely affected.

An outline of the recommended format for the neurologic examination of large animals, based on the evaluation of the adult horse, is given in Table 2.2, along with a summative description of the evaluation of cranial nerve function in Table 2.3 and of the gait evaluation in Table 2.4. A format for recording results of the neurologic examination can be very useful, and the format of this can be adapted to the examiner’s preference. Some prefer a detailed checklist for most of the observations and tests carried out, others utilize an anatomic breakdown of most of the testing and observations, while some prefer a blank sheet to simply record abnormal findings. An example of a neurologic examination recording form, based on both anatomic sites and many of the tests and observations to record results of, is provided in Figure 2.1. Some comments as to differences important to recall when evaluating neonates also are indicated. Such a format is very applicable to other large animal species, modified according to practical circumstances such as size, containment and behavior of the patient, monetary value, and the disease processes possibly involved such as zoonoses and trauma.

We encourage those readers who are not reasonably well practiced in performing and recording neurologic examinations and in both normal and diseased patients, to practice on a friendly, neighborhood, mid‐sized dog. The approach for such an examination will be as for a calf, foal, lamb, kid, or (bless their little larynges) piglets. Should the practice dog or such patient be small enough, the close aspects of the procedure used are readily performed by sitting with the patient on one’s knees or having the patient on a table. Mid‐sized patients of these types can be examined by standing straddled above the dorsum of the patient while supporting the head, both for restraint and comfort.

Below is given an overview of the practicalities of performing an efficient neurologic examination followed by assistance in interpreting some of the findings.

We make no excuse for the rather excessive detail included in this chapter. Although one can always go to E‐references for factual information on disease processes, above all else it is the specific findings from an accurate and repeated neurologic examination, with only then careful reflection on the significance of the findings, that successful and accurate diagnoses are made.

If all else fails, examine the patient again!

Table 2.2 Outline of basic format for the neurologic examination, based on that for the horse

Region	Evaluation	Sites evaluated	Points to emphasize
Adult	Neonate <2 weeks
Head	Behavior	Forebrain	History and owner’s understanding Seizures, especially mild and focal. VIDEO Subtle asymmetry in menace and nasal sensation	Quick adjustment ~2–7 days Paralytic state with cradling Partial seizures—just face, jaw
Mentation/sensorium	Forebrain Midbrain	Response to environment Sleep attacks more common than epilepsy Cardiovascular syncope very rare	Adjustment ~24 h
Head posture and movement	Neck Forebrain—head and neck turn Vestibular—head tilt Tremor—check eyeballs	Stiff/twisted neck Head tilt (VIII) verses head turn (forebrain) Head tremor—cerebellar Head/neck ataxia—cerebellar/spinal Head shaking—trigeminal	Flexed head posture and ataxic movements normal
Cranial innervation	CN II – XII Brainstem Cervical sympathetic supply	Evaluate regions of head Fundic examination Repeat test for subtle asymmetries Reevaluate when totally relaxed	Menace deficit <7 days Eye rotation dorsomedial
Body	Neck and forelimbs	C1–T2	Particularly asymmetry Only flexor reflex useful Hopping	All reflexes Hyperreflexia normal Crossed extension normal
Trunk and hindlimbs	T3–S2 L4—femoral n. L5—cranial gluteal n. L6–S1—sciatic n.	Particularly asymmetry Patellar reflexes usefulFlexor reflex useful	All reflexes Hyperreflexia Crossed extensor reflex Extensor thrust response
Tail	Ca1+	Extension and flexion
Perineum, anus, rectum, and bladder	S1–5	S1–2 is common fracture site
Gait and posture	ORTHOPEDIC PROBLEMS!	Neuromusculoskeletal	VIDEO! Shoulder and hip atrophy common Possible analgesic trial	SEPSIS!
Positional CP deficits	Brainstem, spinal cord, and sensory nerves	Manual placement of feet/limbs noncontributory	Prematurity
Extensor weakness	Brainstem, spinal cord, and PNS	Especially final motor neuron lesion	Extensor strength dominant
Flexor weakness	Brainstem, spinal cord, and PNS
Ataxia	Spinal ataxia	Irregular position and placement
Cerebellar ataxia	Hypermetria characteristic; F > H	Normal to degree
Vestibular gait	Crouched posture Deliberate (predictable) stepping Wide‐based, staggering gait	Normal to degree

CP, conscious proprioception; CN, cranial nerve.