Page 763 - Clinical Small Animal Internal Medicine

68 The Neurologic Examination 731

Examination Gait and Posture
VetBooks.ir The neurologic examination can be divided into five Examination of the gait should be performed in a place

where the patient can be walked with a leash and where
parts.
the surface is not slippery. Most hospital floors have a
very slippery surface, which facilitates cleaning but is
1) Sensorium – mental attitude
2) Gait and posture poor for evaluating a gait disorder and can be dangerous
3) Postural reactions if the patient slips and falls. A washable carpet is very
4) Muscle tone, size, and spinal nerve reflexes useful for small animals and can be rolled up between
5) Cranial nerves examinations. If you are constructing a small animal
hospital, you should consider having a covered area with
The order in which these parts are performed is usually a specialized surface used in playgrounds that is rela-
determined by the degree of patient cooperation and tively soft, provides excellent traction for the patient,
your preference. We usually perform the examination and is easily cleaned. The material is called Vitriturf®
in the order listed. However, if the patient is resting and is available from Hanover Specialties, Inc., Hauppauge,
comfortably in its cage, performing the cranial nerve New York.
examination first may be preferable. If the patient is Observe the patient while it is standing for a head tilt,
excited or apprehensive, performing the cranial nerve lowered position of the neck, trembling, degree of tarsal
examination may be more convenient after the patient extension, and tail position. You should evaluate the gait
has been handled for the examination of its gait, pos- both as you lead the patient and as an assistant leads the
tural reactions, and spinal nerve reflexes. patient. Most deficits are best seen during a slow walk
and as it turns. Walk the animal back and forth in a
straight line and in circles in each direction. Observe the
Sensorium – Mental Attitude patient from all directions. In our opinion, most abnor-
malities are best seen from a side view. Be aware of
An assessment should be made and recorded of the
patient’s sensorium, its mental attitude and response to breed characteristics that influence the posture and gait.
the immediate environment, and attitude to being The overflexed tarsus in German shepherd dogs is an
handled by you. The owner is the best judge of subtle example.
changes in the patient’s behavior in its normal environ- Is your patient unwilling or unable to move normally?
ment. Be sure to explore this issue when you obtain the When you see a gait disorder, this question is the first
history. Considerable patient variation exists in how one that you need to answer. This circumstance is espe-
alert and responsive the patient may be in the examina- cially true when the patient is short strided or does not
tion room of a veterinary hospital. Do not mistake a support weight well on one or more limbs. A loss of
very laidback behavior for depression. Descriptive support from a femoral or radial nerve disorder will
terms for this portion of your examination include alert mimic a severe painful disorder causing a reluctance to
and responsive, depressed, lethargic, obtunded, semi- bear weight.
coma (stupor), and coma. Other descriptions include Pattern recognition is critical in evaluating gait disorders.
acting vague, disoriented, hyperactive, propulsive, and With experience, clinicians recognize specific patterns
aggressive. in abnormal gaits that suggest an anatomic diagnosis.
As a rule, alterations in the patient’s normal senso- These patterns can be described but observing them
rium reflect disturbances in the ascending reticular acti- on videos is the best way to learn them. See www.
vating system (ARAS) and limbic system components of neurovideos.vet.cornell.edu. These patterns have five
the cerebrum or rostral brainstem. Be sure to evaluate components, consisting of two qualities of paresis and
the sensorium of a recumbent patient thoroughly. three qualities of ataxia.
Recumbency from diffuse neuromuscular disease or Paresis is defined as “weakness” in the dictionary, but
focal cervical spinal cord disease will not alter the in clinical neurology, it is defined as “a deficiency in the
patient’s sensorium. A dog that is recumbent with poly- generation of the gait or the ability to support weight.”
radiculoneuritis may appear to be severely depressed or This definition includes the two qualities of paresis,
lethargic because it has no voluntary movement to show which are lower motor neuron (neuromuscular) and
a response. The quality of the tetraparesis or tetraplegia upper motor neuron. Lower motor neuron (LMN) pare-
with a cervical spinal cord lesion is the same as that sis reflects degrees of difficulty in supporting weight
caused by a mid‐ to caudal brainstem lesion, but the and varies from a short stride that is easily mistaken
latter circumstance will often alter the patient’s level of for a musculoskeletal lameness to complete inability to
response to its environment. support weight, causing collapse of the limb whenever