Page 78 - Canine Lameness

50 4 The Neurologic Examination

Table 4.2 (Continued)

Findings/observations Interpretation
Spinal reflexes Normal Orthopedic or UMN; less commonly some LMN
(e.g. muscle or NMJ)
Increased/exaggerated UMN, excitement, pseudohyperreflexia
Clonus UMN
Decreased LMN, limited joint mobility, age‐related (patellar),
and excitement (tense; activation of extensor
muscles)
Absent LMN, limited joint mobility, age‐related (patellar),
and less commonly UMN (i.e. spinal shock or
myelomalacia)
Cutaneous trunci reflex Cutoff: UMN, transverse thoracolumbar spinal
cord
Unilaterally absent: LMN (C8–T1 spinal cord
segments or lateral thoracic nerve), ipsilateral
Bilaterally absent: usually equivocal
Perineal LMN (S1–S3 spinal cord segments or nerves)
Perception of Normal
sensory stimuli and Increased sensitivity Orthopedic or neurologic
pain (hyperesthesia)
Reduced or absent sensitivity Neurologic
(anesthesia)
Reduced nociception Neurologic
(hypalgesia)
Absent nociception Neurologic
(analgesia)

CN, cranial nerves; GP, general proprioceptive; LMN, lower motor neuron; NMJ, neuromuscular junction; UMN,
upper motor neuron.

approaching every neurologic examination. Observation of a patient’s mentation, behavior, and
posture should begin while taking a history and the dog is able to freely move about the room.
Observations should continue throughout the examination to catch subtleties as the patient is
moved from one position to another.
Certain components, for example postural reactions (Box 4.3), should be assessed for any
patient as “screening” tests. For patients presenting with a lameness, Box 4.3 displays the mini-
mal components of the neurologic examination that should be performed. However, if the
patient or history is suggestive of neurologic dysfunction, a full neurologic examination should
be completed.

4.3.1 Mentation Status (Awareness) and Behavior
Mentation is recorded in terms of level of consciousness as alert, dull, obtunded, stuporous, or coma-
tose, and in terms of the content or quality of consciousness (e.g. inappropriate behavior). Since
most neurologic conditions causing a monoparesis or lameness will involve the PNS, mentation