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Tetraplegia/Tetraparesis 967

Tetraplegia/Tetraparesis Client Education
Sheet
VetBooks.ir Diseases and Disorders
PHYSICAL EXAM FINDINGS
BASIC INFORMATION
• Varies (see specific diseases) DIAGNOSIS
Definition • It is important to neuroanatomically localize Diagnostic Overview
The suffix -plegia signifies complete paralysis; the lesion (p. 1136). Tetraparesis/tetraplegia implies a neurologic
-paresis signifies muscle weakness. Either may • Tetraplegia or tetraparesis can be seen with syndrome; severe systemic disturbances
manifest with upper motor neuron (UMN) or UMN and/or LMN signs. must be ruled out with physical exam and
lower motor neuron (LMN) signs. Tetraplegia • Symmetry or asymmetry of paresis should be minimal laboratory testing (CBC, chemistry
is complete paralysis of all limbs; tetraparesis noted because this finding may help narrow profile). A neurologic exam is pivotal in
is weakness of all limbs. the differential diagnosis. establishing an anatomic diagnosis, which
• Animals may have UMN or LMN bladder, narrows the differential diagnosis and allows
Synonyms depending on the neuroanatomic location the clinician to choose specific diagnostic
• Tetraplegia: quadriplegia of the lesion(s). tests.
• Tetraparesis: quadriparesis • Animals with tetraplegia or tetraparesis have
a disease involving one of the following Differential Diagnosis
Epidemiology regions: Intracranial:
SPECIES, AGE, SEX ○ Tetraplegia or tetraparesis to all four • Neoplasia
Dogs and cats of any age and either sex limbs • Vascular (e.g., cerebrovascular accident)
Bilateral cerebral cortex • Trauma
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GENETICS, BREED PREDISPOSITION ■ Bilateral brainstem • Encephalitis (various causes, including
• Toy-breed dogs: atlantoaxial instability ■ Bilateral cervical spinal cord infectious and immune-mediated menin-
• Older Doberman pinschers, young Great ○ Tetraplegia or tetraparesis with hindlimb goencephalitis of unknown origin [MUE]
Danes, and other large-breed dogs: cervical UMN (as above) and forelimb LMN signs diseases)
spondylomyelopathy (decreased muscle tone, hyporeflexia) • Hydrocephalus
• Chondrodystrophic dog breeds: cervical ■ Bilateral C6-T2 spinal cord involvement • Postictal state
intervertebral disc protrusion ○ Tetraplegia or tetraparesis with LMN signs Cervical spinal cord:
• Burmese cats: hypokalemia to all four limbs • Intervertebral disc disease
• Labrador retrievers: exercise-induced collapse ■ Disease affecting motor neurons of • Trauma
• Various cat/dog breeds: breed-associated C6-T2 and L4-S2 • Cervical spondylopathy
motor neuron diseases ■ Disease affecting peripheral nerves • Atlantoaxial instability
• Various cat/dog breeds: breed-associated (motor component) of all four • Myelitis (various causes, including infectious
muscular dystrophies and myopathies limbs and immune-mediated [MUE] diseases)
Disease affecting the neuromuscular • Osteochondromatosis
■
RISK FACTORS junction • Synovial or arachnoid cysts
• Exposure to carrion: botulism (dogs) ■ Disease affecting the skeletal muscle Peripheral nerves or neuromuscular junction:
• Exposure to toxins (e.g., 2,4-D herbicide; • If one particular region cannot be • Tick paralysis
organophosphates/carbamates) logically identified, disease process is likely • Idiopathic polyradiculoneuritis
• Penetrating wounds (tetanus) multifocal. • Snake or spider envenomation
• Areas endemic for coral snakes; black widow • Myasthenia gravis
spiders (Latrodectus spp); Dermacentor spp, Etiology and Pathophysiology • Botulism
Amblyomma spp, and Ixodes spp of ticks (tick • UMNs are found in the brain and control • Hypothyroidism
paralysis) LMNs. • Various toxins
• LMNs transmit information from the central Muscle:
Clinical Presentation nervous system (CNS) to an effector organ- • Immune-mediated polymyositis (primary
HISTORY, CHIEF COMPLAINT like skeletal muscle. or secondary to another disease, such as
Tetraplegia: • Conditions affecting UMNs and/or their neoplasia)
• Inability to bear weight, voluntarily move axons result in UMN signs. • Hypokalemia
limbs, or ambulate ○ Paralysis or paresis • Endocrine disease (hyperthyroidism [cats],
Tetraparesis: ○ Normal to increased spinal reflexes hypothyroidism, hyperadrenocorticism)
• Impaired locomotion, ranging from mild ○ Later-onset muscle atrophy (disuse • Various breed-related muscular dystrophies
weakness or spasticity (usually with ataxia) atrophy) and myopathies
to recumbency ○ Normal to increased muscle tone
• Ability to voluntarily move limbs even if • Conditions that affect LMNs, their axons, Initial Database
recumbent and the neuromuscular junction result in • Assess patient stability (some may present
• Tetraparetic/tetraplegic animals with diseases LMN signs. with impaired respiratory function and/or
involving the cerebral cortex and/or brain- ○ Paralysis or paresis cardiac arrhythmias)
stem show other abnormal neurologic signs. ○ Decreased or absent spinal reflexes • Complete physical and neurologic exams
○ Abnormal mentation and/or seizures ○ Rapid, severe muscle atrophy (neurogenic • CBC, serum chemistry profile, and urinalysis
(cerebral cortex or diencephalon) atrophy) for assessment of systemic causes and pre-
○ Dullness, stupor, or coma (brainstem) (i.e., ○ Decreased muscle tone anesthetic evaluation
midbrain, pons, medulla oblongata) • Primary or systemic diseases affecting
○ Cranial nerve disturbances (brainstem) skeletal muscle cause impaired muscular Advanced or Confirmatory Testing
○ Abnormal respiratory character (brain, function and can manifest as tetraplegia or Choice of test depends on neurolocalization
cervical spinal cord) tetraparesis. and most likely diagnosis.

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