6.Examination of the nervous system of the horse Flashcards
what are the general considerations?
- Is it necessary to use life saving methods?
- Is it a real nervous system problem?
- Is it a cerebral, spinal or peripheral dysfunction?
- Is it an acute or a chronic process?
- Do you suspect any infectious disease?
What are the types of neurological diagnosis?
- Functional or symptomatic
- Anatomical
- Pathological
- Aetiological
Why is history taking important?
- Limitations of the examination
- Characteristic of neuropathies
- Missing subjective information
- Infectious diseases of the nervous system
what are som disturbing factors?
- Restraint
- Sedatives
- Environment
Methods of physical examination:
- Inspection
- Palpation
- Postural reactions
- Vertebral reflexes
- Cranial nerves
- Sensitivity
- Pain perception
Ancillary diagnostic aids:
• Neuroradiography 1. Plain 2.Myelography 3. Angiography (cerebral and vertebral) • Nuclear scintigraphy • Computed tomography • Magnetic resonance imaging • Electroencephalography (electromyelography) • Laboratory tests (blood, urine, CSF)
Explain the structure of the physical examination:
- Head
- Behaviour
- Mental status
- Head posture and coordination
- Cranial nerves
- Gait and posture
- Neck and forelimbs
- Trunk and hind limbs
- Tail and anus
- Cerebrum
- Brain stem
- Cerebellum
- Spinal cord
- Peripheral nerves (and muscles)
Where is the 4 functional areas of the spinal cord where lesions often show up?
c1-c5, c6-T2, T3-L3, L4-S3, caudal
What are the clinical signs in this area: C1-C5
Tetraparesis/plegia, sometimes neck pain, normal to exaggerated spinal reflexes
What are the clinical signs in this area: C6-T2
Tetraparesis/plegia, sometimes neck pain, decreased to absent thoracic limb spinal reflexes, normal to exaggerated spinal reflexes - pelvic limbs
What are the clinical signs in this area: T3-L3
Paraparesis/plegia, sometimes back pain, normal thoracic limb spinal reflexes. Normal to exaggerated pelvic limbs spinal reflexes
What are the clinical signs in this area: L4-S3
Paraparesis/plegia, sometimes lower back pain, normal thoracic limb spinal reflexes. decreased to absent spinal reflexes -pelvic limbs
What are the clinical signs in this area
Paresis/plegia of tail, decreased tail tone, decreased tail sensation
What is important to take into consideration when checking behaviour?
- Typical reactions
- Age
- Breed
- Sex
- Abnormal reactions
- Stable vices
What are the three states of increased reactivity?
- Excitement
- Agitation
- Aggression
Name the categories of consciousness:
Alert, depressed, delerium/dementia, semicomatose stuporous, comatose
Explain delerium,dementia ;
Responsive to environmental stimuli, but responses are not clearly directed to the stimuli
Explain semicomatose stuporous:
Remains unresponsive to environmental stimuli but responsive to painful sensation
Explain comatose:
non-responsive to either environmental or painful stimulation
What head postures and coordinations are we looking for?
- Position and movements of the atlantooccipital joint
* Control of cerebrum, cerebellum and vestibular system
What can we see when there is a vestibular lesion?
Head tilt
What can we see when there is a cerebral lesion?
Deviation of head and neck toward the side of the lesion
What can we see when there is a cerebrellar lesion?
Jerky movements during voluntary motion and fine tremor when at rest (intention tremor)
How do we test the olfactory nerve?
Evaluation of smell
Why do we test the optic nerve?
- Menace reflex
* Test for vision
how do we test the oculomotor nerve?
• Pupillary light reflexes
Cranial nerves:
Trigeminal nerve controls:
- Evaluation of facial cutaneous sensation
- Palpebral reflex
- Corneal reflex
- Ability to chew, movements of the jaw
Facial nerve controls:
- Evaluation of facial symmetry and movement
* Palpebral and corneal reflex
Vestibulocochlear nerve are important for:
- Evaluation of hearing
* Evaluation of balance
Glossopharyngeal, vagus and accessory nerves are important for :
• Swallowing reflex
How do we test the swallowing reflex?
- Feeding and watering test • Nasogastric tubing
- Endoscopy
- Slap test
Why is the hypoglossal nerve important to check?
for the evaluation of tongue function
Explain ataxia
lack of coordination
Explain dysmetria
an error in trajectory due to an abnormal range, rate, and/or force of motion
What is hypometria and hypermetria?
Hypometria: voluntary movement is shorter than the intended goal; too little joint movement
• Hypermetria: voluntary movement results in overreaching of the intended goal; excessive joint movement
What is Paresis:
muscle weakness resulting from neurologic dysfunction
what is Paralysis:
inability to move voluntarily
What do we check when we evaluate the neck and forelimbs?
- Neck mobility
- Cervicoauricular (cervicofacial) reflex
- Cervical cutaneous sensation
- Deep pain perception
- Sway reaction
- Resistance to dorsal pressure on the withers
- Thoracic limb postural reactions
- Positioning limbs in a crossed position (correction test)
- Sideways hopping
what do we check when we evaluate the trunk and hind limbs?
• Cutaneous sensation • Deep pain perception • Sway reaction • Resistance to dorsal pressure on the lumbar region • Pelvic limb postural reactions -Positioning limbs in a crossed position (not reliable) -Sideways hopping
Evaluation of the tail and anus
- Tail tone
* Perineal reflex
Recumbent horses (reflexes)
- Forelimb flexor reflex
- Biceps reflex
- Triceps reflex
- Hind limb flexor reflex
- Tibial (plantar aspect of the metatarsus)
- Peroneal (dorsal part of the tarsus and metatarsus)
- Femoral (medial thigh region)
- Patellar reflex
If the horse can lift only its head, the lesion is —–
in the cranial cervical region
If the horse can raise its head and neck, the lesion———-
is in the caudal cervical region
If the horse cannot rise into a sitting position (”dog-sitting” position), the lesion is——–
in the cervical cord
If the thoracic limbs are functional, the lesion is ————
is caudal to T2
If the deficit is in the trunk or hind limbs, the lesion is
located
between T2 and S2
Localised sweating indicates a lesion in
the descending sympathetic tracts
