ICVA Equine Lameness and Neurology 2 — Questions and Answers
Question 1: Which nerve block is used to desensitize the palmar fetlock and pastern region in the horse?
- Abaxial sesamoid nerve block (Correct answer)
- Low 4-point nerve block
- High palmar nerve block
- Median nerve block
Correct answer: Abaxial sesamoid nerve block
The abaxial sesamoid nerve block desensitizes the palmar and plantar fetlock, pastern, and foot regions.
Question 2: A horse with equine protozoal myeloencephalitis (EPM) most commonly shows which clinical sign?
- Bilateral forelimb lameness
- Asymmetric ataxia and muscle atrophy (Correct answer)
- Facial nerve paralysis only
- Hypermetria in all four limbs equally
Correct answer: Asymmetric ataxia and muscle atrophy
EPM typically causes asymmetric ataxia, weakness, and focal muscle atrophy due to multifocal CNS lesions.
Question 3: What is the most reliable imaging modality for evaluating the navicular bone and surrounding soft tissues in equine foot lameness?
- Radiography
- Ultrasonography
- MRI (Correct answer)
- Nuclear scintigraphy
Correct answer: MRI
MRI provides superior soft tissue and bone detail of the foot, including the navicular bone, impar ligament, and deep digital flexor tendon.
Question 4: Stringhalt in horses is characterized by which gait abnormality?
- Exaggerated involuntary hindlimb flexion during forward movement (Correct answer)
- Dragging of the forelimbs during trot
- Circumduction of the hindlimbs at walk
- Intermittent weight-shifting between forelimbs at rest
Correct answer: Exaggerated involuntary hindlimb flexion during forward movement
Stringhalt is characterized by sudden, exaggerated, involuntary flexion of one or both hindlimbs during movement.
Question 5: Which structure is most commonly injured in horses diagnosed with hindlimb proximal suspensory desmitis?
- Plantar ligament
- Origin of the suspensory ligament at the proximal palmar metacarpus (Correct answer)
- Distal sesamoidean ligaments
- Straight sesamoidean ligament
Correct answer: Origin of the suspensory ligament at the proximal palmar metacarpus
Proximal suspensory desmitis involves injury to the origin of the suspensory ligament at the proximal palmar or plantar cannon bone.
Question 6: In the AAEP lameness grading scale, a grade 3 lameness is best described as:
- Lameness difficult to observe at trot but consistently present
- Consistently observable lameness at trot under all circumstances (Correct answer)
- Lameness only visible at canter or with specific manipulation
- Non-weight-bearing lameness
Correct answer: Consistently observable lameness at trot under all circumstances
AAEP grade 3 lameness is consistently observable at the trot under all circumstances, including straight lines and circles.
Question 7: Wobbler syndrome (cervical vertebral stenotic myelopathy) in horses is most definitively diagnosed by which method?
- Rectal palpation
- Myelography or CT myelography (Correct answer)
- CSF tap alone
- Serum vitamin E levels
Correct answer: Myelography or CT myelography
Myelography or CT myelography demonstrates spinal cord compression at the affected cervical vertebral site.
ICVA Equine Lameness and Neurology 2
Which nerve block is used to desensitize the palmar fetlock and pastern region in the horse?