ICVA - International Council for Veterinary Assessment Equine Lameness and Neurology Questions and Answers

Question 1

A 10-year-old Quarter Horse gelding presents with a 2-week history of asymmetric hindlimb ataxia, gluteal muscle atrophy, and a head tilt.
The owner reports the signs are slowly progressive.
Which of the following diagnostic approaches is considered the gold standard for an antemortem diagnosis of Equine Protozoal Myeloencephalitis (EPM)?

Accepted Answer

Paired serum and CSF antibody testing to demonstrate intrathecal antibody production.

Answer

Serum antibody testing for Sarcocystis neurona.

Answer

Western blot analysis of cerebrospinal fluid (CSF) alone.

Answer

Response to a course of antiprotozoal treatment.

Question 2

A veterinarian is performing a lameness examination on a horse with a right forelimb lameness. The lameness is completely resolved after a palmar digital nerve (PDN) block. Which of the following structures is LEAST likely to be the source of pain?

Accepted Answer

Proximal interphalangeal (pastern) joint

Answer

Navicular bone

Answer

Distal interphalangeal (coffin) joint

Answer

Digital cushion and sole

Question 3

A 2-year-old Thoroughbred colt presents with symmetric hindlimb ataxia that is worse when the horse's head is elevated. The colt is bright and alert with a normal appetite. Radiographs of the cervical spine reveal narrowing of the vertebral canal at C3-C4. What is the most likely diagnosis?

Accepted Answer

Cervical Vertebral Stenotic Myelopathy (CVSM)

Answer

Equine Motor Neuron Disease (EMND)

Answer

Equine Protozoal Myeloencephalitis (EPM)

Answer

Tetanus

Question 4

Which of the following clinical signs is most characteristic of stringhalt in a horse?

Accepted Answer

Involuntary, spasmodic hyperflexion of one or both hindlimbs during the walk.

Answer

Difficulty backing up with hindlimb hyperextension.

Answer

Symmetric hindlimb weakness and proprioceptive deficits.

Answer

Progressive, symmetric muscle atrophy of the back and hindquarters.

Question 5

A 5-year-old Warmblood gelding used for dressage is presented for poor performance and a subtle right hindlimb lameness. The lameness is not obvious on a straight line but is exacerbated when the horse is lunged on a hard surface with the affected limb to the inside. A low four-point nerve block fails to improve the lameness, but a subsequent tibial and peroneal nerve block significantly improves the gait. Pain is most likely originating from which region?

Accepted Answer

The hock (tarsus) or structures distal to it

Answer

The foot

Answer

The fetlock

Answer

The proximal suspensory ligament/proximal cannon bone region

Question 6

A veterinarian is presented with a horse exhibiting sudden, severe, non-weight-bearing lameness of the left forelimb. The digital pulses are bounding, and the horse is reluctant to move. There is a focal area of sensitivity to hoof testers over the sole. Which of the following is the most common cause for these acute and severe signs?

Accepted Answer

A subsolar abscess

Answer

Laminitis

Answer

Navicular syndrome

Answer

Osteoarthritis of the coffin joint