Lameness and Orthopaedic Disease SBAs

Question 1

Scenario: During a static examination of a horse’s forelimb, you are palpating the tendons and ligaments in the palmar aspect of the metacarpal region.

Lead-in: Which of the following structures is located most superficially in this region?

Options:

a) Deep digital flexor tendon (DDFT)
b) Suspensory ligament / 3rd interosseous muscle (TIOM)
c) Accessory ligament of the deep digital flexor tendon (ALDDFT)
d) Superficial digital flexor tendon (SDFT)
e) Palmar metacarpal nerve

Answer 1

Answer: d) Superficial digital flexor tendon (SDFT)

Explanation: In the palmar aspect of the metacarpal region, the superficial digital flexor tendon (SDFT) is the most superficial of the listed tendinous structures.

Question 2

Scenario: You are planning to perform diagnostic anaesthesia on a horse with forelimb lameness.

Lead-in: What is the general principle to follow when performing nerve blocks to localise the source of lameness?

Options:

a) Start proximally and work distally.
b) Block all four nerves at the level of the metacarpus initially.
c) Start distally and work proximally.
d) Use the highest concentration of local anaesthetic to ensure complete desensitisation.
e) Perform nerve blocks only after observing the horse during dynamic exercise.

Answer 2

Answer: c) Start distally and work proximally.

Explanation: The principle of diagnostic anaesthesia in the equine limb is to start with the most distal nerve block (palmar digital) and progressively block more proximal areas until the lameness resolves.

Question 3

Scenario: You are preparing to perform a series of nerve blocks on a horse with a subtle forelimb lameness.

Lead-in: Which local anaesthetic is most commonly used for diagnostic nerve blocks in the horse due to causing the least tissue reaction?

Options:

a) Lignocaine
b) Procaine
c) Mepivacaine
d) Bupivacaine
e) Ropivacaine

Answer 3

Answer: c) Mepivacaine

Explanation: Mepivacaine is the local anaesthetic most commonly used for nerve blocks in horses as it causes the least amount of tissue reaction.

Question 4

Scenario: A horse with forelimb lameness shows improvement but not complete resolution after a palmar digital nerve block. The lameness resolves completely after an abaxial sesamoid nerve block.

Lead-in: Based on these findings, where is the most likely primary source of the lameness?

Options:

a) Structures within the foot only.
b) Structures in the foot and pastern.
c) Structures in the pastern and palmar fetlock.
d) Structures in the metacarpal region.
e) Structures proximal to the fetlock.

Answer 4

Answer: c) Structures in the pastern and palmar fetlock.

Explanation: The palmar digital nerve block desensitises the foot. Improvement with this block suggests involvement of the foot. Complete resolution with the abaxial sesamoid nerve block, which desensitises the foot, pastern, and palmar fetlock, indicates the primary source of lameness is likely located in the pastern or palmar fetlock region.

Question 5

Identify the structures on this distal limb ultrasound.

Answer 5

A - SDFT
B - DDFT
C - Straight distal sesamoidean ligament.
D - Oblique distal sesamoidean ligament.

Question 6

You have been asked to re-examine a horse which has previously had proximal
interphalangeal (pastern) joint pain which resolved, and the horse has now gone
lame again. What response to nerve blocks would you expect if the proximal
interphalangeal joint was still painful?

A. The lameness would completely resolve with a palmar digital nerve block
▪ B. The lameness would improve with a palmar digital nerve block and
completely resolve with an abaxial sesamoid nerve block.
▪ C. The lameness would improve with an abaxial sesamoid nerve block and
completely resolve with a low 4 point nerve block.
▪ D. The lameness would improve with a a low 4 point nerve block and completely
resolve with a high 4 point nerve block.

Answer 6

B

Question 7

Scenario: During the palpation phase of a hindlimb static examination, you are assessing the hock region.

Lead-in: Where is the tibio-tarsal joint effusion best palpated?

Options:

a) On the dorsal aspect of the hock.
b) On the lateral aspect, proximal to the calcaneus.
c) On the medial aspect, between the tibia and talus bones.
d) On the plantar aspect, distal to the sustentaculum tali.
e) On the cranial aspect, over the central tarsal bone.

Answer 7

Answer: c) On the medial aspect, between the tibia and talus bones.

Explanation: Effusion in the tibio-tarsal joint of the hock is best palpated medially, between the tibia and talus bones.

Question 8

Scenario: You have performed a plantar digital nerve block on a horse with hindlimb lameness, resulting in only slight improvement. You then perform an abaxial sesamoid nerve block.

Lead-in: Which anatomical area is additionally desensitised by the abaxial sesamoid nerve block compared to the plantar digital nerve block?

Options:

a) The stifle joint.
b) The hock joint.
c) The metatarsal region.
d) The pastern and palmar fetlock.
e) The muscles of the gaskin.

Answer 8

Answer: d) The pastern and palmar fetlock.

Explanation: The plantar digital nerve block primarily desensitises the foot. The abaxial sesamoid nerve block desensitises the foot, pastern, and palmar fetlock region.

Question 9

Scenario: You are considering performing a low four-point nerve block on a horse with hindlimb lameness.

Lead-in: Which nerves are targeted in this block?

Options:

a) Tibial and peroneal nerves at the level of the hock.
b) Medial and lateral plantar nerves and medial and lateral plantar metatarsal nerves in the distal metatarsus.
c) Medial and lateral plantar digital nerves at the level of the pastern.
d) Deep and superficial branches of the peroneal nerve at the level of the stifle.
e) Branches of the sciatic nerve proximal to the hock.

Answer 9

Answer: b) Medial and lateral plantar nerves and medial and lateral plantar metatarsal nerves in the distal metatarsus.

Explanation: The low four-point nerve block in the hindlimb targets the medial and lateral plantar nerves and the medial and lateral plantar metatarsal nerves in the distal metatarsus, desensitising the fetlock and below.

Question 10

Scenario: You suspect a horse has pain originating from the proximal suspensory ligament of the hindlimb.

Lead-in: Which perineural nerve block is most specific for localising pain to this structure?

Options:

a) Plantar digital nerve block.
b) Abaxial sesamoid nerve block.
c) Low four-point block.
d) Tibial and peroneal nerve blocks.
e) Deep branch of the lateral plantar nerve block.

Answer 10

Answer: e) Deep branch of the lateral plantar nerve block.

Explanation: The deep branch of the lateral plantar nerve (DBLPN) block is considered a fairly specific block for the proximal suspensory ligament in the hindlimb.

Question 11

Scenario: You are performing perineural anaesthesia of the hindlimb.

Lead-in: What is a crucial safety consideration for both the practitioner and the horse during these procedures?

Options:

a) Avoiding sedation to allow accurate assessment of lameness.
b) Ensuring the horse is weight-bearing on the limb being blocked.
c) Adequate restraint of the patient by a capable handler.
d) Using a small gauge needle to minimise tissue reaction.
e) Applying a distal limb bandage immediately after each block.

Answer 11

Answer: c) Adequate restraint of the patient by a capable handler.

Explanation: Diagnostic anaesthesia on the hindlimb is considered a potentially dangerous procedure, and adequate restraint of the patient with a capable handler is very important for the safety of everyone involved.

Question 12

Scenario: You are performing a dynamic lameness examination of a horse. You observe a distinct head nod when the horse trots in a straight line.

Lead-in: According to the typical signs of lameness, which limb is most likely affected?

Options:

a) The left hindlimb
b) The right hindlimb
c) The left forelimb
d) The right forelimb
e) Either hindlimb

Answer 12

Answer: d) The right forelimb

Explanation: A head nod, where the horse’s head goes down when the sound limb strikes the ground, is a classic sign of forelimb lameness. The head nods down when the sound forelimb bears weight; therefore, the opposite forelimb (the right forelimb in this case) is the lame limb.

Question 13

Scenario: During a dynamic lameness exam, you observe the horse trotting away from you. You notice an increased vertical movement of the tuber coxae on the right hindlimb compared to the left.

Lead-in: Which hindlimb is most likely lame?

Options:

a) The left hindlimb
b) The right hindlimb
c) Both hindlimbs equally
d) It is impossible to tell from this sign.
e) This sign indicates forelimb lameness.

Answer 13

Answer: b) The right hindlimb

Explanation: In hindlimb lameness, the lame limb will often have a greater vertical movement of the tuber coxae during the trot.

Question 14

Scenario: A horse presents with acute onset, severe lameness (AAEP grade 4/5) in the left forelimb after being kicked in the stable. There is heat and swelling over the mid-metacarpal region.

Lead-in: According to the triage of acute musculoskeletal injuries, what is the priority level for this case?

Options:

a) Priority 1: Immediate action
b) Priority 2: Do not move
c) Priority 3: Requires urgent attention
d) Priority 4: Delayed action
e) Not an emergency

Answer 14

Answer: c) Priority 3: Requires urgent attention

Explanation: Acute onset severe lameness with heat and swelling after trauma suggests a significant injury, potentially a fracture. Cases with synovial or bony involvement or contaminated wounds are classified as Priority 3, requiring urgent attention.

Question 15

Scenario: A horse with a suspected fracture of the radius is being prepared for transport to a referral hospital.

Lead-in: According to the principles of first aid for fractures in the horse, where should a splint be placed to best stabilise this injury?

Options:

a) Dorsally from the hoof to the carpus.
b) Laterally from the hoof to the elbow.
c) Medially from the hoof to the carpus.
d) Plantarly from the hoof to the stifle.
e) Caudally from the hoof to the hock.

Answer 15

Answer: b) Laterally from the hoof to the elbow.

Explanation: For fractures of the radius (Region 3), a splint should be placed laterally (and sometimes medially) extending from the hoof up to the elbow to provide adequate stabilisation.

Question 16

Scenario: A racehorse pulls up acutely lame during training. After five days of box rest, the lameness improves from 5/10 to 1/10. Palpation reveals no specific localising signs.

Lead-in: According to the diagnostic approach to fractures, which diagnostic test is most likely to identify a non-displaced stress fracture in this case?

Options:

a) Radiography
b) Ultrasound
c) Nerve blocks
d) Gamma scintigraphy
e) Computed tomography

Answer 16

Answer: d) Gamma scintigraphy

Explanation: Gamma scintigraphy is valuable for identifying non-displaced stress fractures, especially in areas that are difficult to image with radiography, such as the tibia or radius.

Question 17

Scenario: A horse has a small, unstable articular fragment in the proximal interphalangeal joint.

Lead-in: According to the principles of fracture management, what is the recommended treatment for this type of fragment?

Options:

a) Conservative management with box rest.
b) External coaptation with a cast.
c) Removal of the fragment.
d) Stabilisation with lag screws.
e) Intra-articular injection of corticosteroids.

Answer 17

Answer: c) Removal of the fragment.

Explanation: For small, unstable articular fragments that are not an integral part of the articular surface, the principle of fracture management is to remove them as they can cause trauma if left in place

Question 18

Scenario: A horse with a wound over the plantar fetlock region has radiographs showing multiple small fractures of the sesamoid bones.

Lead-in: According to the information on fracture complications, injury to which soft tissue structure in this region would most significantly impact the prognosis?

Options:

a) Digital extensor tendon
b) Superficial digital flexor tendon
c) Deep digital flexor tendon
d) Suspensory ligament
e) Plantar annular ligament

Answer 18

Answer: d) Suspensory ligament

Explanation: Injury to the suspensory ligament, which runs over the plantar aspect of the fetlock, along with fractures of the sesamoid bones, can significantly impact the prognosis for return to athletic function.

Question 19

Scenario: You are called to a horse that has sustained an open, comminuted fracture of the tibia. The horse is over 500 kg.

Lead-in: According to the guidelines on when to consider euthanasia for fractures, what is the prognosis for this horse?

Options:

a) Good with appropriate surgical repair.
b) Fair with external fixation.
c) Guarded but potentially manageable with internal fixation.
d) Poor, and euthanasia should be considered.
e) Dependent on the owner’s financial resources.

Answer 19

Answer: d) Poor, and euthanasia should be considered.

Explanation: Open comminuted long bone fractures, including complete fractures of the tibia in horses over 500 kg, carry a poor prognosis for repair and are often considered irreparable, leading to a recommendation for euthanasia.

Question 20

Scenario: A horse with chronic lameness localised to the distal limb shows improvement with a palmar digital nerve block but not complete resolution. The lameness resolves completely with an abaxial sesamoid nerve block.

Lead-in: Where is the most likely source of pain?

Options:

a) Sole of the foot.
b) Digital cushion.
c) Navicular bursa.
d) Pastern joint.
e) Deep digital flexor tendon within the foot.

Answer 20

Answer: d) Pastern joint.

Explanation: The palmar digital nerve block desensitises the palmar aspect of the foot. The abaxial sesamoid nerve block desensitises the foot, pastern, and palmar fetlock. Improvement with the palmar digital block suggests pain in the foot, but complete resolution with the abaxial sesamoid block indicates the pain is likely originating in the pastern or palmar fetlock region, which is additionally desensitised by the latter block.

Question 21

Scenario: You are performing a lameness examination and observe a horse with a subtle, inconsistent forelimb lameness. You decide to perform flexion tests.

Lead-in: How long should you typically hold a flexion test on a limb before trotting the horse off?

Options:

a) 10-20 seconds
b) 30-60 seconds
c) 1-2 minutes
d) 3-5 minutes
e) Until the horse shows signs of discomfort.

Answer 21

Answer: b) 30-60 seconds

Explanation: Flexion tests are typically held for 30-60 seconds before the horse is trotted off to assess for any exacerbation of lameness, which can help localise the area of pain.

Question 22

Scenario: A horse presents with acute, severe lameness in a hindlimb. You are concerned about a potential fracture.

Lead-in: According to the guidelines on when to avoid nerve blocks, why should you refrain from performing nerve blocks in this situation?

Options:

a) Nerve blocks are ineffective for severe lameness.
b) Nerve blocks may mask the pain and allow the horse to bear weight, potentially worsening a fracture.
c) Nerve blocks can interfere with radiographic interpretation.
d) The horse is likely too painful to allow nerve blocks to be performed safely.
e) Nerve blocks are only useful for chronic lameness.

Answer 22

Answer: b) Nerve blocks may mask the pain and allow the horse to bear weight, potentially worsening a fracture.

Explanation: Nerve blocks should be avoided in cases of suspected fractures or severe soft tissue injuries because removing the pain could allow the horse to bear weight on the injured limb, leading to catastrophic consequences or further damage.

Question 23

Scenario: You are assessing a horse with lameness and observe a bounding digital pulse in the left forelimb.

Lead-in: While this can be associated with various conditions, what specific finding on further examination would make you highly suspicious of a pedal bone fracture?

Options:

a) Swelling extending up the limb to the carpus.
b) Pain elicited on palpation of the shoulder.
c) Heat and pain localised to the hoof.
d) Reluctance to flex the elbow.
e) Increased movement of the fetlock.

Answer 23

Answer: c) Heat and pain localised to the hoof.

Explanation: A bounding digital pulse, along with heat and pain localised to the hoof, is a clinical finding that would make you suspicious of a pedal bone fracture.

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Question 24

Scenario: You are called to a stable yard to examine a horse with acute, severe lameness in the left forelimb. The owner reports the horse was sound yesterday. On examination, the horse is unwilling to bear weight on the limb, and there is a visible deformity.

Lead-in: What is the most likely underlying cause of this presentation?

Options:

a) Superficial digital flexor tendon rupture
b) Deep digital flexor tendon rupture
c) Complete long bone fracture
d) Subsolar abscess
e) Suspensory ligament desmitis

Answer 24

Answer: c) Complete long bone fracture

Explanation: Acute onset, severe lameness with inability to bear weight and visible deformity strongly suggests a complete long bone fracture.

Question 25

Scenario: A horse with a suspected fracture of the distal radius is being prepared for transport. Lead-in: Following the principles of first aid for fractures, where should a splint ideally extend to provide adequate stabilisation? Options: a) From the hoof to the carpus b) From the hoof to the elbow c) From the hoof to the shoulder d) From the hoof to the proximal metacarpus e) Only to the mid-metacarpal region

Answer 25

Answer: b) From the hoof to the elbow Explanation: For fractures of the radius (Region 3), a splint should be placed laterally (and sometimes medially) extending from the hoof up to the elbow to provide adequate stabilisation.

Question 26

Scenario: A racehorse presents with acute onset lameness after exercise. Radiographs are unremarkable. You suspect a stress fracture. Lead-in: Which advanced imaging modality is most sensitive for detecting non-displaced stress fractures in equine long bones? Options: a) Ultrasound b) Computed tomography (CT) c) Magnetic resonance imaging (MRI) d) Gamma scintigraphy e) Positron emission tomography (PET)

Answer 26

Answer: d) Gamma scintigraphy Explanation: Gamma scintigraphy is highly sensitive for detecting areas of increased bone turnover associated with stress fractures, even when radiographs are normal.

Question 27

Scenario: A horse with a chronic, low-grade lameness that improves with distal limb flexion. You perform ultrasound of the palmar metacarpal region and identify a core lesion within the superficial digital flexor tendon (SDFT). Lead-in: What is the most likely location of this lesion? Options: a) Within the digital flexor tendon sheath b) At the level of the pastern c) In the mid-metacarpal region d) At the insertion onto the second phalanx e) At the origin proximal to the carpus

Answer 27

Answer: c) In the mid-metacarpal region Explanation: The vast majority of SDFT injuries and pathology occur in the mid-metacarpal region of the forelimb.

Question 28

Scenario: A horse is diagnosed with acute superficial digital flexor tendonitis. Lead-in: What is an important initial treatment? Options: a) Application of heat packs b) Controlled exercise c) Intralesional steroid injection d) Cold therapy e) Prolonged rest without support

Answer 28

Answer: d) Cold therapy Explanation: Cold therapy (e.g., ice or cold hosing) is recommended in the inflammatory phase of tendon injuries to help reduce inflammation and swelling.

Question 29

Scenario: A horse with a confirmed SDFT core lesion is 3 weeks into rehabilitation and is sound at walk. Ultrasound reveals a persistent lesion. Lead-in: Which of the following intralesional therapies might be considered at this stage to improve healing? Options: a) Extracorporeal shockwave therapy (ESWT) b) High-power laser therapy c) Stem cell therapy d) Intralesional corticosteroid injection e) Systemic non-steroidal anti-inflammatory drugs (NSAIDs) only

Answer 29

Answer: c) Stem cell therapy Explanation: Intralesional therapies like stem cell therapy are often considered at the start of the repair phase (2-3 weeks after injury) to potentially improve the speed and quality of healing when a core lesion is present.

Question 30

Scenario: A horse has been diagnosed with proximal suspensory ligament desmitis. Lead-in: When is it generally appropriate to commence controlled exercise? Options: a) Immediately after diagnosis b) Once the horse is completely sound c) At the end of the inflammatory phase (roughly 2-4 weeks) d) After 6 months of box rest e) Only after ultrasound reveals complete resolution of the lesion

Answer 30

Answer: c) At the end of the inflammatory phase (roughly 2-4 weeks) Explanation: More modern approaches to soft tissue injury rehabilitation involve commencing controlled exercise at the end of the inflammatory phase (roughly 2-4 weeks), based on clinical parameters.

Question 31

Scenario: A horse with a soft tissue injury is undergoing rehabilitation. Lead-in: What is a key aspect to monitor when increasing exercise intensity? Options: a) Heart rate response only b) Respiratory rate only c) Lameness, palpation findings, and ultrasound appearance d) Body temperature e) Appetite and water intake

Answer 31

Answer: c) Lameness, palpation findings, and ultrasound appearance Explanation: When increasing exercise intensity during rehabilitation, it is important to monitor lameness, palpation findings (heat, pain, swelling), and ultrasound appearance of the lesion to guide progression.

Question 32

Scenario: A horse has sustained an overreach injury resulting in an acute superficial digital flexor tendon tear. Lead-in: Is this considered a true acute traumatic incident or the culmination of microdamage? Options: a) Always the culmination of microdamage b) Always a true acute traumatic incident c) Can be either, depending on the severity d) More likely the culmination of microdamage in racehorses e) More likely a true acute traumatic incident in young horses

Answer 32

Answer: b) Always a true acute traumatic incident Explanation: Overreach or interference injuries, where a loaded forelimb is struck by a rapidly protracting hindlimb, are considered true acute traumatic incidents that can cause acute damage to previously normal soft tissues.

Question 33

Scenario: You are performing emergency field radiography on a horse with a severely painful foot. You obtain a dorsopalmar view. Lead-in: Which fracture is most common in the equine pedal bone? Options: a) Sagittal fracture b) Transverse fracture c) Comminuted fracture d) Chip fracture of the extensor process e) Articular wing fracture

Answer 33

Answer: b) Transverse fracture Explanation: Transverse fractures of the pedal bone are very common in horses experiencing severe foot pain.

Question 34

Scenario: A horse has a fracture of the proximal phalanx ("split pastern"). Lead-in: What type of fracture configuration is this? Options: a) Transverse b) Oblique c) Spiral d) Sagittal e) Comminuted

Answer 34

Answer: d) Sagittal Explanation: A "split pastern" fracture is a sagittal fracture of the first phalanx (P1).

Question 35

Scenario: A horse has sustained a direct trauma to the lateral aspect of the metacarpus. Radiography reveals a fracture of the lateral splint bone (fourth metacarpal). Lead-in: What is the typical mechanism of injury for a splint bone fracture? Options: a) Repetitive stress b) Excessive loading during exercise c) Direct trauma d) Sudden twisting of the limb e) Overextension of the fetlock

Answer 35

Answer: c) Direct trauma Explanation: Splint bone fractures are most commonly the result of direct trauma, such as a kick.

Question 36

Scenario: A horse is diagnosed with a third carpal bone slab fracture. Lead-in: What term describes fractures that involve more than one articular surface, as seen in slab fractures? Options: a) Simple b) Comminuted c) Incomplete d) Bi-articulate e) Avulsion

Answer 36

Answer: d) Bi-articulate Explanation: Fractures that cross and involve more than one articular surface are known as bi-articulate fractures, and third carpal bone slab fractures are an example of this.

Question 37

Scenario: A horse has sustained an olecranon fracture. Lead-in: Which muscle group's pull necessitates internal fixation for most olecranon fractures to achieve a good prognosis? Options: a) Digital flexors b) Digital extensors c) Carpal flexors d) Carpal extensors e) Triceps

Answer 37

Answer: e) Triceps Explanation: The pull of the triceps muscle group on the olecranon makes internal fixation the recommended treatment for most olecranon fractures to counteract this force and achieve a good prognosis.

Question 38

Scenario: A horse with a suspected severe soft tissue injury to the flexor tendons is presented for ultrasound examination. Lead-in: In cases where severe soft tissue injury is suspected, what should be considered before performing nerve blocks? Options: a) Performing radiography first b) Clipping the entire limb c) Scanning the limb with ultrasound d) Administering systemic antibiotics e) Applying a distal limb bandage

Answer 38

Answer: c) Scanning the limb with ultrasound Explanation: It is advisable to consider scanning the limb with ultrasound before performing nerve blocks in cases where severe soft tissue injury is suspected to avoid masking pain that might be crucial for diagnosis.

Question 39

Scenario: You are performing ultrasound on a horse with chronic forelimb lameness. You identify an enlarged superficial digital flexor tendon with reduced echogenicity. Lead-in: What does reduced echogenicity (darker appearance) typically indicate in a tendon? Options: a) Increased collagen type I b) Increased collagen type III c) Mineralisation d) Increased glycosaminoglycans (GAGs) e) Normal tendon tissue

Answer 39

Answer: b) Increased collagen type III Explanation: In the reparative phase of tendon healing, there is an increase in collagen type III, which has a smaller fibril size and appears hypoechoic (darker) on ultrasound compared to the more organised collagen type I found in healthy tendon.

Question 40

Scenario: A horse is diagnosed with tendonitis of the superficial digital flexor tendon. The owner asks about the long-term outcome. Lead-in: What is a common long-term consequence affecting fetlock extension in horses with SDFT injuries? Options: a) Increased fetlock extension b) Reduced fetlock extension c) No change in fetlock extension d) Intermittent fetlock hyperextension e) Development of carpal contracture

Answer 40

Answer: b) Reduced fetlock extension Explanation: During the remodelling phase of SDFT healing, the tendon may become less pliable, leading to reduced fetlock extension.

Question 41

Scenario: A horse with a suspected fracture is being transported to a referral hospital. Lead-in: What is important to do regarding open wounds associated with the fracture? Options: a) Apply a tight bandage to stop bleeding. b) Lavage the wound thoroughly with antiseptic solution. c) Cover and protect any open wounds. d) Apply topical antibiotics liberally. e) Attempt to close the wound with sutures in the field.

Answer 41

Answer: c) Cover and protect any open wounds. Explanation: In cases of open fractures, it is important to cover and protect any wounds to minimise contamination until definitive surgical treatment can be performed.

Question 42

Scenario: A horse has been treated for a soft tissue injury and is undergoing rehabilitation. The owner is keen to turn the horse out to pasture. Lead-in: What is a significant risk associated with turning a horse out to pasture too early? Options: a) Development of laminitis in the contralateral limb. b) Increased risk of colic due to grass intake. c) High risk of re-injury due to uncontrolled exercise. d) Decreased bone density due to reduced loading. e) Development of behavioural vices.

Answer 42

Answer: c) High risk of re-injury due to uncontrolled exercise. Explanation: Turning a horse out to pasture allows for uncontrolled exercise, which comes with a high risk of re-injuring healing soft tissues. Controlled exercise programs are preferred during rehabilitation.

Question 43

Scenario: A horse with chronic osteoarthritis of the pastern joint is being managed with intra-articular corticosteroids. The owner is asking about other long-term pain management options during rehabilitation. Lead-in: Which of the following long-term analgesic options is mentioned in the rehabilitation lecture? Options: a) Intravenous bisphosphonates b) Oral corticosteroids c) Intra-articular hyaluronic acid d) Oral phenylbutazone e) Neurectomy

Answer 43

Answer: d) Oral phenylbutazone Explanation: Oral phenylbutazone is mentioned as a commonly used NSAID for long-term analgesia in horses during rehabilitation, although the owner should be warned about potential complications.

Question 44

Scenario: A 6-year-old Thoroughbred mare presents with a history of recurrent episodes of stiffness, sweating, and reluctance to move after light exercise. Lead-in: Which of the following is the most likely underlying cause of these signs? Options: a) Hyperkalaemic periodic paralysis (HYPP) b) Polysaccharide storage myopathy type 1 (PSSM1) c) Recurrent exertional rhabdomyolysis (RER) d) Ionophore toxicity e) Malignant hyperthermia (MH)

Answer 44

Answer: c) Recurrent exertional rhabdomyolysis (RER) Explanation: Recurrent exertional rhabdomyolysis (RER) is a common cause of exercise intolerance and muscle pain in Thoroughbreds, often triggered by excitement or light exercise.

Question 45

Scenario: A Quarter Horse presents with episodes of muscle fasciculations, weakness, and recumbency. The owner reports the horse's sire was known to have a similar condition. Lead-in: Which of the following genetic muscle disorders is most likely in this horse? Options: a) Polysaccharide storage myopathy type 2 (PSSM2) b) Immune-mediated myositis (IMM) c) Exertional rhabdomyolysis (ER) d) Hyperkalaemic periodic paralysis (HYPP) e) Myofibrillar myopathy (MFM)

Answer 45

Answer: d) Hyperkalaemic periodic paralysis (HYPP) Explanation: Hyperkalaemic periodic paralysis (HYPP) is a genetic sodium channelopathy common in Quarter Horses and related breeds, characterised by episodes of muscle fasciculations, weakness, and sometimes recumbency, often triggered by changes in diet or stress.

Question 46

Scenario: A horse is presented with acute, severe muscle stiffness, pain, and dark urine after strenuous exercise. Lead-in: What is the most appropriate initial diagnostic test to assess the severity of muscle damage? Options: a) Complete blood count (CBC) b) Serum biochemistry panel including creatine kinase (CK) and aspartate aminotransferase (AST) c) Urinalysis for glucose d) Faecal egg count e) Arterial blood gas analysis

Answer 46

Answer: b) Serum biochemistry panel including creatine kinase (CK) and aspartate aminotransferase (AST) Explanation: Creatine kinase (CK) and aspartate aminotransferase (AST) are muscle-specific enzymes that are released into the bloodstream when muscle cells are damaged. Elevated levels indicate the severity of muscle damage.

Question 47

Scenario: A horse with suspected polysaccharide storage myopathy type 1 (PSSM1) has a muscle biopsy performed. Lead-in: What is the characteristic finding on histopathology that supports this diagnosis? Options: a) Inflammation and muscle fibre necrosis b) Accumulation of glycogen that is resistant to amylase digestion c) Presence of abnormal myofibrils d) Increased number of centrally located nuclei in muscle fibres e) Deposition of amyloid protein within muscle tissue

Answer 47

Answer: b) Accumulation of glycogen that is resistant to amylase digestion Explanation: PSSM1 is characterised by an abnormal accumulation of glycogen in skeletal muscle that is resistant to amylase digestion, which can be visualised on muscle biopsy.

Question 48

Scenario: A horse with exertional rhabdomyolysis has markedly elevated creatine kinase (CK) levels and is producing dark urine. Lead-in: What is the primary concern associated with myoglobinuria (dark urine) in these cases? Options: a) Development of anaemia b) Increased risk of colic c) Acute kidney injury d) Electrolyte imbalances leading to cardiac arrhythmias e) Liver failure

Answer 48

Answer: c) Acute kidney injury Explanation: Myoglobin, released from damaged muscle cells, can be nephrotoxic and lead to acute kidney injury if present in high concentrations in the urine.

Question 49

Scenario: A horse is diagnosed with polysaccharide storage myopathy type 2 (PSSM2). Lead-in: Which of the following dietary management strategies is typically recommended for this condition? Options: a) High-starch, low-fat diet b) Low-starch, high-fat diet c) High-protein, low-carbohydrate diet d) Strict restriction of pasture access e) Supplementation with high levels of selenium and vitamin E

Answer 49

Answer: b) Low-starch, high-fat diet Explanation: PSSM2 management often involves a diet low in starch and non-structural carbohydrates, with fat added as an alternative energy source.

Question 50

Scenario: A horse with recurrent exertional rhabdomyolysis (RER) is being managed. Lead-in: Which of the following management strategies is crucial for preventing episodes of RER? Options: a) Sporadic turnout and exercise b) High-grain diet with limited forage c) Consistent daily exercise and turnout d) Infrequent grooming to avoid stress e) Supplementation with high doses of vitamin C

Answer 50

Answer: c) Consistent daily exercise and turnout Explanation: Consistent daily exercise and turnout help to improve muscle adaptation and reduce the likelihood of RER episodes. Inconsistent exercise patterns can trigger tying-up.

Question 51

Scenario: You inject a horse with procaine benzylpenicillin 2 days ago for localised pyoderma. You are called out as the horse now presents with acute onset muscle swelling and pain Lead-in: What is the most likely cause of this localised myopathy? Options: a) Exertional rhabdomyolysis b) Immune-mediated myositis c) Injection site reaction/focal myositis d) Malignant hyperthermia e) Nutritional myopathy

Answer 51

Answer: c) Injection site reaction/focal myositis Explanation: Localised muscle swelling and pain following an intramuscular injection are consistent with an injection site reaction or focal myositis, which can occur due to muscle trauma or irritation from the injected substance.

Question 52

Scenario: A horse is diagnosed with immune-mediated myositis (IMM). Lead-in: What is the recommended first-line treatment for IMM? Options: a) Non-steroidal anti-inflammatory drugs (NSAIDs) b) Corticosteroids c) Muscle relaxants d) Vitamin E and selenium supplementation e) Intravenous fluids only

Answer 52

Answer: b) Corticosteroids Explanation: Corticosteroids are the mainstay of treatment for immune-mediated myositis in horses due to their anti-inflammatory and immunosuppressive effects.

Question 53

Scenario: A horse with a history of malignant hyperthermia (MH) requires general anaesthesia for a minor procedure. Lead-in: Which of the following anaesthetic agents should be avoided in this horse due to the risk of triggering an MH episode? Options: a) Propofol b) Ketamine c) Isoflurane d) Sevoflurane e) Mepivacaine

Answer 53

Answer: c) Isoflurane Explanation: Inhalational anaesthetics like isoflurane and halothane are known triggers for malignant hyperthermia in susceptible individuals.

Question 54

Scenario: A horse with suspected exertional rhabdomyolysis has a creatine kinase (CK) level of 10,000 IU/L. Lead-in: What is an important aspect of initial treatment, besides pain management and anti-inflammatories, to prevent complications? Options: a) Strict box rest with no turnout b) Encouraging immediate return to light exercise c) Ensuring adequate hydration with intravenous fluids if necessary d) Supplementation with high levels of potassium e) Administration of muscle relaxants

Answer 54

Answer: c) Ensuring adequate hydration with intravenous fluids if necessary Explanation: Ensuring adequate hydration is crucial in cases of rhabdomyolysis to help flush myoglobin from the kidneys and prevent acute kidney injury.

Question 55

Scenario: A horse with immune-mediated myositis (IMM) shows muscle atrophy, particularly in the gluteal region. Lead-in: Which specific muscle protein is targeted by the immune system in some forms of IMM? Options: a) Actin b) Myosin heavy chain (MYH1) c) Troponin d) Creatine kinase e) Lactate dehydrogenase

Answer 55

Answer: b) Myosin heavy chain (MYH1) Explanation: Some forms of immune-mediated myositis target the myosin heavy chain (MYH1) protein in skeletal muscle, leading to muscle atrophy.

Question 55

Scenario: A horse with polysaccharide storage myopathy type 1 (PSSM1) is being managed with a low-starch, high-fat diet. Lead-in: Which of the following feeds should be significantly restricted in this horse's diet? Options: a) Soybean meal b) Alfalfa hay c) Oats d) Beet pulp e) Vegetable oil

Answer 55

Answer: c) Oats Explanation: Oats are a high-starch grain and should be significantly restricted in the diet of horses with PSSM1 to manage glycogen accumulation in the muscles.

Question 56

Scenario: A horse with a history of tying-up is being evaluated for the underlying cause. Genetic testing is performed. Lead-in: A positive result for the GYS1 mutation would indicate a predisposition to which muscle disorder? Options: a) Hyperkalaemic periodic paralysis (HYPP) b) Recurrent exertional rhabdomyolysis (RER) c) Polysaccharide storage myopathy type 1 (PSSM1) d) Malignant hyperthermia (MH) e) Myofibrillar myopathy (MFM)

Answer 56

Answer: c) Polysaccharide storage myopathy type 1 (PSSM1) Explanation: The GYS1 gene encodes for glycogen synthase, and a mutation in this gene is associated with Polysaccharide Storage Myopathy type 1 (PSSM1).

Question 57

Scenario: A horse with suspected non-exertional rhabdomyolysis has normal creatine kinase (CK) levels. Lead-in: Which of the following conditions is a potential cause of non-exertional rhabdomyolysis where CK levels may not be significantly elevated? Options: a) Polysaccharide storage myopathy type 1 (PSSM1) b) Recurrent exertional rhabdomyolysis (RER) c) Immune-mediated myositis (IMM) d) Nutritional myopathy (Vitamin E/Selenium deficiency) e) Malignant hyperthermia (MH)

Answer 57

Answer: d) Nutritional myopathy (Vitamin E/Selenium deficiency) Explanation: In nutritional myopathy, due to Vitamin E and/or selenium deficiency, muscle damage can occur without significant elevation of CK in some chronic cases.

Question 58

Scenario: A horse with hyperkalaemic periodic paralysis (HYPP) is experiencing an acute episode of muscle fasciculations and weakness. Lead-in: Which of the following treatments would be most appropriate to help lower serum potassium levels? Options: a) Intravenous calcium gluconate b) Oral potassium supplementation c) Intravenous dextrose and insulin d) Muscle relaxants e) Non-steroidal anti-inflammatory drugs (NSAIDs)

Answer 58

Answer: c) Intravenous dextrose and insulin Explanation: Dextrose and insulin help to drive potassium from the extracellular fluid back into the muscle cells, thus lowering serum potassium levels in horses with HYPP.

Question 59

Scenario: A horse with a history of recurrent tying-up is being managed with dietary changes. Lead-in: Besides reducing starch intake, what other dietary component is often beneficial for horses with exertional myopathies? Options: a) Increased protein b) Increased calcium c) Increased fat d) Decreased phosphorus e) Decreased magnesium

Answer 59

Answer: c) Increased fat Explanation: Increasing dietary fat can provide an alternative energy source for muscle work, reducing the reliance on glycogen and potentially decreasing the risk of exertional myopathies.

Question 60

Scenario: A horse with suspected immune-mediated myositis (IMM) shows a rapid response to corticosteroid treatment, but the owner is concerned about long-term steroid use. Lead-in: Which of the following steroid-sparing immunosuppressant drugs might be considered for long-term management of IMM? Options: a) Phenylbutazone b) Firocoxib c) Methotrexate d) Gabapentin e) Omeprazole

Answer 60

Answer: c) Methotrexate Explanation: Methotrexate is an immunosuppressant drug that can be used as a steroid-sparing agent in the long-term management of immune-mediated myositis in some horses.

Question 61

Scenario: A horse with myofibrillar myopathy (MFM) is being evaluated. Lead-in: Which of the following breeds has a recognised association with myofibrillar myopathy? Options: a) Thoroughbred b) Standardbred c) Arabian d) Warmblood e) Draft horse

Answer 61

Answer: d) Warmblood Explanation: Myofibrillar myopathy (MFM) has been recognised in Warmblood horses and is characterised by specific histological findings on muscle biopsy.

Question 62

Scenario: A horse with a history of exertional rhabdomyolysis is being prepared for transport after a mild episode. Lead-in: What is an important consideration regarding transport for these horses? Options: a) Ensuring the horse travels without a headcollar to reduce stress. b) Providing a high-grain meal immediately before transport. c) Avoiding transport if possible until muscle enzyme levels have returned to normal. d) Administering a sedative to keep the horse calm during transport. e) Transporting the horse in a fully enclosed trailer with limited ventilation.

Answer 62

Answer: c) Avoiding transport if possible until muscle enzyme levels have returned to normal. Explanation: Transport can be stressful and may exacerbate muscle damage in horses recovering from exertional rhabdomyolysis. It is generally recommended to avoid transport until muscle enzyme levels have returned to normal.

Question 63

You suspect a myopathy and submit a biopsy for histopathology. Based on the below slide, what is the diagnosis?

Answer 63

PSSM Periodic acid Schiff (PAS) straining for PSSM * Amylase digestion first removes all normal accumulations of glycogen * Dark staining cells from affected horse denoting abnormal accumulations of resistant glycogen

Question 64

You suspect a myopathy and submit a biopsy for histopathology. Based on the below slide, what is the diagnosis?

Answer 64

Myofibrillar myopathy Desmin stain for myofibrillar myopathy * Abnormal accumulations of desmin in an affected horse

Question 65

You suspect a myopathy and submit a biopsy for histopathology. Based on the below slide, what is the diagnosis?

Answer 65

Recurrent Equine Rhabdomyolysis Haematoxylin and eosin (H&E) staining suggestive of RER * Internalised nuclei (should be peripheral), marked variation in fiber sizes, infiltration of macrophages (black arrow) * Caffeine sensitivity is also a feature – performed on fresh samples

Question 66

Scenario: You are presented with a horse that sustained a laceration to its lower limb 6 hours ago. The wound is bleeding moderately. what is the first priority in managing this wound? Options: a) Apply a topical antiseptic. b) Achieve haemostasis. c) Lavage the wound with sterile saline. d) Apply a pressure bandage. e) Assess the horse's tetanus vaccination status.

Answer 66

Answer: b) Achieve haemostasis. Explanation: The immediate priority in any bleeding wound is to control the haemorrhage. This can often be achieved with direct pressure.

Question 67

Scenario: You are evaluating a wound on a horse's leg near the carpus. You are concerned about potential involvement of the carpal joint. Lead-in: Which of the following landmarks would indicate potential synovial sepsis of the carpal joint if the wound overlies it? Options: a) The accessory carpal bone. b) The chestnut. c) The ergot. d) The point of the hock. e) The lateral digital extensor tendon.

Answer 67

Answer: a) The accessory carpal bone. Explanation: A wound overlying the accessory carpal bone in the forelimb distal limb is in close proximity to the carpal joint and raises suspicion for synovial sepsis.

Question 68

Scenario: You are preparing to lavage a wound on a horse's distal limb. Lead-in: Which of the following solutions is most appropriate for initial wound lavage? Options: a) Povidone-iodine scrub b) Chlorhexidine scrub c) Dilute chlorhexidine solution d) Hydrogen peroxide e) Strong iodine solution

Answer 68

Answer: c) Dilute chlorhexidine solution Explanation: Dilute chlorhexidine solution (0.05%) or sterile saline are appropriate for wound lavage. Scrub solutions and strong iodine or peroxide can be cytotoxic to healing tissues.

Question 69

Scenario: You are examining a puncture wound on a horse's foot. Lead-in: What is the most important initial step in evaluating this type of wound? Options: a) Apply a poultice. b) Explore the depth and direction of the wound. c) Administer systemic antibiotics. d) Radiograph the foot immediately. e) Soak the foot in Epsom salts.

Answer 69

Answer: b) Explore the depth and direction of the wound. Explanation: With puncture wounds, it is crucial to determine the extent of penetration and if any vital structures are involved. This often requires careful probing.

Question 70

Scenario: You are presented with a horse that has a full-thickness skin laceration with minimal contamination that is less than 6 hours old. Lead-in: Which method of wound closure is most appropriate for this wound? Options: a) Second intention healing b) Delayed primary closure c) Primary closure d) Contraction and epithelialisation e) Application of a skin graft

Answer 70

Answer: c) Primary closure Explanation: Primary closure is indicated for clean, fresh wounds (less than 6-8 hours old) where the edges can be easily apposed.

Question 71

Scenario: You are managing a chronic wound on a horse's lower limb that has developed excessive granulation tissue ("proud flesh"). Lead-in: What is the most effective method for managing this complication? Options: a) Applying topical corticosteroids b) Surgical debridement c) Bandaging with a non-adherent dressing d) Increasing the frequency of wound lavage e) Applying a hydrogel

Answer 71

Answer: b) Surgical debridement Explanation: Surgical removal of the excessive granulation tissue (proud flesh) is often necessary to allow the wound to heal properly.

Question 72

Scenario: You are treating a deep wound on a horse's limb that you suspect may become infected. Lead-in: What is a reason for placing a drain in a wound? Options: a) To increase blood flow to the wound. b) To deliver topical medications directly to the wound bed. c) To eliminate dead space and prevent build-up of exudate. d) To prevent the dressing from sticking to the wound. e) To provide structural support to the healing tissues.

Answer 72

Answer: c) To eliminate dead space and prevent build-up of exudate. Explanation: Drains are used to remove fluid and prevent the accumulation of exudate or serum in the wound, which can delay healing and promote infection.

Question 73

Scenario: You are debriding a heavily contaminated wound on a horse's leg. Lead-in: Which of the following is the most appropriate method for sharp debridement? Options: a) Using a scalpel blade to remove non-viable tissue. b) Applying a hypertonic saline dressing. c) Using enzymatic debriding agents. d) Allowing the wound to heal by second intention. e) Applying a dry-to-dry bandage.

Answer 73

Answer: a) Using a scalpel blade to remove non-viable tissue. Explanation: Sharp debridement involves the surgical removal of devitalized tissue with a scalpel blade, which is the most effective method for removing heavily contaminated or necrotic material.

Question 74

Scenario: A horse sustains a traumatic wound that penetrates the digital flexor tendon sheath. Lead-in: What is a significant concern associated with this type of wound? Options: a) Excessive granulation tissue formation. b) Delayed wound contraction. c) Septic tenosynovitis. d) Formation of a sarcoid. e) Development of proud flesh.

Answer 74

Answer: c) Septic tenosynovitis. Explanation: Penetration of a synovial structure like the digital flexor tendon sheath carries a high risk of developing a severe infection known as septic tenosynovitis, which requires aggressive treatment.

Question 75

Scenario: You are evaluating a horse with a chronic, non-healing wound. Radiographs show no evidence of foreign material or bone involvement. Lead-in: What should be considered as a potential underlying factor delaying wound healing? Options: a) Adequate blood supply to the wound bed. b) Presence of a healthy granulation tissue layer. c) Lack of wound contraction. d) Presence of a biofilm. e) Appropriate moisture balance in the wound.

Answer 75

Answer: d) Presence of a biofilm. Explanation: Biofilms are communities of bacteria encased in a protective matrix that can be resistant to antibiotics and impede wound healing.

Question 76

Scenario: You are treating a horse with a wound that is healing well by second intention. Lead-in: What is the final stage of wound healing characterised by? Options: a) Formation of a blood clot. b) Deposition of granulation tissue. c) Migration and proliferation of epithelial cells. d) Collagen synthesis and cross-linking. e) Contraction of the wound edges.

Answer 76

Answer: d) Collagen synthesis and cross-linking. Explanation: The remodelling phase is the final stage of wound healing, characterised by the reorganisation of collagen fibres, increased tensile strength, and maturation of the scar tissue through collagen synthesis and cross-linking.

Question 77

Scenario: You are asked to advise an owner on the care of a minor, clean laceration on their horse's limb. The horse's tetanus vaccination is up to date. Lead-in: What is the most important advice regarding wound cleaning for this type of wound in the first 24 hours? Options: a) Apply a strong antiseptic solution three times daily. b) Keep the wound covered with a tight bandage at all times. c) Gently flush the wound with clean, cold water. d) Apply topical corticosteroids to reduce inflammation. e) Leave the wound open to the air to dry out.

Answer 77

Answer: c) Gently flush the wound with clean, cold water. Explanation: For minor, clean wounds, gentle flushing with clean, cold water is often sufficient to remove debris and contaminants in the initial stages. Strong antiseptics can be harmful to healing tissues.

Question 78

Scenario: A horse presents with a subtle, chronic forelimb lameness that improves significantly but does not completely resolve with a palmar digital nerve block. Lead-in: Which anatomical structures are desensitised by a palmar digital nerve block? Options: a) The entire foot and pastern b) The palmar aspect of the foot, including the heel, sole, frog, and digital cushion c) The foot, pastern, and palmar fetlock d) The foot, pastern, fetlock, and metacarpal region e) Only the structures within the hoof capsule

Answer 78

Answer: b) The palmar aspect of the foot, including the heel, sole, frog, and digital cushion Explanation: A palmar digital nerve block primarily desensitises the palmar aspect of the foot, including the heel, sole, frog, and digital cushion, as well as the distal interphalangeal joint and digital portion of the deep digital flexor tendon.

Question 79

Scenario: A horse with chronic, low-grade forelimb lameness shows no localising signs on initial examination but blocks sound to a palmar digital nerve block. Lead-in: Which of the following conditions is a common cause of lameness that blocks to the foot with no other localising signs? Options: a) Proximal suspensory ligament desmitis b) Carpal osteoarthritis c) Navicular degeneration d) Shoulder osteoarthritis e) Radial fracture

Answer 79

Answer: c) Navicular degeneration Explanation: Navicular degeneration is a common cause of chronic, often bilateral, forelimb lameness that typically blocks to a palmar digital nerve block and may not have other obvious localising signs on initial examination.  

Question 80

Scenario: An older horse with a history of low-grade, bilateral forelimb lameness shows mild effusion of the distal interphalangeal (coffin) joint on palpation. Radiographs reveal periarticular osteophytes. Lead-in: What is the most likely diagnosis? Options: a) Navicular degeneration b) Pedal osteitis c) Subchondral cystic lesion d) Osteoarthritis of the distal interphalangeal joint e) Deep digital flexor tendonitis

Answer 80

Answer: d) Osteoarthritis of the distal interphalangeal joint Explanation: The signalment, clinical signs of low-grade lameness and joint effusion, and radiographic findings of periarticular osteophytes are consistent with osteoarthritis of the distal interphalangeal (coffin) joint, also known as low ringbone.

Question 81

Scenario: A horse with suspected navicular degeneration has radiographs of the feet taken, including a skyline view. Lead-in: What specific anatomical structure is best evaluated using the skyline radiographic view of the navicular bone? Options: a) The sagittal ridge of the distal phalanx b) The flexor surface of the navicular bone c) The proximal and distal borders of the navicular bone d) The collateral cartilages e) The distal interphalangeal joint space

Answer 81

Answer: c) The proximal and distal borders of the navicular bone Explanation: The skyline radiographic view is specifically used to assess the proximal and distal borders of the navicular bone for enthesiophyte formation, which is a feature of navicular degeneration.

Question 82

Scenario: A horse with osteoarthritis of the distal interphalangeal joint is being managed with corrective farriery. Lead-in: Which farriery technique is commonly employed to help unload the dorsal aspect of the coffin joint in these cases? Options: a) Applying heel wedges b) Using a bar shoe with heel support c) Shortening the toe and rolling it d) Applying a full roller motion shoe e) Using a shoe with toe grabs

Answer 82

Answer: c) Shortening the toe and rolling it Explanation: Shortening the toe and rolling it helps to ease breakover and reduce the forces on the dorsal aspect of the distal interphalangeal joint, which can be beneficial in managing osteoarthritis of this joint.

Question 83

Scenario: A horse with navicular degeneration is not responding adequately to conservative management. Lead-in: Which surgical procedure is sometimes considered as a last resort for pain relief in this condition? Options: a) Deep digital flexor tendon tenotomy b) Desmotomy of the suspensory ligament c) Palmar digital neurectomy d) Coffin joint arthrodesis e) Navicular bone resection

Answer 83

Answer: c) Palmar digital neurectomy Explanation: Palmar digital neurectomy involves the surgical sectioning of the palmar digital nerves to provide pain relief by desensitising the foot. However, it is considered a last resort due to potential complications.

Question 84

Scenario: You are examining a horse with chronic foot lameness. On hoof testers, the horse shows a marked response to pressure over the toe region. Lead-in: While this could indicate various issues, which specific finding on radiographs would make you most suspicious of pedal osteitis? Options: a) A transverse fracture of the pedal bone b) Irregular lysis of the solar margin of the distal phalanx c) A subchondral cystic lesion within the pedal bone d) Enthesiophyte formation on the distal border of the navicular bone e) Increased radiopacity of the navicular bone

Answer 84

Answer: b) Irregular lysis of the solar margin of the distal phalanx Explanation: Pedal osteitis is characterised by irregular lysis (bone loss) of the solar margin of the distal phalanx (pedal bone), often occurring secondary to chronic inflammation or concussion within the hoof.  

Question 85

Scenario: A horse with suspected navicular degeneration undergoes magnetic resonance imaging (MRI) of the feet. Lead-in: What specific finding on MRI is indicative of oedema within the navicular bone? Options: a) Cortical thickening of the navicular bone b) Increased signal intensity on T1-weighted images c) Decreased signal intensity on T2-weighted images d) Fluid accumulation (increased signal intensity) within the navicular bone on STIR sequences e) Mineralisation within the deep digital flexor tendon

Answer 85

Answer: d) Fluid accumulation (increased signal intensity) within the navicular bone on STIR sequences Explanation: MRI, particularly using STIR (Short T1 Inversion Recovery) sequences, is sensitive for detecting fluid accumulation, which appears as increased signal intensity (brighter areas) within the navicular bone in cases of navicular degeneration.  

Question 86

Scenario: A horse with chronic foot pain that blocks to a palmar digital nerve block has radiographs showing no significant abnormalities. Lead-in: According to the information on cases that block to the foot, what further imaging modality might be most useful in identifying soft tissue lesions within the foot? Options: a) Computed tomography (CT) b) Nuclear scintigraphy c) Ultrasound d) Contrast radiography e) Thermography

Answer 86

Answer: c) Ultrasound Explanation: While MRI is the gold standard for imaging soft tissues within the foot, ultrasound can be useful for evaluating structures like the digital flexor tendons and ligaments, especially if performed by an experienced operator.  

Question 87

Scenario: You are examining a horse with acute onset lameness in the left forelimb. On palpation of the left digital arteries, you note a marked increase in the amplitude of the pulse compared to the right limb. Lead-in: According to the provided material, what is the underlying physiological reason for an increased digital pulse in the foot? Options: a) Vasoconstriction due to pain b) Increased blood flow to the foot due to inflammation c) Decreased heart rate leading to increased pulse pressure d) Dehydration causing reduced blood viscosity e) Compression of the digital arteries proximal to the foot

Answer 87

Answer: b) Increased blood flow to the foot due to inflammation Explanation: An increased digital pulse amplitude typically indicates increased blood flow to the foot, which is a common finding in inflammatory conditions affecting the foot.

Question 88

Scenario: You are asked to assess the digital pulses of a horse. Lead-in: Where is the most appropriate location to palpate the digital arteries in the equine limb? Options: a) Proximal to the carpus on the dorsal aspect of the limb b) In the mid-metacarpal region on the lateral aspect of the limb c) Over the palmar aspect of the pastern, just proximal to the coronary band d) In the plantar region of the hindlimb, proximal to the hock e) On the medial aspect of the forearm, distal to the elbow

Answer 88

Answer: c) Over the palmar aspect of the pastern, just proximal to the coronary band Explanation: The digital arteries are most readily palpated over the palmar/plantar aspect of the pastern, just proximal to the coronary band, where they run alongside the digital nerves.

Question 89

Scenario: A horse presents with a history of acute onset, severe lameness, reluctance to move, and a bounding digital pulse in all four feet. The hooves are warm to the touch. Lead-in: Based on these clinical signs, what is the most likely diagnosis? Options: a) Subsolar abscess b) Pedal bone fracture c) Navicular syndrome d) Laminitis e) Deep digital flexor tendonitis

Answer 89

Answer: d) Laminitis Explanation: The combination of acute onset severe lameness, reluctance to move, bounding digital pulses in multiple feet, and warm hooves is highly characteristic of laminitis.

Question 90

Scenario: You are examining a horse with suspected laminitis. Lead-in: Which of the following is a key finding on examination that supports a diagnosis of acute laminitis? Options: a) A cold hoof with a weak digital pulse b) Pain elicited with hoof testers primarily over the frog c) Increased sensitivity to palpation over the dorsal aspect of the hoof wall at the coronary band d) A hard swelling in the palmar aspect of the foot e) Improvement of lameness after a palmar digital nerve block

Answer 90

Answer: c) Increased sensitivity to palpation over the dorsal aspect of the hoof wall at the coronary band Explanation: Increased sensitivity to palpation over the dorsal aspect of the hoof wall at the coronary band is a classic sign of acute laminitis, reflecting inflammation and pressure in the lamellar tissues.

Question 91

Scenario: Radiographs are taken of a horse's foot with chronic laminitis. Lead-in: What is a common radiographic finding in horses with laminitis? Options: a) Fracture of the pedal bone b) Osteoarthritis of the distal interphalangeal joint c) Rotation of the distal phalanx (pedal bone) d) Increased thickness of the hoof wall at the toe e) Mineralisation of the collateral cartilages

Answer 91

Answer: c) Rotation of the distal phalanx (pedal bone) Explanation: Rotation of the distal phalanx (pedal bone) away from the hoof wall is a hallmark radiographic finding in laminitis.

Question 92

Scenario: A horse is diagnosed with acute laminitis. Lead-in: What is a crucial aspect of the initial management of acute laminitis? Options: a) Encouraging exercise to promote circulation b) Applying heat to the hooves to increase blood flow c) Restricting movement and providing a deep, soft bedding d) Immediately applying hoof boots with wedge pads e) Administering high doses of corticosteroids

Answer 92

Answer: c) Restricting movement and providing a deep, soft bedding Explanation: Restricting movement on deep, soft bedding helps to support the feet and reduce further damage to the laminae in horses with acute laminitis.

Question 93

Scenario: A horse with chronic laminitis is being managed with farriery. Lead-in: Which farriery technique is often used in chronic laminitis cases to support the pedal bone and improve comfort? Options: a) Applying toe extensions b) Using lightweight aluminium shoes c) Applying heart bar shoes d) Elevating the heels significantly e) Leaving the horse barefoot

Answer 93

Answer: c) Applying heart bar shoes Explanation: Heart bar shoes provide support to the frog and the palmar/plantar section of the foot, helping to distribute weight and support the rotated pedal bone in chronic laminitis cases.

Question 94

Scenario: A horse with laminitis is being treated with medication for pain relief. Lead-in: Which class of drugs is commonly used for analgesia in the initial stages of acute laminitis? Options: a) Opioids b) Muscle relaxants c) Non-steroidal anti-inflammatory drugs (NSAIDs) d) Corticosteroids e) Bisphosphonates

Answer 94

Answer: c) Non-steroidal anti-inflammatory drugs (NSAIDs) Explanation: NSAIDs, such as phenylbutazone or flunixin meglumine, are commonly used to provide pain relief and reduce inflammation in the acute stages of laminitis.

Question 95

Scenario: A horse with chronic laminitis has a significant rotation of the pedal bone and persistent pain despite medical and farriery management. Lead-in: Which salvage surgical procedure might be considered in severe, refractory cases of rotational laminitis? Options: a) Palmar digital neurectomy b) Deep digital flexor tenotomy c) Coffin joint arthrodesis d) Navicular bone resection e) Dorsal hoof wall resection

Answer 95

Answer: b) Deep digital flexor tenotomy Explanation: Deep digital flexor tenotomy is a salvage procedure that can be considered in severe cases of rotational laminitis to reduce the pull of the deep digital flexor tendon on the pedal bone, potentially providing pain relief.

Question 96

Scenario: You are examining a horse with an increased digital pulse. Hoof testers elicit a strong pain response over the sole of the foot, particularly in the region of the white line. Lead-in: What is the most likely cause of the increased digital pulse in this case? Options: a) Pedal bone fracture b) Laminitis c) Subsolar abscess d) Navicular bursitis e) Deep digital flexor tendonitis within the foot

Answer 96

Answer: c) Subsolar abscess Explanation: Pain elicited with hoof testers over the sole, especially at the white line, along with an increased digital pulse, is highly suggestive of a subsolar (hoof) abscess.

Question 97

Scenario: A horse with chronic laminitis is being managed with a restricted diet. Lead-in: According to the provided material, what type of hay is often recommended for horses with laminitis to reduce sugar content? Options: a) Lush, green pasture hay b) Lucerne (alfalfa) hay c) Mature, stemmy hay soaked in water for one hour d) Oat hay e) Molassed hay

Answer 97

Answer: c) Mature, stemmy hay soaked in water for one hour Explanation: Mature, stemmy hay that has been soaked in water for one hour can help to reduce the sugar and non-structural carbohydrate content, which is beneficial for managing laminitis, especially in cases associated with endocrine disorders.

Question 98

cenario: A horse with laminitis shows a marked sinking of the coronary band. Lead-in: What does this clinical sign indicate about the severity of the lamellar damage? Options: a) Mild, early-stage laminitis b) Moderate laminitis with pedal bone rotation c) Severe laminitis with significant separation of the hoof wall from the pedal bone d) Chronic, well-managed laminitis e) Laminitis primarily affecting the hind limbs

Answer 98

Answer: c) Severe laminitis with significant separation of the hoof wall from the pedal bone Explanation: Sinking of the coronary band indicates a severe degree of lamellar damage and significant separation between the hoof wall and the pedal bone, suggesting a poor prognosis.

Question 99

Scenario: A horse with chronic foot lameness has a long toe and low heel hoof conformation. Lead-in: According to the principles of foot balance, what term describes this hoof-pastern axis alignment? Options: a) Broken forward b) Broken back c) Negative palmar angle d) Positive palmar angle e) Upright foot

Answer 99

Answer: b) Broken back Explanation: A long toe and low heel conformation results in a broken back hoof-pastern axis, where the angle of the hoof is less upright than the angle of the pastern.

Question 100

Scenario: You are asked to advise a farrier on corrective shoeing for a horse with a negative palmar angle. Lead-in: Which farriery technique would be most appropriate to help increase the palmar angle? Options: a) Shortening the toe b) Applying heel wedges c) Using a shoe with a rolled toe d) Applying a heart bar shoe e) Using a wider web shoe

Answer 100

Answer: b) Applying heel wedges Explanation: Heel wedges elevate the heels, which in turn increases the palmar angle, helping to improve hoof balance and reduce strain on the caudal structures of the foot.

Question 101

Scenario: A horse presents with acute onset, severe lameness in one forefoot. On examination, there is a bounding digital pulse and pain elicited with hoof testers over the medial toe region. Lead-in: What is the most likely diagnosis? Options: a) Pedal bone fracture b) Navicular syndrome c) Hoof abscess d) Laminitis e) Corn

Answer 101

Answer: c) Hoof abscess Explanation: The acute onset of severe lameness, bounding digital pulse, and localised pain on hoof testers are classic signs of a hoof abscess.

Question 102

Scenario: You are treating a horse with a hoof abscess. After locating the tract and draining pus, you advise the owner on aftercare. Lead-in: What is the most important aspect of home care for a draining hoof abscess? Options: a) Keeping the foot dry and clean b) Applying a tight bandage to prevent contamination c) Regular poulticing of the foot d) Administering systemic antibiotics for 7 days e) Restricting the horse to box rest on deep shavings

Answer 102

Answer: c) Regular poulticing of the foot Explanation: Poulticing helps to draw out any remaining infection and debris from the hoof abscess, promoting continued drainage and healing.

Question 103

Scenario: Radiographs are taken of a horse's foot that has a suspected fracture of the distal phalanx. Which radiographic view is best for visualising a sagittal fracture of the pedal bone? Lead-in: Which radiographic view is best for visualising a sagittal fracture of the pedal bone? Options: a) Lateromedial view b) Dorsopalmar view c) Palmarodorsal view d) Upright pedal bone view e) Skyline view of the navicular bone

Answer 103

Answer: b) Dorsopalmar view Explanation: A dorsopalmar (DP) view, where the X-ray beam enters the dorsal aspect of the foot and exits the palmar aspect, is the best view for visualising sagittal fractures of the pedal bone.

Question 104

Scenario: A horse with chronic foot lameness has radiographs taken. A well-defined radiolucent area is visible within the distal phalanx. Lead-in: What is the most likely diagnosis? Options: a) Pedal osteitis b) Navicular degeneration c) Subchondral cystic lesion d) Keratoma e) Hoof abscess tract

Answer 104

Answer: c) Subchondral cystic lesion Explanation: A well-defined radiolucent area within the distal phalanx is characteristic of a subchondral cystic lesion, which can be a cause of chronic foot lameness.

Question 105

Scenario: A horse presents with acute onset lameness and a bounding digital pulse. Hoof testers elicit pain over the sole near the heel. On paring the sole, a dark discolouration is noted. Lead-in: What is the most likely diagnosis? Options: a) Corn b) Solar bruising c) Keratoma d) Septic pedal osteitis e) Navicular fracture

Answer 105

Answer: b) Solar bruising Explanation: Solar bruising, caused by trauma to the sole, results in haemorrhage into the sensitive tissues, leading to pain, increased digital pulse, and a dark discolouration visible on paring the sole.

Question 106

Scenario: A horse with chronic lameness has a firm, circular mass palpable within the hoof wall at the toe region. Radiographs show a smooth, radiolucent defect in the distal phalanx adjacent to this mass. Lead-in: What is the most likely diagnosis? Options: a) Hoof abscess b) Keratoma c) Corn d) Pedal osteitis e) Subchondral cystic lesion

Answer 106

Answer: b) Keratoma Explanation: A keratoma is a hyperplastic keratin mass within the hoof wall that can cause pressure necrosis of the adjacent distal phalanx, resulting in a smooth radiolucent defect.

Question 107

Scenario: A horse with a history of a penetrating injury to the sole of the foot presents with persistent, severe lameness that is not resolving with routine hoof abscess treatment. Radiographs show osteolysis of the distal phalanx at the site of penetration. Lead-in: What is the most likely diagnosis? Options: a) Complicated hoof abscess b) Pedal osteitis c) Septic pedal osteitis d) Keratoma e) Navicular bursitis

Answer 107

Answer: c) Septic pedal osteitis Explanation: Persistent, severe lameness following a penetrating injury to the sole, along with radiographic evidence of osteolysis of the distal phalanx, is indicative of septic pedal osteitis, a bone infection.

Question 108

Scenario: A horse with chronic foot lameness has radiographs showing increased radiopacity and sclerosis of the navicular bone. Lead-in: What is the most likely diagnosis? Options: a) Pedal osteitis b) Navicular degeneration c) Distal phalangeal fracture d) Subchondral cystic lesion e) Keratoma

Answer 108

Answer: b) Navicular degeneration Explanation: Increased radiopacity and sclerosis of the navicular bone are radiographic findings consistent with navicular degeneration.

Question 109

Scenario: You are examining a horse's foot and note a small, painful area in the heel region that appears bruised and has a central dark spot on paring. The horse has been shod for longer than the usual interval. Lead-in: What is the most likely diagnosis? Options: a) Solar bruising b) Corn c) Hoof crack d) Thrush e) Canker

Answer 109

Answer: b) Corn Explanation: Corns are bruises that occur in the heel region of the sole, typically at the seat of corn, often associated with long shoeing intervals and pressure from the shoe.

Question 110

Scenario: A horse with a suspected fracture of the distal phalanx has a dorsopalmar radiograph taken. Lead-in: Which type of distal phalangeal fracture is classified as involving the extensor process? Options: a) Type I b) Type II c) Type III d) Type IV e) Type V

Answer 110

Answer: d) Type IV Explanation: Type IV distal phalangeal fractures, according to the Stubbs classification, involve the extensor process of the pedal bone.

Question 111

Scenario: A horse with a suspected fracture of the navicular bone has an upright pedal bone radiographic view taken. Lead-in: Which type of navicular fracture is typically best visualised with this view? Options: a) Transverse fracture through the body b) Sagittal fracture c) Fracture of the proximal border d) Fracture of the distal border e) Wing fracture

Answer 111

Answer: a) Transverse fracture through the body Explanation: The upright pedal bone view can help visualise transverse fractures through the body of the navicular bone.

Question 112

Scenario: A horse with a chronic foot abscess that is not resolving is radiographed. A sequestrum is identified within the distal phalanx. Lead-in: What condition is most likely present? Options: a) Pedal osteitis b) Keratoma c) Septic pedal osteitis d) Subchondral cystic lesion e) Navicular degeneration

Answer 112

Answer: c) Septic pedal osteitis Explanation: Sequestrum formation, the presence of a piece of dead bone, within the distal phalanx in association with a chronic infection is a characteristic finding in septic pedal osteitis.

Question 113

Scenario: A horse with a history of recurrent hoof abscesses at the same location is radiographed. A radiolucent tract extends from the sole to a well-defined mass within the hoof wall. Lead-in: What is the most likely diagnosis? Options: a) Complicated hoof abscess b) Keratoma c) Corn d) Foreign body e) Subsolar bruising

Answer 113

Answer: b) Keratoma Explanation: A keratoma can cause recurrent hoof abscesses at the same location due to disruption of the white line integrity and can be visualised as a mass within the hoof wall on radiographs.

Question 114

Scenario: A horse with a suspected navicular fracture has a flexor radiographic view of the navicular bone taken. Lead-in: What specific aspect of the navicular bone is best assessed with this view? Options: a) The sagittal ridge b) The proximal border c) The distal border d) The flexor surface and cortico-medullary junction e) The collateral cartilages

Answer 114

Answer: d) The flexor surface and cortico-medullary junction Explanation: The flexor radiographic view of the navicular bone is specifically designed to evaluate the flexor surface and the cortico-medullary junction for signs of degeneration or fracture.

Question 115

Scenario: A horse with chronic foot lameness has radiographs showing a distinct, symmetrical indentation at the toe of the distal phalanx. Lead-in: What is the likely significance of this finding? Options: a) Pedal osteitis b) Chronic laminitis with rotation c) Normal anatomical variation known as "crena marginalis" d) Evidence of previous subsolar abscess e) Early keratoma formation

Answer 115

Answer: c) Normal anatomical variation known as "crena marginalis" Explanation: Crena marginalis is a normal, symmetrical indentation at the toe of the distal phalanx and is not necessarily indicative of pathology. It needs to be differentiated from the irregular lysis seen in pedal osteitis or changes associated with chronic laminitis.

Question 116

Scenario: A horse with a suspected fracture of the distal sesamoid bones has standard radiographic views taken that are inconclusive. Lead-in: What further imaging modality might be most useful for diagnosing fractures of the navicular bone? Options: a) Ultrasound b) Computed tomography (CT) c) Magnetic resonance imaging (MRI) d) Nuclear scintigraphy e) Thermography

Answer 116

Answer: c) Magnetic resonance imaging (MRI) Explanation: MRI is highly sensitive for detecting fractures of the navicular bone, especially subtle or non-displaced fractures that may not be clearly visible on radiographs.

Question 117

Scenario: A horse with a corn in the heel region is being managed with farriery. Lead-in: What is a key farriery aim in the management of corns? Options: a) To increase pressure on the heel b) To eliminate pressure on the affected area c) To encourage rapid hoof growth d) To make the hoof more rigid e) To increase concussion to the foot

Answer 117

Answer: b) To eliminate pressure on the affected area Explanation: The primary aim of farriery in managing corns is to identify and eliminate the source of pressure on the sensitive tissues in the heel region that is causing the bruising and pain.

Question 118

Scenario: A horse with septic pedal osteitis is undergoing treatment. Lead-in: What is the primary goal of surgical intervention in cases of septic pedal osteitis? Options: a) To fuse the distal interphalangeal joint b) To remove any sequestrum and infected bone c) To perform a palmar digital neurectomy for pain relief d) To apply internal fixation to the pedal bone e) To encourage rapid closure of the sole penetration

Answer 118

Answer: b) To remove any sequestrum and infected bone Explanation: The primary goal of surgical treatment in septic pedal osteitis is to debride the infected bone and remove any sequestrum (dead bone) to facilitate healing and resolution of the infection.

Question 119

Scenario: A horse presents with acute onset, marked swelling of the left hindlimb from the hock distally. The limb is warm and painful to palpate, and the horse is moderately lame. Lead-in: What is the most likely underlying disease process? Options: a) Septic arthritis b) Cellulitis c) Tendon rupture d) Fracture e) Laminitis

Answer 119

Answer: b) Cellulitis Explanation: Cellulitis in horses is characterised by inflammation of the subcutaneous tissues, leading to heat, pain, and diffuse swelling, often affecting the distal limb.  

Question 120

Scenario: A horse presents with acute, severe lameness of the right hindlimb. On examination, there is significant swelling extending up the medial aspect of the limb from the fetlock, with a palpable tracking cord. Lead-in: What is the most likely diagnosis? Options: a) Cellulitis b) Lymphangitis c) Deep digital flexor tendon rupture d) Saphenaous vein thrombosis e) Rupture of the gastrocnemius muscle

Answer 120

Answer: b) Lymphangitis Explanation: Lymphangitis in horses often presents with severe lameness and a characteristic tracking cord along the course of the lymphatic vessels, with swelling that can extend proximally from the distal limb.

Question 121

Scenario: A horse is diagnosed with lymphangitis. Besides systemic antibiotics and anti-inflammatories, what additional treatment is highlighted as important in the provided material? Lead-in: Besides systemic antibiotics and anti-inflammatories, what additional treatment is highlighted as important? Options: a) Application of cold hosing only b) Strict box rest without movement c) Regular, controlled exercise d) Compression bandaging e) Intralesional steroid injections

Answer 121

Answer: d) Compression bandaging Explanation: The provided material emphasizes the importance of compression bandaging in the treatment of lymphangitis to help reduce swelling and support the lymphatic system.  

Question 122

Scenario: A horse presents with acute onset cellulitis of the hindlimb. Lead-in: What is the most appropriate first-line treatment for equine cellulitis? Options: a) Oral doxycycline once daily b) Intravenous enrofloxacin twice daily c) Intramuscular penicillin and intravenous gentamicin once daily d) Subcutaneous ceftiofur once daily e) Oral trimethoprim-sulfamethoxazole twice daily

Answer 122

Answer: c) Intramuscular penicillin and intravenous gentamicin once daily Explanation: The provided material suggests that a combination of a beta-lactam antibiotic like penicillin (given intramuscularly) and an aminoglycoside like gentamicin (often given intravenously) is a common first-line treatment for equine cellulitis.

Question 123

Scenario: A newborn foal presents with an inability to stand due to flexure of both forelimbs at the carpal joints. Lead-in: According to the provided material, what is the most likely classification of this condition? Options: a) Acquired flexural deformity b) Congenital angular limb deformity c) Congenital flexural deformity d) Acquired angular limb deformity e) Incomplete ossification of carpal bones

Answer 123

Answer: c) Congenital flexural deformity Explanation: Flexural deformities present at birth are classified as congenital. The carpal joint is a common site for congenital hyperflexion.

Question 124

Scenario: A newborn foal is born with hyperextension of the fetlock joints in all four limbs, causing the toe to be elevated off the ground. Lead-in: According to the information provided, what is the typical prognosis for this condition? Options: a) Requires immediate surgical correction b) Usually self-corrects within a few weeks c) Often associated with a poor long-term outcome for athletic function d) Indicates a severe underlying neurological disorder e) Typically requires prolonged casting

Answer 124

Answer: b) Usually self-corrects within a few weeks Explanation: Congenital hyperextension (laxity) of the distal limb joints in foals is common and usually resolves spontaneously within the first few weeks of life with confinement to a small area.

Question 125

Scenario: A newborn foal with severe congenital hyperflexion of the carpal joints is unable to stand. Medical management is being considered. Lead-in: Which of the following medications is sometimes used in the medical treatment of severe congenital flexural deformities? Options: a) Non-steroidal anti-inflammatory drugs (NSAIDs) b) Corticosteroids c) Oxytetracycline d) Muscle relaxants e) Bisphosphonates

Answer 125

Answer: c) Oxytetracycline Explanation: Oxytetracycline has been used in some cases of severe congenital hyperflexion (contracture) in foals, although the exact mechanism of action is not fully understood.

Question 126

Scenario: A 3-month-old Thoroughbred foal develops a progressive flexural deformity of the fetlock in both forelimbs, with the fetlock remaining behind vertical during weight-bearing. Lead-in: According to the classification of acquired fetlock joint contractures, what stage of deformity is this? Options: a) Stage 0 b) Stage 1 c) Stage 2 d) Stage 3 e) Stage 4

Answer 126

Answer: b) Stage 1 Explanation: Stage 1 acquired fetlock joint contracture is characterised by the fetlock remaining behind vertical during weight-bearing.

Question 127

Scenario: A foal with an acquired flexural deformity of the fetlock (Stage 1) is being treated medically. Lead-in: Which of the following farriery techniques is commonly used in the management of this condition? Options: a) Applying heel wedges b) Using a bar shoe c) Applying toe extensions d) Using glue-on shoes with heel elevation e) Leaving the foal barefoot

Answer 127

Answer: c) Applying toe extensions Explanation: Toe extensions are often used in the medical management of acquired fetlock joint contractures to encourage extension of the fetlock.

Question 128

Scenario: A foal with a Stage 2 acquired flexural deformity of the fetlock is not responding to medical management. Surgical intervention is being considered. Lead-in: Which surgical procedure is typically performed to address contracture of the superficial digital flexor tendon in these cases? Options: a) Desmotomy of the accessory ligament of the deep digital flexor tendon b) Desmotomy of the accessory ligament of the superficial digital flexor tendon c) Tenotomy of the deep digital flexor tendon d) Tenotomy of the superficial digital flexor tendon e) Capsulotomy of the fetlock joint

Answer 128

Answer: b) Desmotomy of the accessory ligament of the superficial digital flexor tendon Explanation: For acquired fetlock joint contractures involving the superficial digital flexor tendon, desmotomy (surgical cutting) of the accessory (check) ligament of the SDFT is a common surgical treatment.

Question 129

Scenario: A foal with a severe acquired flexural deformity of the fetlock (Stage 3) has not improved with superficial digital flexor tendon check ligament desmotomy. Lead-in: Which additional surgical procedure might be considered if the deep digital flexor tendon is also contributing to the contracture? Options: a) Desmotomy of the suspensory ligament b) Tenotomy of the superficial digital flexor tendon c) Desmotomy of the accessory ligament of the deep digital flexor tendon d) Capsulotomy of the distal interphalangeal joint e) Neurectomy of the palmar digital nerves

Answer 129

Answer: c) Desmotomy of the accessory ligament of the deep digital flexor tendon Explanation: If the deep digital flexor tendon is also contributing to a severe fetlock contracture, desmotomy of the accessory (check) ligament of the DDFT might be performed in addition to the SDFT check ligament desmotomy.

Question 130

Scenario: A foal is diagnosed with a mild congenital flexural deformity of the carpus. Lead-in: What is the typical initial management for this condition? Options: a) Immediate casting of the limb b) Strict box rest with no exercise c) Light exercise and observation d) Surgical correction with transphyseal screws e) Intravenous administration of corticosteroids

Answer 130

Answer: c) Light exercise and observation Explanation: Mild congenital flexural deformities, particularly at the carpus, often improve with light exercise and observation as the foal gains strength.

Question 131

Scenario: An older foal (10 months old) develops an acquired flexural deformity of the fetlock. Nutritional factors are being considered. Lead-in: Which dietary management strategy might be beneficial in some cases of acquired flexural deformity in older foals? Options: a) Increasing protein intake to promote tendon growth b) Restricting calorie intake to slow bone growth c) Supplementing with high levels of calcium d) Feeding a high-starch diet for increased energy e) Restricting access to pasture

Answer 131

Answer: b) Restricting calorie intake to slow bone growth Explanation: In older foals with acquired flexural deformities, especially rapid-growing individuals, restricting calorie intake to slow the rate of bone growth relative to tendon length can sometimes be beneficial.

Question 132

Scenario: A foal with a flexural deformity is being evaluated. Radiographs are taken. Lead-in: What is the primary reason for taking radiographs in a foal with a flexural deformity? Options: a) To assess the severity of tendon contracture b) To evaluate the degree of joint effusion c) To rule out concurrent bony abnormalities or incomplete ossification d) To determine the prognosis for athletic function e) To guide the surgical approach

Answer 132

Answer: c) To rule out concurrent bony abnormalities or incomplete ossification Explanation: While radiographs may show secondary changes, the primary reason for radiography in a foal with a flexural deformity is to rule out other concurrent problems such as bony abnormalities or incomplete ossification of the carpal or tarsal bones.

Question 133

Scenario: A foal with a congenital flexural deformity of the coffin joint is preventing it from bearing weight normally. Lead-in: Which of the following treatments is often used for this specific type of congenital flexural deformity? Options: a) Full limb cast b) Intravenous regional limb perfusion with antibiotics c) Toe extensions or glue-on shoes d) Surgical arthrodesis of the coffin joint e) Acupuncture

Answer 133

Answer: c) Toe extensions or glue-on shoes Explanation: Congenital flexural deformities of the coffin joint are often managed with toe extensions or glue-on shoes to help stretch the flexor tendons and encourage a more normal stance.

Question 134

Scenario: A foal that underwent surgical correction for a severe flexural deformity is now in the rehabilitation phase. Lead-in: What is a key aspect of the rehabilitation plan for these foals? Options: a) Prolonged strict box rest for several months b) Gradual, controlled exercise to promote tendon strength and flexibility c) Aggressive physiotherapy with forced joint flexion and extension d) Early turnout to pasture for unrestricted movement e) Repeated surgical release of tendons if contracture recurs

Answer 134

Answer: b) Gradual, controlled exercise to promote tendon strength and flexibility Explanation: Gradual, controlled exercise is crucial during the rehabilitation phase after surgical correction of flexural deformities to help the tendons regain strength and flexibility and to prevent recurrence of the contracture.

Question 135

Scenario: A 7-day-old foal presents with lameness, reluctance to stand, and a swollen, painful fetlock joint. The foal also has a history of umbilical infection. Lead-in: According to the provided material, which of the following abnormalities is most likely associated with an increased risk of this condition? Options: a) Plasma IgG concentration of 900 mg/dL b) Patent urachus c) Prematurity d) Fetlock joint laxity e) Absence of diarrhoea

Answer 135

Answer: b) Patent urachus Explanation: Patent urachus, along with omphalophlebitis (inflammation of the umbilical vein), is associated with an increased risk of haematogenous spread of bacteria leading to septic arthritis, physitis, and osteomyelitis (SAPO) in foals

Question 136

Scenario: A 3-day-old foal presents with lameness and effusion of the fetlock joint. The foal is reluctant to stand, and its rectal temperature is 37.6°C. Lead-in: What is the most likely diagnosis based on these clinical signs? Options: a) Fractured limb b) Septic arthritis c) Tendon rupture d) Angular limb deformity e) Incomplete ossification

Answer 136

Answer: b) Septic arthritis Explanation: The most common presenting signs of septic arthritis in a young foal are lameness and effusion of the affected joint, along with reluctance to stand [cite: 4. SDL - Quiz - Osteomyelitis and joint sepsis MCQs.pdf]. While a fever can be present, a normal or low temperature does not rule out sepsis.

Question 137

Scenario: A 6-week-old foal presents with distension of the tibiotarsal joint and swelling and heat on the dorsolateral aspect of the limb just proximal to the joint. Lead-in: Radiography is performed to highlight the dorsolateral aspect of the physis. Which radiographic projection will provide the best diagnostic image of this region? Options: a) 45° dorsolateral-plantaromedial oblique b) 45° dorsomedial-plantarolateral oblique c) Lateromedial d) Dorso-plantar e) Plantaroproximal-plantarodistal with the limb in a flexed position

Answer 137

Answer: b) 45° dorsomedial-plantarolateral oblique Explanation: A 45° dorsomedial-plantarolateral oblique radiographic projection is best to highlight the dorsolateral aspect of the physis in the distal tibia [cite: 4. SDL - Quiz - Osteomyelitis and joint sepsis MCQs.pdf].

Question 138

Scenario: A foal is diagnosed with septic physitis of the distal tibia. Lead-in: Which of the following would be the most appropriate therapeutic regime in addition to surgical debridement under general anaesthesia? Options: a) Ceftiofur IV, flunixin IV, repeat radiography after 14 days b) Sodium penicillin and gentamicin IV, flunixin IV, clinical reassessment of lameness after 5 days of therapy c) Rifampin PO, meloxicam IV, measurement of serum amyloid A after 5 days of therapy d) Clarithromycin PO, meloxicam IV, repeat arthroscopy under general anaesthesia after 5 days of therapy e) Oral doxycycline once daily

Answer 138

Answer: b) Sodium penicillin and gentamicin IV, flunixin IV, clinical reassessment of lameness after 5 days of therapy Explanation: The most appropriate initial antimicrobial therapy for septic arthritis and physitis in foals typically involves broad-spectrum bactericidal antibiotics such as sodium penicillin and gentamicin administered intravenously, along with an NSAID like flunixin for anti-inflammatory effects. Clinical reassessment is crucial to monitor response to treatment [cite: 4. SDL - Quiz - Osteomyelitis and joint sepsis MCQs.pdf].

Question 139

Scenario: A foal with septic arthritis of the stifle joint has undergone initial treatment. Lead-in: According to the information provided, what is the most common bacterial isolate in cases of haematogenous septic arthritis in foals? Options: a) Escherichia coli b) Streptococcus spp. c) Staphylococcus spp. d) Klebsiella pneumoniae e) Actinobacillus equuli

Answer 139

Answer: b) Streptococcus spp. Explanation: Streptococcus spp. are the most common bacterial isolates in cases of haematogenous septic arthritis in foals [cite: 4. Haematogenous septic arthritis, physitis and osteomyelitis in foals Part 2.pdf].

Question 140

Scenario: A foal with septic arthritis is being treated with intravenous antibiotics. Lead-in: According to the information, what is the recommended duration of intravenous antibiotic treatment for septic arthritis in foals? Options: a) 3-5 days b) 5-7 days c) 7-14 days d) 2-4 weeks e) Until the foal is sound

Answer 140

Answer: c) 7-14 days Explanation: The recommended duration of intravenous antibiotic treatment for septic arthritis in foals is generally 7-14 days, followed by oral antibiotics for an additional 2-4 weeks [cite: 4. Haematogenous septic arthritis, physitis and osteomyelitis in foals Part 2.pdf].

Question 141

Scenario: A foal with septic arthritis of the carpus has undergone joint lavage. Lead-in: According to the information, which of the following intra-articular antibiotics is commonly used in foals? Options: a) Enrofloxacin b) Gentamicin c) Ceftiofur d) Metronidazole e) Tetracycline

Answer 141

Answer: b) Gentamicin Explanation: Gentamicin is a commonly used intra-articular antibiotic in foals with septic arthritis, often administered after joint lavage [cite: 4. Haematogenous septic arthritis, physitis and osteomyelitis in foals Part 2.pdf].

Question 142

Scenario: A foal is diagnosed with osteochondrosis dissecans (OCD) of the stifle joint. Lead-in: According to the information, what is the underlying pathogenesis of OCD? Options: a) Bacterial infection of the joint cartilage b) Viral-induced inflammation of the synovium c) Failure of endochondral ossification d) Traumatic injury to the subchondral bone e) Nutritional deficiency of calcium and phosphorus

Answer 142

Answer: c) Failure of endochondral ossification Explanation: Osteochondrosis dissecans (OCD) results from a focal failure of endochondral ossification at the articular-epiphyseal cartilage complex [cite: 5. Juvenile joint disease - Osteochondral and subchondral pathology.pdf].

Question 143

Scenario: A yearling Thoroughbred presents with a mild to moderate lameness that worsens after flexion of the hock. Radiographs reveal a medium-sized, rectangular, radiodense lesion on the dorso-distal aspect of the radial carpal bone. Lead-in: What is the most likely diagnosis? Options: a) Septic arthritis b) Osteochondral fragmentation (OCF) of the radial carpal bone c) Subchondral bone cyst d) Physitis of the distal radius e) Carpal fracture

Answer 143

Answer: b) Osteochondral fragmentation (OCF) of the radial carpal bone Explanation: The radiographic finding of a radiodense lesion on the dorso-distal aspect of the radial carpal bone in a yearling with lameness exacerbated by flexion is typical for OCF of the radial carpal bone [cite: 5. Juvenile joint disease - Osteochondral and subchondral pathology.pdf].

Question 144

Scenario: A foal is diagnosed with a subchondral bone cyst in the medial femoral condyle of the stifle joint. Lead-in: According to the information, what is a common treatment option for subchondral bone cysts? Options: a) Systemic antibiotics b) Intra-articular corticosteroids only c) Surgical debridement and bone grafting d) External coaptation with a cast e) Rest and NSAIDs only

Answer 144

Answer: c) Surgical debridement and bone grafting Explanation: Treatment options for subchondral bone cysts often include surgical debridement of the cyst and packing with bone graft material to promote healing [cite: 5. Juvenile joint disease - Osteochondral and subchondral pathology.pdf].

Question 145

Scenario: A foal presents with swelling and pain at the level of the distal radius. Radiographs show widening of the physis without a distinct fracture line. Lead-in: What is the most likely diagnosis? Options: a) Septic arthritis b) Physitis c) Physeal fracture (Salter-Harris Type I) d) Angular limb deformity e) Incomplete ossification

Answer 145

Answer: b) Physitis Explanation: Physitis is characterised by inflammation of the growth plate (physis), causing swelling and pain at the affected site, with radiographic findings of physeal widening without a clear fracture line [cite: 1. Introduction to neonate orthopaedic disease.pdf].

Question 146

Scenario: A foal sustains a traumatic injury to the distal metatarsus, and radiographs reveal a fracture through the growth plate extending out through the epiphysis into the joint. Lead-in: According to the Salter-Harris classification, what type of physeal fracture is this? Options: a) Type I b) Type II c) Type III d) Type IV e) Type V

Answer 146

Answer: c) Type III Explanation: A Salter-Harris Type III fracture involves a fracture through the growth plate and extending out through the epiphysis into the joint [cite: 1. Introduction to neonate orthopaedic disease.pdf].

Question 147

Scenario: A premature foal is born with peri-articular laxity in the carpal joints. Radiographs reveal that the carpal bones appear more rounded with a larger cartilage component than expected for its gestational age. Lead-in: What is the most likely underlying condition? Options: a) Septic arthritis b) Angular limb deformity (congenital) c) Incomplete ossification of cuboidal bones d) Flexural deformity (congenital) e) Physeal fracture

Answer 147

Answer: c) Incomplete ossification of cuboidal bones Explanation: Incomplete ossification of the carpal and tarsal cuboidal bones is common in premature or dysmature foals and is characterised by peri-articular laxity and radiographic findings of rounded bones with a significant cartilage component [cite: 1. Introduction to neonate orthopaedic disease.

Question 148

Scenario: A foal with incomplete ossification of the carpal bones is being managed. Lead-in: What is a key aspect of the management for this condition? Options: a) Aggressive exercise to stimulate bone growth b) Prolonged casting of the limb c) Strict box rest with controlled exercise d) Surgical fusion of the carpal joints e) Administration of corticosteroids to reduce inflammation

Answer 148

Answer: c) Strict box rest with controlled exercise Explanation: Management of incomplete ossification of cuboidal bones typically involves strict box rest to minimise compression on the cartilage, with the possibility of controlled exercise as ossification progresses [cite: 1. Introduction to neonate orthopaedic disease.pdf].

Question 149

Scenario: A foal with septic arthritis of the hock has undergone initial treatment. What is a factor associated with a poorer prognosis for survival and return to athletic function? Lead-in: What is a factor associated with a poorer prognosis? Options: a) Foal younger than 7 days old at presentation b) Involvement of only one joint c) Isolation of Streptococcus spp. d) Rapid response to initial antibiotic therapy e) Normal plasma IgG concentration at presentation

Answer 149

Answer: a) Foal younger than 7 days old at presentation Explanation: Younger age at presentation (<7 days old) is a factor associated with a poorer prognosis in foals with septic arthritis [cite: 4. Haematogenous septic arthritis, physitis and osteomyelitis in foals Part 2.pdf]. Involvement of multiple joints, isolation of certain bacterial species, and a poor response to initial therapy are also negative prognostic indicators.

Question 150

Scenario: An older horse presents with a history of progressive, low-grade lameness that is worse after exercise and improves with rest. Lead-in: According to the information, what is the most likely underlying cause of this presentation? Options: a) Acute tendonitis b) Septic arthritis c) Osteoarthritis d) Soft tissue abscess e) Fracture

Answer 150

Answer: c) Osteoarthritis Explanation: Progressive lameness that worsens with exercise and improves with rest is a common clinical sign of osteoarthritis in horses.

Question 151

Scenario: A horse with suspected osteoarthritis of the carpal joint has radiographs taken. Lead-in: Which of the following is a common radiographic finding associated with osteoarthritis? Options: a) Decreased joint space b) Periarticular soft tissue swelling only c) Subchondral bone lysis only d) Increased joint space e) Normal joint margins

Answer 151

Answer: a) Decreased joint space Explanation: Osteoarthritis is characterised by the progressive loss of articular cartilage, which leads to a narrowing of the joint space visible on radiographs.  

Question 152

Scenario: A horse with osteoarthritis is being managed medically for pain relief. Lead-in: Which class of medications is most commonly used for long-term pain management in horses with osteoarthritis? Options: a) Opioids b) Muscle relaxants c) Non-steroidal anti-inflammatory drugs (NSAIDs) d) Corticosteroids (systemic) e) Antibiotics

Answer 152

Answer: c) Non-steroidal anti-inflammatory drugs (NSAIDs) Explanation: NSAIDs are the mainstay of long-term pain management for osteoarthritis in horses due to their analgesic and anti-inflammatory properties.  

Question 153

Scenario: A horse with end-stage osteoarthritis of the distal tarsal joints is experiencing chronic pain that is affecting its quality of life. Lead-in: Which salvage surgical procedure might be considered for pain relief in this case? Options: a) Arthroscopy b) Arthrocentesis c) Arthrodesis d) Neurectomy of the palmar digital nerves e) Intra-articular corticosteroid injection

Answer 153

Answer: c) Arthrodesis Explanation: Arthrodesis, or surgical fusion of the joint, can be a salvage procedure for end-stage osteoarthritis in low-motion joints like the distal tarsal joints to eliminate pain.  

Question 154

Scenario: A horse that was previously performing well in dressage has shown a gradual decline in performance, particularly with canter transitions, but no obvious lameness at trot. Lead-in: According to the workshop on poor performance, what might be a subtle underlying cause to investigate? Options: a) Obvious forelimb lameness at walk b) Severe hindlimb lameness at trot c) Subtle musculoskeletal pain, potentially in the back or hind limbs d) Respiratory disease causing exercise intolerance e) Poor rider ability

Answer 154

Answer: c) Subtle musculoskeletal pain, potentially in the back or hind limbs Explanation: A decline in performance without obvious lameness can be a sign of subtle musculoskeletal pain, which may affect the horse's ability to perform specific movements like canter transitions.  

Question 155

Scenario: A horse with subtle poor performance is suspected of having pain originating from the impinging dorsal spinous processes (kissing spines). Lead-in: Which diagnostic technique involving local anaesthesia might be used to investigate this? Options: a) Palmar digital nerve block b) Intra-articular injection of the carpal joint c) Injection of local anaesthetic lateral and medial to the impinging dorsal spinous processes d) Peroneal nerve block e) Sacroiliac joint injection

Answer 155

Answer: c) Injection of local anaesthetic lateral and medial to the impinging dorsal spinous processes Explanation: Injecting local anaesthetic around the dorsal spinous processes can help to temporarily alleviate pain from kissing spines and assess if this is contributing to the poor performance.  

Question 156

Scenario: A horse with osteoarthritis of the distal interphalangeal joint is being managed with intra-articular medication. Lead-in: Which of the following medications is commonly used intra-articularly for its chondroprotective and anti-inflammatory effects in osteoarthritis? Options: a) Phenylbutazone b) Firocoxib c) Hyaluronic acid d) Ketoprofen e) Prednisolone (systemic)

Answer 156

Answer: c) Hyaluronic acid Explanation: Hyaluronic acid is a common intra-articular medication used in the management of osteoarthritis due to its viscoelastic and chondroprotective properties.  

Question 157

Scenario: A horse with end-stage osteoarthritis of the hock is being considered for euthanasia. Lead-in: According to the information on end-stage OA, what is an important factor to assess when considering euthanasia for chronic orthopaedic pain? Options: a) The horse's age b) The owner's financial situation only c) The severity of pain and the horse's quality of life d) The horse's breed e) Whether the horse is insured

Answer 157

Answer: c) The severity of pain and the horse's quality of life Explanation: Assessing the severity of the horse's pain and its impact on its overall quality of life are crucial factors when considering euthanasia for end-stage osteoarthritis.  

Question 158

Scenario: A horse with subtle hindlimb lameness and poor performance is being evaluated with diagnostic anaesthesia. A perineural block of the tibial and peroneal nerves at the level of the hock eliminates the lameness. Lead-in: Where is the most likely origin of the pain? Options: a) Distal to the fetlock b) Within the foot c) Between the fetlock and hock d) At or proximal to the hock e) Within the stifle joint

Answer 158

Answer: d) At or proximal to the hock Explanation: Blocking the tibial and peroneal nerves at the level of the hock desensitises the structures at and distal to the hock. Elimination of lameness with this block indicates the pain is originating from this region.

Question 159

Scenario: A horse with chronic osteoarthritis of the pastern joint is being managed. The owner is asking about non-medical therapies. Lead-in: Which of the following non-medical therapies is often used in the management of osteoarthritis in horses? Options: a) Acupuncture b) Chiropractic adjustment c) Controlled exercise d) Magnetic therapy e) Herbal supplements only

Answer 159

Answer: c) Controlled exercise Explanation: Controlled exercise is a key component of managing osteoarthritis in horses, helping to maintain joint mobility and muscle strength.   =