Equine MidSem 2 Exam Flashcards
List the 5 standard radiographs for the distal extremity.
Standing on a block:
- Lateromedial
- Dorsopalmar / dorsoplantar (zero degree)
Standing on a tunnerl (or special block):
- Dorsal 65 degree proximal palmarodistal oblique (distal phalanx / “upright pedal”)
- Dorsal 65 degree proximal palmarodistal oblique (navicular bone)
- Palmaroproximal palmarodistal oblique (navicular skyline)
List the 5 standard radiographic view for the fetlock.
Standing:
- Lateromedial (LM)
- Dorsopalmar / plantar (DP) & dorsal 15 degree proximal-palmarodistal oblique
- Dorsolateral palmaromedial oblique (DLPMO)
- Dorsomedial palmarolateral oblique (DMPLO)
Flexed:
- Lateromedial (LM)
List the standard views for carpus radiographs.
- Dorsopalmar (DP)
- Lateromedial (LM)
- DMPLO 45
- DLPMO 30
- Flexed lateral
- Skyline distal row
Define Lameness.
Any gait abnormality including:
- Limping, hobbling
- Incapacity of properly using one or multiple legs
- Generally caused by pain in horses - eviction strategy
- But can be of mechanic or neurologic origin
What are the 10 steps of a lameness exam?
- History
- Examination from a distance
- Palpation
- Movement
- Selected tests - manipulation, flexion, direct pressure, wedge
- Diagnostic analgesia
- Imaging
- Diagnosis
- Management
- Follow up examination
What are the 4 main stages / questions of a lameness examination?
- Is it lameness?
- Which leg(s) is it? Notions of primary, secondary & compensatory
- Which part of the leg(s) is affected?
- What is the nature of the lesion?
What is the difference between primary, secondary & compensatory lameness?
Primary lameness = the leg that hurts the most (real intense lameness)
Secondary lameness = real lameness but intensity is lower than primary
Compensatory lameness = compensatory by other areas / legs due to primary lameness (without the primary lameness the compensatory goes away)
What are some of the most common lameness findings?
- 60:40 ratio of FL to HL
- FL up to 95% distal to carpus
- In the foot until proven otherwise
- Owners often think it is behind when it is actually in front & vice versa
What does the concept “down on the sound” mean in terms of lameness?
- Head & neck elevate when the lame limb is weight bearing
- Head & neck nod down when the sound limb is weight bearing (“down on the sound”)
If the front & hind diagonal limbs (contralateral sides) appear lame / affected - where is primary lameness coming from?
If it is the front & hind limbs on the same side that both appear lame - where is primary lameness coming from?
- If it is front & hind diagonal limbs (contralateral sides) that both appear lame / affected – primary lameness is more likely to come from the front leg
- If it is front & hind limbs on the same side that both appear lame / affected – primary lameness is more likely to come from the hind leg
What are the 5 AAEP grades of lameness?
- Grade 0 = not perceptible under any circumstances
- Grade 1 = difficult to observe & not consistently apparent regardless of the circumstances
- Grade 2 = difficult to observe at a walk or when trotting on straight line but consistently apparent under certain circumstances
- Grade 3 = consistently observable at a trot under all circumstances
- Grade 4 = obvious at a walk
- Grade 5 = minimal weight bearing in motion or at rest / complete inability to move
Define valgus & varus & possible causes for it.
Valgus = limb deviates laterally distal to a reference point (+/- supernation of carpus / fetlock)
Varus = limb deviates medially distal to a reference point (+/- pronation of carpus / fetlock)
Aetiology:
- Perinatal factors - malposition, placentitis, nutrition, premature or dysmature foals
- Developmental factors - poor nutrition, excessive exercise & trauma
- Most commonly: disproportionate growth of metaphyseal growth plates
Prognosis:
- The more deviation there is the less chance of spontaneous correction
Discuss incomplete ossification of carpal / tarsal bones.
- Cuboidal bones have rounded edges
- Common congenital induced angular limb deformity - prematurity or dysmaturity
- Can also occur in normal foals
- Failure to diagnose & treat in 1st few days of life > wedge shaped cuboidal bones > permanent damage
- Diagnosis: radiographs
Treatment:
- Can be manually corrected early on
- Restrict exercise and/or provide external support
- Typically 2-4 weeks to allow for ossification
Discuss assymetric growth of metaphysis & epiphysis.
- From birth or develops in 1st weeks / months of life
- Trauma likely major cause of asymmetric growth (asymmetric compression on physis)
Diagnosis:
- Radiographs – asymmetric longitudinal growth of metaphysis or epiphysis
Treatment:
- Physeal growth rates determine rate of correction by modifying chondral growth patterns
- Total amount of growth remaining determines amount of correction achievable
- Chondral growth patterns are modified with: exercise control, farriery (trimming, shoeing), surgery (growth retardation > transphyseal bridging / screws), (growth acceleration > periosteal elevation & transection)
- Treatment method depends on: joint involved, degree of deformity, amount of growth remaining
Treatment for young foals with mild to moderate ALD:
- Stall rest 2 weeks (fetlock), 8 weeks (carpus) > autocorrection possible
- Resolution before end of rapid growth phase - if no resolution > surgery
Discuss hyperextension deformity (laxity).
- Toe does not touch the ground
- Congenital or acquired
- Mostly occurs in immature & dysmature foals
- Occurs in hindlimbs > front limbs
- Lack of flexor tone
Aetiology:
- Idiopathic
- Bandaging / casting
- Lack of exercise
- Overgrown hooves
Mild deformities:
- Respond to time & controlled exercise
Moderate & non-responsive deformities:
- Glue on extended heel shoe
- May need to bandage foot & fetlock
- Thick bandages contraindicated > more soft tissue relaxation
*Most foals correct in 2-6 weeks
Discuss flexural deformities (“contracted tendons”).
- Length disparity between tendons & bones
- Occurs in forelimbs > hindlimbs
- Structures affected: fetlock, coffin join (DIP), carpus (worse prognosis), determine if SDFT, DDFT, SL
Congenital flexural deformities aetiology:
- Uterine malpositioning
- Teratogens (locoweed, sudan grass, influenza)
- Hypothyroidism
- Neuromuscular disorder
- Genetic factors
- Nutritional imbalances in pregnant mare
Congenital flexural deformities - treatment:
- Begin ASAP
- Younger foals respond better to treatment
- Combine medical & physical therapy
- Farrier - toe extensions
- Oxytetracycline - chelation of calcium ion
We need to increase exercise in angular limb deformities or flexural deformities to improve outcome?
- Angular limb deformities we need to decrease exercise
- Vs. Flexural deformities we need to increase exercise
Tendonitis / Desmitis - list the different phases of healing.
Inflammatory phase:
- Vascular & cellular
Repair phase:
- Fibroblasts
- Intrinsic & extrinsic repair
Remodelling phase - end result:
- Decreased tensile strength
- Decreased elasticity
Discuss the pathogenesis of flexor tendinitis.
- Gradual accumulation of fatigue & progressive impact on collagen – main cause high intensity exercise / training for young horses
- Progressive degeneration of the SDFT
- Excessive stress overstretches & ruptures the collagen fibre bundles
- Low-grade tendon fibre disruption results in an accelerating cycle of inflammation, degeneration & further tendon disruption
- Acute mechanical failure results in partial (usually) tendon rupture
- Muscle is fatigued > prevents it from relaxing > injury
Discuss SDFT (Superficial Digital Flexor Tendon) Tendinitis.
Racehorses:
- Up to 30% suffer from tendon injury
- 4% fatal injuries in flat racing
- 11% of fatal injuries in races with jumps
Risk factors:
- Track design, surface type & condition
- Fitness, hoof trimming & shoeing
- Re-injury is common
- Forelimbs most commonly affected
Clinical signs:
- Moderate to severe injury – heat, swelling of SDFT & lameness
- Mild cases – slight pain on firm palpation
- Chronic cases – very large & thickened
- ‘Low bows’ – digital sheath swelling
Diagnosis:
- Clinical signs
- Thermography - low specificity
- Ultrasonography - transverse & longitudinal (must use both)
- Reduced echogenicity - anechoic
- Disruption of linear fibril pattern
Essential / most effective therapy:
- Physiotherapy - cold water hydrotherapy & padded support bandage
- Anti-inflammatory drugs - NSAIDs (or corticosteroids) +/- topical DMSO (Dimethyl Sulfoxide)
- Exercise - stall rest & controlled walking only
- Controlled rehabilitation program - low impact exercise (water walking)
Surgical treatment:
- Tendon splitting - now outdated.
- Superior check ligament desmotomy - transection of superior check ligament (SCL) alters functional length of SDFT & mechanics. Concept = cutting the limiting fibres > longer function of the tendon > transfers centre of pressure / force to whole tendon & muscle (rather than in scar tissue)
- Annular ligament desmotomy
How long does it take to recover from a tendon injury vs. a ligament injury?
Tendon injury = ~6 months (“tendon” has 6 letters)
Ligament injury = ~8 months (“ligament” has 8 letters)
Descibre how to examine the muscular system.
- History
- Physical exam - inspection (asymmetry), palpation (of several muscles) & percussion (with a hammer), gait analysis
Biochemical parameters:
- CK - increased CK related to cell lysis. >100,000 IU/L, peak at 4-6h, T1/2 12h, abnormal is >2-4 fold increase from baseling
- AST - peak 12-24h, T1/2 7-8 days
- LDH - extra analysis but not essential
- Urinalysis - myoglobinuria
Advanced diagnostic testing:
- Plasma Vit E & selenium
- Muscle biopsy - epaxial, gluteal or semimembranosus
- Genetic testing
- Exercise testing - rule out other diseases (e.g. colic due to severe water loss via sweating). Demonstrate mild increase of muscle enzyme activity by provoke test.
- Ultrasonography - depth of muscle
- Electromyography (EMG) - evaluation of muscle tone
Define myotonia vs. myopathy vs. muscle atrophy.
Mytonia = something wrong with the muscle tone.
Myopathy = something wrong with the muscle fibre e.g. muscle necrosis (rhabdomyolysis / “tying up”), non-exertional
Muscle atrophy = no muscle present due to a neurogenic or myogenic problem e.g. denervation / dis-use
Discuss exertional rhabdomyolysis (“tying up”) syndrome.
History:
- Episodes of post-exercise muscle stiffness
- Changes in training or management
Clinical signs:
- Muscle cramping and/or stiffness
- Muscle pain especially of lumbar & sacral regions
- Sweating, tachycardia, tachypnoea
- Reluctance to move
- Myoglobinuria
Diagnosis:
- Myoglobinuria
- Plasma CK & AST activities
Treatment - supportive:
- IV or oral fluids - maintain urine output to prevent or minimise the nephrotoxic effects of myoglobin & maintain circulation to muscle tissue
- Analgesics - NSAIDs (be careful - kidney insult), opiates
- Keep warm
- Acepromazine
- Vit E / Selenium
- Stall rest
Treatment - long term:
- Rest & regular (daily) turn-out
- Regular daily exercise
- Diet - fat based diet (rice bran, oils) instead of easily digestible carbs, Vit E / Selenium, electrolytes
Where is the label correctly placed on a radiograph relative to the limb?
- Medially & dorsally
- Laterally & caudally
- Laterally & dorsally
- Medially & caudally
- Laterally & dorsally
The dorsal 45 degree proximal distal oblique radiograph of the foot highlights:
- The distal border of the navicular bone
- The distal interphalangeal joint margins
- The proximal margin of the navicular bone
- The flexor cortex of the navicular bone
- The proximal margin of the navicular bone
Hallmarks of chronic laminitis include:
- Reduction of the solar margin-distal phalanx angle, remodelling of the extensor process of the distal phalanx, dorsal distal hoof wedge formation & osteolysis of the tip of the distal phalanx
- Increase of the solar margin-distal phalanx angle, dorsal hoof wedge formation, osteolysis of the extensor process of the distal phalanx & rotation of the distal phalanx realtive to the dorsal hoof wall
- Dorsal distal hoof wedge formation, remodelling of the palmar processes of the distal phalanx, reduction of the solar margin-distal phalanx angle & rotation of the distal phalanx relative to the dorsal hoof wall
- Osteolysis of the tip of the distal phalanx, rotation of the distal phalanx relative to the dorsal hoof wall, increase of the solar margin-distal phalanx angle & dorsal hoof wedge formation
- Osteolysis of the tip of the distal phalanx, rotation of the distal phalanx relative to the dorsal hoof wall, increase of the solar margin-distal phalanx angle & dorsal hoof wedge formation
Why is one of the standard projections of the fetlock a dorsal 15 degree proximal-palmar distal oblique & not a dorsal 0 degree proximal-palmar (horizontal DP)?
- It elevates the proximal sesamoid bones so that we can see the joint space better
- It elevates the proximal sesamoid bones so that we see the proximal phalanx margin chip fractures better
- It lowers the proximal sesamoid bones so that we can see the joint space better
- It lowers the proximal sesamoid bones so that we can see proximal phalanx margin chip fractures better
- It elevates the proximal sesamoid bones so that we can see the joint space better
This angle provides a clearer view of the joint space compared to a horizontal DP view because it reduces superimposition of the sesamoid bones over the joint.
Which two projections of the carpus give you the best assessment of the third carpal bone?
- The flexed dorsal 30 degree proximal-dorsal distal oblique & DLPMO
- The DMPLO & flexed lateral
- The flexed dorsal 30 degree proximal-dorsal distal oblique & DMPLO
- The flexed dorsal 45 degree proximal-dorsal distal oblique & flexed lateral
- The flexed dorsal 30 degree proximal-dorsal distal oblique & DLPMO
Which standard radiographic projection of the tarsus highlights the most common site of osteoarthritis of the distal intertarsal & tarsometatarsal joints?
- The DLPMO
- The LM
- The DP
- The DMPLO
- DLPMO
Of the following which is more accurate regarding a time dependent antimicrobial?
- It has better bactericidal effects than concentration dependent antimicrobials
- Doubling the dose (e.g. from 10mg to 20mg) will significantly increase the rate of microbial killing
- Doubling the frequency of drug administration (e.g. from q12h to q6h) will likely increase of the rate of microbial killing
- It has worse bactericidal effects than concentration dependent antimicrobials
- Doubling the frequency of drug administration (e.g. from q12h to q6h) will likely increase of the rate of microbial killing
Which of the following options describes the chronological order & initial treatment of an acutely burned horse best?
- Cooling of affected area for 5 min & IV fluid therapy
- Cooling of affected area for 20 min & ice boot application
- Cooling of affected area for 15 min & systemic analgesia
- Cooling of affected area for 10 min & IV clenbuterol administration
- Cooling of affected area for 20 min & ice boot application
A two day old colt was diagnosed with a bilateral stage II flexural deformity of the metocarpophalangeal joint. Which of the following statements is correct?
- Stall rest & heel extensions will likely correct the deformity
- Controlled exercise & stable bandages will correct the deformity within 2 weeks
- Medical management using oxytetracycline & NSAIDs has a good prognosis
- Inferior check ligament desmotomy has to be considered for the best outcome
- Medial management using oxytetracycline & NSAIDs should be attempted first
Please indicate the false statement about impingement of the dorsal spinous process (“kissing spine”).
- Surgical resection of one out of two processes is the only long-term treatment available
- It is a true arthropathy
- It is more frequent between T12 & T18
- It is the most frequent abnormality found on radiographs of the back
- It is a true arthropathy
Please indicate the correct statement about the etiopathogenesis of osteoarthritis.
- Since the articular cartilage is fully capable to repair itself, weare & tear is rarely the cause of osteoarthritis
- Only when left untreated septic arthritis can cause significant damage to the cartilage & lead to osteoarthritis
- Ligament damage resulting in major joint instability will certainly lead to osteoarthritis
- Malnutrition is a common cause of osteoarthritis, thus ensuring adequate nutrition can practically eliminate osteoarthritis
- Ligament damage resulting in major joint instability will certainly lead to osteoarthritis
You diagnose a 4 year old intact male Thoroughbred race horse of an estimated weight of 520kg with a complete, displaced, closed, comminuted fracture of the first phalanx of the right forelimb after he came out 5/5 lame off the race track.
- You recommend to the owner to authorise a human euthanasia at the racetrack
- After immobilising the leg in a splinted Robert Jones bandage you refer the horse to the nearest referral centre prescribing internal fixation of the fracture with double plating & lag screws
- After immobilising the leg in a splinted Robert Jones bandage you refer the horse & recommend transporting him in an open space large truck
- After immobilising the leg in a splinted Robert Jones bandage you refer the horse & recommend transporting him in a float with the partitions & with the rear legs facing the trailers’ front side
- After immobilising the leg in a splinted Robert Jones bandage you refer the horse & recommend transporting him in a float with the partitions & with the rear legs facing the trailers’ front side
Please indicate the correct statement about what would be considered a negative response to diagnostic analgesia (both palmar digital nerves (lateral & medial) in the left front limb are blocked) in a horse with a left front lameness.
- The left front lameness can no longer be seen after the nerve block
- The left front lameness becomes more evident after the nerve block
- The left front lameness goes away after the nerve block & the horse now shows a right front lameness
- The left front lameness markedly improves after the nerve block
- The left front lameness becomes more evident after the nerve block
Which of the following procedures would most specifically localise pain to the fetlock joint?
- Metacarpo-phalangeal joint block
- Abaxial sesamoid nerve block
- Carpo-metacarpal joint block
- Low four point (volar) nerve block
- Metacarpo-phalangeal joint block
A 3 year old thoroughbred racehorse filly has just returned from an intense work-out & is exhibiting signs of colic (pawing, biting at her sides). The filly is anxious & sweating. Palpation of the hindlimb musculature reveals a painful response. What is the most appropriate initial therapy indicated for this horse?
- Cool the horse with iced water
- Fluid therapy (IV or enteral)
- NSAIDs administration (IV)
- Buscopan administration (IV)
- Fluid therapy (IV or enteral)
A horse developed acute neurologic signs consistent with spinal ataxia after falling over during a competition. The horse has normal mentation, normal cranial nerve examination & is showing signs of ataxia & proprioceptive deficits on all four limbs (more pronounced in the hindlimbs). What is the most likely region for neurolocalisation?
- Sacral
- C7-T2
- C1-C6
- Thoracolumbar
- C1-C6
Ventrolateral strabismus can be related to a deficit in which cranial nerve?
- VI abducent
- IV trochlear
- III oculomotor
- V trigeminal
- III oculomotor
Which of the following propositions is false in a case of septic arthritis?
- Local treatment is much more likely to achieve a resolution of the infection
- Without local treatment there are less chances to get a control of the infection
- Identifying the causing agent helps in defining the correct antibiotic protocol
- Without arthroscopic joint lavage the sepsis has no chances to be controlled
- Without arthroscopic joint lavage the sepsis has no chances to be controlled
Please indicate the correct statement about osteochondrosis in horses.
- The proximal interphalangeal joint is the most commonly affected joint
- Despite the age of the horses, lesions always progress (get larger) or stay the same overtime
- It can be asymptomatic & diagnosed incidentally when the horse is radiographed for sale or any other reason
- It is rarely bilateral, so radiographing the contralateral joint is not recommended unless there are external signs of bilateral involvement (e.g. bilateral lameness, bilateral joint effusion)
- It can be asymptomatic & diagnosed incidentally when the horse is radiographed for sale or any other reason
After a training session, a thoroughbred colt presents a mild lameness & the swelling illustrated on the picture (SDFT tendinitis). On palpation, the affected area is warm & mildly painful.
- This is a desmitis of the suspensory ligament (M. interosseous) & the horse will need to rest 7 to 8 months
- This is a desmitis of the palmar annular ligament & the horse needs to rest 4 to 6 months
- This is a tendinitis of the superficial digital flexor tendon & the horse needs to rest 4 to 6 month
- This is a digital flexor tendon sheath tenosynovitis & the horse should recover in 6 to 8 weeks
- This is a tendinitis of the superficial digital flexor tendon & the horse needs to rest 4 to 6 month
Which of the following statements about foot problems in horses is most correct?
- Thrush is uncommon & in almost all cases causes severe lameness
- Solar penetrating puncture wounds need to be worked up using ultrasonography
- Navicular disease is more commonly seen in older horses (>10 years old) & frequently affects both front feet
- Foot abscesses typically causes severe lameness which markedly improves within 24 hours with or without treatment
- Navicular disease is more commonly seen in older horses (>10 years old) & frequently affects both front feet
Which of the following is the most correct statement regarding the tendon ultrasound below?
- Effective treatment options include platelet rich plasma (PRP) & stem cell therapy
- The scan shows a core lesion within the Deep Digital Flexor Tendon (DDFT)
- Once appropriately treated, a full recovery can be expected with a low rate of re-injury
- A CT scan of the tendon would have been the diagnostic gold standard & revealed the full extent of the lesion
- Effective treatment options include platelet rich plasma (PRP) & stem cell therapy
Please indicate the option with the correct names of the anatomical structures indicated by the tip of each arrow in the images above.
1 = metacarpo-phalangeal joint, 2 = proximal sesamoid bone, 3 = suspensory ligament, 4 = distal sesamoidean ligament, 5 = 3rd metacarpal bone
Which of the following is the most important complication to be ruled out when assessing the puncture wound of the sole shown in the image below? (Picture of nail just next to frog)
- Laminitis
- Foot abscess
- Septic navicular bursitis & or distal inter-phalangeal joint
- Pedal osteitis
- Sub solar bruise
- Septic navicular bursitis & or distal inter-phalangeal joint
A horse is presented with a laceration to the distal limb. There was obvious leakage of fluid through the wound when the distal interphalangeal joint was injected with sterile isotonic electrolyte solution under pressure (as shown in the picture). Which of the following statements is most correct?
- Daily joint lavage with a powerful antiseptic would likely reduce the risk of osteoarthritis & permanent lameness
- Prolonged systemic administration of broad spectrum antibiotics (e.g. amikacin & penicillin) would be enough to eliminate the risk of osteoarthritis & permanent lameness
- Enrofloxacin would be a good antimicrobial choice for intra-articular administration in order to reduce the risk of osteoarthritis & permanent lameness
- Regional limb perfusion with gentamicin would be a relatively inexpensive treatment to reduce the risk of osteoarthritis & permanent lameness
- Regional limb perfusion with gentamicin would be a relatively inexpensive treatment to reduce the risk of osteoarthritis & permanent lameness
The dorsal 45 degree proximal distal oblique radiograph of the foot highlights:
- The distal border of the navicular bone
- The distal interphalangeal joint…
- The proximal margin of the navicular bone
- The proximal margin of the navicular bone
Which standard radiographic projection of the tarsus highlights the most common site of osteoarthritis of the distal intertarsal & tarsometatarsal joints?
- DP
- DMPLO
- DLPMO
- LM
- DLPMO
This projection of the tarsus is most useful for examination of?
The distal intermediate ridge of the tibia & the lateral trochlear ridge of the talus
When ruling out synovial involvement after a deep heel bulb laceration, which of the following diagnostic imaging techniques would be most appropriate?
Contrast radiography
When is cryotherapy used as a treatment for laminitis?
- During the acute phase to maintain the lamellar temperature below 10 degrees for at least 48 hours
- During the chronic phase to maintain the lamellar temperature below 0 degrees for at least 48 hours
- For chronic endocrinopathic laminitis with a goal of maintaining the lamellar temperature below 10 degrees for at least 48 hours
- During the acute phase to maintain the lamellar temperature below 10 degrees for at least 48 hours
Choose the best definitive diagnostic test for a horse with suspected polysaccharide storage myopathy-1 (PSSM-1).
- Serum CK & AST concentrations, 4 to 6 hours after 15 min of exercise
- Genetic test for the GYS1 variant on hair or blood samples
- Genetic test for the GYS1 variant on hair or blood samples
Which of the following describes upper motor neuron (UMN) & lower motor neuron (LMN) deficits most accurately?
UMN = spasticity, normal to increased…
What is the best treatment for a horse with cranial trauma (traumatic brain injury)?
- Hypertonic saline IV
- Systemic antimicrobials IV
- Hypertonic saline IV
What is the most likely diagnosis of a horse with protrusion of the third eyelid, a “saw horse stance” & elevated tail head?
Tetanus
A 3 year old thoroughbred race horse filly has just returned from an intense work-out & is exhibiting signs of colic (pawing, biting at her sides). The filly is anxious & sweating. Palpation of muscle groups of her hind limbs reveals a painful response. What is the most important initial therapy indicated for this horse?
Fluid therapy (IV or oral)
