Large Animal Surgery

1
Large Animal Surgery

• Angular limb deformities

2
What subset of the population most commonly gets
flexor tendon laxity

• Premature foals

3
What is the pathogenesis of flexor tendon laxity

• Uterine malposition
• Premature parturition
• Flaccidity of flexor muscles
• Misc mare factors (infections, nutrition etc)

4
What is the treatment for flexor tendon laxity

• Controlled exercise is usually sufficient
• Also swimming or a glue on shoe with palmar
  extension in severe cases

5
What is the prognosis for flexor tendon laxity

• Good

6
How long does it usually take for full recovery

• Full recovery in about 2 weeks

7
Why do you not cast or splint foals with flexor
tendon laxity

• Weakening of the soft tissue supporting
  structures which causes articular laxity upon
  cast removal

8
Following cast removal how long should return to
exercise take

• As long as the limb was immobilized

9
What does an injury to the DDF look like

• Toe is pointing up

10
What is the treatment for DDF laceration or laxity

• Suture the tendon together
• Orthopedic shoe with raised and extended heal

11
What is club foot

• Flexural deformity of the coffin joint

12
Where and in what age group is club foot most
common

• Young animals
• In the thoracic limb

13
What is the medical treatment for flexural
deformity

• Controlled exercise
• Lower nutrition plane
• Physical therapy
• Bandage splints or casts
• Oxytet 3 grams
• Phenylbutazone
• Corrective shoeing
• Hoof trimming

14
How does oxytet help

• Binds the calcium relaxing the muscle

15
Do cows have a check ligament

• No

16
What is the treatment for a calf with a
contracted tendon

• Physical therapy and stretching
• Can glue a shoe on with an extended toe

17
What is the surgical therapy for a contracted
tendon in cattle

• Cut SDF, DDF and maybe the joint capsule

18
If you cut the SDF or DDF what else must you do

• Cast or splint

19
What happens after the cast is removed

• Tendon laxity

20
What is the prognosis for return to function

• Guarded to poor

21
What is your diagnosis

• Chronic club foot

22
How do you differentiate this from laminitis

• P3 is parallel to the hoof wall which would not
  be the case if this horse had laminitis

23
How do you trim the hoof to overcome club foot

• Trim the heal
• Leave the toe long

24
What else can be done besides the extended toe

• Use padding between the shoe and the hoof
• To raise the toe and stretch the flexor tendon

25
What is the surgical treatment for club foot

• Inferior check ligament desmotomy

26
When would you do surgery for club foot

• Cases that are refractory to medical treatment

27
What may need to be the treatment in very severe
cases of club foot

• Incise the entire DDF

28
How does fetlock flexural deformity develop

• Usually acquired
• Over nutrition or decreased use of the leg due to
  pain

29
Which limb is fetlock flexural deformity most
common in

• More common in the forelimb

30
What age is fetlock and pastern flexural
deformity most commonly seen in

• Yearlings
• 8-18 months

31
What are the parameters to designate a severe
case of fetlock flexural deformity

• gt180 degree rotation

32
What may have to be done in these severe cases

• May have to cut both check ligaments and SDF

33
What is the treatment for a mild case of fetlock
flexural deformity

• Toe extensions, decrease feeding

34
What is the treatment for a moderate case of
fetlock flexural deformity

• Proximal check ligament desmotomy (maybe also
  distal check desmotomy)

35
What is the prognosis for club foot

• Good

36
What is the prognosis for flexural deformity

• Guarded

37
What prenatal factors may cause angular limb
deformities

• Periarticular laxity, hypoplasia of cuboidal
  bones, teratogenic insult, placentitis, hormonal
  nutritional imbalances

38
What postnatal factors may cause angular limb
deformities

• Unfavorable limb conformation
• Excessive growth rate
• Physeal injuries
• Continuous overloading of the physis

39
If you find an angular limb deformity what else
should you look for

• Another congenital anomaly

40
What is ill thrift syndrome in llamas

• Poor growth rates with ALD

41
What other things were found in the lab work on
these llamas

• Hypothyroidism
• Anemia
• Erythrocyte dyscrasia

42
What is the conservative treatment of ALD

• Stall rest
• Physical therapy
• Splinting/ casts

43
Describe the cast that would be used for ALD

• They do not include the foot so that the tendons
  can accept weight properly

44
If the ALD is manually reducible what are the
probable causes

• Periarticular laxity
• Hypoplasia of the cuboidal bones (early stage)

45
If the ALD is not manually reducible what are the
probable causes

• Asynchronous physeal or epiphyseal growth
• Untreated cases of cuboidal bone hypoplasia
• Diaphyseal deformities

46
When do the carpal bones ossify

• Should be ossified at birth

47
What can happen if carpal/tarsal bone hypoplasia
is not corrected

• Can result in crushed carpal bones leading to
  permanent lameness

48
Which animals tend to have hypoplasia of the
carpal/tarsal bones

• Premature, dysmature and twins

49
How do you treat hypoplasia of the carpal/tarsal
bones

• Tube cast (not including the foot or the fetlock)

50
How long does it take for ossification to be
completed

• 2-4 weeks

51
How do you know when the tube cast can be removed

• Radiograph at 14 day intervals

52
For ALD due to ligament laxity what is the
treatment

• Controlled exercise and stall rest

53
When does asymmetric physeal growth usually occur

• 2 weeks and 6 months of age

54
How severe is the deformity due to asymmetric
physeal growth

• Usually mild

55
How do you initially treat asymmetric physeal
growth

• Trim the hoof wall so the foot is level
• Small paddock rest

56
If the initial treatment is unsuccessful what is
the next step

• Surgical treatment

57
For optimal results to correct the radius or
tibia surgery should be done by what age

• 4 months

58
For optimal results to correct the
metacarpus/metatarsus surgery should be done by
what age

• 2 months

59
Why should ALD should be fixed even if there is
no carpal bone damage

• Cosmetic perspective
• DJD

60
What is peculiar about the llamas forelimbs

• Complete ulna
• Radius and ulna grow at different rates

61
What are the causes of physeal dysplasia

• Nutritional component, mechanical component,
  heritability, speculation

62
What is the treatment for non reducible deviation

• Periosteal transection and stripping

63
How does periosteal stripping help ALD

• Release of periosteal tension
• Activates bone growth

64
When does the physis of the distal radius and
ulna close

• 3.5 years of age

65
What side do you perform periosteal stripping

• Lateral side for valgus
• Medial for varus

66
What should be done post op for periosteal
stripping

• Exercise restriction

67
When would you perform an ulnar ostectomy

• With severe deformities (gt15 degrees)
• Older animals when growth is diminishing

68
T or Fyou need to be careful when performing
ulnar ostectomy to avoid overcompensation (ie
valgus goes to varus)

• False

69
What is the purpose of transphyseal bridging

• Retard growth

70
How is transphyseal bridging performed

• Screws and/or wire is placed to slow growth

71
T or Fyou need to be careful when performing
transphyseal bridging to avoid overcompensation
(ie valgus goes to varus)

• True

72
What is the most common cause of lameness in
cattle

• Sole abscess

73
Which digits support the most weight in cattle

• Rear lateral
• Front medial

74
What is the significance of this

• Digits that support more weight are predisposed
  to injury

75
How often should dairy cattle get their hooves
trimmed

• About ever 6 months

76
How do you treat a crack in the hoof wall

• Debridement and block on the good digit

77
What is a corn

• Growth between the digits (fibroma or hyperplasia)

78
What is the signalment for corns

• More common in males

79
How do you treat corns

• Trim hooves to balance them
• Sx to remove the corn

80
What is a differential for a corn

• Fibropapilloma hairy warts

81
What is the etiology of hairy warts

• Treponema

82
What is a good way of differentiating the two
pathologies

• Hairy warts are on the plantar/palmar aspect..
  not interdigital

83
How do you treat a sole abscess

• Trim hoof
• Drain pus
• Let heal by 2nd intention
• Raise the good digit with a block

84
What are the pros of amputation

• Good short term results
• Inexpensive
• Rapid
• Simple
• Rapid return to production

85
What are the pros of arthrodesis

• Good long term results

86
What are the cons of arthrodesis

• Expensive
• Time consuming
• Technically demanding
• Slow return to production

87
What are the principles of arthrodesis

• Establish drainage
• Treat infection
• Destroy articular cartilage
• Immobilize

88
What is the most important thing in performing
arthrodesis

• Must have bone-to-bone contact

89
What is the usual method of anesthesia for digit
amputation

• IV regional anesthesia

90
What angle should the incision be when doing a
digit amputation

• Very steep

91
What are the two methods of digit amputation

• Skin flap
• Open technique

92
When would you do a skin flap digit amputation

• With a non-septic defect

93
Which technique is more commonly performed

• Open technique

94
Why would you do a digit amputation

• P3 fx
• Pedal osteitis
• Luxation
• Deep sepsis of the digit
• Septic arthritis of the DIP or PIP joint

95
What is the worse cow to do an amputation on

• A large heavy bull (may never be able to get up)

96
Which digits should you never remove

• Rear lateral
• Front medial

97
What is the difference between ankylosis and
arthrosis

• Ankylosis is a natural process whereas arthrosis
  is a surgically created ankylosis

98
What is the treatment for acute septic DIJ

• Intraarticular lavage
• Systemic antibiotics

99
What is the treatment for chronic septic DIJ

• Amputation
• Facilitated ankylosis

100
What are the clinical signs of septic DIJ

• Swelling
• Draining tract
• Laceration
• Puncture wound

101
How do you diagnose septic DIJ

• PE
• Fistulogram
• Rads

102
Are cows with septic DIJ typically slightly lame
or severely lame

• Severely lame

103
What are the causes of septic arthritis

• Pododermatitis
• White line sz
• Interdigital necrobacillosis
• Interdigital puncture wound
• Periarticular wound

104
How long after inoculation of bacteria will you
start to see boney lysis

• 10-14 days

105
How do you treat septic arthritis

• Use trephine to make an arthrotomy into the
  coffin joint
• Remove the infected cartilage and bone with
  curette
• Culture the subchondral bone

106
What organisms are commonly isolated from cases
of septic arthritis

• A pyogenes
• S aureus
• E coli
• Bacteroides

107
What cases would you apply a block

• Sole abscess
• Fx of P3
• Tendon laceration
• Vertical crack
• Septic arthritis

108
How do you decrease movement after surgery

• Wire toes together
• (can use cast)

109
What is the success rate in treating septic
arthritis in cattle

• 100

110
Why is there a very bad prognosis in treating
septic arthritis of the coffin join in horses

• Often will get laminitis in the contralateral limb

111
What are the advantages of facilitated ankylosis
vs amputation

• Greater longevity
• Better locomotion
• Longer production life

112
What are the disadvantages of facilitated
ankylosis vs amputation

• More expensive
• More post op therapy
• Often slower return to production

113
When would you want to do a surgical ankylosis
instead of an amputation

• Animal of high Genetic value
• Heavy animals
• Rear lat or front med digit affected
• Pets
• Longer production life desired

114
What is high ring bone

• Osteophyte formation in the pastern

115
What is low ring bone

• Osteophyte formation in the coffin joint

116
After performing an arthrodesis when would you
want to remove the plate

• If there is a sign of infection or if the horse
  is in a cold climate

117
Is there a better success rate of arthrodesis of
the front limb or rear limb

• Rear limb
• 80 rear limb
• 60 front limb

118
If there is damage to the SDF, DDF and suspensory
ligament what can be done as treatment

• Fetlock arthrodesis

119
Why is fetlock arthrodesis a salvage procedure

• High motion joint
• Often will get laminitis of the contralateral limb

120
What is wrong with this horse

• Sickle hocks

121
What causes sickle hocks

• Wear and tear with poor conformation

122
What is wrong with this horse

• Cow hocks

123
What is bone spavin

• DJD of the distal tarsal and tarso-metatarsal
  joints

124
Which aspect of the joint is bone spavin most
pronounced

• Medial aspect

125
What is the treatment for bone spavin

• Arthrodesis
• Medical therapy
• Intraarticular injection of corticosteroids and
  adequan to facilitate natural arthrodesis,
  phenylbutazone, lots of exercise

126
What is the rate of return to soundness with
surgical arthrodesis

• 59-85