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Flashcards in Stifle Deck (37)
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1
Q

Describe the attachments of the cranial cruciate ligament

A

medial side of the lateral femoral condyle, to the cranial intercondylar tibia

2
Q

Describe the attachments of the caudal cruciate ligament

A

medial femoral condyle to the popliteal notch of the tibia

3
Q

What is the function of the cranial cruciate ligament?

A

to prevent cranial tibial translation/thrust

4
Q

What happens in a cranial cruciate avulsion, and how is it treated?

A
  • small piece of bone with ligament breaks off

- repaired with lag screw or K-wire

5
Q

What can cause acute traumatic rupture of the cranial cruciate ligament?
Describe the injury

A
  • excessive limb loading or hyperextension
  • painful, non-weight bearing lameness, and joint instability
  • “mop end” tear of ligament
6
Q

What are the predisposing factors for progressive degeneration of cranial cruciate ligament?

A
  • increased tibial plateau angle
  • obesity
  • abnormal confirmation
  • rottweilers, labs
  • femals
  • sterilized
7
Q

Explain the biomechanics of cranial tibial thrust

A
  • downward force acts on stifle
  • upward force from quadriceps pulls on patella
  • creates a shear at stifle
8
Q

What can be found on PE of a dog with a cranial cruciate injury?

A
  • stifle pain on extension and flexion
  • crepitus, with “click” if concurrent meniscal tear
  • medial buttress (fibrosis)
  • quadriceps muscle atrophy
  • joint effusion on med and lat aspects of patellar ligament
  • dog sits with legs out to the side
9
Q

Describe the components of the cranial cruciate ligament

A
  • craniomedial band is taut in flexion and extension

- caudolateral band is taut in extension

10
Q

What is the cranial drawer test?

A
  • confirms joint instability by creating cranial tibial translation
11
Q

What is meant by “puppy drawer”?

A
  • puppies < 6 months will have some cranial tibial translation
  • limited to 4-5 mm
12
Q

What is the tibial compression test?

A
  • creates stifle joint compression and results in cranial tibial thrust
  • stimulates gastrocnemius tension
13
Q

What can be found on radiograph of an animal with cranial cruciate disease?

A

infrapatellar fat pad may be caudally displaced or contain osteophytes

14
Q

What is the gold standard for joint evaluation?

A

arthroscopy

15
Q

What are the functions of the menisci?

A
  • load distribution
  • shock absorption
  • joint intability
16
Q

Which meniscus is most commonly affected?

A

medial meniscus

17
Q

Why are the menisci prone to injury concurrent with a cranial cruciate injury?

A
  • when the cruciate ruptures, the menisci acts as a joint stabilizer
  • acts as a wedge to prevent further subluxation
18
Q

What is the most common type of meniscal tear?

A

bucket handle tear

- displaced vertically

19
Q

What are the treatment options for a meniscal tear?

A
  • primary repair rarely done
  • partial meniscectomy
  • meniscal release
20
Q

Describe the intra-articular reconstruction procedure

A
  • utilizes fascia lata or patellar ligament
  • passed through joint at lateral femoral condyle
  • poor success rate
21
Q

Which procedures are used to treat cranial cruciate ligament rupture/disease?

A
  • intra-articular reconstruction
  • lateral suture stabilization
  • tightrope
  • tibial plateau leveling osteotomy
  • tibial tuberosity advancement
22
Q

Describe the lateral suture stabilization technique

A
  • place suture around lateral fabella
  • pass suture through hole drilled in tibial tuberosity
  • position limb at 110 degrees flexion and tighten suture until cranial drawer is eliminated
23
Q

What is the prognosis for lateral suture stabilization?

A
  • 85% improvement

- rehabilitation very important

24
Q

Describe the tightrope procedure

A
  • extracapsular technique
  • counteracts cranial tibial thrust
  • holes drilled through distal femur and proximal tibia
  • tensioner to control desired tension
25
Q

Describe the tibial plateau leveling osteotomy

A
  • alter tibial plateau angle to eliminate the shearing force

- Rotate proximal tibial fragment so the plateau is perpendicular to the weight-bearing axis

26
Q

Describe the tibial tuberosity advancement procedure

A
  • alter patellar angle perpendicular to plateau to neutralize shear forces
27
Q

Which skeletal abnormalities can induce medial patellar luxation?

A
  • coxa vera: decreased angle of inclination

- femoral retroversion

28
Q

What are the conformational abnormalities associated with medial patellar luxation?

A
  • distal femoral varus
  • genuvarum
  • shallow trochlear groove
29
Q

Describe a grade 1 medial patellar luxation

A
  • no lameness
  • patella can be manually luxated
  • patella returns to groove after release
30
Q

Describe a grade 2 medial patellar luxation

A
  • occasional spontaneous luxation
  • intermittent lameness
  • once luxated, has to be manually reduced
31
Q

Describe a grade 3 medial patellar luxation

A
  • patella is continuously luxated but can be manually reduced
  • more severe lameness
32
Q

Describe a grade 4 medial patellar luxation

A
  • patella fixed in luxation
  • cannot manually reduce
  • severe lameness
33
Q

Describe a trochlear sulcoplasty

A
  • remove hayline cartilage and subchondral bone

- fill in with fibrocartilage

34
Q

Describe a trochlear chondroplasty

A
  • creation of cartilage flap from subchondral bone

- for patients < 6 months

35
Q

Describe a trochlear wedge resection

A
  • wedge cut from peak of condyles
  • subchondral bone is deepened
  • wedge is replaced
36
Q

Describe a tibial tuberosity transposition

A
  • centers ligament in patellar groove
  • osteotomy of tibial tuberosity
  • shift tuberosity lateral and secure with K-wire and tension band
37
Q

What skeletal abnormalities are associated with lateral patellar luxation?

A
  • distal femoral valgus
  • lateral condylar hypoplasia
  • genuvalgum