Canine Flash Notes - Canine Stifle Problems

Question 1

what animals are most often affected by patellar luxation?

Answer 1

dogs > cats

small breeds (poodles & yorkies) &raquo_space;> large breeds

congenital > acquired

medial&raquo_space; lateral

Question 2

what are the different grades of patellar luxation?

Answer 2

1 - easily luxated, returns when released

2 - easily luxated, remains luxated

3 - permanently luxated but can be manually returned

4 - permanently luxated & can’t be manually returned

Question 3

what are the differentials that should be considered for an animal with suspected patellar luxation?

Answer 3

leg-perthes disease, traumatic ligament rupture (cranial cruciate or medial collateral ligament) meniscal injury, & coxo-femoral luxation

Question 4

what are the classic clinical signs seen in an animal with luxating patellas?

Answer 4

rear leg lameness - intermittent to carrying limb

Question 5

how are luxating patellas diagnosed?

Answer 5

palpation - extend limb & assess grade of luxation

skyline view rads in sternal recumbency - flex stifle & place animal on its knees to show the depth of the trochlear groove, patella, & joint space

Question 6

what is the conservative treatment used for animals with luxating patellas?

Answer 6

if minimal clinical signs or mature dog > 1 year old

weight reduction, controlled exercise, NSAIDS

Question 7

when is surgery indicated for an animal with luxating patellas?

Answer 7

if growth plates are open - persistent luxation indicates the need for immediate surgical correction

Question 8

what are the main surgeries used to correct luxating patellas?

Answer 8

deepening the trochlear groove - trochleoplasty to deepen the groove & chondroplasty making a cartilage flap from the trochlear groove replaced after groove is deepened

wedge recession - cut wedge out of groove, then deepen cut & replace wedge

tibial tuberosity translocation - move tibial tuberosity to the side away from the luxation

medial release of the joint capsule & muscle insertions onto patella

lateral rotation of the tibia

Question 9

what kind of trauma is required for stifle luxation? what animals is it more common in?

Answer 9

severe - rupture of cranial & caudal cruciate ligaments, medial & lateral collateral ligaments, meniscal attachments, politeus, & long digital extensors

more common in cats

Question 10

how is stifle luxation diagnosed?

Answer 10

palpation - total laxity in all directions, lateral medial, cranial caudal, & rotational instability

Question 11

how is stifle luxation treated?

Answer 11

repair medial & lateral collateral ligaments, politeus & long digital extensor mm

Question 12

what is the classic case presentation of a dog with a ruptured cranial cruciate ligament?

Answer 12

middle aged overweight dogs - usually will see deterioration of ligament on other leg within a year

young dogs - trauma

carrying limb lameness - may resolve but returns with exercise

or chronic persistent lameness (older, overweight dogs)

Question 13

how is a ruptured cranial cruciate ligament diagnosed?

Answer 13

clinical signs/history

cranial drawer sign

rads - degenerative joint disease, joint effusion, & avulsion fx

Question 14

how are cruciate ligament ruptures in small dogs treated?

Answer 14

rest for 3-4 months

Question 15

what surgical correction is used for ruptured cruciate ligaments? what is the post-op treatment?

Answer 15

TPLO

TTA

restrict exercise to leash only, no stairs for 4-5 months

Question 16

what is the cranial drawer sign?

Answer 16

hold distal femur & proximal tibia with 2 hands

push tibia cranially - if you see cranial movement/caudal movement, ruptured

Question 17

how is tibial compression performed?

Answer 17

hold femur motionless with one hand & put a finger on the tibial tuberosity

flex the hock

if tibia moves cranially - rupture