LEC 24 - SA Extremities

Question 1

What is the general rule for determining hip dysplasia?

Answer 1

50% rule - if the head of the femur is covered by 50% of the acetabulum

Question 2

How can you tell in a hip xray whether or not it is straight?

Answer 2

Oburator foramen equal sizes

Question 3

How are the two major positional goals in hip x-rays?

Answer 3

Patella over femoral condyle and femurs parallel

Question 4

What abnormalities could occur at the coxofemoral joint?

Answer 4

Hip dysplasia, luxation, etc.

Question 5

What side of the hips sees the highest occurence of luxation?

Answer 5

Left

Question 6

What secondary changes do you see with hip dysplasia besides luxation?

Answer 6

Joint capusle laxity and femoral ligament stretch. Once chronic can cause DJD and osteoarthritis.

Question 7

What is a common fracture that occurs at the femoral head?

Answer 7

Capital physeal fracture

Question 8

Where is captial physeal fractures most commonly seen?

Answer 8

Young, male cats

Question 9

What is the general appearance of a healthy stifle?

Answer 9

Fat pad present, joint capsule within joint, condyles should be superimposed, and patella should be a normal “D” shape

Question 10

What is a salter-harris fracture?

Answer 10

Physis hasn’t closed yet. Fracture then occurs at this weak point of the bone. Prevents further growth of the bone.

Question 11

How do fractures heal?

Answer 11

Callus develops from outside, in. Leads to secondary healing process.

Question 12

How do you know the difference between secondary and primary bone healing?

Answer 12

No callus is formed with primary bone healing

Question 13

What three places might a bone tumor occur that would suggest it is a primary bone tumor?

Answer 13

Proximal humerus, distal femur, and distal tibia

Question 14

If bone lysis is noted on x-ray what are your two main differentials?

Answer 14

Cancer or infection

Question 15

What is a sign something is a bone infection not cancer?

Answer 15

infections look more proliferative rather then destructive

Question 16

What is most likely the cause of osteomyelitis in multiple regions?

Answer 16

Systemic infections

Question 17

What does a bone cyst look like on x-ray?

Answer 17

Cortex thinning, nice neat capsule with distinct borders.

Question 18

Where do secondary bone tumors begin?

Answer 18

At the nutrient foramen

Question 19

What is a cancer that occurs in the joint capsule?

Answer 19

Synovial cell sarcoma

Question 20

What is the radiographic description of Synovial cell sarcoma?

Answer 20

Will cross the joint on both sides

Question 21

How do you know if something is synovial cell sarcoma rather then osteosarcoma?

Answer 21

OSA does not cross the joint while SCC does.

Question 22

What is the general appearance of panosteitis on x-ray?

Answer 22

Will occur in a young dog. Medullary canal will appear to be more lucent

Question 23

What are three common ways that you see elbow dyplasia?

Answer 23

UAP, Chronic DJD, and elbow incongruity

Question 24

How might a dog present with elbow dysplasia?

Answer 24

Weight will be distributed more on the medial side.

Question 25

Where do you first see changes in the elbow with elbow dysplasia?

Answer 25

Medial (ulnar notch) rather than lateral (radial head)

Question 26

How much of bone growth does Ulnar physes account for?

Answer 26

85%

Question 27

How much of bone growth occurs at each end of the bone?

Answer 27

50%/50%

Question 28

What ligament is commonly torn when carpal luxation is seen on radiographs?

Answer 28

Palmar ligament

Question 29

Describe Varus -

Answer 29

Deviates medially, increased lateral growth, decreased medial growth

Question 30

Describe Valgus -

Answer 30

Deviates laterally, increased medial growth, decreased lateral growth

Question 31

What causes legg-calve-perth’s disease?

Answer 31

Decrease blood flow to femur leading to bone atrophy

Question 32

How might a dog present with a malunion fracture?

Answer 32

Not really that painful walk further up on toes