FEMURAL FRACTURES: 60

Question 1

classification of the different types of proximal femural fractures

Answer 1

intracapsular:
-epiphyseal
-physeal
-subcapital
-transcervical

extracapsular:
-basilar neck
-intertrochanteric
-subtrochanteric

Question 2

Classification of the different types of distal femural fractures

Answer 2

-supracondylar
-physeal
-condylar
-unycondylar
-bicondylar

Question 3

is the fovea capitis covered by hyaline cartilage?

Answer 3

No

Question 4

Femural neck angle of anteversion and inclination

Answer 4

Inclination: 130-245°
anteversion: 27-32°

Question 5

Name the 3 protuberances of the proximal femur and muscles attaches to them

Answer 5

A) greater throcanter: middle+deep gluteal + piriformis
B) lesser throcanter: iliopsoas
C) third throcanter: superficial gluteal

Throcanteric fossa: internal + external obturator + gemelli

Question 6

Arterial network to the proximal femur:

Answer 6

1) extraosseus
2) intraosseous
3) intracapsular

from extraosseous –> both intraosseous and intracapsular

Question 7

describe in sequence from extracapsular to intracapsular arteries

Answer 7

1) medial circumflex femural+lateral circumflex femural+caudal gluteal ->
2) form extra capsular ring
3) penetrate joint capsule, create near physis intracapsular vascular ring
4) penetrate physis, create intraosseus arcuate network

Question 8

the artery of the ligament of the head of the femur contributes to arterial vascular supply to epiphysis and proximal neck. T or F

Answer 8

F, only in cats (reason for probably less avascular necrosis)

Question 9

how many surgical approaches exists for proximal femur?

Answer 9

1) cranio lateral
2) gorman approach (osteotomy greater tubercle)
3) dorsal approach with tenotomy gluteal (only joung patients!!)

Question 10

name one uncommon but possible associated trauma to slipped cap

Answer 10

throcanteric physis separation (11-15%)

Question 11

age restriction for gluteal tenotomy for dorsal prox femural approach

Answer 11

max 3-5 MO

Question 12

there is a statistical significative association between pin number and femural neck resorption. T or F

Answer 12

F

Question 13

A third pin for slipped cap helps with rigidity?

Answer 13

yes, the construct is 29% stronger

Question 14

parallel vs divergent pins: Pros and Cons

Answer 14

Parallel > Divergent: biological+mechanical factors

BIO
-allow continued physeal growth

MECH
-forces distributed equally amongst pins
-dynamic compression fracture

Question 15

how much could pin be advanced in slipped cap?

Answer 15

to controlateral apiphysis measurements

-80% center
-65% excentrically

Question 16

Signalment in capital physeal displasia

Answer 16

cats>dogs
young, overweight, castrated, male

Question 17

cervical fracture are more common in dogs or cats?

Answer 17

cats (3 to 5 times more prevalent). in dogs capitaly physis is more common

Question 18

premature closure of the throcanteric physis does not led to femural length discrepancies. T or F

Answer 18

T

Question 19

premature closure of the throcanteric physis does not led to cervical angle alteration. T or F

Answer 19

F. minimal, but up to 5 degree increase in both anteversion and inclination

Question 20

reported rates of femural Neck resorption after open reduction and fixation of prox femural neck/physis fractures

Answer 20

70%

Question 21

common and uncommon complication following fixation of proximal femural fractures

Answer 21

-premature physeal closure
-resorption of the femural neck
-inadequate reduction and stabilization
-osteoarthritis

less common
-implant failure
-implant migration
-non union
-sciatic neurapraxia
-infection

Question 22

Greater dysplasia and associated degenerative changes are expected in dogs younger or older than 4 to 6 months of age with proximal femural fractures?

Answer 22

• medium-sized dogs, 95% of capital physeal growth is complete by 7 months of age
• whereas only 80% of growth is complete at 5 months of age.
  Therefore, more severe OA is expected at younger ages

Question 23

name 3 cases in wich primary fractire fixation should be not attempted

Answer 23

1) preexisting dysplasa/OA
2) Comminution head/neck
3) chronic fractures

Question 24

in comminuted fragments the main blood supply arise from the medullary arteries. T or F

Answer 24

F: only periosteal blood supply

Question 25

intramedullary rod can be safely used in immature animals. T or F

Answer 25

False, can lead to prox femural deformity

Question 26

most common long bone affected by non union and osteomyelitis

Answer 26

femur

Question 27

Predisposing factors to the development of contracture of the quadriceps femoris muscle

Answer 27

1)skeletally immature animals
2)exuberant bony callus
3)extended coaptation
4)muscular trauma
5)infection

Question 28

What breed is predisposed to supracondylar fractires and why?

Answer 28

chondrodystrophic, because of the elongated and caudally oriented distal epiphysis

Question 29

Supracondylar fractures are more common than condylar fractures. T or F

Answer 29

F: only 6% of all femural fractures and 30% of distal femural fractures.

Question 30

Use of conventional plates for supracondylar fractures. Technique?

Answer 30

Overreduction of the distal segment cranially in the saggital plane

Question 31

complications associated with supracondylar fractures

Answer 31

(1) osteoarthritis
(2) implant-associated lameness due to interference with the patella
(3) secondary fracture
(4) malunion
(5) patellar luxation
(6) contracture of the quadriceps femoris muscle

Question 32

most common Salter Harris distal femural fracture in dogs and cats

Answer 32

Dogs: type 2, usually fracture propagate proximally in caudal portion of the metaphysis.
Cats: type 1

Question 33

the crossover point when using kirschner wires for distal physeal fracture should be …….. to the fracture site

Answer 33

proximal

Question 34

pinning in condrodistrophic breeds. CROSS or RUSH?

Answer 34

only cross due to steeper angle between condyles and diaphysis

Question 35

in unicondylar fractures wich condyle is more commonly affected?

Answer 35

Medial. opposite than humerus!!

Question 36

Types of constructs can be devised to adequately stabilize distal femural fractures:

Answer 36

(1) interfragmentary screws (or Kirschner wires) alone
(2) interfragmentary screws and intramedullary or cross-pins
(3) interfragmentary screws combined with a buttress plate