FEMURAL FRACTURES: 60 Flashcards
classification of the different types of proximal femural fractures
intracapsular:
-epiphyseal
-physeal
-subcapital
-transcervical
extracapsular:
-basilar neck
-intertrochanteric
-subtrochanteric
Classification of the different types of distal femural fractures
-supracondylar
-physeal
-condylar
-unycondylar
-bicondylar
is the fovea capitis covered by hyaline cartilage?
No
Femural neck angle of anteversion and inclination
Inclination: 130-245°
anteversion: 27-32°
Name the 3 protuberances of the proximal femur and muscles attaches to them
A) greater throcanter: middle+deep gluteal + piriformis
B) lesser throcanter: iliopsoas
C) third throcanter: superficial gluteal
Throcanteric fossa: internal + external obturator + gemelli
Arterial network to the proximal femur:
1) extraosseus
2) intraosseous
3) intracapsular
from extraosseous –> both intraosseous and intracapsular
describe in sequence from extracapsular to intracapsular arteries
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
the artery of the ligament of the head of the femur contributes to arterial vascular supply to epiphysis and proximal neck. T or F
F, only in cats (reason for probably less avascular necrosis)
how many surgical approaches exists for proximal femur?
1) cranio lateral
2) gorman approach (osteotomy greater tubercle)
3) dorsal approach with tenotomy gluteal (only joung patients!!)
name one uncommon but possible associated trauma to slipped cap
throcanteric physis separation (11-15%)
age restriction for gluteal tenotomy for dorsal prox femural approach
max 3-5 MO
there is a statistical significative association between pin number and femural neck resorption. T or F
F
A third pin for slipped cap helps with rigidity?
yes, the construct is 29% stronger
parallel vs divergent pins: Pros and Cons
Parallel > Divergent: biological+mechanical factors
BIO
-allow continued physeal growth
MECH
-forces distributed equally amongst pins
-dynamic compression fracture
how much could pin be advanced in slipped cap?
to controlateral apiphysis measurements
-80% center
-65% excentrically
Signalment in capital physeal displasia
cats>dogs
young, overweight, castrated, male
cervical fracture are more common in dogs or cats?
cats (3 to 5 times more prevalent). in dogs capitaly physis is more common
premature closure of the throcanteric physis does not led to femural length discrepancies. T or F
T
premature closure of the throcanteric physis does not led to cervical angle alteration. T or F
F. minimal, but up to 5 degree increase in both anteversion and inclination
reported rates of femural Neck resorption after open reduction and fixation of prox femural neck/physis fractures
70%
common and uncommon complication following fixation of proximal femural fractures
-premature physeal closure
-resorption of the femural neck
-inadequate reduction and stabilization
-osteoarthritis
less common
-implant failure
-implant migration
-non union
-sciatic neurapraxia
-infection
Greater dysplasia and associated degenerative changes are expected in dogs younger or older than 4 to 6 months of age with proximal femural fractures?
- 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
name 3 cases in wich primary fractire fixation should be not attempted
1) preexisting dysplasa/OA
2) Comminution head/neck
3) chronic fractures
in comminuted fragments the main blood supply arise from the medullary arteries. T or F
F: only periosteal blood supply
intramedullary rod can be safely used in immature animals. T or F
False, can lead to prox femural deformity
most common long bone affected by non union and osteomyelitis
femur
Predisposing factors to the development of contracture of the quadriceps femoris muscle
1)skeletally immature animals
2)exuberant bony callus
3)extended coaptation
4)muscular trauma
5)infection
What breed is predisposed to supracondylar fractires and why?
chondrodystrophic, because of the elongated and caudally oriented distal epiphysis
Supracondylar fractures are more common than condylar fractures. T or F
F: only 6% of all femural fractures and 30% of distal femural fractures.
Use of conventional plates for supracondylar fractures. Technique?
Overreduction of the distal segment cranially in the saggital plane
complications associated with supracondylar fractures
(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
most common Salter Harris distal femural fracture in dogs and cats
Dogs: type 2, usually fracture propagate proximally in caudal portion of the metaphysis.
Cats: type 1
the crossover point when using kirschner wires for distal physeal fracture should be …….. to the fracture site
proximal
pinning in condrodistrophic breeds. CROSS or RUSH?
only cross due to steeper angle between condyles and diaphysis
in unicondylar fractures wich condyle is more commonly affected?
Medial. opposite than humerus!!
Types of constructs can be devised to adequately stabilize distal femural fractures:
(1) interfragmentary screws (or Kirschner wires) alone
(2) interfragmentary screws and intramedullary or cross-pins
(3) interfragmentary screws combined with a buttress plate
