Chapter 6: Lower extremities (TIB FIB, KNEE, FEMUR) Flashcards
For an AP Tib Fib, how to do you determine rotation
Determine rotation by evaluating the relationship of the fibula to the tibia
in an AP TIB FIB, when the leg is laterally (externally) rotated, how does the fibula shift and what does it obscure?
the fibula shifts toward and eventually beneath the tibia obscuring the medial mortise
-decrease space between the tib/fib
in an AP TIB FIB, when the leg is medially (internally) rotated, how is the fibula
the head of the fibula draws from beneath the tibia
distal fibula is situated too far posterior on the tibia and the fibular head is demonstrated free of the tibial superimposition
External rotation of a lateral tib fib
patella too close to table/ heel elevated
distal fibula is too far anterior on the tibia and the fibular head and neck and possibly the mid-shaft is superimposed by the tibia
internal rotation of the lateral tib fib
knee too far from table
in a external rotation of the lateral tib fib when the distal fibula is situated too far posterior on the tibia , how is the fibular head
fibular head is demonstrated free of the tibial superimposition
in a internal rotation of the lateral tib fib, when the distal fibula is too far anterior on the tibia how is the fibular head and neck
the fibular head and neck and possibly the midshaft is superimposed by the tibia
what is in profile in a AP knee
medial and lateral femoral epicondyles
how are the femoral condyles in an AP knee
femoral condyles are symmetrical
how is the intercondylar eminence in an AP knee
Intercondylar eminence is centered within the intercondylar fossa
how is the tibia in an AP knee
tibia is superimposed over ¼ inch of the fibular head
how much is the tibia superimposed over the fibular head
Tibia is superimposed over ¼ inch of the fibular head
in an ap knee, if the knee is internally rotated, how does the lateral femoral condyle appear?
the lateral femoral condyle appears larger (farther away) than the medial condyle
in an ap knee, when there is internal rotation how is the tibia superimposed
Tibia is superimposed over less than ¼ inch of the fibular head
when there is too much internal rotation of the knee, what is not in profile anymore
the epicondyles
how do you determine the CR for AP knee
determine by degree of thickness of buttocks and thigh
For an AP TIB FIB, what is usually superimposed
-head of fibula should be superimposed over tibia
-lateral malleolus should be superimposed
what rotation happens more often of the tib fib
external rotation
for an ap knee, how much of a degree should you put on an individual that has 25 cm and above measurements
5 degrees cephalic
for an ap knee, how much of an angle should you put on an individual that measures between 19 and 24 cm
perp
for an ap knee, how much should you angle for an individual that has measurements of 18 cm and below
5 degrees caudal
for an ap knee. how was the angle if the fibular head is foreshortened and more than 1/2 inch distal to the tibial plateau
the cephalad angle was too great
for an ap knee, if the cephalad angle was too great how is the fibular head
foreshortened and more than 1/2 inch distal to the tibial plateau
for an ap knee, if the fibular head is elongated and less than 1/2 inch distal to the tibial plateau how was the angle
the caudal angle was too great
if the caudad angle was too great in an ap knee, how is the fibular head
elongated and less 1/2 inch distal to the tibial plateau
how much should the knee be rotated in an internal medial oblique knee
45 degrees
what is the main reason for an internal medial oblique knee
- to free fibular head of superimposition
- to see joint space between tib/fib
what is in profile in the internal medial oblique knee
lateral femoral condyle is visible in profile
how much is the degree of rotation for the external oblique knee ?
45 degrees
what is superimposed by the tibia in the external oblique knee ?
fibular head, neck and shaft
what part of the tibia is aligned with the fibular head
Fibular head is aligned with the anterior edge of the tibia
what is in profile in the external oblique knee
medial condyle
CR for AP knee
CR paralell to joint space
in an ap knee, if there is internal rotation, what appears larger
lateral condyle appears larger because it is farther from the IR
how many degrees should the knee be flexed for a lateral knee
20-30 degrees
what is superimposed in the lateral knee
medial and lateral femoral condyles (this will keep the knee joints space open)
what joint space is open in lateral knee
knee joint
what is the CR for lateral knee
5-7 degree cephalic
what do you do to keep the femoral condyles superimposed
add a 5-7 degree angle
this condyle is very smooth
lateral condyle
which condyle has the bony tubercle
medial condyle
what is the bony tubercle called that is on the medial condyle
adductor tubercle
where is the adductor tubercle located on the medial condyle?
located posteriorly and superiorly to the medial condyle
which condyle sits lower than the other
medial condyle sits lower than the lateral condyle
determining lateral and medial condyle:
if the cephalic angulation is needed how is the medial condyle
medial condyle is distal
if the medial condyle is distal, how is the angulation
cephalic angulation is needed
if the medial condyle is proximal , how is the angle
excessive cephalic angulation was used
if medial condyle is situated posteriorly in a lateral knee , how was the patella
patella was positioned too far from the IR (leg internally rotated)
in a lateral knee, if the medial condyle is situated too anteriorly, how was the patella positioned
the patella was too close to the IR (leg externally rotated)
in a lateral knee, if the medial condyle is anterior, how is the lateral condyle
more posterior
How is the pt positoned in a holmblad method
- resting on knees
-pt leans 70 degrees from ir
what is the CR for holmblad method
Cr perp to the tib fib
what is in profile in the holmblad method
medial and lateral surfaces of the intercondylar femoral epicondyles
what is the main reason for holmblad method
-to see medial and lateral surfaces of the intercondylar fossa
-condyles in profile
how should the foot be placed in the holmblad method
The foot should be placed with the long axis perpendicular to the imaging table
medial and lateral aspects of intercondylar fossa are not superimposed and the patella is rotated laterally
(holmblad method)
heel rotated internally
patella is demonstrated medially and the tibia is demonstrated without fibular head superimposition
holmblad method
heel rotated externally
in holmblad method, if the heel is rotated medially how is the patella
placing patella laterally
when the heel is out to the lateral in a holmblad method, how is patella
patella is demonstrated medially
fibular head without superimposition
if patella apex is demonstrated with in the intercondylar foss how was the knee ?
knee was overflexed
if the patella is demonstrated laterally and proximal, how was the knee
knee was underflexed
What type of projection is the beclere method
ap axial projection
how should the leg be flexed for the beclere method
flexed long axis of femur 60 degrees
how is the cr for beclere method
cr perp to lower leg
what is in profile in an ap femur
Medial and lateral femoral epicondyles are in profile
how are the femoral condyles in an ap femur
symmetrical in shape
how is the the tibia superimposed in an ap femur
tibia is superimposed over 1/4 inch of the fibular head
how is the foot rotated in an ap femur
foot internally rotated 15-20 degrees
what should not be seen or baraley seen in an ap femur
lesser trochanter (should not be in profile)
what does rotating the foot internally do to the femoral neck
puts the neck of femur parallel to ir
fibular head more than 1/4 inch over tibia
fibula rolled under tibia
what is the rotation of the leg in the femur
externally rotated
femoral neck looks foreshortened
lesser trochanter in profile
how is the leg rotated in the femur xray
leg externally rotated
what is in profile in a lateral femur
lesser trochanter
how is the head and neck in a lateral femur
superimposed on greater trochanter
what is aligned in a lateral femur
Anterior and posterior margins of the medial and lateral femoral condyles are aligned
how is the fibular head in lateral femur
Portion of the fibular head beneath the tibia
