knee and patella Flashcards
rotate leg ________________ for a true AP knee (until inter-epicondylar line is parallel)
internally 3-5 degrees
Rotate leg internally 3-5 degrees for a true AP knee (until _________________)
inter-epicondylar line is parallel
kVp range for knee
65-80 kVp
where do we center the CR for an AP knee?
aligned parallel with articular facets (tibial plateau)
1/2 inch distal to apex of patella
what is the CR angle for thinner patients on an AP knee?
5 degrees caudad
what is the CR angle for average patients on an AP knee?
perpendicular to IR
what is the CR angle for thicker patients on an AP knee?
5 degrees cephalic
Knee flexed ___________ for a lateral (mediolateral) knee x-ray
20-30 degrees
where is the CR aligned for a lateral recumbent lateral knee?
Angle CR 5-7 deg cephalad for lateral recumbent projection
where is the CR directed for a lateral recumbent lateral knee?
1 inch distal to medial epicondyle
for a lateral (mediolateral) knee, the femoral epicondyles are _______________ and plane of patella is _________________
directly superimposed; perpendicular to the IR
for a medial oblique knee, intercondylar line should be ___________
45 degrees to plane of IR
for a medial oblique knee, the ________ should be rotated
entire leg
for a medial oblique knee, angle the CR ________
0 degrees (perpendicular to IR)
where is the CR directed in a medial oblique knee?
0 degree angulation/perpendicular; 1/2 inch distal to apex of patella
where is the CR direct in a lateral oblique knee?
0 degree angulation/perpendicular; 1/2 inch distal to apex of patella
what is the knee flexion angle when doing a Camp Coventry x-ray?
40-50 degree flexion (with support under ankle)
what is another name for a Camp Coventry x-ray?
PA Axial “tunnel view”
what is the knee flexion angle when doing a Beclere x-ray?
40-45 degrees
where is the CR in a Camp Coventry x-ray?
Perpendicular to lower leg (40-50 degree caudad to match degree of flexion)
what is the CR angulation in a Beclere x-ray?
Perpendicular to lower leg (40-45 degree cephalad to match degree of flexion)
where is the CR directed in a Beclere x-ray?
1/3 inch distal to apex of patella
what is the CR angle in a PA patella?
perpendicular to IR
where is the CR directed in a PA patella?
mid-patella (approx. mid-popliteal crease)
what is the CR angle in a lateral patella?
perpendicular to IR
where is the CR directed in a lateral patella?
mid-patellofemoral joint
what is the knee flexion of a lateral patella?
only 5-10 degrees
