Knee

Question 1

Knee X-Ray Series

Answer 1

• Normal Series - AP and Lateral Optional Views -
• Intercondylar Fossa - AP Intercondylar, Rosenberg’s, used to assess the intercondylar fossa, femoral condyles and tibial plateaus
• Axial (Sunrise) Patella - Assess patellofemoral joint

Question 2

AP Knee

Answer 2

• Cassette - 24x30, vertical
• Positioning - Weight bearing, pt against bucky, patella is positioned parallel to bucky, might need to internally rotate foot 3-5 Non-weight bearing, pt is supine or sits comfortably with knee positioned as above.
• Stabilization - Neutral stance or lying comfortably
• Shielding - Gonad shielding/lead apron Instructions - palpate epicondyles to ensure they are at equal distance SID - 100cm
• Central Ray - 1cm inferior to patella apex
• Tube Tilt - 0
• Collimation - M-L, include soft tissues of the knee joint S-I, include the distal 1/3 femur and proximal 1/3 tibia and fibula
• kV - Children 60 and adults 70
• Marker Placement - lateral to the anatomy

Question 3

Lateral knee

Answer 3

• Cassette - 24x30, vertical
• Positioning - Weight bearing, pt against bucky in a fencer stance with affected knee against the bucky. Knee is flexed to 30 and needs to be flush with bucky. Non-weight bearing, pt is sidelying with knee positioned as above with knee against cassette.
• Stabilization - fencer stance or sidelying comfortably
• Shielding - Gonad shielding/lead apron
• Instructions - palpate epicondyles and patella to ensure no rotation. Turn head away rom
• SID - 100cm
• Central Ray - 1cm below the medial epicondyle
• Tube Tilt - 5 degree cephalad
• Collimation - M-L, include soft tissues of the knee joint S-I, include the distal 1/3 femur and proximal 1/3 tibia and fibula
• kV - Children 60 and adults 70
• Marker Placement - lateral to the anatomy

Question 4

AP Intercondylar Knee

Answer 4

• Cassette - 18x24, vertical
• Positioning - Supine on floor with knee bent to 45 and cassette placed under the knee against posteior thigh and leg.
• Stabilization - use all limbs to stablize and gonad shielding
• Shielding - Gonad shielding/lead apron, turn head away
• Instructions - stablize and turn head
• SID - 100cm
• Central Ray - 1cm below the apex of patella
• Tube Tilt - 40-45 cephalad
• Collimation - M-L, include soft tissues of the knee joint S-I, include the distal 1/3 femur and proximal 1/3 tibia and fibula
• kV - Children 60 and adults 70
• Marker Placement - lateral to the anatomy

Question 5

Rosemberg’s View Knee

Answer 5

• Cassette - 18x24 unilateral or 24x30 bilateral
• Positioning - Pt is facing the bucky, standing
• Stabilization - fencer stance or sidelying comfortably
• Shielding - Gonad shielding/lead apron
• Instructions - flex knees for femurs are at 45 to horizontal
• SID - 100cm Central Ray - mid point to popliteal crease
• Tube Tilt - 10 degree caudad to tibial plateau
• Collimation - M-L, include soft tissues of the knee joint S-I, include the distal 1/3 femur and proximal 1/3 tibia and fibula
• kV - Children 60 and adults 70
• Marker Placement - lateral to the anatomy

Question 6

Axial (Sunrise) Patella

Answer 6

• Cassette - 18x24 vertical
• Positioning - Pt is supine, sitting and knee bent to 45 with no leg rotation. Cassette is behind the leg, mid thigh and perpendicular to central ray
• Stabilization- support can be used under knee and sandbags and straps can be used on the cassette
• Shielding - Gonad shielding/lead apron
• Instructions - turn head away
• SID - 100cm
• Central Ray - apex of patella
• Tube Tilt - 10-15 cephalad in the patellofemoral joint
• Collimation - M-L, include soft tissues of the patella. S-I, include soft tissues of the patella
• kV - Children 60 and adults 70
• Marker Placement - lateral to the anatomy