Evaluation Criteria: Tibia and Fibula to Knees

Question 1

A patient has a 20-degree angle posterior tibial plateau slope. How would you alter your standing AP and PA knee projections?

Answer 1

For AP, the angle caudad 20 degrees, and for PA use the cephalad angle of 5 degrees

Question 2

What should you see on an AP Tib/Fib?

Answer 2

• Ankle and knee joints visualized
• Proximal and distal tibiofibular joints overlapping
• Fibular midshaft free of superimposition

Question 3

What should you see on a lateral Tib/Fib?

Answer 3

• Both joints visualized
• Distal fibula over posterior 1/3 of tibia
• Slight overlap of proximal fibular head with tibia
• Separation of tibial/fibular shafts
• Possibly superimposed femoral condyles

Question 4

What should you see on an AP or PA knee?

Answer 4

• Open femorotibial joint space
• Femoral condyles symmetrical
• Slight superimposition of fibular head with tibia
• Patella superimposed on femur

Question 5

What should you see on an AP Oblique Lateral Rotation knee?

Answer 5

• Medial femoral and tibial condyles
• Tibial plateaus/Open knee joint
• Lateral border of patella not superimposed
• Fibula superimposed with lateral half of tibia

Question 6

What should you see on a Lateral Knee?

Answer 6

• Femoral condyles superimposed
• Open femorotibial joint space
• Open patellofemoral joint space
• Fibular head slightly superimposed with tibia

Question 7

What would you see if there was under rotation of a lateral knee?

Answer 7

• Locate adductor tubercle of medial condyle
• More superimposition of tibia and fibula

Question 8

What would you see if there was over rotation of a lateral knee?

Answer 8

• Locate smooth posterior surface of lateral condyle
• Less superimposition of tibia and fibula

Question 9

What things do erect imaging demonstrate?

Answer 9

• Progression of arthritis
• Joint space narrowing
• Varus and valgus deformities

Question 10

Describe valgus deformaties:

Answer 10

• Medial joint space of knee open
• Ankles more lateral than knees on either side

Question 11

Describe Varus deformities:

Answer 11

• Lateral aspect of knees open
• Knees more lateral than ankle on either side

Question 12

What would you see on AP standing knees?

Answer 12

• Visulization of tibial plateau
• Intercondylar fossa seen
• 1/2 of fibula superimposed with tibia

Question 13

What should you see on PA standing knees?

Answer 13

• Both knees without rotation
• Tibial plateaus in profile
• Intercondylar fossae visible