Knee series film check

The AP

On a good AP knee, the femorotibial joint space is open, the femoral condyles look symmetric, and about half of the fibular head is hidden behind the tibia. The leg is turned in about 3 to 5 degrees so the epicondyles are parallel to the IR. If the fibular head is completely hidden or completely free, or the condyles look lopsided, the leg was rotated. A narrowed joint space usually means the CR angle did not match the patient. Measure from the ASIS to the tabletop: under 19 cm angle 3 to 5 degrees caudad, 19 to 24 cm keep it perpendicular, over 24 cm angle 3 to 5 degrees cephalad.