Method of Aglietti et al for Measuring the Size of an Area of Osteonecrosis Involving a Femoral Condyle at the Knee

 

Radiographs taken:

(1) anteroposterior

(2) lateral

 

Measurements taken:

(1) horizontal width of the zone of osteonecrosis in cm in the anteroposterior view of the knee

(2) horizontal width of the zone of osteonecrosis in cm in the lateral view of the knee

(3) horizontal width of the affected femoral condyle in cm from peak of the intercondylar fossa to a vertical line running along the lateral border

 

surface area along the articular surface affected by osteonecrosis in square centimeters =

= (horizontal width in anteroposterior view) * (horizontal width in the lateral view)

 

ratio of the width of osteonecrosis to width of the affected condyle in the anteroposterior radiograph in percent =

= (horizontal width of area of osteonecrosis) / (horizontal width of the femoral condyle) * 100%