A Technique of Predicting Radiographic Joint Line and Posterior Femoral Condylar Offset of the Knee

Figure 1

Measurement of joint line on the lateral radiograph to the distal femur. Joint line was measured (A) from the point at the tangent of the posterior cortex of the femur that crossed the flare of posterior condyles to the distal femur along that line. The joint line ratio was calculated by dividing the width of the femoral diaphysis at the level of the condylar flare (B) by the joint line (A/B).