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

License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited. Purpose. To describe a reliable method of predicting native joint line and posterior condylar offset (PCO) using true lateral digital radiographs of the distal femur. Methods. PCO was measured relative to a line drawn parallel to the posterior cortex of the distal femur and the joint line wasmeasured from the posterior condylar flare to the articular surface. A ratio was then calculated for these measurements relative to the width of the femur at the level of the flare. Two independent observers measured PCO and joint line ratio for 105 radiographs of the different knees and one repeated thesemeasurements after one week. Results.There was a significant correlation between the width of the femoral diaphysis at the level of the posterior condylar flare with joint line