Distal humeral joint orientation line

The distal humeral joint orientation line is a landmark used to assess angular deformities of the humerus and provide indications for their correction.

• In the frontal plane, it is determined from a cranio-caudal radiograph or multiplanar reconstruction of the humerus: it corresponds to the line extending from the most distomedial to the most distolateral portion of the condyle of humerus.

• In the sagittal plane, it is determined from a mediolateral radiograph or multiplanar reconstruction of the humerus (the circles that best highlight the medial and lateral parts of the condyle of humerus must be concentric and not intersect): it corresponds to the line that joins the caudodistal part of the medial epicondyle of the humerus to the center of the condyle of humerus (i.e. the center of the circle that best delineates this condyle).