Coronal plane deformity around the knee in the skeletally immature population: A review of principles of evaluation and treatment

Figure 2 The malalignment test. The mechanical axis (MA) is traced from the center of the femoral head to the center of the ankle. The metaphyseal-diaphyseal angle (MAD) is calculated in millimeters (dotted lines in the image traced from center of knee and MA). If the MAD exceeds the threshold of normality, it is necessary to find the source of the deformity. The mechanical lateral distal femur angle. Medial proximal tibial angle are evaluated. A: Varus; B: Normal; C: Valgus. MAD: Metaphyseal-diaphyseal angle; MPTA: Medial proximal tibial angle; mLDFA: Mechanical lateral distal femur angle.