Fig. 1.

Weight bearing line (WBL), joint line convergence angle (JLCA), knee joint inclination (KI), and mechanical axis-tibial plateau (MA-TP) angle. (A) The WBL is drawn from the center of the femoral head to the center of the talus. The WBL ratio is calculated in the tibial plateau from the medial edge. (B) The JLCA is the angle formed between two tangential lines at the distal femoral and proximal tibial articular surfaces. (C) The KI is the angle between the horizontal line at the proximal tibial articular surfaces and the line parallel to the tibial plateau. (D) The MA-TP angle is the angle between the mechanical axis and the tangential line at the tibial plateau.