Functional Anatomy

The ankle is the most frequently injured joint. Decisions on management are based on clinical examination and x-rays. Classification of ankle fractures is important for estimation of the stability of the joint and the severity of the ligamentous injury. The Weber and the Lauge Hansen classification both focus on the appearance of the fibular fracture and stress the role of the lateral complex in stabilizing the ankle joint.
Stability of the ankle mortise relies on the configuration of the osseus structures and the ligaments.

Question:What is the main articulation in the ankle joint and explain why.