Anatomy of the Ankle

The ankle is a complex articulation made up of two joints, the ankle joint, and the subtalar joint. The two bones of the shin, the tibia on the inside and the fibula on the outside, join the talus to form the ankle joint. The ankle joint allows up and down motion to take place easily, but is injured with twisting stresses. The ankle is the most frequently injured joint in sport. Tears of the ligaments are known as sprains, and need evaluation of the degree of tear for appropriate treatment plans to be formulated. The most frequently injured ligaments are the anterior fibulo-talor, and fibulo-calcaneal ligaments on the outside of the joint. The anterior inferior tibiofibular ligament can be injured with rotational stresses, and needs to be differentiated from the classic inversion sprain for adequate treatment.

The subtalar joint is composed of the talus on top and the calcaneus below. The subtalar joint allows side to side motion in the ankle. Injuries to this joint usually involve major trauma. Excessive motion in this joint is a frequent culprit in overuse injuries of the lower extremity such as shin splints, knee pain, hip and back discomfort. A biomechanical evaluation may reveal the need for orthotic control of the foot as a simple solution to these common chronic problems.