The ankle joint is designed to be strong and flexible. The box like ankle mortise stabilises the joint, while at the same time enabling the foot to move up and down from side to side. Ligaments stabilise the joint while tendons provide for the ankle motion.

 

Ankle mortise
The box-shaped ankle mortise is formed by the lower ends of the two leg bones and houses the talus, one of the foot bones. The mortise gives lateral stability to the ankle joint while allowing a great range of motion.

 

 

 

 

 

 

 

Ankle motion
The ankle moves up and down and side to side. Moving the foot up is calleddorsiflexation, moving it down is plantar flexion; inward is inversion, outward iseversion.

 

 

 

 

Tendons and Ligaments
The outside and inside views of the ankle anatomy show the many fibrous tendons and ligaments.

 

Tendons connect muscles in the lower leg to the bones of the ankle and foot. Depending on which muscle contracts, the foot moves up, down, or from side to side. Ligaments connect bone to bone and help stabilise the ankle joint.