The knobby bones on the outside and the inside of the ankle are called malleoli. The fibula and the tibia have specific parts that compose the ankle: Lateral malleolus - end of the fibula ...

One such tendon is the posterior tibial tendon. This tendon originates in the calf and extends down to the inner part of the ankle, where it is connected to the bone in the middle of your foot.

The tendon runs behind the inner ankle bone (medial malleolus) and attaches to a bone at the arch of the foot. The muscle helps support the arch and plays a significant role in running.