Your fibula.
calcaneus
There are several bones in the Ankle. However, the one most commonly referred to as the "Ankle Bone" (the knob-like bone that protrudes out from where the ankle rotates) is called the Medial Malleolus.
The lateral malleolus is the bone marking that can be palpated at the distal end of the fibula. This structure is the bump at the outside of your ankle.
The structure of the ankle is comprised of many bones, ligaments, and muscles ranging from above the calcaneous(Heel bone) and the top of the footdown to the toes. The "Ankle bone" (bone that protrudes out) is called the malleolus. Most people commonly confuse this for the ankle bone. when it is really one of many.
The tibia is the larger bone in the lower leg, connecting the knee to the ankle. The protrusion that can be felt just below the knee cap is known as the tuberosity.
The leg bone
The talus is the largest bone of the ankle.
what can be done if you have a osseous fragment in ankle bone
The talus bone.
When the fractured bone protrudes from the skin, this is known as a compound fracture.
A broken bone heals alot faster than a ankle sprain.
Depending on the size of the ankle, it will slide down to below the ankle bone.
Ankle bone