Generality
The malleolus is the bony prominence seen on the inside and outside of each ankle.
The malleolus located on the inner side of the ankle is called the tibial malleolus, as it belongs to the tibia, one of the two bones of the leg skeleton.
The tibial malleolus and the fibular malleolus present some characteristic anatomical elements. For example, on the inner surface they have a smooth area that allows them to articulate with the talus, the tarsal bone constituting the ankle joint.
Both malleoli are the site of insertion of important ligaments: the medial (or deltoid) ligaments of the ankle and the lateral ligaments of the ankle.
The function of the tibial malleolus and the fibular malleolus is to guarantee stability to the ankle joint.
What is the malleolus?
The malleolus is the bony prominence visible on the inside and outside of each ankle.
Thus, the human skeleton has four malleoli in all, two for each lower limb.
In the language of human anatomists, the malleolus located on the inner side of the ankle is the so-called tibial malleolus or medial malleolus, while the malleolus located on the outer side of the ankle is the so-called peroneal malleolus or lateral malleolus.
Some anatomy books define the malleolus as a bony process. This is not contrary to what has been stated above "on the contrary, since the terms" bony process "and" bony prominence "have the same meaning.
CONCEPT OF MEDIAL AND LATERAL
Medial and lateral are words with the opposite meaning.
To understand its meaning, one must take a step back and imagine the human body divided into two equal and symmetrical halves: the right half and the left half. From this subdivision results, for each half, an eye, an ear, a nasal nostril, an arm, a hand, a leg, a foot, etc.
The axis that divides the human body into two equal and symmetrical halves is called the sagittal plane or median plane of symmetry.
- The word medial indicates a relationship of proximity to the sagittal plane.
The medial malleolus is the malleolus closest to the sagittal plane. - The word lateral indicates a relationship of distance from the sagittal plane.
The lateral malleolus is the malleolus furthest from the sagittal plane.
