Synonyms
Head of fibula, head of fibula, external ankle, lateral malleolus, caput fibulae Medical: Fibula
Anatomy
The fibula of the fibula forms the two bones of the lower leg with the tibia. Both bones are connected by fibers (Membrana interossea cruris). The fibula of the fibula lies on the outside of the lower leg.
The head of the fibula is palpable on the outside directly below the knee joint. However, it is not involved in the formation of the knee joint. Anatomically, the fibula can be divided into three sections.
The head forms the upper end and lies with its joint surface against the adjacent tibia. The fibula has three sharp edges which serve as muscle origins and limit the three sides of the bone. At the lower end, the fibula runs out into the so-called lateral malleolus, which forms the outer ankle.
It is visible from the outside and forms part of the upper ankle joint with the medial malleolus of the tibia. Together with the tibia, the head of the fibula forms the tibial fibula joint (fibulo-tibial joint). The bone tapers towards the shaft and widens again towards the outer ankle (malleolus lateralis). The outer malleolus of the fibula forms the upper ankle joint with the inner malleolus of the tibia. In the ankle joint area, the fibula and tibia are strongly connected by a special fiber connection (syndesmosis).
Function
Almost the entire force transmission from the thigh to the foot takes place via the shin bone (tibia). The fibula is only indirectly involved with the head of the fibula (fibula head) at the knee joint with the tibia fibula joint. The fibula at the upper ankle joint has a more important function. The outer ankle of the fibula forms the outer part of the upper ankle joint.
Function of the fibula head
The fibula head has two main functions. Firstly, it has articular cartilage on part of its surface, through which it is connected to the adjacent tibia. This connection serves to distribute the force during the occurrence, from the upper ankle joint, in which the fibula is involved, over the tibia, up to the strong femur. On the other hand, the head of the fibula serves as a point of attachment for various ligaments of the knee joint and thus contributes to its lateral stabilization.
