What is the fibula?
What is the function of the fibula?
The tibia bears most of the weight in the lower leg. The fibula takes on only a small part of the load, but is nevertheless irreplaceable: the thin bone stabilizes the lower leg and forms the upper ankle joint at its lower end together with the tibia and the talus. In addition, the fibula supports the cushioning during jumping and serves as an attachment point for the strong fibula muscles as well as tendons and ligaments.
The fibula sits next to the tibia on the outside of the lower leg. The thin bone is connected to the tibia at a total of three points: At the upper end, there is a tibia-calf joint (articulatio tibiofibularis), which is barely movable due to taut ligaments, and which fixes the head of the fibula to the tibia.
In the shaft area, the tibia and fibula are closely connected by a strong interosseous membrane, the membrana interossea. This syndesmosis ligament, which consists of connective tissue, stabilizes the lower leg and ankle joint.
Numerous muscles, tendons and ligaments attach to the fibula or fibular head. These include the long fibula muscle (Musculus peronaeus longus) and part of the thigh muscle (Musculus biceps femoris).
Complaints in the area of the fibula can have various causes. Often it is not the bone itself that is the cause, but the discomfort emanates from adjacent structures such as muscles, tendons and ligaments.
Severe pain is usually due to a fracture. Depending on the location of the fibula fracture, it is:
- fibula head fracture or a
- Fibular shaft fracture.
Occasionally, benign or malignant tumors form on the fibula. They can press on nerves and result in paralysis. These include:
- benign neoplasms: ganglion (superficial bone, spinner ganglion), enchondroma (cartilage tumor)
- Malignant bone lesions: Osteosarcoma, Ewing’s sarcoma
In rare cases, children are born with a malformation of the fibula. Examples are:
- Fibula aplasia: the fibula is missing.
- Fibula hypoplasia: The fibula is not fully developed.
