CLINICAL ANATOMY
A player was kicked hard on the lateral surface of
right knee during a hockey game
• How do you feel the head of fibula?
• What important structure lies in relation to the
neck of fibula?
• What are the effects of injury to the neck of
fibula?
Answers
Answer:
The fibula is a long bone in the lower extremity that is positioned on the lateral side of the tibia. The fibula is much smaller and thinner than the tibia. It is located just behind the tibial head at the knee joint and then runs down the lateral aspect of the leg until it reaches the ankle joint. A ridge on the medial surface of the fibula forms the interosseous border where the fibula is connected to the tibia via the interosseous membrane. This connection forms a syndesmotic joint, meaning it has very little mobility.[1][2][3]
The structure of the fibula can be broken down into the head, neck, shaft, and distal end of the fibula. As the head becomes narrow distally, the fibular neck is formed. The fibular shaft lies distal to the neck and has three surfaces, lateral, medial, and posterior. The shape of the fibular shaft is determined by the muscle attachments. Initially, it is a triangular shape and distally becomes more irregularly shaped. The distal end of the fibula forms the lateral malleolus which articulates with the lateral talus, creating part of the lateral ankle. The posterior and lateral tibia form the posterior and medial malleolus, respectively.
Like the tibia, the fibula is ossified in three areas, in the middle and at either end of the epiphysis. Ossification of the fibula begins in the shaft at around the eighth week of gestation and then extends to either end. The process of ossification is complete by the second decade of life. Both ends of the fibula remain cartilaginous.
Structure and Function
Unlike the tibia, the fibula is not a weight-bearing bone. Its main function is to combine with the tibia and provide stability to the ankle joint. The distal end of the fibula has several grooves for ligament attachments which then stabilize and provide leverage during the ankle movements. The lateral (fibular) collateral ligament attaches to the lateral side of the fibular head. This ligament provides knee stability. However, the fibula itself has a little role in providing knee stability.
Blood Supply and Lymphatics
The blood supply to the fibula is from the fibular artery (also known as the peroneal artery) which has many small branches which supply the diaphysis. The epiphysis and the proximal fibular head are supplied by branches of the anterior tibial artery. The periosteum also receives numerous small branches from the fibular artery and supplies the rest of the bone. It is important to know the blood supply of the fibula because this bone is often used as a graft for reconstruction of the mandible.