key term - Fibula

Definition

The fibula is a long, thin bone located on the lateral side of the tibia in the lower leg. While it is not weight-bearing, it serves as an important support structure for muscles and ligaments, contributing to the stability of the ankle and providing attachment points for various tendons.

5 Must Know Facts For Your Next Test

1. The fibula is often referred to as the 'calf bone' and runs parallel to the tibia on the outer side of the lower leg.
2. Despite its slender structure, the fibula plays a crucial role in stabilizing the ankle joint and providing support for muscles that control foot movement.
3. Fractures of the fibula can occur without damage to the tibia due to its non-weight-bearing nature, although they can still impact overall leg function.
4. The fibula has two ends: the proximal head, which articulates with the tibia near the knee, and the distal end, which forms part of the lateral malleolus at the ankle.
5. In some species, such as certain birds, the fibula is reduced or absent entirely, reflecting adaptations to their specific locomotor needs.

Review Questions

• How does the fibula contribute to the overall function of the lower leg?
  • The fibula contributes to lower leg function primarily by providing structural support and stability for both muscles and ligaments. Even though it is not a weight-bearing bone like the tibia, it plays a key role in stabilizing the ankle joint, allowing for proper movement during activities such as walking or running. Additionally, it serves as an attachment point for various muscles that facilitate foot motion.
• Discuss the clinical significance of fibula fractures and their impact on mobility.
  • Fibula fractures can be clinically significant despite the bone's non-weight-bearing status. These fractures may disrupt muscle attachment points or affect ligament stability around the ankle joint. Consequently, patients may experience issues with balance and mobility even after healing. Rehabilitation may be necessary to restore full function and strength to surrounding muscles.
• Evaluate how variations in fibula morphology among different species influence their locomotion patterns.
  • Variations in fibula morphology can significantly influence locomotion patterns across species. For example, in certain birds, a reduced or absent fibula allows for a lighter skeletal structure that enhances flight efficiency. In contrast, mammals with a more robust fibula generally exhibit adaptations suited for running or climbing. This morphological diversity reflects evolutionary pressures related to habitat and movement style, showcasing how form directly relates to function in vertebrate anatomy.

Related terms

tibia:

The tibia, or shinbone, is the larger and stronger of the two bones in the lower leg, which bears most of the body’s weight and connects the knee to the ankle.

ankle joint: The ankle joint is a complex structure formed by the meeting of the tibia, fibula, and talus bones, allowing for movement and flexibility in the foot.

ligaments: Ligaments are tough, elastic bands of connective tissue that connect bones to other bones at joints, providing stability and support to the skeletal system.