The fibula is more than just a calf bone; it is a surgical powerhouse.

Health · Published 3 October 2026 Swipe more like this →

In short: Often overshadowed by the weight-bearing tibia, the slender fibula is the third longest bone in the human body. While it does not form part of the knee joint, this versatile bone is essential for ankle stability and has become a critical resource for reconstructive surgeons repairing the human jaw.

The fibula is the outer, more slender of the two bones in the lower leg. Anatomically, it runs from just below the knee to the ankle, where it forms the lateral malleolus, the outer projection of the ankle joint. Unlike the tibia, which bears the body's weight, the fibula serves primarily as an attachment point for muscles and ligaments. Its shape is notably influenced by the strength of the muscles attached to it, and it is connected to the tibia throughout its length by an interosseous membrane.

Beyond its role in the leg, the fibula is highly valued in modern medicine for mandibular reconstruction. Surgeons often use segments of the fibula to rebuild the jawbone after trauma or disease. Because the bone is supplied by the fibular artery, it can be harvested as a free flap for tissue transfer. During these procedures, surgeons typically preserve the proximal and distal ends of the bone—roughly 4 cm and 6 cm respectively—to maintain structural integrity, while utilizing the middle third for the graft.

Clinical issues involving the fibula often center on fractures, which can occur in isolation or alongside ankle and tibial injuries. Avulsion fractures, where ligaments or muscles pull a piece of bone away, are a specific risk, as are stress fractures common in long-distance runners. Osteoporosis also poses a significant threat, as it weakens the bone and increases the risk of unexpected breaks. Because symptoms like pain or deformity may not always be obvious, bone density scans, such as DEXA, are the standard diagnostic tool for assessing fibular health.

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