Fibula
What it means
The fibula is the slender bone running next to the shin bone (tibia) in your lower leg, from below the knee to the outer ankle.
Even though it carries little body weight, a weak fibula can still fracture from falls or stress, signaling broader bone health concerns worth checking.
The fibula is the thinner of the two lower leg bones, running alongside the tibia (shin bone) from just below the knee down to the outer ankle. It doesn't bear much body weight compared to the tibia, but it provides stability to the ankle joint and gives muscles a place to attach.
Like other long bones, the fibula has a dense outer shell called cortical bone and plays a role in overall skeletal strength. It can be affected by the same bone-thinning processes that weaken bones elsewhere in the body, such as low bone mineral density, though fractures here are less common than at the hip, spine, or wrist.
Fibula fractures often happen from ankle twists, falls, or direct impact, and can occur as a stress fracture with repetitive strain, especially in someone with lower bone density. If you've had a fibula fracture that seemed to happen too easily, it's worth mentioning to your doctor as part of a broader look at your bone health.
The fibula carries little body weight, but a weak one can still fracture and signal wider bone issues.
Where this leads
WordThe fibula sits next to the tibia, the bone that actually carries your weight. See why the tibia's strength matters so much.
Related words
The tibia is the shin bone — the larger, weight-bearing bone running from your knee to your ankle.
A long bone is a bone that's longer than it is wide, like the femur or humerus, with a shaft and two ends. These…
Cortical bone is the dense, hard outer layer of bone that forms a protective shell and resists bending and twisting…
A stress fracture is a small crack in a bone caused by repeated stress over time, rather than a single hard blow.
An ankle fracture is a break in one or more of the bones that make up the ankle joint — usually the tibia, fibula,…
Bone mineral density (BMD) measures how much mineral is packed into your bones, usually estimated with a DEXA scan,…
Education only, not medical advice. Decisions about tests, medications and treatment belong with your own doctor. OsteoStrong does not diagnose, treat or cure any disease.
