Anatomy Guide › Lower limb
Tibia
The tibia, or shinbone, is the second largest bone in the body and the true weight-bearer of the lower leg: nearly all the load from the femur passes through it to the ankle, while its slender neighbor the fibula carries only a small share. Its broad top surface forms the floor of the knee joint, receiving the femur's rounded condyles on two shallow plateaus cushioned by the menisci.
What makes the tibia unforgettable in daily life is its front border. The bone's sharp anterior crest lies directly under the skin with no muscle padding for most of its length — the 'shin' — which is why a knock against a coffee table hurts so distinctively and why soccer players wear guards over this one bone. That bare surface is also why open fractures of the tibia are more common than of any other long bone: there is little soft tissue to keep broken ends from breaching the skin, a fact that shapes how these injuries are treated.
At its lower end the tibia broadens into the ankle's ceiling and its inner wall — the medial malleolus, the hard knob on the inside of your ankle. Runners know the tibia through 'shin splints,' an overuse irritation of the bone's surface layer and muscle attachments, and through tibial stress fractures, the classic too-much-too-soon running injury.
In Anamo, the tibia runs the inner lane of the lower leg from knee to ankle. It pairs with the fibula laterally, and its neighbors — patella above, talus below, the long toe extensors crossing in front — turn a hot tibia reading into a quick regional solve.
- Carries nearly all body weight passing through the lower leg
- Its bare front crest is the 'shin' everyone has bruised
- The inner ankle knob (medial malleolus) is its lower end
- The most common long bone to suffer open fracture
Think you could find the tibia on a 3D model? Play Anamo and test yourself — every guess is color-coded by how close it lands to the mystery structure.