Leg · Long bone
Tibia (Shin Bone)
The tibia, or shin bone, is the larger of the two bones in the lower leg. It bears most of the weight below the knee and forms the front of the shin, which you can feel just under the skin.
What it is
The tibia is the main weight-bearing bone of the lower leg. It sits on the inner side, alongside the thinner fibula. Its sharp front edge lies just under the skin, which is why a knock to the shin is so painful.
Where it is
The lower leg, between the knee and the ankle, on the inner (medial) side. It runs alongside the fibula.
What it does
Carries most of the body's weight from the knee to the ankle and provides attachment for muscles that move the ankle and foot.
Connections
Joints and connections
- Knee joint (with the femur)
- Ankle joint (with the talus)
- Joints with the fibula
When things go wrong
Common injuries and conditions
- Tibial shaft fracture
- Stress fracture (from repetitive impact, e.g. running)
- Shin splints (pain along the tibia)
Education and reference only. This explains the anatomy in plain terms; it is not a diagnosis. A severe injury, a visibly deformed limb, or the inability to move or bear weight needs urgent assessment — call 999 or go to A&E for a serious injury.
Did you know?
An interesting fact
The tibia is the second-longest bone in the body after the femur.
Answers
Tibia: frequently asked questions
What is the tibia?
The tibia is the shin bone — the larger, weight-bearing bone of the lower leg, running from the knee to the ankle on the inner side.
What is the difference between the tibia and fibula?
The tibia is the larger, inner, weight-bearing bone; the fibula is the thinner outer bone that mainly stabilises the ankle. Both run between the knee and ankle.
What are shin splints?
Shin splints are pain along the tibia, usually from repetitive impact such as running. They are not a break, but persistent shin pain should be assessed to rule out a stress fracture.
Explore the leg
Related bones
Sources
Where this is drawn from
- NHS — Anatomy and body systems
- Gray's Anatomy for Students (Drake, Vogl, Mitchell)
- TeachMeAnatomy — skeletal system
Building an anatomy or patient-education resource?
We create clear, accurate, referenced medical reference content and decision aids for teams.