The tibia (ˈtɪbɪə), shinbone, or shankbone is the larger and stronger of the two bone

Bone

Bones are rigid organs that constitute part of the endoskeleton of vertebrates. They support, and protect the various organs of the body, produce red and white blood cells and store minerals. Bone tissue is a type of dense connective tissue...

s in the leg

Leg

Łęg may refer to the following places in Poland:*A former name for the town of Ełk *Part of the Czyżyny district of Kraków*Łęg, Pleszew County in Greater Poland Voivodeship...

 below the knee

Knee

The knee joint joins the thigh with the leg and consists of two articulations: one between the fibula and tibia, and one between the femur and patella. It is the largest joint in the human body and is very complicated. The knee is a mobile trocho-ginglymus , which permits flexion and extension as...

 in vertebrates (the other being the fibula), and connects the knee with the ankle bones.
The tibia is named for the Greek aulos

Aulos

An aulos or tibia was an ancient Greek wind instrument, depicted often in art and also attested by archaeology.An aulete was the musician who performed on an aulos...

 flute, also known as a tibia.
It is commonly recognized as the strongest weight bearing bone in the body.

In humans

The tibia is found next to the fibula. It is the second largest bone in the human body, the largest being the femur

Femur

The femur , or thigh bone, is the most proximal bone of the leg in tetrapod vertebrates capable of walking or jumping, such as most land mammals, birds, many reptiles such as lizards, and amphibians such as frogs. In vertebrates with four legs such as dogs and horses, the femur is found only in...

. The tibia articulates with the femur

Femur

The femur , or thigh bone, is the most proximal bone of the leg in tetrapod vertebrates capable of walking or jumping, such as most land mammals, birds, many reptiles such as lizards, and amphibians such as frogs. In vertebrates with four legs such as dogs and horses, the femur is found only in...

 superiorly, the fibula laterally and with the talus

Talus bone

-External links:* *...

 inferiorly.

Sex differences

In the male, its direction is vertical, and parallel with the bone of the opposite side. In the female, it has a slightly oblique direction downward and laterally, to compensate for the greater obliqueness of the femur. Studies are inconclusive, however.

Structure

It is prismoid in form, expanded above, where it enters into the knee-joint, contracted in the lower third, and again enlarged but to a lesser extent towards the ankle joint.

The superior tibiofibular articulation

Superior tibiofibular articulation

The proximal tibiofibular articulation is an arthrodial joint between the lateral condyle of the tibia and the head of the fibula.The contiguous surfaces of the bones present flat, oval facets covered with cartilage and connected together by an articular capsule and by anterior and posterior...

 is an arthrodial joint

Joint

A joint is the location at which two or more bones make contact. They are constructed to allow movement and provide mechanical support, and are classified structurally and functionally.-Classification:...

 between the lateral condyle

Lateral condyle of tibia

The lateral condyle is the lateral portion of the upper extremity of tibia.It serves as the insertion for the Biceps femoris muscle....

 of the tibia and the head of the fibula. The inferior tibiofibular articulation

Inferior tibiofibular articulation

The distal tibiofibular joint is formed by the rough, convex surface of the medial side of the distal end of the fibula, and a rough concave surface on the lateral side of the tibia.Below, to the extent of about 4 mm...

 (tibiofibular syndesmosis

Inferior tibiofibular articulation

The distal tibiofibular joint is formed by the rough, convex surface of the medial side of the distal end of the fibula, and a rough concave surface on the lateral side of the tibia.Below, to the extent of about 4 mm...

) is formed by the rough, convex surface of the medial side of the lower end of the fibula, and a rough concave surface on the lateral side of the tibia. The tibia is connected to the fibula by an interosseous membrane

Interosseous membrane

An interosseous membrane is a broad and thin plane of fibrous tissue that separates many of the bones of the body. It is an important component of many joints.Interosseous membranes in the human body:* Interosseous membrane of the forearm...

, forming a type of joint called a syndesmosis

Syndesmosis

A syndesmosis is slightly movable articulation where the contiguous bony surfaces are united by an interosseous ligament, as in the inferior tibiofibular articulation...

. The forward flat part of the tibia is called the fibia, often confused with the fibula.

Blood supply

The tibia derives its arterial blood supply from two sources:

1. the nutrient artery
   Nutrient artery
   The medullary or nutrient artery, usually accompanied by one or two veins, sends branches upward and downward to the bone marrow, which ramify in the medullary membrane, and give twigs to the adjoining canals. Nutrient Arteries are the most apparent blood vessels of the bones....
   
    (main source)
2. periosteal vessels derived from the anterior tibial artery
   Anterior tibial artery
   The anterior tibial artery of the lower limb carries blood to the anterior compartment of the leg and dorsal surface of the foot, from the popliteal artery.It is accompanied by a deep vein, the anterior tibial vein, along its course....
   
   

Strength

The tibia has been modeled as taking an axial force during walking that is up to 4.7 bodyweight. Its bending moment

Bending Moment

A bending moment exists in a structural element when a moment is applied to the element so that the element bends. Moments and torques are measured as a force multiplied by a distance so they have as unit newton-metres , or pound-foot or foot-pound...

 in the sagittal plane in the late stance phase is up to 71.6 bodyweight times millimetre.

In other animals

The structure of the tibia in most other tetrapods is essentially similar to that in humans. The tuberosity of the tibia, a crest to which the patellar ligament

Patellar ligament

The patellar ligament is the central portion of the common tendon of the Quadriceps femoris, which is continued from the patella to the tuberosity of the tibia.-Anatomy:It is a strong, flat, ligament, about 10 cm...

 attaches in mammals, is instead the insertion point for the tendon of the quadriceps muscle in reptiles, birds, and amphibians, which have no patella.

See also

• Bone terminology
• Terms for anatomical location
• Ossification of tibia
  Ossification of tibia
  The tibia is ossified from three centers : one for the body and one for either extremity. Ossification begins in the center of the body, about the seventh week of fetal life, and gradually extends toward the extremities....
  
  
• Upper extremity of tibia
  Upper extremity of tibia
  The upper extremity of the tibia is large, and expanded into two eminences, the medial condyle and lateral condyle.-Facets:The superior articular surface presents two smooth articular facets....
  
  
• Body of tibia
  Body of tibia
  - Borders :The anterior crest or border, the most prominent of the three, commences above at the tuberosity, and ends below at the anterior margin of the medial malleolus...
  
  
• Lower extremity of tibia
  Lower extremity of tibia
  The lower extremity of the tibia, much smaller than the upper extremity of tibia, presents five surfaces; it is prolonged downward on its medial side as a strong process, the medial malleolus.- Surfaces :...
  
  
• Shin Splints
  Shin splints
  Shin splints or medial tibial stress syndrome refers to pain along or just behind the shins with sports that apply extreme pressure to the legs, such as gymnastics...
  
  
• Squatting facets