Functions of the tibia, also called the shinbone, include connecting the knee to the ankle in the bodies of humans and other vertebrates. The tibia bone also functions to form part of the skeleton in the lower leg, where it supports movement of the leg, creates a point where muscles are inserted, stores minerals and produces blood cells in bone marrow. Vertebrate bodies contain one tibia bone in each leg.
The tibia bears the most weight of any bone in the body, although it is the smallest of the two bones in the lower leg. The bone bears a force up to 4.7 times body weight during walking. The larger fibula bone sits behind the tibia.
Medical conditions that can negatively impact the tibia include bone cancer, osteoporosis, dislocations, infections and fractures. Fractures include those that involve only the tibia and those that involve the tibia and the fibula. Fractures involving only the tibia are the Segond fracture, Gosselin fracture and Bumper fracture.
The tibia is classified as a long bone. It contains a diaphysis and two epiphyses. The diaphysis constitutes the middle of the tibia, while the epiphyses are rounded sections on the ends of the bone. Four joints include the tibia bone: the ankle, knee and interior and superior tibiofibular joints.