Tibia shaft fracture is a fracture of the proximal (upper) third of the tibia (lower leg bone). Due to the location of the tibia on the shin, it is the most commonly fractured long bone in the body.

Patients with tibial shaft fractures present with pain and localized swelling. Due to the pain they are unable to bear weight. There may be deformity, angulation, or malrotation of the leg. Fractures that are open (bone exposed or breaking the skin) are common.^{[citation needed]}

Since approximately one third of the tibia lies directly beneath the skin, open fractures are common compared to other long bones. These open fractures are most commonly caused by high velocity trauma (e.g. motor vehicle collisions), while closed fractures most commonly occur from sports injuries or falls. Osteoporosis can be a contributing factor. Skiing and football (soccer) injuries are also common culprits.

Prior to realignment and splinting an assessment is performed to ensure there are no open wounds, soft-tissue contusions, or neurovascular injuries.

Anteroposterior (AP) and lateral radiographs the include the entire length of the lower leg (knee to ankle) are highly sensitive and specific for tibial shaft fractures.

Two systems of fracture classification are commonly used to aid diagnosis and management of tibia shaft fractures:^{[citation needed]}

Management is dependent on the determination of whether the fracture is open or closed.^{[citation needed]}

Nonsurgical treatment of tibia shaft fractures is now limited to closed, stable, isolated, minimally displaced fractures caused by a low-energy mechanism of injury. This treatment consists of application of a long-leg cast.