Femur the medial, gives attachment to the fibular collateral ligament of the knee-joint. The femur develops from the limb buds as a result of interactions between the ectoderm and the underlying mesoderm, formation occurs roughly around the fourth week of development. By the sixth week of development, the first hyaline cartilage model of the femur is formed by chondrocytes. Endochondral ossification begins by the end of the embryonic period and primary ossification centers are present in all long bones of the limbs, including the femur, by the 12th week of development. The hindlimb development lags behind forelimb development by 1–2 days.
Tibia shaft fracture Tibia shaft fracture Tibia shaft fracture is a fracture of the proximal (upper) third of the tibia (lower leg bone). Due to the location of the tibia, it is frequently injured. Thus 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 malroation of the leg. Fractures that are open (bone exposed or breaking the skin) are common. Since approximately one third of the tibia lies directly beneath the skin, open fractures