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.
Limbs of the horse limb of the horse runs from the pelvis to the navicular bone. After the pelvis come the femur (thigh), patella, stifle joint, tibia, fibula, tarsal (hock) bone and joint, large metatarsal (cannon) and small metatarsal (splint) bones. Below these, the arrangement of sesamoid and phalanx bones and joints is the same as in the forelimbs. When the horse is moving, the distal interphalangeal joint (coffin joint) has the highest amount of stresses applied to it of any joint in the body, and it can be significantly affected by trimming and shoeing techniques. Although having a small range of movement, the