knochenschaft
Knochenschaft refers to the shaft of a long bone. Long bones, such as the femur (thigh bone) and humerus (upper arm bone), are characterized by their elongated cylindrical shape. The shaft, also known as the diaphysis, constitutes the main body of the bone. It is composed primarily of compact bone, which provides strength and rigidity. The outer surface of the diaphysis is covered by a membrane called the periosteum, a vital layer for bone growth, repair, and nourishment. Inside the compact bone, there is a hollow cavity called the medullary cavity, which in adults contains yellow bone marrow. This marrow is primarily fat tissue, though it can convert to red bone marrow for blood cell production under certain conditions. The diaphysis serves as the primary site for bone lengthening during growth and provides the structural framework for the limb. It is a critical component in transmitting forces and allowing for movement. Fractures occurring in the knochenschaft are common and can have significant implications for mobility. The structural integrity and composition of the knochenschaft are essential for overall skeletal function.