Long bone

As long bone, long bone or long bone (os longum, plural Ossa longa ) is defined as bone marrow cavity with a uniform, in the bone marrow is located. Bones are found exclusively in the extremities. This can be the " long bones ", humerus (humerus ), Elle ( ulna ) and radius ( radius), thigh bone ( femur) and shinbone (tibia) and fibula ( fibula ) of the " short tubular bones ", metacarpal and metatarsal bones ( metacarpals and metatarsals ), as well as finger and toe bones (ossa digitorum manus and pedis, or simply phalanges ) are different.

Construction

The bones consist of two bone ends ( epiphyses ) and a bone shaft ( diaphysis ). The short section in the transition from the epi- metaphysis to diaphysis is called.

The two epiphyses are composed of a fine network of trabeculae that (trajectories ) are aligned with the principal directions of the applied forces. These trabeculae form a cancellous bone ( cancellous bone ) in its entirety. Between the trabeculae cavities ( Cellulae medullares ), in which red bone marrow is located. Outside the cancellous bone by a thin layer of compact bone ( substantia compacta ) coated. Still sitting in the area of the joint surfaces on a layer of hyaline cartilage.

In addition, there are often more exuberant bone; resulting from the epiphyses, as the greater trochanter to the femur or the greater tuberosity of the humerus, which are called apophysis and have its own growth plate, the Apophysenfuge.

In the diaphysis the trabecular meshwork, however, is almost completely formed and inside there is a uniform marrow cavity ( glenoid medullaris ) with yellow bone marrow ( fatty marrow ). The mechanical strength of the diaphysis is therefore of the compact bone substance ( substantia compacta Substantia or cortical ) requires that surrounds like a sleeve the medullary cavity.

Between the respective epiphysis and the diaphysis at growing individuals the epiphyseal plate ( growth plate ). It is composed of hyaline cartilage and serves the growth in length of a long bone. After completion of growth ossified epiphyseal plate and this remains as the epiphyseal line ( Linea epiphysealis ) often visible through to old age.

The entire bone is covered except at the articular cartilage surfaces of the periosteum ( periosteal ).

Through the diaphysis occurs an artery for blood supply to the bone. The opening at which the blood vessel passes through the bone shell is referred to as patent foramen nutricium, as the arteria Nutricia artery. The epiphyses have mostly own blutversorgende arteries ( arteries epiphyseales ), which are independent of the artery nutricia the diaphysis.