The diaphysis is the main or midsection (shaft) of a
long bone
The long bones are those that are longer than they are wide. They are one of five types of bones: long, short, flat, irregular and sesamoid. Long bones, especially the femur and tibia, are subjected to most of the load during daily activities ...
. It is made up of
cortical bone and usually contains
bone marrow
Bone marrow is a semi-solid biological tissue, tissue found within the Spongy bone, spongy (also known as cancellous) portions of bones. In birds and mammals, bone marrow is the primary site of new blood cell production (or haematopoiesis). It i ...
and
adipose tissue (fat).
It is a middle tubular part composed of compact bone which surrounds a central marrow cavity which contains red or yellow marrow. In diaphysis, primary
ossification
Ossification (also called osteogenesis or bone mineralization) in bone remodeling is the process of laying down new bone material by cells named osteoblasts. It is synonymous with bone tissue formation. There are two processes resulting in ...
occurs.
Ewing sarcoma tends to occur at the diaphysis.
[Physical Medicine and Rehabilitation Board Review, Cuccurullo]
Additional images
Illu long bone.jpg
File:EpiMetaDiaphyse.jpg, Long bone
See also
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Epiphysis
The epiphysis () is the rounded end of a long bone, at its joint with adjacent bone(s). Between the epiphysis and diaphysis (the long midsection of the long bone) lies the metaphysis, including the epiphyseal plate (growth plate). At the jo ...
*
Metaphysis
References
Skeletal system
Long bones
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