diaphysis

anatomy

Also known as: diaphyses, shaft

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Last updated

June 25, 2026

Quick Summary

The diaphysis is the central shaft of a long bone. It is a hollow, tubular structure that contains bone marrow and is surrounded by a compact outer layer called the cortex. This region is primarily responsible for supporting weight and acting as a lever.12

In long bones, the diaphysis flares outward at its ends, transitioning into the metaphysis, which transfers loads from the joint surfaces to the diaphysis. Blood supply to the diaphysis and metaphysis is mainly provided by a nutrient artery that enters the bone and branches out. The diaphysis is formed through endochondral ossification, where a cartilage model is progressively replaced by bone.234

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bone disease
Deficient blood supply to bone
…may involve the shaft (diaphysis) or the ends (epiphyses) of the long bones. Sometimes the bone marrow of the diaphysis is primarily involved, and in osteomyelitis it is usually the compact (cortical) bone of the shaft that undergoes necrosis. For mechanical reasons, and because there is a poorer blood…
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…may involve the shaft (diaphysis) or the ends (epiphyses) of the long bones. Sometimes the bone marrow of the diaphysis is primarily involved, and in osteomyelitis it is usually the compact (cortical) bone of the shaft that undergoes necrosis. For mechanical reasons, and because there is a poorer blood…
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bone
Bone morphology
…region of the bone (diaphysis) is the most clearly tubular. At one or commonly both ends, the diaphysis flares outward and assumes a predominantly cancellous internal structure. This region (metaphysis) functions to transfer loads from weight-bearing joint surfaces to the diaphysis. Finally, at the end of a long bone…
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…region of the bone (diaphysis) is the most clearly tubular. At one or commonly both ends, the diaphysis flares outward and assumes a predominantly cancellous internal structure. This region (metaphysis) functions to transfer loads from weight-bearing joint surfaces to the diaphysis. Finally, at the end of a long bone…
Read More