THE ARRANGEMENT OF HAVERSIAN SYSTEMS IN A DIAPHYSIS – 1
As seen on the previous page, the Haversian systems in the diaphysis of long bones are arranged one above the other, forming thousands of columns each measuring a few centimeters long.
The figure shows a diagram of the arrangement of lamellar bone in a diaphysis, when observed in cross-section. This diagram shows a small segment of a ring obtained by a cross-section of a diaphysis. Observe that the spaces between Haversian systems are filled with parallel bone lamellae.
Four Haversian systems, or osteons, can be observed, each highlighted in a shade of blue. The central canal of each system, called the Haversian canal, is traversed by blood vessels, lymphatics, and nerves. Observe that the spaces between Haversian systems are filled with parallel bone lamellae but they are not Haversian systems.
Blood vessels run transversely through the diaphysis within tunnels called Volkmann’s canals. Most of these blood vessels are branches of the vessels placed in the medullary canal (on the right in the figure) or, less frequently, in the periosteum.
Volkmann’s canals connect adjacent Haversian canals and build a complex system of blood circulation in the compact bone.
The vessels placed within the Haversian canal allow blood and lymphatic circulation to travel the length of each Haversian system and are responsible for nourishing the osteocytes of each osteon.
The figure shows a diagram of the arrangement of lamellar bone in a diaphysis, when observed in cross-section. This diagram shows a small segment of a ring obtained by a cross-section of a diaphysis. Observe that the spaces between Haversian systems are filled with parallel bone lamellae.
Four Haversian systems, or osteons, can be observed, each highlighted in a shade of blue. The central canal of each system, called the Haversian canal, is traversed by blood vessels, lymphatics, and nerves. Observe that the spaces between Haversian systems are filled with parallel bone lamellae but they are not Haversian systems.
Blood vessels run transversely through the diaphysis within tunnels called Volkmann’s canals. Most of these blood vessels are branches of the vessels placed in the medullary canal (on the right in the figure) or, less frequently, in the periosteum.
Volkmann’s canals connect adjacent Haversian canals and build a complex system of blood circulation in the compact bone.
The vessels placed within the Haversian canal allow blood and lymphatic circulation to travel the length of each Haversian system and are responsible for nourishing the osteocytes of each osteon.
