Haversian systems consists of closely packed osteons or haversian
systems. The osteon consists of a central canal called the osteonic (haversian)
canal, which is surrounded by concentric rings (lamellae) of matrix.
Between the rings of matrix, the bone cells (osteocytes) are located in
spaces called lacunae. Small channels (canaliculi) radiate from the
lacunae to the osteonic (haversian) canal to provide passageways through
the hard matrix. In compact bone, the haversian systems are packed
tightly together to form what appears to be a solid mass. The osteonic
canals contain blood vessels that are parallel to the long axis of the
bone. These blood vessels interconnect, by way of perforating canals,
with vessels on the surface of the bone.
Haversian Systems Picture
Haversian systems is the basic unit of structure in compact bone,
consisting of a haversian canal and the concentrically arranged lamellae of
bone surrounding the canal. These units are secondary osteons with
Notice the Haversian cannel in the picture. You cans see the structure
from the inside and the compact bone surrounding it.