This is the central neurovascular canal of the osteon. These canals vary in size and tend to be larger nearer the medullary cavity. They have an average diameter of 50 micrometers, but range in diameter from 25 to 100 micrometers. They typically house a couple of capillaries and small nerve fibers wrapped in a loose connective tissue. They are lined by collagen fibers and numerous canaliculi perforate their walls.

Central is Latin meaning to the center. Osteon is Greek for bone. Canal is from the Latin canalis meaning a little duct, tube, or passage.