Architecture of the lower end of the human tibia.

The cancellous bone in the lower end of the human tibia is divisible into 3 broad categories, according to the density and disposition of its lamellae. Parallel fenestrated tubes of cancellous bone arise perpendicular to the inferior articular facet of the tibia and meet the shaft obliquely. They diverge from the neutral axis which inclines posterolaterally from the centre of the inferior articular facet. Horizontal lamellae course the medial malleolus, at right angle to its articular facet. The density of the cancellous bone decreases from the periphery to the neutral axis. Spicules of thin bone can be traced from the attachment of ligaments into cancellous bone lying perpendicular to the articular facets.