The injuries to which a bone is liable are Contusions, Open Wounds, and Fractures.
Contusions of Bone are almost of necessity associated with a similar injury of the overlying soft parts. The mildest degree consists in a bruising of the periosteum, which is raised from the bone by an effusion of blood, constituting a hæmatoma of the periosteum . This may be absorbed, or it may give place to a persistent thickening of the bone— traumatic node .
Open Wounds of Bone of the incised and contused varieties are usually produced by sabres, axes, butcher's knives, scythes, or circular saws. Punctured wounds are caused by bayonets, arrows, or other pointed instruments. They are all equivalent to compound, incomplete fractures.