Various kinds of solution of continuity are met with in the vertebral column as results of external violence; and their characters are those of incised, punctured, or gunshot wounds, according to the instrument by which the injury was inflicted. The accidents to which the spine is most subject, however, are fracture of the bodies of the vertebrae, and laceration of the intervertebral cartilages. Though sometimes broken longitudinally, the bodies are much more liable to transverse fracture; very commonly one or several vertebrae are found comminuted, and the line of fracture runs in various directions. The injury which the spinal marrow sustains in these accidents usually renders them speedily fatal; but sometimes it may be observed, after death, that the fragments have begun to unite together by means of a scanty production of callus: it is extremely rare to meet with a specimen in which union has been completed. Fractures of the odontoid process of the axis present considerable interest; for in a few rare cases they have not only not proved fatal, but have even existed a considerable time without union of the fragments. A specimen of this kind is contained in the Vienna Museum.

The intervertebral substances are usually lacerated only when one or more vertebrae are at the same time broken or crushed.

The lateral articulations of the vertebrae are more rarely dislocated in proportion to their distance from the occiput and two upper cervical vertebrae.

Anchylosis is sometimes found in the spinal column at the time of birth, but it more frequently comes on later in life. The union takes place sometimes between the bodies of the vertebrae, the adjoining margins and surfaces of which are then connected together, and sometimes between their lateral articulations: it is also very common to find anchylosis in both situations. When the bodies are anchylosed, it may be by the union of their surfaces, which meet each other when the intervertebral substances have been removed by absorption or by inflammation and suppuration; or, it may be by a deposit of new bone at their margins, which passes, like a bridge, across the interspace between the bodies, and encloses the intervertebral substance in an osseous capsule; or, again, by a mass of bone (osteophyte), which seems as if it had been poured, when fluid, along the front of the vertebral bodies, and, then coagulating, had united them into one piece. Each kind of deposit forms transverse swellings between every two adjoining vertebrae: sometimes they grow, too, on the back of the column, and then they may prove dangerous, from their pressure on the cord (Key). Anchylosis of the lateral joints of the column may, of course, come on when the bodies are fixed in the manner just described; and it may take place between the atlas and axis, on the shortened side, in long-standing cases of wryneck. It may also result from inflammation and suppuration of the articular structures, from caries, and so forth.