Crush of cord and its membranes. The result of a fracture of the spine. (Erichsen.)
The spinal column is so strongly put together and its bones so protected that fracture of any one of its component parts is inconceivable except as a result of violence. This may occur by objects falling upon it or by the body falling a distance, or from violent twisting or wrenching. These injuries constitute but a small percentage—about 3 per cent.—of all fractures. They occur more easily and commonly in the upper portion than in the lower, where the vertebræ are larger. As a result of their occupations adult males suffer much more frequently than women or children.
Diagnosis.
—The diagnosis of fracture of the vertebral column is rarely difficult. The disability produced is instantaneous if the cord itself be compressed. If the cord escape pressure there may be serious symptoms, but without paralysis. The most serious feature, then, of any fracture of the vertebræ is the amount of damage done to the cord proper. The so-called gunshot fractures of the spine have already been partially treated of above and in the chapter on Gunshot Wounds. They constitute a somewhat different class of lesions, but have, in common with those above alluded to, the actual fracturing of the bone and the question of damage to the cord. In most respects they may be considered with the non-penetrating injuries. Fractures of the spine, therefore, may be divided into (a) fractures with injury of the cord, and (b) fractures without such injury. In many cases it is difficult to state whether the cord is crushed or simply more or less compressed by bone, fluid, or exudate, until the spinal canal has been opened and explored.
When the cord is totally destroyed there will be total loss of reflexes, with motor and sensory paralysis complete. (See [Fig. 413].)
In some instances there is visible or palpable deformity. This is by no means necessarily the case. It is more likely to be noted in the upper portion of the column, where the vertebral spines are more easily palpated. If sufficient time have elapsed there will often be ecchymosis. The principal feature, however, of spinal fractures is the paralysis, which results in most instances as above. Its careful study is requisite both for minute diagnosis and localization of the injury. Paralysis, then, whether of motion or of sensation, along with the condition of the reflexes, deserves careful consideration in each instance. It is of the greatest importance, because by it, rather than by other causes, death is brought about in the majority of cases which outlive the first twenty-four hours after injury. Even injury low down, which causes paraplegia with loss of control of the bowels and bladder, may terminate fatally in time, through an ascending infection of the urinary passages, which may finally lead to pyelonephritis and death. This has often occurred as the result of inattention to precautions in the use of the catheter, and to carelessness on the part of the patient. Death, then, may be caused by roundabout methods of infection which have only accidental connection with the original injury. Other cases die of septic infection in consequence of lack of proper attention to bed-sores. Again, with cord involvement high up in the dorsal region there is very likely to occur a rapid ascending degeneration, by which, one after another, the roots of the phrenic nerves are involved in their order from below upward, until finally the patient dies of asphyxia from paralysis of all the respiratory apparatus ([Fig. 414]).
Aside from such evidences as actual displacement of the vertebral spines may afford the localizing diagnosis is made mainly by a study of the paralysis. In regard to this paralysis it should be remembered how it is produced from the very nature of the injury itself. That occurring within from a few minutes to a few hours after the injury is due to hemorrhage; that which occurs still more slowly is due to exudate or the presence of pus; while a late paralysis may result from poliomyelitis. The first form of paralysis may be produced by hemorrhage either within the central canal (hematomyelia) or hemorrhage within the membranes or structure of the cord itself (hematorrhachis).
There is another form of paralysis due to embolism which, however, has but little to do with the ordinary injuries. The following table, inserted by the courtesy of Dr. Dennis, will assist in localizing the lesion by a study of these paralyses and reflexes due to spinal injury:
Paralyses and Reflexes due to Spinal Injury.