SPINAL COLUMN, SURGERY OF. Most operations on the vertebral column are designed to relieve some condition of the enclosed spinal cord. The essentially degenerative diseases (tabes dorsalis, disseminated sclerosis, etc.) offer little scope for surgery, which finds its richest field in cases of cord compres sion. Spina bifida, a congenital defect in development, calls for operation in selected cases only, for most sufferers from this condition die during the first weeks or months of life.
There is one fundamental fact which we must grasp if we wish to understand the possibilities of spinal surgery : that regeneration is impossible, so that once the cord, and the long conduction tracts of which it is composed, suffers actual anatomical damage, that damage is permanent and cannot be undone. It is, therefore, useless to operate if it is certain that the cord has actually been lacerated, or has been so long and so severely compressed that return of function is unlikely or impossible.
are generally due to indirect violence,
the fracture occurring at a point distant from that at which the force was applied. Thus most injuries of the cervical spine (neck) are due to injuries applied to the head, whilst forcible flexion of the trunk by a weight falling on the shoulders (the common mechanism in pit accidents from a fall of "roof" or "dirt") causes a fracture at the first lumbar vertebra. The 24 bones which make up the cervical, thoracic and lumbar spine are not equally prone to injury; the three predominant sites where fractures or disloca tions occur are at the points where the qualities and range of movement change—at the second cervical, where the compound movements of the head change over into the ordinary movements of the neck, at the disc between the fifth and sixth cervical where the cervical mobility changes into the relative fixity of the chest, and at the first lumbar where the latter joins the rod-like lumbar portion. The bodies of the vertebrae can be compressed or broken without injury to the spinal cord (so-called "Kiimmells' disease") provided there is no sliding of the broken parts on one another. A fact which colours our whole attitude towards spinal injury to-day is that when the cord is damaged the lesion is inflicted at the moment of injury. The old teaching was that the cord was being compressed by bone fragments and hence early operation was advised. To-day we treat these cases with conservatism, re
duce fractures by manipulation, and operate only when deteriora tion is setting in or pain is severe. But operation is never done as an immediate urgency. X-Rays are of the greatest help. In sum mary, the cord lesion associated with most injuries is central haemorrhage or actual laceration, and operation will not often be of service in the worst cases.
Once the diagnosis is reasonably certain it is best to operate early, for these growths are commonly (Els berg gives 82%) outside the cord and can be dislodged by lami nectomy. An incision is made over the spinous processes, the laminae are exposed by clearing the muscles with a rongeur and some three of them are removed. The dura mater is incised, if the tumour has not already been found outside. The results in many cases are dramatic and the palsied may indeed be made to walk upright. When the tumour lies in the cord tissue, nothing of great service can be achieved. Deep X-Ray therapy is the only hope for such conditions, but only a few successes have so far been recorded. Little noticeable weakness follows a laminectomy per se.
Tuberculosis of the vertebral column is com monest in the very young, and gives good results by fixation on frames or in plaster jackets. Long periods of recumbency (1-3 years) are generally required. In order to render sufferers ambu lant at an earlier time, bone-grafting operations have been devised. Albee advised this so-called "internal splinting" and recommended that a long thick graft should be taken from the tibia and inserted into a bed prepared for it over the bared spinous processes and laminae at the region affected, including two healthy vertebrae above and below. Hibbs later introduced the operation of "spinal fusion"; in this no new bone is implanted but the spinous pro cesses and laminae are split and turned up and down to produce a mass of bone which will lock the bones together. The operations are most useful in persons of less tender years than are the ma jority of sufferers from Pott's disease. In Great Britain and Europe generally, excellent results are obtained by less drastic means, but in those who cannot afford a long convalescence these operations should be considered.