COCCYGODYNIA, so called, at times de mands the removal of the coccyx, which is performed by enucleating it through a longitudinal incision, made directly over it. But the great majority of cases that suffer from pain in the coccyx do so because of some other disturbance,— either a misplaced uterus or exhausted nervous system,—and such cases must be very carefully excluded before the diagnosis of coccygodynia is made, other wise, although the bone be removed, the pain will continue.
Laminectomy. — Access to the spinal canal for the purpose of relieving press ure on the cord caused by fracture, ab scess, inflammatory exudates, or tumors or for any other purpose is almost al ways obtained by removal of the lam inee of the vertebra?. The entire back should be prepared for operation with great care. If possible, the operating table should be provided with a. hot-water plate or other means of keeping the pa tient warm to lessen the shock, which is often severe, and means should be at hand for subcutaneous injection of salt solution in addition to the ordinary stimulants. A large number of hemo static forceps will be required, as very many bleeding-points must be seized at once.
In many cases the difficulty which has given rise to the necessity for operation has interfered more or less with the func tion of respiration, and, as the patient is of necessity placed in the prone or semi prone position, the anesthetist must pay more than usual attention to the condition of the patient.
Many surgeons advise making a single straight incision in the median line, which should be long enough to include five or six vertebra. The muscles are then retracted to such an extent as to uncover the lamina on one side. A short cutting knife should be used to free the mus cles from the bone, for, if a dull instru ment is used, the tissue is apt to be so badly lacerated that necrosis follows.
Hemorrhage is apt to be very profuse at this stage of the operation, but time will be wasted if the surgeon attempts to catch vessels. He should, instead, pro ceed rapidly to complete the incision and stop the bleeding by pressure of com presses wrung out in water as hot as can be borne by the hand. The wound should be tightly packed while the lam ina on the other side of the spine are being exposed. The second wound is
then packed and the bleeding checked in the first. Peroxide of hydrogen at this stage is of use as an hemostatic. The interspinous ligament is cut through. In the dorsal region the incision must be made in a slanting direction, owing to the overlapping of the upper over the lower vertebra. With a rongeur or some of the various kinds of rib-cutters the lamina are then cut through and removed.
Instead of this plan a number of sur geons of experience prefer making an osteoplastic resection, using an II or U incision. Some of them use Hey's saw or a chisel to divide the lamina. Care must be had to make the cut through the lamina at a sharp angle, otherwise it will not enter the spinal canal. The interspinous ligament of the vertebra at the cross-cut is now divided, and the flap with the spinous processes and arches attached is now reflected upward and to one side, otherwise the spinous processes will strike each other and prevent lift ing the flap.
When the arches have been removed, a layer of adipose tissue is met with; this should be divided in the median line and pushed aside, when the dura will be brought into view. Bleeding, which oc curs during this process, can be con trolled by pressure, hot water, and per oxide of hydrogen. The cord should pul sate. If it does not, the absence of pul sation may point to adhesions, swelling of the cord, or pressure by bone or fluid. If relief from bone-pressure is being sought, it often is not enough to remove the lamina, as the pressure may be caused by encroachment on the anterior surface of the spinal canal. To reach this the spinal cord may be drawn to one side by an aneurism needle or other blunt hook, and this proceeding will be much facili tated if the two extremities of the pa tient's trunk are supported on sand-bags, making the spine concave posteriorly, so as to relax tension on the cord. Should it be necessary to divide any nerve-roots in order to move the cord far enough to one side to reach the bodies of the verte bra, these nerves should be sutured be fore the close of the operation.