LAMINECTOMY (Latin lamina a plate + grech, ektome excision, removal) — removal of handles (arches) of vertebrae for the purpose of opening of the vertebral channel.
Indications and Contraindications
Produce L. at the prelum of a spinal cord of N of roots caused by the tumor, arachnoidal unions, abscess, hems formed after wounds and the closed injuries of a spinal cord, bone fragments at injuries of vertebras and metal foreign bodys, hernial protrusion of intervertebral cartilages, etc. L. can be decompressive or be made in cases of need of audit of contents of the vertebral channel (trial L.). Gemilaminektomiya — removal of a half of handles of vertebrae — is sometimes applied at the prelums of a spinal cord caused by hernial protrusion of intervertebral disks, a tubercular spondylitis. Interlaminarny L. — partial removal of adjacent handles of vertebrae — is more often applied at hernial losses of intervertebral disks.
Contraindications: acute pyoinflammatory processes (except the area leading to a prelum of a spinal cord), a decompensation of cardiovascular activity, breath, function of a liver and kidneys.
Technology of operation
In most cases L. make under a multicomponent endotracheal anesthesia nitrous oxide using muscular relaxants of N of artificial ventilation of the lungs. The general anesthesia is supplemented local infiltration and juxtaspinal with novocainic anesthesia.
Apply 0,25% to a local infiltration anesthesia solution of novocaine, juxtaspinal anesthesia of roots is carried out by 2% by solution of novocaine. The needle is entered sideways from an acantha, on 1,5 — 2 cm otstupya from it to feeling of a handle of a vertebra (fig. 1) aside. Patients with diseases and a spine injury and a spinal cord are especially sensitive to intoxications therefore it is necessary to show care during the use of solutions of novocaine.
For performance of L. the patient is stacked on the right side or on a stomach. The section of skin is carried out on 1 — 2 vertebra above and below subjects L. Dlina of a skin section depends also on depth of a wound — it more at L., made lower than XII chest vertebras. The section of skin, as a rule, linear, it is made according to the line of acanthas. If on the line of a section there are hems, they should be excised; skin away from a section in such cases otpreparovyvatsya in order that during the mending of a wound it was easier to reduce edges of a section and to reduce a tension seams. After deepening of a linear section consistently, in the beginning with one, then on the other side of acanthas, cut the ligaments and deep muscles of a back lying in paravertebral trenches, carrying out a knife directly up to a bone (fig. 2). Finish skeletonization of acanthas and handles of vertebrae with the wide raspatory. At suspicion on a change of handles it is necessary to separate muscles from a bone scissors in order to avoid wound mobile fragments of elements of a spinal cord. After allocation from muscles of acanthas for the purpose of a stop of bleeding the educated interval between bones and muscles is hardly tamponed gauze tampons (fig. 3) moistened with hot isotonic solution of sodium chloride. Skeletirovanny acanthas have a bite at the basis bone nippers to handles of vertebrae (fig. 4) and delete together with interspinal sheaves. Then the raspatory handles of vertebrae skeletirut (important in previously acute way to separate them at the edges from sheaves). Skusyvany handles of a vertebra make Egorov or Borkhardt's curved nippers to joint shoots, without pressing cheeks of nippers on a firm meninx and a spinal cord, avoiding possible damage them. It is not necessary to apply a chisel to removal of handles and acanthas at all. Skusyvaniye of handles is more convenient to begin them with median departments, and then to continue in the parties to joint shoots. The Lateralny skusyvaniye of handles of the last should not be made since wound of veins is possible; in cervical vertebras it threatens with wound of a vertebral artery. Skusyvaniye of handles of upper chest vertebrae it has to be limited to medial border of joints between joint shoots in view of a possibility of damage at this level of not falling down, deprived valves of the intervertebral veins giving at the same time long persistent bleeding; the air embolism is possible.
Usually skusyvat sites of handles within 2 — 3 cm. At L., as a rule, delete from 3 to 5 handles (fig. 5) though the number of the deleted handles can be more that is defined by character patol, process.
After removal of handles in a wound Epidural cellulose with the passing veins (an internal vertebral veniplex) which are fixed to cellulose predlezhit, are badly fallen down and have no valves. At disturbance of venous outflow at patients with a prelum of a spinal cord and its covers epidural veins can be sharply expanded, their damage during L. can cause considerable venous bleeding, also air embolism is possible (on system at. hemiazygos — v. cava sup. — the right heart — a pulmonary trunk). Therefore at the begun venous bleeding the immediate tamponade the wadded strips entered epiduralno is obligatory. Because of danger of an air embolism during L. use for the purpose of a hemostasis of hydrogen peroxide is not shown.
After a section of epidural cellulose on the centerline and moving away it in the parties finds a firm cover. Not changed firm cover of grayish color with slightly bluish shade, insignificant gloss or opaque. At absence patol, changes the pulsation of a dural bag synchronously with pulse and its more rare fluctuations matching breath is noted. At a prelum of a spinal cord the pulsation is imperceptible. After approach to a firm meninx make necessary actions for elimination patol, the center.
On the course of an operative measure make a careful hemostasis, and then layer-by-layer mending of a wound to three floors tightly. The firm cover is sewn up with the continuous silk suture imposed whenever possible hermetically (fig. 6). In cases when there is a doubt in care of a hemostasis, in a bottom corner of a wound for one days the rubber drainage can be left. On the site where the drainage is left, impose the provisional (not tied) seam. In a day the drainage is deleted, empty a hematoma and knot a provisional seam.
At wide L. disturbance of stability of a backbone is observed. The prevention of such complication is the economical resection of handles of vertebrae with preservation of intervertebral joint shoots. At extensive L. according to indications the stabilizing operations can be performed (see. Spondylodesis ).
Bibliography: The multivolume guide to surgery, under the editorship of B. V. Petrovsky, t. 4, page 307, M., 1963; Experience of the Soviet medicine in the Great Patriotic War of 1941 — 1945, t. 11, page 247, M., 1952; Romodanov A. P., Dunayevsky A. E. and Orlov Yu. A. Tumors of a spinal cord, M., 1976, bibliogr.; Ugrgomov V. M. and Babichenko E. I. The closed injuries of a backbone and a spinal cord, page 142, L., 1973.
V. M. Ugryumov.