lumbar spondylolisthesis reduction and internal fixation surgery

With the advancement of spinal surgery and the creation and increase of new instruments and internal fixation, the reduction of the vertebral body has become a reality. The use of the harrington device, the roy-camille plate, the steveffe plate, etc., has been successfully reported for the reduction of the vertebral body, but there is a disadvantage that the internal fixation is not reliable or the restoring force is insufficient. The authors used pupillary slip plate (schnollner1973) and modified plate to treat l5 and l4 slip, and performed posterior interbody fusion, and achieved satisfactory results. The ideal degree of reduction can also be achieved by slipping off the vertebral body without ventral approach and then fixing it by posterior reduction. The main advantages of sacral slip plate in the treatment of lumbar spondylolisthesis are: 1 large reduction force, good effect, 2 decompression completely, 3 high bone graft healing rate, 4 no false joints, can achieve the modern basic principle of treating lumbar spondylolisthesis - reduction Pressure, reset, and stability requirements. This article focuses on the reduction and internal fixation of the pupillary slip plate. Treatment of diseases: lumbar disc herniation, thoracic disc herniation Indication 1. Different causes, different degrees of l4 and l5 slippage are surgical indications. 2. Lumbar spondylolisthesis with disc herniation and spinal stenosis. 3.l4, l5 vertebral body or attachment due to various causes of surgical resection after affecting vertebral stability. 4. Severe osteoporosis should not be treated with pupillary slippage. Moderate patients should be treated with improved surgery. Contraindications 1. s1 ~ 2 severe recessive spina bifida and posterior fornix should not be used for this operation. Preoperative preparation 1. Take positive, lateral, oblique x-ray films, carefully observe the extent of recessive spina bifida, anterior humeral epiphysis, bone bridge, vertebral body deformation and degree of displacement, as a choice of surgery and need to be taken during surgery The basis for the measures. Note that the transitional vertebra helps in intraoperative positioning. 2. Contact intraoperative video surveillance. 3. iv degree slippery need to prepare the abdomen and waist skin when anterior lysis of the vertebral body. 4. Preoperative exercise in bed to urinate, indwelling catheterization on the day of surgery. Surgical procedure 1. Position: Prone position, hip flexion, knee flexion 45°. If you need to make a solution to the road, first supine, then change to prone position. The abdominal aorta bifurcation was revealed, and the sacral artery and vein were found, and the ligation was cut. The anterior fascia fascia is cut, the vertebral body can be touched, and the intervertebral disc and anterior longitudinal ligament under the vertebral body are removed. If the anterior inferior margin of the vertebral body is hyperplasia, affecting the reduction, the hyperplastic bone should be removed. The anterior superior marginal hyperplasia of the next vertebral body is also treated. Attach the vertebral body to the periosteal stripper and try to lift the vertebral body. If it can move, it means that it has reached the goal. You can close your abdomen, turn over, and walk in the back. 3. Posterior incision, revealed: the median incision in the lumbosacral region, revealing l4 ~ s2 lamina, until the bilateral joints outside the joint. If l4 slips, it reveals l3 ~ s2 (see the posterior side of the spine for details). 4. Excision of the detached vertebral lamina: the position of the control x-ray film, the spine of the sliding and dissecting vertebrae is floating, that is, its lamina. The lamina is mostly sloped or even upright, and must be identified. The descending isthmus is not connected to the following laminae, including the inferior articular process when needed. Because the vertebral body is slippery, the dural sac and nerve roots are also displaced and compressed, and care should be taken to avoid damage when removing the lamina. There is often a lot of fiber and cartilage hyperplasia in the isthmus of the isthmus, and the hypertrophic ligamentum flavum compresses the nerve root, and the decompression needs to be completely removed. At this point, the dural sac can be seen, and the front of the vertebral body is moved forward with a slight pull to reveal the vertebral body forward, which is stepped like the next vertebral body, and the nerve root is relatively tight. 5. Pin positioning: First, the nerve roots are found on both sides of the posterior margin of the vertebral body, and each is pulled outward. A Kirschner wire was inserted inside the slipping vertebral body on the inner side to observe the inclination of the slipping vertebral body and as a guide for the arching pin. Then, on the transverse line of the vertebral column, the outer edge of the papillary process, and the sub-protrusion, a small hole is drilled, and the Kirschner wire is inserted through the hole, parallel to the guide needle of the disc, and inclined forward by 15°. Direct access to the vertebral body. The lateral position of the lumbar spine was used to observe the position and relationship of the two steel needles. If it is substantially parallel to the upper edge of the vertebral body, the screw can be screwed in this direction. If the requirements are not met, it is necessary to measure the angle of the needle that needs to be corrected according to the guide needle of the disc, and re-determine the direction of the screw. At the same time, the depth of entry of the K-wire is measured to guide the depth of the vertebral body into which the screw enters. 6. Screw in the pedicle screw: remove the pedicle steel needle, according to the satisfactory direction of the bow steel needle displayed by the x-ray film, or according to the measured angle to be adjusted by the disc steel needle, use a square socket wrench The pedicle screw is screwed into the pedicle and vertebral body, typically at a depth of 3.5 to 4.0 cm. The step of screwing in the screw is required to be completed once. If the screw is screwed in, the direction is wrong, and the second direction is required to be screwed in, which will weaken the holding force of the bone on the screw and cause looseness. The depth of the screw into the vertebral body is required to be more than 80% of the anteroposterior diameter of the vertebral body. 7. Insert the steel plate handle into the pupil: first reveal the hole after s1, and electrocoagulate to stop bleeding. Check the upper edge of the bone for defects. If there is a defect, the triangle joint of the steel plate will have no support point, and should be replaced with s 2 hole. First, use the pupil stripper to closely adhere to the posterior inferior edge of the pupil to extend into the iliac nerve root and blood vessels, and reach the anterior sacral hole. The slippery steel plate handle is slowly inserted along the peeling path, and the front hole is pierced, and the triangular protrusion is pressed against the upper edge of the rear hole. After inserting one side, insert the other side. After the squat, the shape of the hole is different and the size is different. When necessary, the lower edge and the side edge can be properly trimmed and enlarged to be able to accommodate the shank, but the upper edge cannot be broken, so as not to weaken the bearing capacity of the fulcrum. After the handle is properly inserted, the camera should be inspected to confirm whether the shank end is hooked to the lower edge of the anterior humeral hole; at the same time, the direction, depth and position of the pedicle screw should be observed and adjusted to meet the requirements. Note that the steel plate is divided into left and right and cannot be misplaced. 8. Reset the slipping vertebral body: After taking the x-ray film to show that everything is proper, you can try to put the long hole of the steel plate on the pedicle screw, check the angle between the steel body and the handle, and the distance between the body and the lamina must be at least 2 times the vertebral slip distance, can be adjusted with a bender. Then screw on the reset nut and use a socket wrench to alternately apply the nut on both sides. For severe spondylolisthesis, the spine expander can be used to open the intervertebral space, and the iliac bone reducer can be inserted into the lower disc of the vertebral column to help reset. Sometimes, the proximal part of the isthmus and the transverse process can be moved forward to the front of the lower vertebrae, which affects the reduction, and the upper facet can be partially removed. The vertebral body to be slipped is gradually reset until the stepped shape of the vertebral body completely disappears. At this time, it can be seen that the dural sac and the nerve root become straight and loose. After taking the x-ray film to confirm that the reset is satisfactory, put on the fixing nut to strengthen the fixing to prevent loosening. 9. Interbody fusion: the dura mater is gently pulled to the left and right, the lower disc of the spine is exposed, and the partial disc and the upper and lower vertebral bodies on the left and right sides are cut by a special circular saw. Until the cancellous bone. If the bone resection is insufficient, use a circular chisel to enlarge. The circumcision is about 2.5 to 3 cm deep into the vertebral body, so it should not be too deep, so as not to damage the abdominal aorta and inferior vena cava in front of the vertebral body. Then, in the posterior part of the humerus, use a large ring saw to take a 2.5 to 3 cm long cylindrical bone block, implant it into the intervertebral ring saw hole, perform fusion between the vertebral bodies, and smash the bone graft to the back of the vertebral body. Leveling, does not cause the bone to protrude into the spinal canal. 10. Stitching: Thoroughly stop bleeding, rinse the wound, take a fat sheet to cover the epidural space and wrap around the nerve root, and fix its edge to the surrounding soft tissue. The hose is vacuumed and drained by a small incision next to the incision. Sewing layer by layer.