Research status and clinical application of cervical pedicle screw fixation Xiao Xiaodong Zhang Yu 1 is currently seen from the trial and clinical results. Posterior pedicle screw fixation is superior to the stability of the spine. Since the fixation of lumbar pedicle screws in the 1990s, the technique of cervical pedicle fixation has gradually developed. Due to the complex anatomical relationship around the cervical pedicle, this technique is difficult to popularize. In order to safely use this fixed technique, in recent years, a large number of studies on the morphology and mechanics of the cervical pedicle have been done at home and abroad. And made many useful suggestions. It is summarized as follows.
1 Anatomical study Many scholars 1 used cadaver specimens on the outside of the pedicle, with a corner of 1 person. Sagittal 84. The vertebral arch seems to have undergone a lot of research.
1.1 pedicle abduction angle This angle is the horizontal surface of the pedicle between the pedicle and the midline is not a regular cylindrical specimen according to the measurement method is not the result of the results of the various scholars have a certain difference 1. General, 2 outside The angle of the exhibition is the smallest, the maximum is 04, and the direction of entry of the screw is gradually changed to 07. If it is coaxial with the pedicle, it can avoid damage to the surrounding nerve vessels. In the actual operation, according to the position of the cervical vertebra at the time, the direction of the modified nail should be observed. The height of the pedicle is 2, the height is 6877.36, 3, and the average is the maximum at the minimum of 04 at 6, from 03 07. Gradually, add 135. This measurement is related to the diameter of the fixing screw.
14 The length of the pedicle is measured in two segments, from the posterior vertebral cortex to the posterior margin of the vertebral body, 03, from the 3,7 joint posterior cortex to the posterior margin of the vertebral body between 13.815.6 claws 3 It is the length from the posterior vertebral cortex to the anterior edge of the vertebral body, between 29.7 and 3.1. This measurement is tied to the length of the anti-set screw.
2 Determination method of the nail insertion point Because of the difference in the shape of the cervical vertebra, the determination method of the nail insertion point of different sections is slightly different.
According to the anatomical positioning method of 2.12, the pedicle screw fixation method has a certain difference between the male and female in the inner edge of the 5 spinal canal under the horizontal line of the vertebral plate. The sagittal angle of the male 1.2 pedicle is the sagittal angle of the pedicle axis and the plane of the vertebral body on the longitudinal section. 8.5. The vertebrae surface is zero degree. The angle above is positive, the following is negative from 0307. It is 580778.714.84.14.13.4, which can be bamboo. From the sagittal angle of 07, the sagittal angle from the largest to +6 is the smallest. However, the difference between foreign and domestic measurement results is larger. 6. The abduction angle of the pedicle. The direction of the sagittal angle is the inclination of the drill bit to the head 20, the tail and the midline abduction 307. But 171 suggests that it is best to expose the inner upper part of the pedicle, under direct vision or with nerves The root is peeled off and the screw is the most reliable.
The pedicle screw fixation technique of 20306 is based on the posterior partial anatomical landmark of the lateral side of the cervical vertebra to guide the insertion point to the center of the posterior articular surface of the articular surface, which is close to the edge of the superior vertebral body joint. The angle of the nail is about 3040. The final positioning is based on the intraoperative perspective. 2 Use the line of the line to make the vertical line. The point of the nail is located at 1.626 from the vertical line of 4,641, and the final point of the nail is determined by the intraoperative photo observation.
2.327 of the push. Root screw fixation technique 7 The insertion point is the midpoint of the articular surface to the 3 fixation technique. The pedicle screw fixation was successfully applied without neurovascular injury. There were also no false joints during the 1222 months of follow-up.
The authors have different opinions on the fixed method. Domestic author 3 believes that the screw diameter of 25,034445 abduction 4567 abduction 3 drilling is appropriate. 02 pedicle is not suitable for pedicle screw fixation.
Because the pedicle is very hard for a drill or awl, during surgery. It is likely to be more powerful. If slippage occurs, it will be extremely dangerous.
Therefore, a 2-claw cobalt head can be used for drilling. Using the electric drill to move at (3), there is a way to choose the actual operation. It is based on local anatomical positioning, ie as a joint as described above. The upper 1 edge line of the 7-segment is determined to determine the entry point and the direction of the nail insertion; it is determining the entry point. Before the direction, the fixed segment of the lamina is cut into 1 life as a record of 07. Then the 06.7 plate is partially removed, and the right angle nerve stripper is used to directly detect the pedicle or under direct vision; The calculation of ttlflW.f is still in the experimental stage. The completion of the final technology is likely to be a comprehensive approach.
4 Biomechanical studies The ideal spinal internal fixation system should be able to increase its stability from the axial direction of the spinal motion. The anterior cortical bone of the cervical vertebral body is not as strong as the posterior bone structure of the vertebral body. In cases of posterior injury or anterior and posterior injuries. Even if the screw enters the vertebral vertebral pedicle dimension of the vertebral body. The article accurately measured the cervical transverse process and spinous processes to provide a reliable basis for clinical work. In the traditional cervical vertebra injury, the simple anterior posterior fixation can only provide a certain stability to the flexion motion, but the stability to the rotational motion is poor. Ruler 03; etc. 5 compared the anterior lumbar bone graft. The biomechanical stability of seven different cervical reconstruction methods, such as anterior passer, self-locking titanium plate fixation, posterior wire fixation, posterior pedicle screw fixation and anterior and posterior fixation. Conclusions, the stability provided by the column fixation of cervical pedicle screws. More than the traditional cervical fixation system. Especially in terms of torsion and over-extension. Even when the current column or column is severely damaged, the overall stability provided by pedicle screw fixation is almost the same as that provided by the anterior plate combined with the posterior wire fixation. However, because they are based on the experimental model of the calf cervical spine, the significance of these data on the human model needs to be further explored.
5 clinical application 51 surgery; 4 syndrome has no clear indications for cervical pedicle screw fixation. Fixation of the vertebral screw column can increase the stability of the spine. Therefore, if you want to choose this fixed surgery, you must carefully yl. before surgery! itt1Tiil, Ba6JalvH1; difficulties in the placement of screws during surgery 41.
Because the pedicle is the strongest joint on the vertebral body, when the posterior structure of the spine is not suitable for fixing with steel wire or the like. The fixation of the vertebral body through the pedicle screw provides the column with a stable and strongest posterior fixation of the spine. Generally speaking. This fixation method is suitable for the following situations such as the slide. Degenerative arthritis infection after unstable multi-segment laminectomy after tumor injury and iatrogenic cases of cervical deformity reconstruction 161.
The greatest risk of 52 complication of cervical pedicle screw surgery is the damage of spinal nerve root and vertebral artery. Because there are few reports of cervical pedicle screw fixation.
The comorbidities are still not fully understood. According to 8. Bar et al. 617 cases of lumbar pedicle screw fixation of chronic nerve root injury 23. Screw fracture 29; intraoperative complication was 9.6, postoperatively occurred 17.8 cervical vertebrae pedicle screw placement needs to fully understand And understanding the morphological characteristics of pedicles.
Only in this way can the screws be accurately fixed in a satisfactory situation. Before the surgical indications and their risks are sufficiently recognized, the surgical procedure and practice should be considered with great care, but whether these data can be adapted to the cervical spine remains to be studied.
As the last fortress of the human spine.
With the advancement of cervical pedicle morphology research, cervical pedicle screw fixation technology will gradually mature and be safe. Will be applied to the lumbar spine. It brings great benefits to the stability of the spine.
6 References 3 Sun Yu. Wang Zhiguo, Dang Geng Town, and so on. Cervical pedicles reported.
骶1 The case of the contralateral ectopic of the roots was reported in a case of Guo Yanfeng and Zhu Tianyue 2, male, 68 years old. Pain after a sprained waist 15 years ago. Better after bed rest. In the future, there will be seizures every year. After the rest and symptomatic treatment, there will be improvement. After 2 months of admission, there is no obvious cause of low back pain and gradually worsened. At the same time, when the numbness of the right foot is accompanied by pain, the right lateral position of the chest and knee can only be relieved, and the intermittent claudication distance is. The stool is normal.
The waist of the body is stiff, the left side is curved, the right side of the psoas muscle is tense, and the waist activity is obviously limited. 531 The tenderness between the spine and its sides is the weight on the right side. At the same time radiating to the outside of the right foot. Straight leg raising test 60+ on the right side. Left detection 40+. Strengthening test +, the right lateral foot hornworm is dull. Yu Weizhen translation, line 1 lumbar vertebrae hyperplasia. Lumbar spinal canal angiography has a contrast agent filling at the right side of the 31 nerve root sleeve, which is not abnormal. There was no significant change in the lateral oblique dural sac. The left nerve root of 181 was not abnormal. The soft tissue density at the right nerve root of 31 was not connected with the intervertebral disc and continued with the imaginary nerve root. The ventral dural sac was not deformed at the interval of 1.10. 81 under the joint hyperplasia, diagnosis of 531 disc herniation.
1 Department of Orthopaedics, Miyun County Hospital, Beijing 101500, China 2 Department of Orthopaedics, Peking University Hospital, 31 Department of radiance, root ectopic, Yin Yin, right 81 nerve, posterior root ganglion hypertrophy, ectopic spinal canal. The right 81 nerve roots were emitted from the left 31 nerve roots, and the 51 disk yellow space was traversed to the right side of the dural sac and crossed the dural sac into the right 81 nerve root canal. The posterior root of hypertrophic edema is stuck at the entrance of the root canal, and the 581 intervertebral disc is not prominent. Line 31 nerve root canal enlargement, 81 nerve roots after release. Close the wound. Postoperative nerve root symptoms disappeared.
The function is fully restored. There was no recurrence after 2 years of follow-up.
Discussion of the lumbosacral dysmenorrhea root deformity literature has reported the literature Liu review literature, the waist, nerve root deformity is divided into 9 categories, but 31 nerve roots opposite. After crossing the dura mater back to the side, there were few reports of symptoms due to ectopic spinal canal ectopic. It is very similar to the clinical symptoms caused by 581 disc herniation, which may cause misdiagnosis. In this case, at the entrance of the tube, 81 nerve roots and the posterior root edema were caused. Caused by venous congestion of the nerve roots and inflammatory mediators 14 pushed. Lu Yinglong. Wait a minute. A case report of abnormalities in the arc of the exhibition was reported in the Chinese Journal of Orthopaedics. 1994 2 Liu Wei, Wang Zhenhan. Zhou Shao took and so on. Lumbar sacral nerve root deformity. Chinese Journal of Spinal Ridge. 19944
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