A Comparative Study Of Implantation For Cervical Pedicle Screw By Paraspinal Muscle Approach And Traditional Approach

Objective Through comparative study on the injury of paraspinal muscle and nerve,the incidence rate of postoperative axial pain and the accuracy of the pedicle screw placement was also evaluated.Methods After the patients with cervical fracture dislocation and cervical instability were selected,the comparative implantation for cervical pedicle screw by paraspinal muscle approach and traditional approach were evalutaed.The operation time,incision length and bleeding volume surgery were checked.The changes of serum creatine kinase levels at preoperative and 1,3,5,7days after operation.All patients were followed up to evaluate the neck pain with visual analoque pain score(Visual analog scale,VAS score)preoperative and postoperative 1 day,12 months,at the end of the follow-up period.EMG evoked potential instrument was selected to evaluate intramuscular electromyography of the neck.Postoperative shoulder pain,stiffness and other symptoms were evaluated,then the incidence of axial pain were evaluated calculated.Results There was no significant difference between the two groups in preoperative VAS and preoperative CK(P>0.05).The scores of VAS in the paraspinal muscle approach group were significantly lower than those in the traditional approach group 3 days after operation,14 days after operation and 1 years after the operation.The difference between the two groups was statistically significant(P<0.05).Serum creatine kinase in two cases after second days were higher than that of before operation,but the increase in the CK value before and after the operation of the value of the traditional approach group was significantly higher than that of the paraspinal muscle approach group,and the differences were statistically significant(P<0.05).MRI score of the conventional approach group after 1 years was higher than that in the paraspinal muscles approach group,the difference was statistically significant differences(P<0.05)Conclusion The comparative study was centerd on the cervical pedicle screw placement in anatomical and clinical aspect of paraspinal muscle approach and the middle of the approach.In paraspinal muscle approach group,the skin and subcutaneous tissue were cutted and the trapezius,splenius capitis were seperated.Through the approach of multifidus and semispinal muscle of neck,cervical nerve posterior branch was esposed and protected on the surface of lateral cervical mass.And the lateral cervical mass was exposed by limited seperating the transversospinalis muscle around the position of cervical pedicle screw placement.Cervical pedicle screw was placed in the outside of the transversospinalis muscle and it was avoided tp stripping the transversospinalis on the cervical vertebral lamina.The integrality of structure and function were maintained to support the neck muscles and nerves after retaining neck,to prevent extensor contracture,to reduce the incidence of axial pain after operation.This study provides a new way to improve the traditional posterior median approach.At the same time in the transversospinalis muscle pedicle screw for lateral horizontal angle is relatively easy to avoid,due to insufficient level caused to pedicle screw into the trans-verse foramen by the angle,vertebral artery injury,and shorten the surgical incision with minimally invasive surgery.