Comparison of the effects of different fixation methods on open-door side in posterior expansive open-door laminoplas-ty

Abstract

Objective To investigate the clinical outcome and complications of different types of expansive open door laminoplasty in cervical spondylotic myelopathy. Methods From December 2008 to June 2012, 221 patients with cervical spondylotic myelopathy treated with expansive open-door laminoplasty were divided into micro-titanium plate fixed group (96 cases), wire hanging fixed group(66 cases), anchor suspension fixed group (59 cases). The clinical outcome was evaluated in-cluding JOA score, operation time, bleeding volume, spinal cord pressure (a/M), cervical range of motion (ROM), open door an-gle, posterior shift distance of spinal cord and postoperative complications. Results All patients were followed up for more than 2 years. There were no significant differences in general condition, operation time, intraoperative blood loss, preoperative and post-operative 2 years JOA score, JOA score improvement rate, spinal cord shift distance, spinal cord compression among three groups; In the incidence of C5 nerve root paralysis, there was no significant difference between the silk suspension fixation group (12.1%) and the anchored suspension group (11.9%). The incidence of C5 nerve root paralysis for microplate fixation group (2.1%) was sig-nificantly lower than that of the silk suspension fixation group and anchored suspension fixation group, and the difference was sta-tistically significant. There was no significant difference in the fusion rate between the 3-month and 6-month portal arteries in the group of silk suspension fixation group(65%, 82%) and anchor fixation group(61%, 82%). The fusion rate of the microtiter plate fix-ation group(90%, 98%) was significantly higher than that of the silk suspension group and the anchorage group at 3 months and 6 months after operation. There were no significant differences in the incidence of recurrence, the total amount of cervical spine loss and the incidence of axial symptoms after 6 months of operation in the suspension group and the anchor suspension group. The in-cidence of occlusion, the total amount of cervical spine loss and the incidence of axial symptoms were significantly lower in the mi-cro titanium plate fixation group than those in the silk suspension group and the anchorage fixation group, the difference was statis-tically significant. Conclusion Using micro-titanium plate to fix the side of open door could achieve full spinal cord decompres-sion and access to satisfactory neurological improvement rate. At the same time, compared with the traditional silk or anchor sus-pension, the use of micro-titanium plate is more conducive to the door axis bone healing, prevent the occurrence of reclosing, sig-nificantly reduce the loss of postoperative cervical range of motion, and reduce the incidence of axial symptoms with the satisfac-tion of the clinical outcome. Key words: Cervical vertebrae; Spinal cord compression; Decompression, surgical; Postoperative complications; Radicu-lopathy