Effect of Titanium Miniplate Fixation on Hinge Fracture and Hinge Fracture Displacement Following Cervical Open-Door Laminoplasty

Abstract

Background: Cervical spondylotic myelopathy is a neuromotor disorder responsible for functional limitations and decreased daily activities. Expansive open-door laminoplasty is the widely accepted procedure for the treatment of multilevel cervical spondylotic myelopathy. Among the various fixation procedures to secure the open lamina, miniplate fixation provides better clinical and radiological outcomes. However, the immediate effects on hinge fracture and hinge fracture displacement following miniplate fixation have not been proven until now. The purpose of our study was to elucidate the impact of cervical open-door angle on the status of spinal cord expansion and hinge fracture, hinge fracture displacement, and the role of implants used during surgery. Methods: For this retrospective study, 122 patients who had undergone surgery from September 2016 to November 2017 with preoperative and postoperative radiographs were enrolled. Clinical and radiological outcomes were assessed before and after surgery. Results: There were no significant differences in demographics, surgery time, blood loss, medical comorbidities, or perioperative and postoperative complications between 2 groups. The recovery rate and Nurick score before and at the follow-up show no statistical significance between the 2 groups, P value. .05 (P ¼ .672) and P. .05 (P ¼ .553), respectively. The statistical analysis shows that the mean hinge fracture in the miniplate group with a cervical open angle .308 was 2.42 6 1.68 and with a ,308 open angle, 0.05 6 0.23; whereas, in the anchor group the mean hinge fracture in .308 cervical open angle was 2.227 6 2.50 and in ,308 was 0.409 6 0.503. The results revealed statistical significance between 2 implant groups, P ¼ .024 in the aspect of hinge fracture displacement and implant used. Conclusion: Laminoplasty by titanium miniplate fixation holds the laminae securely, prevents hinge fracture displacement, and promotes spinal cord expansion better than suture anchor fixation.

Influence of fixed titanium plate position on the effectiveness of open-door laminoplasty for cervical spondylotic myelopathy

“…In many long-term follow-up studies over the past 2 decades, open-door laminoplasty has been proven to be an effective and simple surgical procedure for the treatment of multilevel CSM [ 2 – 4 , 6 – 8 ]. With the continuous development and innovation of surgical internal fixation devices, the fixation method of lamina has also changed from the initial suture suspensory to an anchor, and mini-titanium plates are widely used at this stage [ 3 , 4 , 9 ].…”

“…With the continuous development and innovation of surgical internal fixation devices, the fixation method of lamina has also changed from the initial suture suspensory to an anchor, and mini-titanium plates are widely used at this stage [ 3 , 4 , 9 ]. Through a clinical meta-analysis, Mo et al [ 8 ] found that compared with suture suspensory and anchor fastening, mini-titanium plate fixation can reduce the loss of range of motion, and the incidence of axial symptoms and C5 palsy is reduced. To maintain the opening state of the lamina, the silk thread can be sutured to the opposite articular capsule, and the anchor can be placed at the midpoint of the lateral mass on the hinge side.…”

“…With the widespread use of open-door laminoplasty, there are an increasing number of reports of the complications of hinge fracture [ 8 , 15 – 20 ]. Cho et al [ 16 ] performed CT scans on 23 patients who received open-door laminoplasty and found that 16 patients (69.6%) had one or more segment hinge fractures.…”

“…In the study by Lee et al [ 17 ], 28 (20.7%) laminae had hinge fractures in 135 opened laminae. It was previously reported that hinge fracture might be related to the thickness of the lamina [ 18 ], widths and deeps of the hinge gutter [ 19 ], opening angle [ 8 ], and hinge gutter location [ 20 ]. In this study, with the help of CT scanning, 11 patients (25.6%) in the lamina group and 5 patients (9.1%) in the lateral mass group were observed to have hinge fractures.…”

“…1 e and 2 d). The possibility of a hinge fracture was also observed by CT scan after surgery; that is, the continuous inner cortex was terminated, and possibly, the lamina was displaced [ 8 ]. Spinal cord drift distance (C): On the midline sagittal cervical MR image at 3 months postoperatively, the distance between the posterior edge of the C5 vertebral body and the midpoint of the spinal cord was measured pre- and postoperatively, C = C2–C1 [ 7 ] (Fig.…”