Effects Of Suture Anchor And Titanium Miniplate Fixation On Vertebral Lamina Fusion At Hinge Side After Cervical Expansive Open-door Laminoplasty

Objective: To investigate the effects of suture anchor and titanium miniplate fixation on vertebral lamina fusion at hinge side after cervical expansive open-door laminoplasty.Methods: 56 patients with cervical spondylotic myelopathy treated by using cervical expansive open-door laminoplasty were retrospectively studied,and were divided into suture anchor group(group A) and titanium miniplate group(group B), including 21 patients in group A, with 105 vertebral lamina opened, and 35 patients in group B, with 175 vertebral lamina opened. The changes of clinical symptoms, nervous functions and range of cervical motion were evaluated after operation in the two groups. Fractures of vertebral lamina at hinge side were evaluated by CT images 3 days after operation, and patients were divided into displacement fracture group and no displacement fracture group; CT images 3 months and 6 months after operation were used to evaluate bone fusion at hinge.Results: JOA scores were obviously improved 3 and 6 months after operation compared to those before operation(P = 0.039, 0.028), but no significant differences were observed in JOA scores and improving rate of nervous functions between the two groups(P>0.05). Compared to group A,ROM and VAS scores 6 months after operation were significantly higher in group B(P=0.031, 0.002). Total bone fusion rate in group B was higher than that in group A 3 months after operation(P=0.001), but not different 6months after operation between the two groups(P=0.088). Bone fusions were significantly higher in no displacement fracture subgroup compared to those in group A 3 months after operation(P = 0.005), but with no statistical significance between the two groups 6 months postoperatively(P = 0.585).Bone fusion rates of displacement fracture subgroup in group B were higher than those in group A 3 and 6 months after the operation(P=0.036, 0.024).Conclusion: Compared to suture anchor fixation, titanium miniplate fixation has better effects on stability and bone fusion at hinge after cervical expansive open-door laminoplasty, but the two methods are not different in improving nervous functions.