The influence of different lamina opening angles in posterior cervical double door laminoplasty on the short-term efficacy of patients with cervical spondylotic myelopathy

English Keywords:Cervical spondylotic myelopathy  Posterior cervical double-door laminoplasty  Laminar opening angle  Short-term efficacy

English Abstract:

  【Abstract】 Objectives: To investigate the short-term clinical outcomes of different lamina opening angles during cervical laminoplasty with a double-door technique for patients with cervical spondylotic myelopathy(CSM). Methods: A retrospective analysis was conducted on 35 patients(18 males, 17 females, aged 61.49±11.27 years) with CSM who underwent cervical double-door laminoplasty between January 2019 and December 2023. All patients received C4-C6 double-door laminoplasty with partial or total laminectomy of C3 and partial laminectomy of C7. The follow-up period was 12.7±1.12 months. One week after operation, cervical CT was reexamined. The lamina opening angles were classified as <60°, 60°-68°, and >68°. Based on this, the patients were divided into 3 groups: group A(52.05°-58.53°), 13 patients, including 6 males and 7 females; Group B(60°-68°), 13 patients, including 7 males and 6 females; Group C(68.52°- 71.3°), 9 patients, including 5 males and 4 females. Clinical outcomes were assessed using the Japanese Orthopaedic Association(JOA) score, the visual analog scale(VAS) score for neck pain, and the recovery rate(RR) at 1 week, 1 month, 3 months, 6 months, and 12 months postoperatively. Statistical analysis was performed using SPSS software version 26.0. Results: The JOA scores were 9.81±1.03 and 15.92±0.64 in group A, 9.85±1.03 and 15.46±1.11 in group B, and 9.67±1.17 and 15.56±0.81 in group C, respectively at preoperaion and 12 months after opreation, showing statistically significant improvements within each group(P<0.05). However, no significant differences in JOA scores were observed between groups at any postoperative time point(P>0.05). VAS scores at various follow-up time points showed no significant differences between groups(P>0.05). Within-group pairwise comparisons showed that the VAS scores at 3, 6, and 12 months postoperatively were significantly lower than the preoperative values(P<0.05). The RRs at 12 months after operation were (74.79±6.78)% in group A, (69.25±12.26)% in group B, and （70.92±8.44）% in group C. Conclusions: In posterior cervical double-door laminoplasty for CSM, postoperative laminar opening angles ranging from 52.05° to 71.3° have no significant impact on short-term clinical outcomes.