Effect of anterior cervical decompression and internal fixation on sagittal parameters of the cervical spine using 3D printed intervertebral fusion cage

English Keywords:Cervical spondylotic radiculopathy  3D printed intervertebral fusion cage  Sagittal balance parameters

English Abstract:

  【Abstract】 Objectives: To explore the effect of 3D printed intervertebral fusion cage-assisteddiscectomy, decompression, fusion and internal fixationonpostoperativecervical sagittal balance parameters in patients with cervical spondylotic radiculopathy. Methods: A total of 76 patients with cervical spondylotic radiculopathy treated in our hospital from January 2017 to June 2018 were selected and divided into observation group (38 cases) and control group(38 cases) according to the table of random digits. There were 21 males and 17 females in the observation group , aged 42-62 years old, with an average of 51.7±3.8 years old, and 20 males and 18 females in the control group, aged 41-63 years old, with an average of 52.4±4.5 years old. Both groups were treated with intervertebral disc removal, decompression, fusion and internal fixation. Patients were implanted with ordinary allograft bone in the control group, and with 3D printed intervertebral fusion cage in the observation group . The operative conditions(operative time, intraoperative blood loss, length of stay) were compared between the two groups. The sagittal balance parameters (C2-7 Cobb angle, C2-7 SVA, T1 tilt angle) before operation, immediately after, 6 months after, and 1 year after surgery were compared between the two groups by anterior and lateral X-ray examination of cervical spine. Cervical spine function (JOA) scores of 6 months and 1 year after surgery were compared between the two groups. The fusion was evaluated by lateral radiographs of the cervical spine at 1 year postoperatively, and the fusion rate was calculated. The incidence of complications between the two groups was statistically compared. Results: Intraoperative blood loss was 45.73±5.27ml in the observation group and 62.15±7.38ml in the control group. In the observation group , the operative time was 84.29±6.11min, and the length of stay was 6.81±1.52 days. In the control group, the operative time was 105.34±12.04min, and the length of stay was 8.54±1.08 days. The differences between the two groups were statistically significant(P<0.05). In the observation group , the C2-7 Cobb angle was 26.15°±3.02°, the C2-7 SVA was 14.28±2.31mm, and the T1 tilt angle was 31.46°±1.83° immediately after surgery. They were 28.79°±4.03°, 12.60±4.24mm, 30.16°±1.64° at 6 months aftersurgery. They were 29.46°±5.11°, 11.31±3.70mm, 28.65°±2.02°, respectively, one year after surgery. In the control group, the C2-7 Cobb angle was 21.67°±2.59° immediately after surgery, the C2-7 SVA was 17.39±3.04mm, the T1 tilt angle was 32.78°±1.91°, and the 6 months after surgery were 23.76°±3.90°, 16.88±3.29mm, 31.58°±2.01°, respectively. One year aftersurgery, they were 25.28°±4.43°, 15.42±3.46mm and 30.46°±1.79°, respectively. The parameters of the observation group were better than those of the control group at each time point(P<0.05). The JOA scores of the observation group at 6 months and 1 year after surgery were higher than those of the control group(P<0.05). At one year aftersurgery, the fusion rates of both groups were 100%, and the complication rate of the observation group was 5.56%(2/36), and that of the control group was 11.76%(4/34), with no statistical significance(P＞0.05). Conclusions: Compared with the implantation of ordinary allogeneic bone blocks, the application of 3D printed intervertebral fusion cages in patients with cervical spondylotic radiculopathy can optimize the operation situation during the decompression, adjust significantlythe sagittal balance of cervical spine and improve the function of cervical spine.