Comparison of the clinical effects of zero-profile anchored spacer (ROI-C) and conventional cage-plate construct for the treatment of noncontiguous bilevel of cervical degenerative disc disease (CDDD): A minimum 2-year follow-up

Abstract

Comparing the clinical and radiographic outcomes in anterior cervical discectomy and fusion (ACDF) using a zero-profile anchored spacer (ROI-C) or a conventional cage-plate construct (CPC) for treating noncontiguous bilevel of cervical degenerative disc disease (CDDD).Overall, 46 patients with 2 noncontiguous segments of CDDD, treated with ACDF from January 2011 to October 2015, were included in this study. ROI-C was used in 22 patients (group A) and CPC in 24 patients (group B). The clinical and radiographic outcomes and complications were compared pre- and postoperatively. All patients were followed up for at least 24 months after surgery.No significant difference was found in fusion rate, cervical curvature, height of fused segment (FSDH), intraoperative blood loss, and Japanese Orthopaedic Association (JOA), and Neck Disability Index (NDI) scores between the 2 groups. Group A had a shorter operation time and significantly lower incidence of dysphagia (3 and 24 months postoperatively) than group B (P < .001 and P < .05, respectively). Moreover, group A had a higher loss of FSDH than group B, but with no difference between the 2 groups (P > .05). Two cages developed subsidence in group A (4.5%) and 2 adjacent levels developed degeneration in group B (2,8%).ACDF with ROI-C device was superior to CPC for noncontiguous bilevel of CDDD because it avoided postoperative dysphagia and required a shorter operation time. Moreover, the clinical outcomes were comparable. Prospective trials with larger samples and longer follow-up are required to confirm the results.

Figure 1

A 53-year-old male. Sagittal plane of T2-weighted MRI scan (A) showed 2 noncontiguous segments of herniation (C3/4 and C5/6) compressed the posterior spinal cord, and the height of intervertebral space was reduced. The anteroposterior (B) and lateral (C) X-ray radiographs at 1 month postoperatively showed anterior cervical discectomy and fusion (ACDF) with zero-profile anchored spacers (ROI-C) at the corresponding levels.

Figure 2

A 44-year-old male. Lateral T2-weighted MRI scan (A) showed nonadjacent bilevel of disc herniation (C3/4 and C5/6) compressed the posterior spinal cord, and the height of intervertebral space was reduced. The anteroposterior (B) and lateral (C) radiographs at 1 month postoperatively showed anterior cervical discectomy and fusion (ACDF) with the traditional cage and plate at the corresponding segments.

Figure 3

Line graphs showed comparisons of clinical and radiologic results between Group A (ACDF with ROI-C device) and Group B (ACDF with cage-plate construct). Variable tendency of cervical lordosis (A) and disc height of fused segment (B). ACDF = anterior cervical discectomy and fusion, FU = follow-up, M = month, Postop = Postoperative, Preop = Preoperative.

Figure 4

A stacked graph showed the loss of FSDH in group A and group B during the follow-up period. The white block indicated the loss of FSDH from 1 month to 3 months postoperatively, and the black block indicated the loss of FSDH from 3 months postoperatively to the final follow-up. FSDH = Disc height of fused segment; M = month.

Figure 5

A 53-year-old male. Lateral plain films showedanterior cervical discectomy and fusion (ACDF) with ROI-C device at C3/4 and C5/6 at 1 and 3 months postoperatively (A, B), respectively. Reconstructed sagittal CT scan (C) showed bony fusion at the final follow-up.