Three-Dimensional Printed Anterior Cervical Standalone Combined Cage-Plate-300 Consecutive Medical Implants.

Abstract

Objective: The primary objective was to investigate the perioperative parameters and clinical outcomes of a novel three-dimensional (3D) printed titanium interbody spacer and integral screws. The secondary objective was to compare the survivorship rate of the 3D-printed titanium integrated spacer (3D-printed spacer group) with that of a polyether-ether-ketone (PEEK) integrated spacer (PEEK group) and traditional allograft spacer combined with an anterior cervical plate (control group).

Study design: This is a retrospective study comprising 157 consecutive patients (representing 300 surgical levels) investigating the perioperative and clinical outcomes of a novel 3D-printed titanium integrated spacer for anterior cervical diskectomy and fusion (ACDF).

Methods: A consecutive series of 157 patients (N = 300 surgical levels) presenting with cervical radiculopathy, myelopathy, or spondylosis underwent ACDF with the 3D-printed titanium spacer. Perioperative outcomes including surgical time, estimated blood loss, length of hospital stay, and number of surgical levels were collected. Clinical outcomes including the American Spinal Injury Association neurologic impairment score and Neck Disability Index (NDI) were measured preoperatively and postoperatively. Survivorship was defined as no failures, no anterior revision surgeries, no instrumentation removals, and no subsidence requiring surgery.

Results: The mean surgical time for the 3D-printed spacer group was 126.3 ± 34.0 minutes, the estimated blood loss was 85.9 ± 30.5 cc, and the length of hospital stay was 1.5 ± 1.4 days. Surgical levels were distributed as follows: 33.8% single-level, 42.7% two-level, 21.6% three-level, and 1.9% four-level ACDF procedures. 98.7% of patients in the 3D-printed spacer group reported improved American Spinal Injury Association scores. The mean NDI preoperatively was 37.2 ± 18.7, and the mean NDI postoperatively was 21.2 ± 18.3, with 58.6% of patients reporting NDI improvement of 15% or greater. Survivorship was observed in 97.4% of patients in the 3D-printed spacer group, 98.0% in the PEEK group, and 93.3% in the control group (chi-square analysis: X2 [1, N = 1529] = 16.9, P = 0.0002).

Conclusion: A novel 3D-printed titanium spacer with integral screws for ACDF demonstrated improved survivorship rates compared with the traditional allograft spacer and anterior plate. Among 157 patients, only two required supplemental posterior fixation, one required removal for excessive kyphosis and were successfully revised with a 3D-printed corpectomy spacer, and one had notable subsidence at 6 weeks postoperatively (4 total failures based on the survivorship criteria; 97.4% survivorship success rate (153/157 patients)). Not a single case of neurologic progression was observed in the 3D-printed spacer group-no iatrogenic progressive radiculopathy nor myelopathy, unlike the control group.