Zero-Profile Stand-Alone Cages Versus Traditional Cage-and-Plate Constructs in Single and Multi-Level Anterior Cervical Discectomy and Fusion: A Propensity-Matched Analysis Using Validated Fusion Assessment Methods.

ObjectivesStand-alone (SA) and anterior cage-and-plate (ACP) have been studied in anterior cervical discectomy and fusion (ACDF). However, fusion assessment methods vary and existing studies are not propensitymatched and often lack patient-reported outcomes (PROMs). We compare fusion rates between propensity-matched single- and multi-level SA versus ACP using a method validated by intraoperative motion testing during revision surgery. We also compare sagittal alignment, perioperative outcomes, and PROMs.MethodsPatients >18 years who underwent primary ACDF were included. 2:1 propensity score matching was performed. Fusions were assessed using 1 year computer tomography and flexion/extension radiographs via validated fusion assessment methods. ALOD was assessed at least 6-months postoperatively. Sagittal alignment was assessed at preoperative, short-term postoperative (2-6 weeks), and long-term postoperative (6 months or more) time points. PROMs, operative time, blood loss, dysphagia, and complications were analyzed.Results153 patients (51 SA) were included after matching. There were no differences in fusion rates overall (P = .662), or by number of surgical levels. There were no differences in ALOD at upper or lower levels, nor was there a difference in ALOD grade. Regarding segmental lordosis, overall lordosis, T1 slope, TS-CL, and PROMs (NDI, SF-12 PCS, VAS neck and arm), there were no differences at preoperative or any postoperative time point. Operative time and blood loss were greater in the ACP cohort, with no differences in complications or postoperative dysphagia.ConclusionsFusion rates, PROMs, radiographic outcomes, complications, and dysphagia rates were all comparable following single and multi-level ACDF between SA and ACP.