Stand-alone porous titanium cages for anterior cervical discectomy and fusion: clinical outcomes in a multicenter experience

BACKGROUND: Porous titanium cages have emerged as a promising alternative to traditional interbody materials in anterior cervical discectomy and fusion (ACDF), potentially enhancing osteointegration while maintaining mechanical stability. This multicenter study evaluates clinical and radiological outcomes following stand-alone ACDF using 3D-printed porous titanium cages. METHODS: This retrospective observational study included 120 patients (mean age 54.8 years) who underwent stand-alone ACDF across three tertiary spine centers. Clinical outcomes were assessed using the Numerical Rating Scale (NRS) and Short Form-12 (SF-12). Radiological outcomes at 12 months included fusion, subsidence, migration, and sagittal alignment parameters. Fusion assessment at 12 months was performed using CT or dynamic flexion/extension radiographs. RESULTS: At 12 months, interbody fusion was achieved in 106 patients (88.3%; 95% CI: 81.4%-92.9%). NRS scores significantly improved (mean reduction 4.2 points; p < 0.001), while SF-12 showed no significant change. Cage subsidence occurred in 7 patients (5.8%), with no cases of migration. Cervical sagittal alignment parameters remained stable over time, with no significant differences after correction for multiple comparisons. No significant associations were identified between preoperative variables and adverse radiological outcomes. CONCLUSIONS: Stand-alone ACDF with porous titanium cages is associated with high fusion rates, significant pain reduction, and low complication rates at 1 year. These findings support the use of porous titanium cages as a viable option in non-plating cervical fusion strategies, although further comparative studies are warranted to better define their relative performance. CLINICAL TRIAL NUMBER: Not applicable.