3D printed spinal fusion devices: Technological breakthroughs, clinical challenges and intelligent future

Three-dimensional (3D)‑printed spinal fusion devices have emerged as a transformative solution to the limitations associated with conventional spinal implants, including mechanical mismatch, limited biocompatibility, and insufficient bioactivity. This review summarizes recent advances in the development of 3D‑printed spinal fusion devices and discusses how additive manufacturing technologies address key shortcomings of traditional implants. Recent evidence demonstrates that additive manufacturing enables the fabrication of patient‑specific implants with optimized porous architectures—such as triply periodic minimal surface (TPMS) structures—that closely replicate the mechanical characteristics of native bone while promoting osseointegration. In addition, the integration of bioactive materials and functional coatings enhances biological performance and introduces multifunctional capabilities, including localized drug delivery and improved interface stability. Another important development is the application of artificial intelligence (AI) in implant design and surgical planning, enabling personalized structural optimization and biomechanical matching. Overall, the convergence of 3D printing and AI is accelerating the transition toward intelligent and personalized spinal implants with the potential to substantially improve surgical outcomes. However, widespread clinical translation will require long‑term safety validation, cost reduction, and the establishment of standardized regulatory frameworks.