Statistical shape model-driven 3D-printed biomimetic intervertebral fusion cage with superior subsidence resistance

• We develop biomimetic interbody fusion cages driven by a statistical shape model. • Biomimetic interbody fusion cages exhibited exceptional anti-subsidence performance. • This anti-subsidence is due to the data-driven morphological fidelity design. • A bio-inspired and population-based design paradigm is presented. Degenerative disc disease (DDD) is a prevalent musculoskeletal disorder globally, causing substantial pain and suffering in patients. Spinal fusion surgery utilizing interbody fusion cages (IFCs) is the most commonly employed and effective clinical treatment, and it is considered the gold standard for the treatment of DDD. However, post-implantation cage subsidence remains a frequent occurrence, often resulting in complications, and continues to present a key challenge in the field. To address this issue, the biomimetic IFCs driven by a lumbar statistical shape model (SSM-IFCs) were developed and fabricated using polyetheretherketone (PEEK) and titanium alloy materials through 3D printing technology. Compared to the conventional IFCs (C-IFCs), PEEK-based biomimetic SSM-IFCs demonstrated a 76.5% to 82.7% improvement in anti-subsidence performance, while porous titanium alloy-based biomimetic SSM-IFCs exhibited a 79.4% to 119.5% improvement. These findings highlight the exceptional anti-subsidence performance of the proposed data-driven biomimetic SSM-IFCs and offer new insights for the development of next-generation intervertebral implants.