Synthetic 3D Printed Tibial Plateau with Gradient Material Properties for Biomechanical Accuracy

Damiano Coato^1,2Gianmarco Dolino^1,2Alice Berardo^2*Elisa Belluzzi^3,4Assunta Pozzuoli^3,4Pietro Ruggieri⁴Emanuele Luigi Carniel²Paolo Gargiulo¹

• ¹Institute of Biomedical and Neural Engineering, Department of Engineering, Haskolinn i Reykjavik, Reykjavík, Iceland
• ²Department of Industrial Engineering, Universita degli Studi di Padova, Padua, Italy
• ³Musculoskeletal Pathology and Oncology Laboratory, Department of Surgery, Oncology and Gastroenterology (DiSCOG), Universita degli Studi di Padova, Padua, Italy
• ⁴Department of Orthopedics and Orthopedic Oncology, Department of Surgery, Oncology and Gastroenterology (DiSCOG), Azienda Ospedale Universita Padova, Padua, Italy

Introduction: This study presents the design and fabrication of a synthetic 3D printed tibial plateau, complete with tibial cartilages, developed to replicate the mechanical behavior of its natural counterpart. Methods: Patient-specific anatomical data were used to design the model, which was fabricated using advanced PolyJet™multi-material printing. Gradient material properties were integrated within the construct to reproduce the stiffness variations observed in native cartilage. Three different material mixes were developed and tested under indentation loading, and the optimal configuration (Mix 3) was selected based on its mechanical fidelity to biological tissue. Results: Mix 3 successfully reproduced the regional stiffness variations of native tibial cartilage. The instantaneous modulus (IM) of the synthetic cartilage closely matched that of the biological sample, with values of 3.19 ± 1.95 MPa vs 3.31 ± 2.33 MPa in the lateral compartment and 3.71 ± 1.38 MPa vs 3.72 ± 2.56 MPa in the medial compartment. Statistical analysis confirmed that most regional comparisons showed no significant differences (p > 0.05), supporting the strong mechanical agreement between synthetic and native cartilage. Conclusion: This study demonstrates the potential of Digital Anatomy materials produced with PolyJet™technology as a viable method for 3D printing anatomically and mechanically accurate models of the human tibial plateau. Overall, this approach provides a reproducible and ethically sustainable alternative to biological specimens, with implications for preclinical testing, implant design optimization, and the advancement of high-fidelity surgical training models.