A novel medical trauma plate using bioactive ceramic composites - design and numerical modelling analysis

In traditional orthopaedics and traumatology, titanium alloy trauma plates (TATPs) are commonly used as internal fixators for fractured bones, typically with screws. However, this technique presents challenges: TATPs often require removal after healing due to non-degradability and potential corrosion, and their stiffness mismatch with bone can cause stress-shielding that may delay healing. To address these issues, a nacre-like biomimetic apatite-wollastonite composite has been introduced to develop a new trauma plate for orthopedic treatments and prosthetics. This bioactive ceramic composite trauma plate (BCCTP) is fully biocompatible with bone tissue, enabling permanent fixation without later removal. This study proposes an initial design for a biomimetic nacre-like BCCTP composed of apatite-wollastonite hydroxyapatite/poly(methyl methacrylate)-polyacrylic acid (AW-HA/PMMA-PAA). The composite exhibits an elastic modulus comparable to human bone, improving mechanical compatibility by reducing stress concentrations. A finite element method (FEM)-based construct model is established to optimize the structural design and geometric parameters of the BCCTP and its adhesive layer. The results indicate that the construct maintains compressive strains within the callus in the biomechanical range required for bone healing (2%-10%) across all loading cases, providing a foundation for next-generation bone fixation devices.