Short-fiber reinforced thermoplastics, popular due to their strength, lightness, and cost-effectiveness, are often manufactured using injection molding to create complex parts with dispersed short fibers. However, failure in these materials is complex, involving mechanisms like fiber cracking and plastic deformation. Current models for damage and failure are either macroscopic or simplified. A new method tackles this challenge by evaluating stiffness using continuum damage mechanics with a multistep homogenization approach. This new method is called “Mean Field Homogenization”. This approach involves a two-stage process: first, the fibers are split into groups (grains). Then, mean-field homogenization is employed within Abaqus using a UMAT subroutine to average stiffness across these phases, followed by overall homogenization. This use of mean-field homogenization Abaqus simplifies the modeling of the composite's intricate geometry. The method was validated through testing on a distal radius plate. Calibration was achieved through experiments, and the simulation was performed using Abaqus finite element software. It's important to note that the Abaqus short fiber damage mean field homogenization process was implemented within Abaqus through the INP code.