FracFormer: Fracture Reduction Planning With Transformer-Based Shape Restoration and Fracture Data Simulation

Accurate orthopedic fracture reduction planning is essential for ensuring successful postoperative recovery and improving patient outcomes. However, current automatic methods are challenged by the complex and irregular fracture geometries and the scarcity of annotated training data. To address these challenges, we propose a novel approach that integrates learning-based shape restoration and fracture simulation. A transformer-based model is developed, which utilizes patch-to-patch shape translation and recursive fragment registration to iteratively refine fracture reduction poses. A deformable fracture generation model (DFGM) combines statistical shape modeling with clinically representative fracture patterns to generate diverse and realistic datasets, reducing the dependence on annotated samples. Tested on extensive clinical data with hipbone, sacrum, and femoral shaft fractures, the proposed method achieved mean errors of 1.85 mm and 3.40°, outperforming both template-based and existing learning-based methods. In addition, models trained solely on DFGM-synthesized data presented strong generalizability to real clinical data. The ablation experiments demonstrate the effectiveness of the fragment-aware network pipeline and the synthesis steps. Finally, a cadaver study with ground truth derived from the pre-injury scan further validated the performance of the method.