The surgical stabilization of rib fractures helps maintain chest wall stability and reduces respiratory complications. This study aimed to identify the key biomechanical parameters for evaluating the stability of rib fracture fixation using finite element analysis (FEA) and compare four rib fixation configurations-intramedullary rib splint (IRS), locking plate (LP), claw-shape plate, and intrathoracic plate (IP)-using biomechanical analysis. Forty patient-specific FEA models of fourth-rib fractures were constructed using the computed tomography scans of 10 patients. Maximum implant displacement (MID), maximum rib fracture displacement, maximum implant von Mises stress (MIVMS), maximum rib von Mises stress, maximum rib strain, and maximum interfragmentary gap (MIG) were assessed by simulating the anterior and posterior loads on the ribs during postoperative frontal collision. The fixation stabilities were evaluated using entropy scores. MIVMS, MIG, and MID exhibited the highest weighting coefficients. Lateral cortical fixation strategies, particularly LP configuration, demonstrated superior biomechanical performance compared with IRS and IP systems. The composite score of the LP was significantly higher than that of the other modalities. MIVMS, MIG, and MID were identified as critical parameters for evaluating the rib fracture fixation stability, and the lateral cortical fixation strategy (LP) enhanced the structural stability of rib fracture fixation.
Keywords: biomechanics; finite element analysis; rib fracture; surgical stabilization of rib.