ABSTRACT

It is anatomically feasible and potentially therapeutic to reconstruct a defective pelvis ring with antogenous long bones after hemipelvic amputation, but the biomechanical characteristics of the surgery are unclear to doctors and researchers. The objectives of this study were to analyze the stress distribution of two hemipelvic reconstruction surgeries using the finite element (FE) method and to find which surgery gave a more favorable outcome. An FE model of the intact pelvis was constructed through sequenced computer tomography (CT) images and validated with an in vitro experiment. Two operative schemes, the ischiadic tuberosity being replaced with the femur condyles or the tibial plateau, were modeled based on the intact model. A normal sitting posture was simulated, and von Mises stresses were calculated and compared among the three models. From a biomechanical perspective, reconstruction with the femur condyles should be considered preferential. In planning the operation, screws of larger than normal diameter should be used and their rigidity decreased to reduce the incidence of stress shielding.