ABSTRACT
Objective To compare and analyze biomechanical stability of Ethibond thread suture and threaded anchor for fixing inferior pole fracture of the patella using the finite element method. Methods CT images of the knee joint from a healthy adult volunteer were selected and the inferior patella fracture model was established, then the three-dimensional (3D) models of fracture fixation with Ethibond thread suture and threaded anchor were established. Stress and displacement distributions of each fixiation model at different knee flextion angles were analyzed. Results In the range of 0°-90°, as knee flexion angle increased, the maximum stress and maximum displacement also increased. At the same knee flexion angle, threaded anchor fixation had the highest stress level, and Ethibond thread suture had the lowest stress level and the most uniform stress distributions. The displacement deformation of Ethibond thread suture was the largest, and the displacement deformation of threaded anchor fixation was the smallest. Conclusions The maximum displacement of the seam suture around patellar tendon with Ethibond suture is relatively moderate, and its maximum stress is relatively small, which is a reliable method for fixing inferior pole fracture of the patella in clinic.