ABSTRACT
Objective To study the influence of hollow screws with five kinds of spatial distributions on the fixation effect of femoral neck fracture. Methods Geometric models of femoral neck fracture with Pauwels type I, II and III were built by reverse engineering according to CT images of the femur. Based on the finite element analysis software ANSYS, the stress distributions of internal fixation, head side and stem side of femoral neck and the displacement distributions of the model fixed by different methods were obtained. Results For femoral neck fracture with Pauwels type I, II and III, the maximum stresses at head side of femoral neck were the inverted triangle fixation method, two-screw parallel fixation method, two-screw parallel fixation method, respectively. The maximum stresses at stem side of femoral neck were the inverted triangle fixation method, inverted triangle fixation method and two-screw parallel fixation method, respectively. The minimum stresses on the screws were the cross fixation method, and the minimum displacements of the model were double-supported fixation method. Conclusions The probability of screw deformation and fracture is the smallest for cross fixation method. Inverted triangle fixation method can provide a good mechanical environment for fracture site. For femoral neck fracture with Pauwels typeⅠ and Ⅲ, double-supported fixation method has the strongest ability to prevent femoral neck shortening. While for femoral neck fracture with Pauwels typeⅡ, cross fixation method has the strongest ability to prevent femoral neck shortening.
ABSTRACT
Circulating tumor cells (CTCs) detections have unique advantages in the real-time personalized medicine of patients with tumors.The rarity and heterogeneity of CTCs in peripheral blood pose great technical challenge for CTCs researches.Most of technologies for detecting CTCs have been developed to enrich CTCs by virtue of physical properties or specific biological features of the cells at first,then genotype or phenotype analysis are performed to count or characterize CTCs.Advances in molecular analysis of single cells enable CTCs detections to provide more accurate and comprehensive information.Biological processes during CTCs invasion and metastasis such as epithelial-mesenchymal transition and clustering should to be considered seriously to promote the clinical applications of CTCs detection.