Hybrid triad provides fracture plane stability in a computational model of a Pauwels Type III hip fracture

The study utilized finite element method to determine displacements and stresses in a set of Pauwels Type III femoral neck fractures repaired using 3 techniques (cannulated screws (Triad), sliding hip screw (SHS), and a Hybrid (SHS + cannulated screws). The research found that shear displacement doubled between the 65° and 75° fracture angles regardless of fixation construct. The SHS alone was the least stable construct, with highest construct stresses and shear displacement along the fracture plane. The stability of the Hybrid and Triad constructs were similar, but stress in the Hybrid was lower suggesting it would provide a higher load to failure than the Triad.

本研究采用有限元法（Finite Element Method），对采用3种内固定技术修复的一组Pauwels Ⅲ型股骨颈骨折（Pauwels Type III femoral neck fractures）的位移与应力情况进行分析，3种技术分别为Triad型空心螺钉（cannulated screws）、滑动髋螺钉（sliding hip screw，SHS）以及混合固定（SHS+空心螺钉）。研究发现，无论采用何种内固定装置，当骨折角度介于65°至75°之间时，剪切位移均会翻倍。仅采用滑动髋螺钉的内固定装置稳定性最差，其固定装置应力与骨折面剪切位移均为最高。混合固定与Triad型空心螺钉固定的稳定性相近，但混合固定的应力水平更低，这表明其失效载荷高于Triad型空心螺钉固定。