Jianyin LEİ, Pengfei DONG, Zhiqiang Lİ, Feng ZHU, Zhihua WANG, Xianhua CAİ

Biomechanical analysis of the fixation systems for anterior column and posterior hemi-transverse acetabular fractures

Objective: The aim of this study was to evaluate the biomechanical properties of commonŞxation systems for complex acetabular fractures.Methods: AŞnite element (FE) pelvic model with anterior column and posterior hemi-transverseacetabular fractures was created. Three commonŞxation systems were used to Şx the posterior wallacetabular fractures: 1. Anterior column plate combined with posterior column screws (group I), 2.Anterior column plate combined with quadrilateral area screws (group II) and 3. Double-column plates(group III). And 600 N, representing the body weight, was loaded on the upper surface of the sacrum tosimulate the double-limb stance. The amounts of total and relative displacements were compared between the groups.Results: The total amount of displacement was 2.76 mm in group II, 2.81 mm in group III, and 2.83 mm ingroup I. The amount of relative displacement was 0.0078 mm in group II, 0.0093 mm in group III and0.014 mm in group I.Conclusion: Our results suggested that allŞxation systems enhance biomechanical stability signiŞcantly.Anterior column plate combined with quadrilateral area screws has quite comparable results to doublecolumn plates, they were superior to anterior column plate combined with posterior screws.

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