Dega骨盆截骨术后最佳中心边缘角的三维有限元分析

目的:应用三维有限元技术评估发育性髋关节脱位(developmental dysplasia of the hip,DDH)患儿在Dega骨盆截骨术后不同中心边缘角(center-edge angle,CEA)状态下髋臼的应力分布,为术前的手术规划提供有参考价值的生物力学结果。方法:使用已建立的DDH患者髋关节三维有限元模型,以术后CEA27°为中间值,每3°为一个变量,在Mimics誖10.0软件的模拟手术模块分别构建7组髋臼截骨术后的模型。在单腿站立和双腿站立状态下测量不同CEA状态下髋臼的应力分布。结果:单腿站立情况下,CEA为24°、27°、30°和33°的术后模型患侧髋臼的峰值应力接近正常侧。双腿站立情况下,CEA为24°时双侧髋臼的峰值应力最为接近。结论:对于该患者而言,在7组术后CEA中,24°时患侧髋臼的峰值应力与健侧最为接近,可以认为是最佳的术后CEA。有限元技术能够为Dega手术的术前规划提供个性化的指导方案。

Optimization of the Center-edge Angle of the Acetabulumin a Dega Pelvic Osteotomy by Finite Element Analysis

Objective:To investigate the stress distributions of the acetabulum of the patient with developmental dysplasia of the hip (DDH) in different center-edge angles (CEA) following the Dega pelvic osteotomy using finite element technology, so as to provide valuable references for surgical planning of such patients.Methods:The three dimensional finite element hip model of the patient with DDH which had been established previously was used. Seven models were constructed in the surgical simulation module with the software Mimics 10.0. 27 ° was set as the middle value of postoperative CEA and 3 ° was taken as a variable set, then the stress distributions of the acetabulumwere measured in the standing position on one leg and two legs at different CEAs.Results:When standing on one leg, the maximal stresses of the affected acetabulums in the CEAs of 24 ° , 27 ° , 30 ° and 33 ° were close to those of the normal sides. Under two legs standing case, the maximal stress of the affected acetabulum came closest to that of the normal side when CEA was 24 ° .Conclusion:For this patient, in the 7 postoperative CEAs, the 24 ° may be thought as the best postoperative CEA, because the maximal stress of the affected side in the CEA of 24 ° was closest to that of the normal side. Finite element technology can provide personalized guide for preoperative surgical planning.