摘要
目的结合股骨转子间骨折六部分分型法,利用有限元分析技术,建立股骨近端防旋髓内钉(proximal femoral nail antirotation,PFNA)、股骨近端经皮加压钢板(percutaneous compression plating,PCCP)分别固定不稳定性股骨转子间骨折的模型,对其进行力学分析,分析两种内固定方式的受力情况。方法建立股骨转子间骨折六部分分型模型,选取其中不稳定性骨折共6种骨折分型均分别以PFNA、PCCP进行固定。将正常股骨及12组股骨内固定结构模型进行有限元分析,得出其Von Mises应力图及Min Principal应力分布,分析内固定模型各重要部位的受力情况。结果不稳定性股骨转子间骨折经PFNA、PCCP固定后,其稳定性均有显著的提升。PFNA固定转子间骨折,降低了股骨近端外侧、内固定物远端内侧及外侧的股骨应力,虽股骨近端内侧应力有所增加,但增加幅度较小,约16%;相较于PCCP而言,PFNA螺钉固定处未见明显的应力集中情况,内固定结构本身应力约为115 MPa,属正常范围。PCCP固定不稳定性转子间骨折时,降低了股骨近端内侧、内固定物远端内侧及外侧的股骨应力,股骨近端外侧应力增加约45%,但尚在正常范围内;PCCP固定后,其螺钉处出现应力集中情况,应力集中约325~326 MPa,内固定物本身结构应力约为412~413 MPa,尚在正常范围内。结论 PFNA是治疗股骨转子间不稳定性股骨转子间骨折的有效手段,能用于治疗股骨转子间骨折六部分分型法中各分型骨折;PCCP由于对股骨近端内侧皮质支撑作用较弱,在用于固定三部分骨折(小转子破裂)及骨折粉碎程度更加严重的骨折时,易发生内固定物失效、髋内翻等并发症,在使用PCCP治疗不稳定性股骨转子间骨折时,应运用适当的方式,将股骨近端内侧壁进行有效固定,恢复其内侧支撑作用。
Objective Combined with the six-part classification method of intertrochanteric fracture, the unstable intertrochanteric fracture was fixed with PFNA and PCCP. A finite element mechanical analysis was carried out to investigate the mechanical stability of PFNA and PCCP in the treatment of unstable intertrochanteric fracture.Methods A six-part classification model of intertrochanteric fracture was established. Six types of unstable fractures were fixed with PFNA, PCCP. The Von Mises stress diagram and Min Principal stress distribution of normal femur and 12 groups of femoral internal fixation structure models were analyzed by finite element method, and the stability of the model was analyzed. Results The stability of unstable intertrochanteric fractures was significantly improved after fixation with PFNA and PCCP. And the stress of the proximal, distal and distal femur was decreased, although the medial stress of the proximal femur was increased. However, the increase was relatively small, about 16%. Compared with PCCP, there was no obvious stress concentration. The stress of internal fixation structure was about 115 MPa,which was in a normal range. PCCP fixed intertrochanteric fracture reduced the stress concentration of the medial proximal femur, distal medial and lateral stress of the internal fixation. Proximal lateral femoral stress increased by approximately 45%, but still in the normal range. Stress concentrations occurred at the screw( 325-326 MPa), and the structure of the internal fixation( 412-413 MPa) were still in the normal range. Conclusions PFNA is an effective method in the treatment of intertrochanteric femoral fractures and can be used in the treatment of each of the six parts of femoral intertrochanteric fractures. Because of its weak support to the medial femoral cortex, PCCP is prone to produce internal fixation failure, hip varus and other complications when used to fix three-part fractures( lesser trochanter rupture) and severe comminuted fractures. In the treatment of unstable intertrochan
作者
徐锴
李开南
XU Kai;LI Kai-nan(Affiliated Hospital of Chengdu University,Chengdu,Sichuan,610081,China)
出处
《中国骨与关节杂志》
CAS
2019年第7期498-503,共6页
Chinese Journal of Bone and Joint
基金
国家重点研发项目(2016YFC0105806)
四川省科技厅项目(2016FZ0066)
成都市科技惠民项目(2015-HM01-00221-SF)
关键词
股骨骨折
骨折固定术
内
有限元分析
Femoral fractures
Fracture fixation, internal
Finite element analysis
