Böhme J, Steinke H, Huelse R, Hammer N, Klink T, Slowik V, Josten C
Klinik für Unfall-, Wiederherstellungs- und Plastische Chirurgie, Universitätsklinikum Leipzig.
Z Orthop Unfall. 2011 Jan;149(1):83-9. doi: 10.1055/s-0030-1250471. Epub 2010 Nov 15.
Instability of pelvic ring fractures is also caused by ligament disruption. Classifications are based on the major forces leading to fracture. Data from injury mechanisms as well as clinical and radiological criteria are used to determine the degree of instability. The major aim of all kinds of stabilisation is the anatomic reconstruction of the bony pelvic ring. The injured ligamentous apparatus is still ignored. Some clinical trials assume that soft-tissue injuries may be the reason for the poor patient outcome in "open book" pelvic ring fractures. The aim of the study was to develop a realistic finite element (FE) computer model to simulate "open book" fractures and predict injury-associated instabilities for osteosynthesis planning. PATIENTS/MATERIAL: We developed a realistic FE computer model of the pelvic ring based on CT data. With anatomic studies a computer model of the ligamentous apparatus was created and inserted into the pelvic ring to complete the bone-ligament complex. Numerical simulations were performed to identify the influence of single pelvic ligaments on the shifting at the intact anterior and posterior pelvic ring. Additionally, a biomechanical validated virtual crack simulation with anterior-posterior compression forces was undertaken to predict complex instabilities in "open book" pelvic ring fractures.
The pelvic ligaments have local and general stabilising functions. The sacrospinous and sacrotuberous ligaments are providing the vertical load transfer, whereas the ligaments of the iliosacral joint and the iliolumbal ligament are necessary for the horizontal load transfer. In "open book" fractures ligaments are ruptured stepwise from anterior to posterior. If the intraosseous and posterior ligaments of the iliosacral joint are intact, only single rotational instability along the ipsilateral iliosacral joint occurs. If the ligaments at the posterior pelvic ring are ruptured too, a second axis across both iliosacral joints was measured. In this particular case additional stabilisation of the posterior pelvic ring should be performed.
With numerical simulations, prediction of injury-associated instabilities is possible. Because of incomplete radiological data the implementation of patient-specific FE pelvic computer models into the clinical routine is still not realistic.
骨盆环骨折的不稳定性也由韧带断裂引起。分类基于导致骨折的主要作用力。来自损伤机制以及临床和放射学标准的数据用于确定不稳定程度。各种稳定治疗的主要目的是骨盆环的解剖重建。受损的韧带结构仍被忽视。一些临床试验认为软组织损伤可能是“开书样”骨盆环骨折患者预后不佳的原因。本研究的目的是建立一个逼真的有限元（FE）计算机模型，以模拟“开书样”骨折并预测与损伤相关的不稳定性，用于骨合成规划。
患者/材料：我们基于CT数据建立了一个逼真的骨盆环有限元计算机模型。通过解剖学研究创建了韧带结构的计算机模型，并将其插入骨盆环以完成骨-韧带复合体。进行了数值模拟，以确定单个骨盆韧带对完整骨盆环前后移位的影响。此外，进行了具有前后压缩力的生物力学验证的虚拟裂纹模拟，以预测“开书样”骨盆环骨折中的复杂不稳定性。
骨盆韧带具有局部和整体稳定功能。骶棘韧带和骶结节韧带提供垂直载荷传递，而骶髂关节韧带和髂腰韧带对于水平载荷传递是必需的。在“开书样”骨折中，韧带从前向后逐步断裂。如果骶髂关节的骨内韧带和后韧带完整，则仅沿同侧骶髂关节发生单一旋转不稳定。如果骨盆后环的韧带也断裂，则测量到穿过两个骶髂关节的第二条轴。在这种特殊情况下，应进行骨盆后环的额外稳定治疗。
通过数值模拟，可以预测与损伤相关的不稳定性。由于放射学数据不完整，将患者特异性有限元骨盆计算机模型应用于临床常规仍不现实。
