Ridzwan Mohamad Ikhwan Zaini, Sukjamsri Chamaiporn, Pal Bidyut, van Arkel Richard J, Bell Andrew, Khanna Monica, Baskaradas Aroon, Abel Richard, Boughton Oliver, Cobb Justin, Hansen Ulrich N
Department of Mechanical Engineering, Imperial College London, London, SW7 2AZ, United Kingdom.
School of Mechanical Engineering, Engineering Campus, Universiti Sains Malaysia, Penang, 14300, Malaysia.
J Orthop Res. 2018 Mar;36(3):993-1001. doi: 10.1002/jor.23669. Epub 2017 Aug 21.
Proximal femoral fractures can be categorized into two main types: Neck and intertrochanteric fractures accounting for 53% and 43% of all proximal femoral fractures, respectively. The possibility to predict the type of fracture a specific patient is predisposed to would allow drug and exercise therapies, hip protector design, and prophylactic surgery to be better targeted for this patient rendering fracture preventing strategies more effective. This study hypothesized that the type of fracture is closely related to the patient-specific femoral structure and predictable by finite element (FE) methods. Fourteen femora were DXA scanned, CT scanned, and mechanically tested to fracture. FE-predicted fracture patterns were compared to experimentally observed fracture patterns. Measurements of strain patterns to explain neck and intertrochanteric fracture patterns were performed using a digital volume correlation (DVC) technique and compared to FE-predicted strains and experimentally observed fracture patterns. Although loaded identically, the femora exhibited different fracture types (six neck and eight intertrochanteric fractures). CT-based FE models matched the experimental observations well (86%) demonstrating that the fracture type can be predicted. DVC-measured and FE-predicted strains showed obvious consistency. Neither DXA-based BMD nor any morphologic characteristics such as neck diameter, femoral neck length, or neck shaft angle were associated with fracture type. In conclusion, patient-specific femoral structure correlates with fracture type and FE analyses were able to predict these fracture types. Also, the demonstration of FE and DVC as metrics of the strains in bones may be of substantial clinical value, informing treatment strategies and device selection and design. © 2017 Orthopaedic Research Society. Published by Wiley Periodicals, Inc. J Orthop Res 36:993-1001, 2018.
股骨颈骨折和转子间骨折，分别占所有股骨近端骨折的53%和43%。预测特定患者易发生的骨折类型，将有助于更精准地针对该患者进行药物和运动治疗、设计髋部保护器以及开展预防性手术，从而提高骨折预防策略的有效性。本研究假设骨折类型与患者特定的股骨结构密切相关，且可通过有限元（FE）方法进行预测。对14根股骨进行了双能X线吸收法（DXA）扫描、计算机断层扫描（CT）以及骨折力学测试。将有限元预测的骨折模式与实验观察到的骨折模式进行比较。采用数字体积相关（DVC）技术测量应变模式以解释股骨颈和转子间骨折模式，并与有限元预测的应变以及实验观察到的骨折模式进行比较。尽管加载方式相同，但股骨呈现出不同的骨折类型（6例股骨颈骨折和8例转子间骨折）。基于CT的有限元模型与实验观察结果匹配良好（86%），表明骨折类型可以被预测。DVC测量的应变和有限元预测的应变显示出明显的一致性。基于DXA的骨密度以及任何形态学特征，如颈直径、股骨颈长度或颈干角，均与骨折类型无关。总之，患者特定的股骨结构与骨折类型相关，有限元分析能够预测这些骨折类型。此外，有限元和DVC作为骨应变指标的证明可能具有重要的临床价值，可为治疗策略以及器械的选择和设计提供参考。© 2017年骨科学研究协会。由威利期刊公司出版。《矫形外科研究杂志》2018年第36卷，第993 - 1001页
