Lv Miko Lin, Ni Ming, Sun Wanju, Wong Duo Wai-Chi, Zhou Shuren, Jia Yongwei, Zhang Ming
School of Medical Instrument and Food Engineering, University of Shanghai for Science and Technology, Shanghai, China.
Department of Orthopedics, Pudong New Area People's Hospital Affiliated to Shanghai Jiaotong University, Shanghai, China.
Front Bioeng Biotechnol. 2022 Mar 9;10:791554. doi: 10.3389/fbioe.2022.791554. eCollection 2022.
The development of minimally invasive procedures and implant materials has improved the fixation strength of implants and is less traumatic in surgery. The purpose of this study was to propose a novel "double-point fixation" for calcaneal fractures and compare its biomechanical stability with the traditional "three-point fixation." A three-dimensional finite element foot model with a Sanders type IIIAB calcaneal fracture was developed based on clinical images comprising bones, plantar fascia, ligaments, and encapsulated soft tissue. Double-point and three-point fixation resembled the surgical procedure with a volar distal radius plate and calcaneal locking plate, respectively. The stress distribution, fracture displacement, and change of the Böhler angle and Gissane's angle were estimated by a walking simulation using the model, and the predictions between the double-point and three-point fixation were compared at heel-strike, midstance, and push-off instants. Double-point fixation demonstrated lower bone stress (103.3 199.4 MPa), but higher implant stress (1,084.0 577.9 MPa). The model displacement of double-point fixation was higher than that of three-point fixation (3.68 2.53 mm). The displacement of the posterior joint facet (0.127 0.150 mm) and the changes of the Böhler angle (0.9° 1.4°) and Gissane's angle (0.7° 0.9°) in double-point fixation were comparably lower. Double-point fixation by volar distal radius plates demonstrated sufficient and favorable fixation stability and a lower risk of postoperative stress fracture, which may potentially serve as a new fixation modality for the treatment of displaced intra-articular calcaneal fractures.
微创手术和植入材料的发展提高了植入物的固定强度，且手术创伤较小。本研究的目的是提出一种用于跟骨骨折的新型“双点固定”方法，并将其生物力学稳定性与传统的“三点固定”进行比较。基于包含骨骼、足底筋膜、韧带和包裹的软组织的临床图像，建立了一个具有Sanders IIIAB型跟骨骨折的三维有限元足部模型。双点固定和三点固定分别类似于使用掌侧桡骨远端钢板和跟骨锁定钢板的手术过程。通过使用该模型的步行模拟来估计应力分布、骨折位移以及Böhler角和Gissane角的变化，并在足跟触地、单脚支撑和蹬离瞬间比较双点固定和三点固定之间的预测结果。双点固定显示出较低的骨应力（103.3±199.4MPa），但植入物应力较高（1084.0±577.9MPa）。双点固定的模型位移高于三点固定（3.68±2.53mm）。双点固定时后关节面的位移（0.127±0.150mm）以及Böhler角（0.9°±1.4°）和Gissane角（0.7°±0.9°）的变化相对较低。掌侧桡骨远端钢板的双点固定显示出足够且良好的固定稳定性以及较低的术后应力性骨折风险，这可能潜在地成为治疗移位关节内跟骨骨折的一种新的固定方式。
