Alamanda Vignesh K, Demartino Ivan, Potter Hollis G, Koff Matthew F, Lin Bin, Muskat Ahava, Westrich Geoffrey H
Department of Orthopedic Surgery, Adult Reconstruction and Joint Replacement, Hospital for Special Surgery, New York, NY, USA.
Department of Radiology and Imaging, Hospital for Special Surgery, New York, NY, USA.
Arthroplast Today. 2020 Aug 26;6(4):694-698. doi: 10.1016/j.artd.2020.07.019. eCollection 2020 Dec.
The ability to utilize magnetic resonance imaging (MRI) to assess bony fixation in 3 dimensions may allow a better understanding of the implant design and bony integration. We hypothesized that a new 3-dimensionally printed cementless highly porous acetabular component (Stryker Trident II Tritanium) would show better fixation than an earlier cup from the same manufacturer as assessed by the noninvasive technique of multispectral MRI.
Multiacquisition variable-resonance image combination selective metal suppression MRI was performed in 19 patients implanted with a new 3-dimensionally printed cup and 20 patients who had received a previous-generation cup from the same manufacturer at 1-year follow-up. Each cup was graded globally as well as by 9 specific zones. Integration grades were performed for each zone: 0, full bone integration; 1, fibrous membrane present; 2, osteolysis; and 3, fluid present. A mixed-effects logistic regression model was used to compare fixation between the 2 groups.
All cups in both cohorts showed greater than 90% estimated global bony integration (3-dimensionally printed cups, 99.4%; regular cups 91.6%) with no osteolysis or fluid observed in any cup. The 3-dimensionally printed cup had 1 of 171 zones (0.6%) graded as fibrous membrane present, while the 2-dimensional group had 15 of 180 zones (8.3%) graded as fibrous. Of note, screw hole regions were omitted but may be read as fibrous membrane areas.
Using multiacquisition variable-resonance image combination selective MRI, our analysis showed greater osteointegration and less fibrous membrane formation in the 3-dimensionally printed cups than the control group at 1-year follow-up.
利用磁共振成像(MRI)在三维空间评估骨固定的能力,可能有助于更好地理解植入物设计和骨整合情况。我们推测,通过多光谱MRI这种非侵入性技术评估,一种新型三维打印的无水泥高孔隙率髋臼组件(史赛克Trident II Tritanium)的固定效果会优于同一制造商生产的早期髋臼杯。
对19例植入新型三维打印髋臼杯的患者和20例植入同一制造商前代髋臼杯的患者进行多采集可变共振图像组合选择性金属抑制MRI检查,随访1年。每个髋臼杯进行整体评分以及按9个特定区域评分。对每个区域进行整合分级:0级,完全骨整合;1级,存在纤维膜;2级,骨溶解;3级,存在液体。采用混合效应逻辑回归模型比较两组的固定情况。
两个队列中的所有髋臼杯估计整体骨整合均超过90%(三维打印髋臼杯为99.4%;常规髋臼杯为91.6%),且未观察到任何髋臼杯有骨溶解或液体。三维打印髋臼杯有171个区域中的1个(0.6%)被评为存在纤维膜,而二维组有180个区域中的15个(8.3%)被评为纤维性。值得注意的是,螺孔区域被排除在外,但可能被解读为纤维膜区域。
使用多采集可变共振图像组合选择性MRI,我们的分析显示,在随访1年时,三维打印髋臼杯比对照组具有更好的骨整合且纤维膜形成更少。