Roth Klaus Edgar, Betz Simon, Schmidtmann Irene, Maier Gerrit Steffen, Ludwig Hans-Reiner, Vogl Thomas, Theisen Alf, Brochhausen Christoph, Götz Hermann, Drees Philipp, Rompe Jan Dirk, Kurth Andreas Alois
Centre of Orthopedic and Trauma Surgery, University Medical Centre of the Johannes Gutenberg University, Mainz, Germany.
University of Applied Sciences, Computer Science and Engineering, Frankfurt, Germany.
Knee. 2020 Jun;27(3):1078-1092. doi: 10.1016/j.knee.2020.03.012. Epub 2020 Apr 16.
The present study aimed to evaluate the functional, radiological and histological outcome of a customized focal implant for the treatment of focal full-thickness cartilage defects in sheep.
The study used magnetic resonance imaging data as the basis for construction of the titanium implant using a three-dimensional printing technique. This was then placed on the medial condyle of the knee joint in eight sheep and left in place in vivo over a period of six months. Following euthanasia, the local biological response was analyzed using micro-computed tomography, light microscopy and histological evaluation (International Cartilage Repair Society (ICRS) score). The variables were analyzed using a generalized linear mixed model. Odds ratios were given with 95% confidence intervals.
The osseointegration rate was 62.1% (SD 3.9%). All implants were prone to the neighboring cartilage bed (4.4-1096.1 μm). Using the IRCS score, the elements 'surface', 'matrix', 'cell distribution' and 'cell population' all showed pathological changes on the operated side, although these did not correlate with implant elevation. On average, a difference of 0.7 mm (±2 mm) was found between the digitally planned implant and the real implant.
As a result of imprecise segmentation and difficult preparation conditions at the prosthesis bed, as well as changes at the surface of the implant over the operational lifetime of the prosthesis, it must be stated that the approach implemented here of using a customized implant for the treatment of focal full-thickness cartilage defects at the knee did not meet our expectations.
本研究旨在评估定制的局部植入物治疗绵羊局部全层软骨缺损的功能、影像学和组织学结果。
本研究以磁共振成像数据为基础，采用三维打印技术制作钛植入物。然后将其植入8只绵羊的膝关节内侧髁，并在体内放置6个月。安乐死后，使用微型计算机断层扫描、光学显微镜和组织学评估（国际软骨修复协会（ICRS）评分）分析局部生物反应。使用广义线性混合模型分析变量。给出比值比及其95%置信区间。
骨整合率为62.1%（标准差3.9%）。所有植入物均倾向于邻近软骨床（4.4 - 1096.1μm）。使用ICRS评分，“表面”“基质”“细胞分布”和“细胞群体”等要素在手术侧均显示出病理变化，尽管这些变化与植入物抬高无关。数字化规划的植入物与实际植入物之间平均相差0.7mm（±2mm）。
由于假体床分割不精确、制备条件困难以及假体使用寿命期间植入物表面发生变化，必须指出，此处采用定制植入物治疗膝关节局部全层软骨缺损的方法未达到我们的预期。
