Faculty of Biological Sciences, University of Leeds, UK.
Faculty of Biological Sciences, University of Leeds, UK.
Acta Biomater. 2018 Apr 15;71:339-350. doi: 10.1016/j.actbio.2018.02.030. Epub 2018 Mar 2.
Less than optimal particle isolation techniques have impeded analysis of orthopaedic wear debris in vivo. The purpose of this research was to develop and test an improved method for particle isolation from tissue. A volume of 0.018 mm of clinically relevant CoCrMo, Ti-6Al-4V or SiN particles was injected into rat stifle joints for seven days of in vivo exposure. Following sacrifice, particles were located within tissues using histology. The particles were recovered by enzymatic digestion of periarticular tissue with papain and proteinase K, followed by ultracentrifugation using a sodium polytungstate density gradient. Particles were recovered from all samples, observed using SEM and the particle composition was verified using EDX, which demonstrated that all isolated particles were free from contamination. Particle size, aspect ratio and circularity were measured using image analysis software. There were no significant changes to the measured parameters of CoCrMo or SiN particles before and after the recovery process (KS tests, p > 0.05). Titanium particles were too few before and after isolation to analyse statistically, though size and morphologies were similar. Overall the method demonstrated a significant improvement to current particle isolation methods from tissue in terms of sensitivity and efficacy at removal of protein, and has the potential to be used for the isolation of ultra-low wearing total joint replacement materials from periprosthetic tissues.
This research presents a novel method for the isolation of wear particles from tissue. Methodology outlined in this work would be a valuable resource for future researchers wishing to isolate particles from tissues, either as part of preclinical testing, or from explants from patients for diagnostic purposes. It is increasingly recognised that analysis of wear particles is critical to evaluating the safety of an orthopaedic device.
不理想的颗粒隔离技术阻碍了体内骨科磨损颗粒的分析。本研究的目的是开发和测试一种从组织中分离颗粒的改进方法。将 0.018mm3 的临床相关 CoCrMo、Ti-6Al-4V 或 SiN 颗粒注入大鼠膝关节 7 天进行体内暴露。处死动物后，使用组织学定位关节内的颗粒。用木瓜蛋白酶和蛋白酶 K 消化关节周围组织进行酶解，然后用钨酸钠密度梯度超速离心分离颗粒。从所有样本中回收颗粒，使用 SEM 观察，并使用 EDX 验证颗粒成分，结果表明所有分离的颗粒均无污染。使用图像分析软件测量颗粒的尺寸、长径比和圆度。回收前后 CoCrMo 或 SiN 颗粒的测量参数均无显著变化（KS 检验，p＞0.05）。钛颗粒在分离前后数量太少，无法进行统计学分析，但大小和形态相似。总的来说，该方法在从组织中分离颗粒的敏感性和效率方面，与目前的颗粒分离方法相比有了显著的改进，有望用于从假体周围组织中分离超低磨损的全关节置换材料的颗粒。
本研究提出了一种从组织中分离磨损颗粒的新方法。本工作中概述的方法将为未来希望从组织中分离颗粒的研究人员提供有价值的资源，无论是作为临床前测试的一部分，还是从患者的植入物中进行诊断目的。人们越来越认识到，分析磨损颗粒对于评估骨科器械的安全性至关重要。
