3D打印技术在关节外科的应用

Application of 3D printing technology in joint surgery

3D打印技术问世于1984年,属于增材制造（additive manufacturing,AM）的一种。AM是相对于传统机械制造而言的,传统的制造过程是一个＂减材＂的过程,先是通过模铸、精煅等获得产品大致原型,再进行精加工,从而得到最终产品。

3D printing technology is based on advanced 3D design,computer-aided design,principles of discrete/stacked molding,manufacturing technology,numerical control technology,three-dimensional CT technology,rapid prototyping technology.The collected data are three-dimensionally modeled and printed which approximate the anatomical structure of real tissues and organs.Its application in joint replacement strongly promotes the development.At present,it includes but is not limited to the following aspects：preoperative planning,medical teaching,communications between doctors and patients,reduction of learning curve,individualized prosthesis,production of personalized templates,mass production of 3D printed prostheses,bioactive joint replacement,etc.Its application is not difficult,however,there are still some limitations.The cost of the 3D printing physical model is high.Due to the stiffness and other biomechanical indicators,there are no 3D printed femoral prostheses.In the case of biological stent material printing,there are still some problems need to be solved on how to deal with simultaneous printing of composite materials and complex pore structure.The recycling of the 3D printing raw material powder may change the mechanical properties of the implant.The most crucial point is that its extra effects and cost-effectiveness have not been proved.Therefore,most current total knee replacements still rely on conventional tools.In order to deal with morphologically-extensive bone defects during revision surgery,existing prosthesis has been able to handle most of these conditions,so that there is no large demand on the customized prosthesis.In addition,the clinical application of artificial-value prosthesis is also limited by different regulations.It is believed that with the development of 3D printing technology and the popularization of its clinical applications,related issues will be gradually solved.It will provide impetus for the development of joint surgery.