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Orthopaedic implants, such as intervertebral disc endoprostheses (IDEs) are difficult to manufacture by means of conventional methods because of their complex shape. However, technologies developed in recent years, such as selective laser melting, could simplify this process. Although this method is attractive in both manufacturing and rapid prototyping of IDEs, little is known about their tribological performance. The functional aim of the work is to conduct a tribological evaluation of the ASTM F75 alloy after selective laser melting process and to investigate the viability of the technology in IDE design. The research aim was an explanation of the wear mechanism of bearing surfaces with respect to the reference material.

In this paper, the tribological test results of a lumbar IDE prototype fabricated by selective laser melting and forging is presented and compared. The endoprostheses were fabricated from commercially available ASTM F75 powder using a selective laser melting device. As a reference material, a forged ASTM F1537 LC alloy was used. Comparative wear and friction tests were carried out with the use of a unique spine simulator.

The obtained results confirm the viability of the selective laser technology in endoprosthesis design. Unfortunately, poorer tribological wear resistance of endoprostheses produced by means of selective laser melting (SLM) technology compared with that of the reference material calls into question the possibility of using these technologies in the manufacturing process of endoprosthesis' components exposed to tribological wear.

This paper presents the friction and wear behaviour of the lumbar IDE prototype. The tests were carried out in motion and loading conditions close to those we observe in the lumbar spine.

The purpose of this paper is to present the methodology of a design process of new lumbar intervertebral disc implants with specific emphasis on the use of rapid prototyping technologies. The verification of functionality of artificial intervertebral discs is also given. The paper describes the attempt and preliminary research to evaluate the properties of the intervertebral disc implant prototypes manufactured with the use of different rapid prototyping technologies, i.e. FDM – fused deposition modelling, 3DP – 3D printing and SLM – selective laser melting.

Based on the computed tomography (CT) scan data, the anatomical parameters of lumbar spine bone tissue were achieved, which were the bases for the design-manufacture process carried out with the use of computer-aided designing/computer-aided engineering/computer-aided manufacturing systems. In the intervertebral disc implant design process, three RP technologies: FDM, 3DP and SLM were used for solving problems related to the reconstruction of geometry and functionality of the disc. Some preliminary tests such as measurement of roughness and structural analyses of material of prototypes made by different prototyping technologies were performed.

This paper allowed the authors to elaborate and patent two new intervertebral disc implants. Because the implant designs are parametrical ones with relation to lumbar bone tissue properties measured on CT scans, they can be also made for individual patients. We also compared some of the properties of intervertebral implants prototypes made with the use of FDM, 3DP and SLM technologies.

The paper presents the new intervertebral disc implants and their manufacturing by rapid prototyping. The methodology of designing intervertebral disc implant is shown. Some features of the methodology make it useful for preoperative planning of intervertebral disc surgery, as well.