Custom design and biomechanical analysis of 3D-printed PEEK rib prostheses

A tumour resection normally involves a large tissue resection and bone replacement. Polyether ether ketone (PEEK) has become a suitable candidate for use in various prostheses owing to its lightness in weight, modulus close to that of natural bone, and good biocompatibility, among other factors. This study proposes a new design method for a rib prosthesis using the centroid trajectory of the natural replaced rib, where the strength can be adjusted by monitoring the cross-sectional area, shape, and properties. A custom-designed rib prosthesis was manufactured using fused deposition modelling (FDM) manufacturing technology, and the mechanical behaviour was found to be close to that of a natural rib. A finite element analysis of the designed rib was carried out under similar loading conditions to those used in mechanical testing. The results indicate that the centroid trajectory derived from a natural rib diaphysis can provide reliable guidance for the design of a rib prosthesis. Such methodology not only offers considerable design freedom in terms of shape and required strength, but also benefits the quality of the surface finishing for samples manufactured using the FDM technique. FDM-printed PEEK rib prostheses have been successfully implanted, and good clinical performances have been achieved.