Off-the-shelf 3D printed titanium cups in primary total hip arthroplasty

Abstract

Three-dimensional (3D)-printed titanium cups used in primary total hip arthroplasty (THA) were developed to combine the benefits of a low elastic modulus with a highly porous surface. The aim was to improve local vascularization and bony ingrowth, and at the same time to reduce periprosthetic stress shielding. Additive manufacturing, starting with a titanium alloy powder, allows serial production of devices with large interconnected pores (trabecular titanium), overcoming the drawbacks of tantalum and conventional manufacturing techniques. To date, 3D-printed cups have achieved dependable clinical and radiological outcomes with results not inferior to conventional sockets and with good rates of osseointegration. No mechanical failures and no abnormal ion release and biocompatibility warnings have been reported. In this review, we focused on the manufacturing technique, cup features, clinical outcomes, open questions and future developments of off-the-shelf 3D-printed titanium shells in THA.

Keywords: Socket; Highly porous; Additive manufacturing; Ultraporous; Trabecular; Beam melting

Core Tip: Three-dimensional printed titanium cups theoretically provide a porous, rough surface that improves local vascularization and osseointegration, while avoiding stress shielding because of the low elastic modulus. We herein discuss the manufacturing, main features, and clinical results obtained with 3D-printed titanium cups, with a focus on the open questions and possible future developments to improve this newborn device and technology.