Bioabsorbable metals hold a lot of potential as orthopaedic implant materials. Three metal families are currently being investigated: iron (Fe), magnesium (Mg) and zinc (Zn). Currently, however, biodegradation of such implants is poorly predictable. We thus used Direct Metal Printing to additively manufacture porous implants of a standardized bone-mimetic design and evaluated their mechanical properties and degradation behaviour, respectively, under Atomized powder was manufactured to porous implants of repetitive diamond unit cells, using a ProX DMP 320 (Layerwise, Belgium) or a custom-modified ReaLizer SLM50 metal printer. Degradation behaviour was characterized under static and dynamic conditions in a custom-built bioreactor system (37ºC, 5% CO2 and 20% O2) for up of 28 days. Implants were characterized by micro-CT before and after Micro-CT analyses confirmed average strut sizes (420 ± 4 μm), and porosity (64%), to be close to design values. After 28 days of In summary, DMP allows to accurately control interconnectivity and topology of implants from all three families and micro-structured design holds potential to optimize their degradation speed. This first systematic report sheds light into how design influences degradation behaviour under
Introduction. Glenoid loosening, still a main complication in shoulder arthroplasty, could be related to glenohumeral orientation and conformity, cementing techniques, fixation design and periprosthetic bone quality [1,2]. While past numerical analyses were conducted to understand the relative role of these factors, so far none used realistic representations of bone microstructure, which has an impact on structural bone properties [3]. This study aims at using refined microFE models including accurate cortical bone geometry and internal porosity, to evaluate the effects of fixation design, glenohumeral conformity, and bone quality on internal bone tissue and cement stresses under physiological and pathological loads. Methods. Four cadaveric scapulae were scanned at 82µm resolution with a high resolution peripheral quantitative computer tomography (XtremeCT Scanco). Images were processed and virtually implantated with two anatomical glenoid replacements (UHMWPE Keeled and Pegged designs, Exactech). These images were converted to microFE models consisting of nearly 43 million elements, with detailed geometries of compact and trabecular bone, implant, and a thin layer of penetrating cement through the