Direct printed absorbable metallic implants for bone reconstruction

Almost 20 percent of the current Western World’s population is over 65 years old, with a growing tendency. This demographic change and the demand for more mobility will result in increasing incidences of bone fractures due to age-related osteoporotic fragility leading to morbidity and expensive medical treatments. Treating large bone defects still remains a clinical challenge, mainly due to the lack of suitable bone implants. Additively manufactured absorbable porous metals may provide multiple prospects to meet the requirements for bone-mimetic implants. Firstly, multi-scale geometries of such implants can be customized to mimic the micro-architecture and mechanical properties of human bone. Secondly, their interconnected porous structure not only facilitates vascularization, but also increases the surface area to facilitate adhesion and proliferation of bone cells.

Finally, the absorption properties of such implants are adjustable.  This maintains the structural integrity of the implant throughout the bone healing process to ensure sufficient loadbearing if needed. After fracture healing, these implants will disintegrate within the body. Moreover, these properties make personalized bone-mimetic implants valuable for certain pediatric applications while reducing the risk of implant-associated infections.

Primary project leader Holger Jahr (Faculty 10, Institute of Anatomy and Cell Biology), and his Exploratory Research Space (ERS) project partners Mahtab Nourbakhsh (Faculty 10, Dept. of Geriatrics and Internal Medicine), Johannes Henrich Schleifenbaum (Faculty 4, Digital Additive Production), Kai-Uwe Schröder (Faculty 4, Structural Mechanics and Lightweight Design) highly appreciate the funding of the RWTH. Their 1-year-project aims at proofing that smart design principles from lightweight engineering can be realized using beyond-state-of-the-art direct metal printing technology to additively manufacture a novel type of loadbearing, fully biologically absorbable implants from improved biocompatible metal alloys.