Biodegradable Iron for Orthopaedic Scaffold Applications

Millions of procedures are carried out annually across the world in order to repair bone defects. As a result of enhanced life expectancy, the amount of procedures and healthcare expenditure, are set to continue increasing, and so researchers are in a constant search for more effective and efficient solutions for bone repair.

When treating substantially large defects, surgeons make use of implants known as scaffolds; bone support structures that mimic the spongy component of bone. Traditionally, scaffolds may be either permanent or biodegradable. Permanent scaffolds either remain within the bone, leading to bone weakening, or are removed following a revision surgery.

On the other hand, existing biodegradable scaffolds also have their limitations. Biodegradable polymeric scaffolds are generally too weak for load-bearing applications while ceramic scaffolds tend to be too brittle for shock-loading. Magnesium has long been studied as a biodegradable metal, yet its fast corrosion rate has prevented its use clinically. Iron and iron alloys have recently gained attention for this application, however their slow degradation rate could lead to similar problems encountered with permanent implants. Further research effort is required for the potential of Fe-based implants to be exploited.

BioSA is financed by the Malta Council for Science and Technology, for and on behalf of the Foundation for Science and Technology, through the FUSION: R&I Technology Development Programme (BioSA R&I-2017-037). The project aims to address the limitations of existing bone scaffold solutions through the development of an implant with a specific iron-based composition and an innovative manufacturing route.

The final product is aimed to be both bioresorbable and patient-specific while also being relatively inexpensive to produce. The mechanical, corrosion, cytotoxicity and small animal testing required to develop such an implant, will be carried out by the interdisciplinary team that includes members from various departments from the University of Malta, as well as the Orthopaedics department from the national hospital, Mater Dei. The synergistic combination of expertise in fields like materials engineering, corrosion science, additive manufacturing, microbiology, toxicology, animal testing and orthopaedic surgery, will eventually lead to a technical ready high value-added product which can be licensed out to a global biomedical company; the final stage of the project.