Radiofrequency induced heating of biodegradable orthopaedic screw implants during magnetic resonance imaging

• Published in: Bioactive materials 2023-07, Vol.25, p.86-94
• Main Authors: Espiritu, Jonathan, Berangi, Mostafa, Cwieka, Hanna, Iskhakova, Kamila, Kuehne, Andre, Florian Wieland, D.C., Zeller-Plumhoff, Berit, Niendorf, Thoralf, Willumeit-Römer, Regine, Seitz, Jan-Marten
• Format: Article
• Language: English
• Subjects: Biodegradable implants; Magnesium; Magnetic resonance imaging; Medical imaging; Patient safety
• ISSN: 2452-199X; 2452-199X
• DOI: 10.1016/j.bioactmat.2023.01.017

Magnesium (Mg)-based implants have re-emerged in orthopaedic surgery as an alternative to permanent implants. Literature reveals little information on how the degradation of biodegradable implants may introduce safety implications for patient follow-up using medical imaging. Magnetic resonance imaging (MRI) benefits post-surgery monitoring of bone healing and implantation sites. Previous studies demonstrated radiofrequency (RF) heating of permanent implants caused by electromagnetic fields used in MRI. Our investigation is the first to report the effect of the degradation layer on RF-induced heating of biodegradable orthopaedic implants. WE43 orthopaedic compression screws underwent in vitro degradation. Imaging techniques were applied to assess the corrosion process and the material composition of the degraded screws. Temperature measurements were performed to quantify implant heating with respect to the degradation layer. For comparison, a commercial titanium implant screw was used. Strongest RF induced heating was observed for non-degraded WE43 screw samples. Implant heating had shown to decrease with the formation of the degradation layer. No statistical differences were observed for heating of the non-degraded WE43 material and the titanium equivalent. The highest risk of implant RF heating is most pronounced for Mg-based screws prior to degradation. Amendment to industry standards for MRI safety assessment is warranted to include biodegradable materials. [Display omitted] •The formation of degradation layer influences RF Mg-based implant heating.•There are no statistical differences in RF heating caused by Mg implants and Ti.•The highest risk of RF heating may occur after initial implantation.