Multiscale Sensing of Bone-Implant Loosening for Multifunctional Smart Bone Implants: Using Capacitive Technologies...

Area of Science:

• Biomedical Engineering
• Materials Science
• Medical Devices

Background:

• Rising life expectancy increases non-communicable diseases like osteoarthritis, leading to more joint replacement surgeries.
• Approximately 10% of joint replacement surgeries require revision due to issues with bone-implant fixation.
• Current monitoring methods lack sensing capabilities for the bone-implant interface, hindering early detection of loosening.

Purpose of the Study:

• To evaluate cosurface capacitor networks for monitoring bone loosening in peri-implant regions at various frequencies.
• To assess the effectiveness of capacitive sensing with hydroxyapatite-based layers.
• To demonstrate the control of capacitive networks using extracorporeal informatic systems for smart implants.

Main Methods:

• In vitro testing of a web-based sensor network with striped and interdigitated capacitive sensors.
• Investigation of cosurface capacitor networks with and without hydroxyapatite-based layers.
• Implementation of a Raspberry Pi-hosted web server for data communication.

Main Results:

• Cosurface capacitor networks effectively monitored bone loosening across extended regions and frequencies.
• Hydroxyapatite-based layers had a minimal impact on determining fixation states.
• Extracorporeal informatic systems successfully enabled continuous monitoring via the sensor network.

Conclusions:

• Cosurface capacitive sensing offers a promising method for monitoring bone-implant fixation.
• Extracorporeal informatic systems facilitate continuous patient monitoring with smart implants.
• This technology advances the development of multifunctional implants, aiming to reduce revision surgery rates.