EAGER: Flexible wireless joint sensing system for knee arthroplasty

University Of North Texas, Denton TX

Investigators

Abstract

The objective of this research is to develop a low power flexible wireless joint sensor system using novel two dimensional (2D) nanomaterials. The sensor can be used for total knee arthroplasty which is a surgical procedure to replace the weight-bearing surfaces of the knee joint to relieve pain and disability. Approximately 20% of total knee arthroplasty may have soft tissue imbalance or mal-tracking components resulting in stiffness or subtle instability. Currently, surgeons generally relied solely on their best judgment in determining what felt like a balanced and stable knee. Therefore, ligament balancing during knee arthroplasty is a critical procedure necessary for the longevity of the prosthesis. The smart sensor system developed in this research can help orthopedic surgeons by providing real-time information about soft tissue adjustments and implant position during the surgical procedure. Since it is not a disposable sensor, it continues to provide real-time data to monitor the performance of the artificial knee even after the surgery. This enables surgeons to diagnose potential malfunction and adjust the alignment of the artificial knee during follow-up visits. The flexible wireless joint sensor system will be developed using smart materials such as graphene and MoS2, and power-efficient wireless sensing techniques. A new design of active sensor based on 2D materials will be fabricated and characterized. The flexible 2D sensor array will be connected to the programmable power unit for sweeping electric signal to measure the difference of conductivity of each unit with pressure change. It will detect joint pressure distribution signals with high sensitivity and rapid response with low power consumption. The measured pressure distribution signal will be transmitted to the control system wirelessly, and the results will be presented on a map at real-time. The circuitry for wireless sensor system will be optimized for low power, area consumption, and accuracy. The assembled sensor unit will be tested in situ by applying it in an artificial knee model. Biocompatibility of implants will also be evaluated systematically so that the materials meet the minimal biosafety criteria as bone implants. This research project will significantly enhance undergraduate and graduate education and research training in an integrative and interdisciplinary manner in the broader areas of materials, mechanical, biomedical, and electrical engineering. This interdisciplinary project will provide great educational and research opportunities to female students and students from underrepresented groups. This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.