In-body Antenna Design for Next Generation Hip Implants

In this paper, an implant antenna to form a wireless link for a hip implant equipped with sensor technology to prevent mechanical overload is presented. The antenna is located in the ceramic head so that the integrity of the titanium femoral stem surface is protected and the antibacterial properties of the overall implant are maintained. The antenna is a conformal patch operating in the 2.4 GHz ISM band. The transmission coefficient between the implant antenna and an off-body antenna located 4 cm away from the human body surface is more than 65 dB where the implant depth is approximately 9 cm. −

I. Introduction

Total hip replacement is a remarkably successful treatment method for patients suffering from severe hip joint diseases such as osteoarthritis [1]. The average cost of a primary total hip replacement in Europe was €5043 in 2008 [2] while around 3.1 million replacement surgeries were conducted in 2018 [3]. Due to aging population, more operations are anticipated to increase over the next decades . For instance, the number of primary total hip replacement has been estimated to grow by 134% from 2012 to 2030 in England and Wales [4], 29% from 2016 to 2040 in Germany [5], and %25 from 2010 to 2030 in Sweden [6].