Instrumented hip joint replacements, femoral replacements and femoral fracture stabilizers

Abstract

This paper reviews instrumented hip joint replacements, instrumented femoral replacements and instrumented femoral fracture stabilizers. Examination of the evolution of such implants was carried out, including the detailed analysis of 16 architectures, designed by 8 research teams and implanted in 32 patients. Their power supply, measurement, communication, processing and actuation systems were reviewed, as were the tests carried out to evaluate their performance and safety. These instrumented implants were only designed to measure biomechanical and thermodynamic quantities in vivo, in order to use such data to conduct research projects and optimize rehabilitation processes. The most promising trend is to minimize aseptic loosening and/or infection following hip or femoral replacements or femoral stabilization procedures by using therapeutic actuators inside instrumented implants to apply controlled stimuli in the bone-implant interface.

Altering the Course of Technologies to Monitor Loosening States of Endoprosthetic Implants

“…Ledet et al [74] conducted an overview on sensor technology for instrumented orthopedic implants focused on physical parameters that do not provide an effective indication of the bone-implant integration state (characteristics, strength, stiffness, etc). Soares dos Santos et al [21,75] focused their analyses on all bioelectronic systems (actuation, monitoring, communication, and self-powering) incorporated into instrumented bone implants experimentally validated in vivo, which also confined the measurement technologies to force, moment, and temperature sensors. Karipott et al [76] also presented an enumeration of some technologies for biomechanical loading and biochemistry monitoring, but only three studies on implant failure detection were briefly reported.…”

“…Nevertheless, the uncemented fixation is more prone to induce bone loss due to stress shielding, a mechanical phenomenon resulting from different mechanical stimuli patterns delivered to the periprosthetic bone stock occurring after implant insertion [18,20]. Revision rates related to stress shielding-induced bone loss can exceed 50%, with incidences confirming implant loosening among the most common causes indicating bone replacement [1,21]. An accurate control of the factors modulating the bone-implant integration process is, then, mandatory to establish an asymptomatic and stable long-term fixation [20,[22][23][24][25].…”

“…However, future personalized medicine requires technology innovation to trigger the development of advanced implantable devices to simultaneously perform intensive monitoring and actuation operations, to avoid implant failures [18,29,30]. This new technological trend is emerging to implement multifunctional and intelligent orthopedic implants comprising feedback control systems with the ability to enhance bone growth when loosening states are detected [21,29]. The concept of instrumented implant is an unquestionably disruptive concept that aims to optimize the performance of implants [18,21,29,31].…”

“…This new technological trend is emerging to implement multifunctional and intelligent orthopedic implants comprising feedback control systems with the ability to enhance bone growth when loosening states are detected [21,29]. The concept of instrumented implant is an unquestionably disruptive concept that aims to optimize the performance of implants [18,21,29,31]. These are instrumented active technologies incorporating biophysical delivery systems, monitoring systems, wireless communication, and self-powering systems, such that their operation can be controlled by clinicians [18,21,[29][30][31].…”

“…The concept of instrumented implant is an unquestionably disruptive concept that aims to optimize the performance of implants [18,21,29,31]. These are instrumented active technologies incorporating biophysical delivery systems, monitoring systems, wireless communication, and self-powering systems, such that their operation can be controlled by clinicians [18,21,[29][30][31]. For example, this concept can be applied in hip prostheses by incorporating stimulation systems inside the implant (to deliver electromagnetic or mechanical stimuli, among others, to bone structures around the implants), near the proximomedial region where bone loss often occurs, as the stress distribution is usually reduced in this region following arthroplasty [18].…”