Recent innovations in sensor technologies demonstrated huge potential in orthopedic surgery, evolving beyond the bulky, expensive and less reliable technologies of the past.
The idea behind this new generation of wireless, smart implants is to provide personalized data that can be used to optimize outcomes for patients.
Implantable sensors can be used for measuring parameters such as force, torque and pressure. Smart implants such as Zimmer Biomet's Persona IQ are being developed to enable better remote monitoring, tracking steps, range of motion and other metrics for patients and physicians.
Persona IQ has a smart sensor that can count steps and measure walking speed, range of motion and other indicators of knee function after surgery, according to Zimmer Biomet. It wirelessly transmits data and works with the company's Mymobility app for patients.
Orthopedic surgeons Peter Sculco, MD, and Fred Cushner, MD, of New York City-based Hospital for Special Surgery, performed the first knee replacement with the implant in October.
"It collects data every day during the first year following surgery, providing objective, accurate information on how the knee is functioning," Dr. Cushner said in a news release. "Patient monitoring can continue for much longer, though, as the battery that powers the device was made to last at least 10 years."
As more patients receive the smart implant, it has the potential to gather a vast amount of data on gait metrics following knee replacement. In the future, orthopedic researchers may be able to use data analytics and machine learning to translate that information into evidence-based recommendations to improve patient care and outcomes.
Stryker is focused on developing its own portfolio of smart implants and wearables. Last year, it acquired OrthoSensor, a digital technology company focused on total joint replacements.
"Patient recovery will become more active as real-time measurement on key performance insights drive improved outcomes and patient satisfaction," according to Spencer Stiles, Stryker's group president of orthopedics and spine.
Stryker said the acquisition complements its Mako SmartRobotics technology by advancing robotic workflow through a single data-driven feedback mechanism. OrthoSensor's MotionSense remote patient-monitoring wearables and mobile application will also combine with OrthloLogIQ — Stryker's cloud-based data platform — to grow its data analytics capabilities.
"The impetus for Stryker acquiring OrthoSensor was to utilize sensors to better understand patients through their arthroplasty journey utilizing objective data," said Martin Roche, MD, founder of OrthoSensor and director of hip and knee arthroplasty at HSS Florida in West Palm Beach.
"When we plan robotic surgery, we will have some information preoperatively through wearables, and now with sensor-assisted robotic surgery, we have real-time data related to alignment, navigated gap distances and the true ligament tension through full motion," he said. "This data will enable the robot to perform a more accurate surgical procedure to hit your target zone of personalized knee balance."
As Stryker brands its Mako robot to the knee, the hip and into the shoulder with its $4 billion acquisition of Wright Medical and in the future into spine, the company wants to integrate sensors into all platforms, according to Dr. Roche.
"That means every implant they put in will have intelligence embedded in it, so we can really understand a patient's function, kinematics and potentially monitor for infection, healing, etc.," he said.
Ultimately, implantable sensors hold great promise for joint replacements and spinal fusion as the ability to monitor load sharing between implant and bone will allow clinicians to identify problems early in their development.