Imagine knee replacement surgery with a “smart” implant that collects and transmits data enabling an orthopedic surgeon to monitor a patient’s recovery from afar. It became a reality this week when Peter Sculco, MD, and Fred Cushner, MD, orthopedic surgeons at Hospital for Special Surgery (HSS) performed the first knee replacement containing a smart sensor capable of measuring steps taken, walking speed, range of motion and other indicators of knee function following surgery.

An innovation in the growing field of remote patient monitoring, it is the first implantable device approved to collect data on an individual’s progress after a total knee replacement − vital information securely relayed to a cloud-based platform for the orthopedic surgeon to review. 

Known as the Persona IQ, the smart knee was granted authorization from the U.S. Food and Drug Administration (FDA) in August. Although the technology doesn’t preclude office visits altogether, it enables the doctor to actively monitor a patient’s recovery with real-world, objective data to supplement their care. 

Remote monitoring can be especially useful during the early post-operative period, Dr. Sculco says. “In the first several weeks following knee replacement, hard work is required from the patient, and there can be deviations in recovery that can set people on the wrong path. The earlier you identify a patient who may not be progressing as well as you would like, the sooner you can intervene,” he explains. “This could mean a change in an individual’s physical therapy plan, enhanced patient education, anti-inflammatory medication or the use of an ice machine. When I go into the exam room to see a patient at the six-week follow-up visit, I should have a very granular understanding of how his or her recovery is going.”

The smart knee contains a sensor that is integrated into the joint replacement prosthesis. Once implanted, it records and wirelessly transmits gait data and other information to a personal base station, about the size of a modem, that plugs into an outlet at the patient’s home. The data is then securely sent to a cloud-based platform where the orthopedic surgeon can review it and check on the patient’s progress and recovery.

“The smart knee uses the same material and technology found in implanted cardiac devices such as pacemakers,” explains Dr. Cushner, who is also a founder and chief medical officer of Canary Medical, the company that designed the sensor technology. “It collects data every day during the first year following surgery, providing objective, accurate information on how the knee is functioning. Patient monitoring can continue for much longer, though, as the battery that powers the device was made to last at least 10 years.”

Dr. Sculco notes that as time goes by and more patients receive the smart implant, it has the potential to amass a vast amount of information on gait metrics following knee replacement. Down the road, orthopedic researchers could potentially use data analytics and machine learning to translate that information into evidence-based recommendations to ultimately improve outcomes and enhance patient care.