Orthopaedic surgeons Peter Sculco and Fred Cushner at New York’s Hospital for Special Surgery (HSS) have 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 cleared to collect data on an individual’s progress after a total knee replacement − information securely relayed to a cloud-based platform for the orthopaedic surgeon to review.

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

Remote monitoring can be especially useful during the early post-operative period, said Sculco.

“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,” he said. “The earlier you identify a patient who may not be progressing as well as you would like, the sooner you can intervene. 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 are then securely sent to a cloud-based platform where the orthopaedic surgeon can review them 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,” said 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 ten years.”

The smart knee will work with MyMobility, an app that enables patients to be actively engaged in their knee replacement journey from preparation to recovery.

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

HSS is an academic medical centre focused on musculoskeletal health. Founded in 1863, the hospital has the lowest complication and readmission rates in the USA for orthopaedics, and among the lowest infection rates.