Objective gait analysis following total knee arthroplasty with a smart implant directs early intervention with manipulation under anesthesia

Abstract

Total knee arthroplasty (TKA) is a procedure increasingly in demand. While advancements in surgical techniques and implant designs have led to low complication rates and improved outcomes following TKA, patient satisfaction has not risen commensurately. Routine care may include clinical assessments, physical therapy notes, and patient reported outcome measures, each of which provides a discrete evaluation but may miss significant changes in daily activities. Here we present the case of a patient who underwent TKA with a tibial implant fitted with an embedded inertial measurement unit capable of providing extensive data on gait kinematics. Despite a successful, well-balanced knee replacement surgery and good clinical outcomes at 2 weeks, by 4.5 weeks post-surgery, she had increased self-reported pain scores and her walking speed, stride length and tibial range of motion (ROM) were declining compared to her TKA peers. The patient was called in to the office for evaluation, 3.5 weeks prior to her scheduled 8-week routine follow up. We proceeded with early manipulation under anesthesia, which lead to normalization of her knee ROM. In this case, gait data from the smart implant alerted us to a TKA patient who was failing to progress, prior to her routine follow-up visit. The daily remotely acquired kinematic data was instrumental in the early recognition and intervention. Availability of objective, trended, high-fidelity gait data from smart implants has the potential to identify clinical concerns early, improve efficiency in care, and increase patient and physician engagement in the recovery process.