Total knee arthroplasty requires effective rehabilitation to achieve optimal results, but institutions often rely on unsupervised home exercises due to cost constraints. Wearable sensors have become increasingly popular as a potential method of monitoring patients remotely to ensure efficacy and compliance.
Wearable sensors also offer bespoke rehabilitation for patients based on their individual expectations and goals. They provide a means for two-way communication between the clinical team and the patient and can allow for objective data on pain and function to be captured. This empowers patients to take control of their rehabilitation.
Trials have been conducted using wearable sensors which can be classified as either knee sensors which are inertial measurement units to specifically monitor the knee joint or general physical activity sensors such as commercially available pedometers. Technological interventions allow home-based telerehabilitation. This may provide the supervision needed for greater compliance and effectiveness, while also significantly reducing health resource use associated with face-to-face rehabilitation.
A systematic review of the literature from 1st January 2000 to 17th February 2022 was undertaken by Samuel W. King et al. The study has been published in ‘Indian Journal of Orthopaedics.’ Devices were categorized as joint-specific or physical activity sensors. Studies were classified as those providing remotely supervised rehabilitation as an additional or as an alternative intervention.
Key findings of the study were:
• Remotely supervised rehabilitation using wearable sensors demonstrated similar outcomes when provided as an alternative to standard care in most studies.
• One group found improved outcomes for knee-specific sensors compared with standard care.
• There were improved physical activity and healthcare resource use outcomes described in the literature where sensors were used in addition to standard care.
• This review found evidence for the use of wearable sensors in remotely supervised rehabilitation following knee arthroplasty surgery. This included methodological heterogeneity, differing definitions of standard care, and variable follow up periods. Robust randomized control trial data with a longer follow-up period are needed.
The authors concluded that – “The use of remotely monitored rehabilitation with wearable sensors has the potential to provide the advantages of supervised rehabilitation with respect to compliance and assessment of complications. It may also reduce the costs of post-operative rehabilitation following arthroplasty surgery, which is known to be highly variable between individuals, institutions and healthcare systems. Continuous data collection enables monitoring of temporal changes in a more meaningful way rather than simply using snapshot data when a patient visits the clinic at a certain time point. The use of Artificial Intelligence to diagnose and predict patients with poor or suboptimal outcomes will help reduce the further burden on healthcare, improve patient satisfaction and ensure timely rehabilitation in patients undergoing a total knee replacement.”

Further reading:
“Wearable Sensors to Guide Remote Rehabilitation Following Knee Arthroplasty Surgery”
Samuel W. King, Momin Eltayeb et al
Indian Journal of Orthopaedics (2023) 57:624–634
https://doi.org/10.1007/s43465-022-00785-3