Transformation Directorate

Rehabilitation after knee replacement surgery using remote monitoring and wearable technology

Knee replacement surgery is on the rise and traditionally patients can stay in hospital for up to 5 days. The pathway had not changed for years.

This pilot study observed how remote monitoring could impact rehabilitation after knee replacement surgery. Technology used included:

  • a wearable sensor
  • a smartphone app
  • a web dashboard

This formed part of a wider digital day-case knee replacement pathway.


Recovery after joint replacement consists of face-to-face appointments with therapists and self-managed rehabilitation.

The care team wanted to use wearable technology to reduce face-to-face appointments. This was particularly important as patients recover from COVID-19.

The team also wanted to show how wearable technology could:

  • improve patient satisfaction after joint replacement surgery
  • ensure more patients followed exercise routines
  • improve patient outcomes
  • reduce the length of stay in hospital


The challenge was to innovate the whole pathway with digital technology. This would:

  • prepare patients for surgery and recovery
  • reduce touch-time and recovery time in theatre and on the ward
  • promote self-care and management
  • minimise the number of face-to-face interactions between healthcare professionals and patients

Solution and impact

BPMpathway is a wearable sensor accompanied by a smartphone app and dashboard software which patients and clinicians can use.

The pilot demonstrated that wearable technology reduced face-to-face physio time. It also allowed physiotherapists to focus on patients who needed the support. All this significantly reduced costs and improved outcomes.


The sensor is equipped with a gyroscope and accelerometer. It’s worn on the lower leg and monitors the patient’s range of motion (ROM). This data is then automatically and wirelessly uploaded for patients and clinicians to review on their app or dashboard.


  • Patients work through daily exercises using the wearable sensor and the BPMpathway app.
  • Patients can progress through the exercises at their own pace for better self-management.
  • Patients can log information about pain and discomfort.
  • Physiotherapists can access the BPMpathway dashboard to see exercise progression, so multiple home visits are not needed.
  • Patients who are not exercising properly or enough are called and home visits are arranged if needed.
  • Patients can message the therapy team if they have any questions or concerns.


  • Wearing the sensor, patients can rehabilitate in an environment they’re comfortable with.
  • The patient having access to rehabilitation at home reduces travel and their carbon footprint.

Key learning points

  • Ensure the whole team is aware of the technology, how it works and how to address minor technical difficulties the patient may experience. All clinicians who see patients should be trained on how to use the device.
  • Ensure everyone has access to the technical support phone number to avoid any delays in fixing technical difficulties.
  • Service champions can help train other team members.
  • Patient training should be absorbed into pre-assessment, which is key in using the device successfully. Pre-assessment becomes a ‘one stop shop’ where occupational therapists, physiotherapists, nurses and the anaesthetist come together to streamline the pathway.
  • Allocate the physiotherapist 15 minutes each morning to check on patients who are using the device and time to support patients if needed. This extra time will soon cancel out costs as time is saved in other areas.
  • Health and digital inequalities must be considered, and this pathway is not suitable for all patients. Traditional rehabilitation pathways need to be kept open for patients who might not be able to use the wearable device or access the app.

Key figures

  • In total 23 patients took part and of those 21 were suitable for the pilot analysis.
  • The sensor was worn on 52% of available days, with participants using it for 31 days on average.
  • 34% of patients used the wearable device every day before their operation.
  • 62% of patients wore the sensor every day after their operation.
  • 19% of patients wore the sensor every day of their recovery after an operation.
  • Patient’s range of movement (ROM) after the operation was on average 55 degrees of flexion of the knee on day 1. This increased to an average of 136 degrees at 7 weeks after surgery.
  • If the patient wore the sensor, there was a positive correlation in the improvement in ROM from initial surgery to the final readings.
  • Total physiotherapy visits reduced from 6 to an average of 4.
  • The remote sensor saved the service £1,450 across the pilot.
  • Overall, the extra £100 to £200 per patient (for the sensor) will help to save money in other areas of the service, for example therapy costs.
  • Preparing patients better for surgery has the potential to reduce bed days. This saves the Trust money, with a day's stay following total knee replacement costing £1,750.
  • There are no extra requirements of IT, once the initial information governance is established, and the extra time due to monitor the dashboard will be quickly absorbed by time savings elsewhere.

Patient feedback

“The sensor kept me motivated each day to do my exercises. Having the sensor made me do my exercises daily because I knew the physios were watching me. I didn’t feel as though I was on my own.”

Jaqueline, patient

"It [the range of motion sensor] aided my ROM exercises and encouraged my performance.

Thanks to the BPM pathway, I was discharged early. At 3 weeks post-surgery I was able to be back out on the field coaching rugby. I didn’t expect to go home on the same day… For my recovery, it was good. The constant dialogue [through] BPM about the way I was using the sensor and the daily communications with the physios about how I was doing, what I needed to do, was way above expectations.”

Nick, patient

“Using the app itself was brilliant, it gave me a guideline of what I should be doing each day.”

Linda, patient

Find out more

Digital day case knee replacement with BPMpathway YouTube video

A patient's (Linda) experience of digital day-case knee replacement YouTube video

Patient stories: leading your own recovery case studies on the B Braun website

Key contacts

Mr Graham Walsh, Consultant Orthopaedic Surgeon, Associate Medical Director and Chief Clinical Informatics Officer, Calderdale and Huddersfield NHS Foundation Trust

Lynsey Cumberland, BPM National Product Specialist, B Braun Medical Ltd