A physio in your pocket

By Navraj S Nagra and Maxime Cox

Knee replacement is regarded as one of the most sucessful medical interventions (1); over a hundred-thousand knee replacements were performed across the UK last year (2). This number is ever-increasing in the context of an ageing population (2). Whilst knee replacement is undoubtedly effective, a key and often variably implemented part of rehabilitation is the subsequent physiotherapy (3).

Current physiotherapy provision has several problems. Firstly, it is expensive (4). Secondly, there is a shortage of physiotherapists in the NHS. Models have shown that an extra 500 physiotherapists need to join the workforce each year just to keep track with demand (5). As a result, patients will only see a physiotherapist once or twice after a knee replacement. Thirdly, a significant proportion of patients have poor compliance to physio (6).

Limited availability, compounded by poor patient compliance, results in patient complications such as reduced range of motion within their artificial knee joint, persistent pain, and muscle weakness longer term (3). These problems contribute to the 30% of patients who report dissatisfaction with their knee replacements – consuming further NHS resources in their subsequent management (7).

Therefore, the NHS stands to gain from solutions which will improve outcomes following knee replacement.

Recently we have noticed a rising trend for the use of technology in the realm of enhanced recovery after surgery, particularly in orthopaedics. For example, specific to knee replacements – Darzi et al. have investigated the use of wearable sensors for early identification of patients who are developing complications after surgery (8), whilst Negus et al. have looked at using the proprioceptive technology within the Nintendo Wii games console for home-based rehabilitation with a focus on balance and proprioception (9).

But what about patients who do not have a games console in their living room? And is there a more cost-effective way to monitor and help patients rather than using expensive wearable sensors that are easily mislaid?

With powerful smartphones being ubiquitous in modern society, our question is whether we can solve the physiotherapy shortage and poor patient compliance with mobile health (mHealth) solutions. Through mHealth, it is possible to turn a patient’s mobile phone into their own personal physiotherapist. Some companies already offer physiotherapy solutions, showing example videos via mobile platforms, such as BlueJay PT, PhysioTools and Physiotec, amongst others. However, the efficacy of existing platforms has not been evaluated through a published trial at the time of writing.

We decided to see if we could create an evidence-based solution  developed with the patient in mind.  To do this our Oxford-based team created a ‘digital physiotherapist’,  which can be installed on a patient’s mobile phone device as an app called enRecover (enhancedRecovery),  that is free for patients to use via the NHS. We are working in conjunction with the Oxford Academic Health Science Network (AHSN) to build, test and implement this app as part of a system that benefits patients, clinicians and commissioners alike.

Research has also shown that patients who are actively monitored, given regular motivation, in addition to illustrative materials – will have better compliance and adherence with physiotherapy and improved health outcomes (6). Our mHealth device sends patients personalised push notification reminders for when they need to perform exercises. The material contains high-quality videos, which remind patients how to perform these exercises. The app also includes patient-specific advice for post-operative care after knee replacement. Data from the app can be fed back to clinicians who will monitor patient progress remotely. Later this year we will be running a randomised controlled trial to determine its efficacy compared with standard physiotherapy care after knee replacement.

At enRecover, we firmly believe mHealth physiotherapy solutions will improve outcomes for patients, create substantial savings to the NHS, and undoubtedly play a key role in the future of post-operative patient care.

The team can be contacted at hello@enRecover.co.uk

Conflicts of Interest. Authors Dr Navraj S Nagra and Maxime Cox are academics at the University of Oxford who are developing enRecover, an mHealth app offering post-operative physiotherapy support. enRecover will be running its first randomised controlled trial in 2018.

Dr Navraj S Nagra is Clinical Research Fellow at Oxford University Hospitals NHS Foundation Trust, a DPhil Candidate at the University of Oxford and Founder and CEO of enRecover Healthcare. He believes in using digital disruption to improve health equality and provision for patients.



Maxime Cox has a background in health consulting and is reading Medicine at the University of Oxford. As the Head of Technology and Innovation at enRecover Healthcare, he is leading product development to provide optimal value for the health economy and improve patient outcomes.



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