Improving self-management of lower back pain with a core activity detecting belt

Lower back pain is one of the commonest ailments seen by the NHS, and a leading cause of sick leave and disability. The UK Government recommends that first line treatment should be exercise, which is often more effective, safer and cheaper, than painkillers or back surgery. However exercise is only effective if performed regularly and appropriately. This may explain why prescribing exercise for the back often does not work - because people tire of exercises, or perform manoeuvres incorrectly.

While physiotherapy can help with back exercises - by offering one-to-one personal training - this is a limited resource. Typically the NHS offers a small number of personalised exercise sessions, or a training class. But beyond this, back pain sufferers are merely provided with an exercise sheet, and expected to "get on with it" themselves.

This project will develop a simple device that can encourage people to perform back exercises by themselves. The device is a belt that detects activity of "core" muscles in the trunk; and then displays this activity back to the user via a smartphone or smartwatch. This enables users to "see" their muscles contract; track their exercise performance, and strive to reach daily workout goals. Not only can this incentivize - in the same way that step-counters motivate walking - but the belt will also indicate to people if they are performing exercises correctly or not.

The core muscles targeted are those that are worked on with back exercises. One set of muscles are the "Abs" (or "6-pack") that fitness fanatics know only too well; but others are a deeper thinner tummy muscle, and another one that runs down either side of the spine. When these other muscles are engaged with regular exercise, they can reduce or prevent back pain. However often people don't know how to engage them, even when they are shown by a physiotherapist. Hence the belt can show patients how to perform suitable exercises by enabling them to visualise the correct muscles that need to be contracted.

In our earlier research we showed that our belt device is a reliable way of measuring core muscles contracting, by comparison with a gold standard method, that is a sophisticated instrument called EMG, used only in laboratories. We also showed that when people used our device, in combination with a feedback App during back exercises, they increased the amount of effort and time they put into exercise, whether prompted or unprompted. We also found that subjects using the device with muscle feedback performed back exercises more appropriately, activating the right set of muscles. These effects were found in people with or without back pain.

Research participants felt more engaged and motivated to exercise when they used our invention; felt the belt was comfortable and the App easy to understand, and many wanted to use it again or purchase it.

Given encouraging results from our early studies, we now wish to develop the device further to ensure that the belt design is sufficiently comfortable, and simple to apply, for people to want to use it at home, repeatedly for weeks, months or even years. We also want the App to be easily understood, so it can be used without professional assistance. We shall test the belt and App out on people who have back pain, who have attended their GP or seen a therapist to help with this. Our device will supplement standard treatment. After 2 months of use, we shall see what effect the device has had on their level of exercise, and back pain.

We expect that patients with lower back pain will exercise more effectively and more often when provided with the muscle feedback belt, which is likely to reduce pain and disability. Given the expected cost of our device is low, and simple enough that anyone could put it on and use it, we expect our invention could be rolled out across the NHS, enabling effective self-care. This will reduce disability, dependency and reduce costs.

Lower back pain (LBP) is a leading cause of healthcare encounters and chronic disability. NICE guidelines recommend exercise as first-line treatment; but adherence is poor, limiting its effectiveness. Performance feedback with wearables enhances self-management, as proven by activity-trackers, which motivate walking and prevent cardiovascular disease. However equivalent personal devices for back exercises have not successfully translated into everyday practice. Trunk-worn motion sensors are insensitive to important core-stabilizing exercises, and are prone to inappropriate technique. Conversely, electromyography (EMG) biofeedback of core muscles - while proven to reduce LBP - is too expensive and unwieldly for routine use, necessitating professional supervision.

We developed and patented a wearable "smartbelt" sensor, that provides biofeedback of trunk muscle activity at significantly lower cost, and with more simplicity, than EMG. This enables the benefits of myographic biofeedback to be realized for widespread personal use, rather than limited to specialist centres.

Proof-of-concept experiments in 100 subjects, including those with LBP, show that the smartbelt:
1. detects contractions of 3 core muscles during back exercises with high accuracy;
2. discriminates muscle activity from environmental noises;
3. remains accurate across a wide weight range.
Additionally, smartbelt-based biofeedback:
4. increases core muscle engagement during back exercises;
5. improves quality of back exercises, by encouraging selective activation of trunk-stabilizing muscles;
6. increases quantity of self-initiated back exercises.

This project will:
1) advance smartbelt and biofeedback App development so as to enable independent home use, and optimize user-centred design;
2) determine appropriate exercises schedule, and biofeedback, to help people with LBP;
3) conduct a randomized clinical trial of smartbelt-based self-management for reducing LBP.