Device enables people with arm disabilities following a stroke to do more physical training

A rehabilitation device can increase how often and how regularly stroke patients do arm exercises to aid their recovery, without the need for supervision in hospital by a therapist. The new study looked at the GripAble™ device, created by researchers at Imperial College London and clinicians at Imperial College Healthcare NHS Trust, which consists of a lightweight electronic handgrip that interacts wirelessly with a standard PC tablet to enable the user to play arm-training games, called ‘exergaming’.

The study has been funded by the NIHR Imperial Biomedical Research Centre (BRC) and is published in Neurorehabilitation & Neural Repair.

To use it, patients squeeze, turn, or lift the handgrip, and it vibrates in response to their performance whilst playing. The device uses a novel mechanism, which can detect the tiny flicker movements of severely paralysed patients and channel them into controlling a computer game.

Over five million people in the UK live with arm weakness, with stroke damage accounting for one million of those people. Around 60 per cent of stroke survivors experience persistent arm weakness. The only intervention shown to improve arm function is repetitive, task-specific exercise but this generally requires one to one support from an occupational therapist or physiotherapist.

In a clinical trial of 30 patients at Charing Cross Hospital, researchers from Imperial College Healthcare NHS Trust, Imperial College London and the University of Southampton found that the device enabled patients to do, on average, 104 arm repetitions per day whereas with conventional therapy the average was 15. They also found patients used the device for 26 minutes a day on average, which was in addition to 25 minutes daily conventional therapy. This doubling of the total exercise duration is significantly greater than standard care.

Michelle Broderick, lead author of the study and clinical research therapist in stroke at Imperial College Healthcare NHS Trust, said: “Stroke is a major cause of arm weakness in the UK and can significantly impact survivors’ lives, making it hard for them to do routine daily tasks and limiting independence. Previous studies have shown that repetitive exercise is vital for improving arm weakness, but this requires one to one support from a therapist. Stroke survivors also face challenges during their recovery which can limit their ability to initiate or engage in independent exercise or rehabilitation activities.

“This study is the first to show that a rehabilitation device – GripAble – can achieve significant increases in the amount of exercise patients do compared to supervised therapy. This work helps us understand whether using the device would be feasible and realistic for patients recovering from a stroke so that we can go on to further study the benefit of using the device in a wider group of patients over a longer period of time.

“It’s great to see that patients were able to use the device independently and our findings suggest that a significant proportion of stroke survivors may potentially benefit from exergaming alongside conventional therapy. This could improve patient outcomes as well as easing pressure for the NHS in terms of infrastructure and resources.”

Dr Paul Bentley, co-author of the study and clinical director of the Imperial College Network of Excellence in Rehabilitation Technology at Imperial College London, added: “The findings from this clinical trial provide evidence that GripAble can be adopted to help further support stroke patients with severe arm weakness with their rehabilitation unsupervised.

“This could have big implications for the NHS, given that recovery from stroke is strongly influenced by exercise intensity. Our technology can be used by patients to continue with their physiotherapy outside of standard treatment and help with their recovery. The long-term aim of GripAble is that patients can use it outside of a clinical setting such as in their homes and communities and we are now working to further assess the device’s impact on clinical outcomes.”

In recent years, a growing number of rehabilitation technologies have emerged that boost the potential to provide cost-effective, intensive exercise for the upper limbs. However, studies of these technologies have typically focused on high-functioning patients, which limits the applicability of their findings.

For this study, patients with arm weakness following a stroke were recruited between September and December 2019, given a GripAble device and taught to use it in a single training session. The participants were then left to use the device without any supervision over eight days. The researchers compared the number of exercise repetitions patients did as a result of the device with conventional therapy at the hospital. 26 of the 30 patients were able to use the device meaningfully with their affected limb.

The researchers also surveyed the participants and found that 57 per cent found the device easy to use and understand, with 63 per cent feeling that the device promoted recovery. The team will now conduct a further study to access the impact of GripAble on clinical outcomes.