Sensorimotor rehabilitation of paralysed fingers
Some 30% of stroke survivors suffer from severe upper limb paresis with a non-functioning hand and the outcomes for rehab, at least in the research literature, seem to be poor. It's not so long ago that there were relatively few products available for hand and arm rehab. It was interesting to see at the recent European Neurorehab Expo that the pendulum has definitely swung the other way with lots of product offerings now deploying various technologies - Virtual reality, gaming, FES, robotics and so on. The challenge is now more about working out when a particular product would be helpful for an individual patient.
A few years ago it was common for someone to phone our office and say, "I have had a stroke and I got some walking therapy in hospital but no one bothered about my arm. Is there anything I can do about it? Nowadays the question might be more like "Will product X help my arm and hand?" and of course the correct answer is "We don't know - you need to be properly assessed first."
Actually, even that is not the complete answer because it can often be very hard to forsee the outcome from using a particular product. Therapists understandably don't know all the products that are available and non of us can have bulletproof ideas about the dose (frequency and intensity) of rehab needed to make a difference in a particular case.
My old Professor, Robert Kenedi used to talk about the need for technology to produce the Minimum Change Capable of Changing a Clinicians Mind. Whatever we do, we need to make an impact and that is so often uncertain when we start down the rehab path. As a business we believe in the power of technology harnessed as a tool alongside intelligently applied therapy. There are no perfect therapists or perfect products but when you have a complementary blend of both great things can happen.
The research literature is often a poor guide to what actually makes an impact unless we are sure that increasing the frequency and intensity of the intervention wouldn't make a difference. So often I hear people say "Im getting hand therapy once a week for 40 minutes" and I suspect that this may not be enough to change very much in terms of the client's status but I cant always be certain that a particular intervention five times per week solves the problem.
We have a new product from our partners Hasomed GmbH and it's a refinement of some hardware described in the paper by Hesse et al (2008). They describe what has become RehaDigit applied in a study with chronic and sub-aacute stroke patients.
The RehaDigit is a novel device for repeating controlled passive movements of paralysed fingers with the aim of allowing therapists to concentrate on more complicated tasks whilst allowing more intensive therapy. The device moves the four fingers over a physiological range of movement whilst adding a controlled vibration to activate the sensorimotor system.
After refining the training protocol with 2 chronic stroke patients, 8 sub-acute stroke patients were randomised to receive additional therapy with the predecessor to the RehaDigit for 20 min every work day for four weeks, or the same duration of bimanual group therapy, in addition to their usual rehabilitation.
In the chronic patients, there was a sustained reduction in finger and wrist spasticity, but there was no improvement in active movements. In the subacute patients, mean distal Fugl-Meyer score (0–30) increased in the control group from 1.25 to 2.75 (ns) and 0.75 to 6.75 in the treatment group (p < .05). Median Modified Ashworth score increased 0/5 to 2/5 in the control group, but not in the treatment group, 0 to 0. Only one patient, in the treatment group, regained function of the affected hand. No side effects occurred.
Treatment was well tolerated in sub-acute & chronic stroke patients, whose abnormal muscle tone improved. In sub-acute stroke patients, the group showed small improvements in active movement and avoided the increase in tone seen in the control group. This series was too small to demonstrate any effect on overall functional outcome however.
We have only had this product for a week or so and early feedback from clinicians has been excellent.