My paralysed foot was brought back to life by a buzzer inside my thigh
21:15 GMT, 7 April 2012
Lida Litras life has been transformed by the ActiGait implant
n electronic implant the size of a matchbox is offering a solution to thousands of Britons who suffer foot paralysis. Foot drop, or drop foot as it is also called, refers to a weakening of the muscles used to flex the ankle and toes. This causes sufferers to drag the front of the affected foot while walking, and they compensate for this by trying to swing the whole leg from the hip.
It is a disorder of the nerves and can be the result of injuries or stroke but is not a disease in itself.
Depending on the cause, foot drop may be temporary and can be helped by physiotherapy, or it may be permanent. In the past, those with untreatable foot drop would have had to wear an ankle brace to hold the foot in a normal position. Now, a British woman has become the first patient in the country to benefit from new technology that promises to restore natural movement to even the most difficult cases.
Lida Litras suffered a stroke when she was just 33, which left her paralysed on her left side. The mother of two from Winchmore Hill, North London, was left hospitalised and wheelchair-bound for five months.
With the help of extensive physiotherapy, Lida returned home. But unable to walk unaided, she found it difficult to get used to her new life.
‘I was fitted with a really big foot brace, so I had to wear a boot two sizes bigger than my normal shoes and I could only wear baggy trousers,’ she recalls.
‘The fact I had to have someone push the wheelchair or help me go to the toilet made life very difficult – I was a young woman. I used to love sport. I didn’t find it easy having to ask for help.’
Lida was forced to give up her job as a property lawyer and her parents, who had emigrated to Cyprus, had to return to England to help look after her children.
In 2004, specialists offered Lida an external device that stimulated the nerves.
It comprised a battery-powered box worn at the waist, connected by wires to two electrodes stuck to the skin below the knee. These were wired to a switch under the heel which sensed when the foot was lifted and when it touched the ground. At the appropriate moment this would substitute missing central nervous system signals, providing the required nerve trigger to allow the correct movement of the foot.
Lida says: ‘It was much better than the foot brace. I put it on and it meant I didn’t have to constantly think about lifting my foot,’ she says. ‘And I was happy going from wearing big bulky boots all year round to using that device. But the wires kept coming undone and I kept breaking electrodes.’
The device also caused a painful feeling in her leg when she walked.
‘If I did a lot of walking I’d have to take it off,’ she says.
Last year she developed a reaction from having the electrodes on her skin for such a long time.
The foot switch can be worn in a sports
sock so the patient can wear normal footwear and, unlike previous
models, there are no wires running down the leg
‘My skin got really bad,’ she says. ‘I had terrible burns and blisters on my leg. It got to the point where I couldn’t use the device because it was so painful.’
Then, in December, Lida was invited by her consultant to trial a new implantable device at BMI The Blackheath Hospital. ‘I was so excited – it was the answer I’d been waiting for,’ she says.
Known as ActiGait, it is controlled by a wireless foot switch, worn under the heel and connected to a component on the ankle. The device triggers stimulation when the foot is lifted, and stops stimulation when the foot is placed on the ground.
The foot switch can be worn in a sports sock so the patient can wear normal footwear and, unlike previous models, there are no wires running down the leg.
Fitting it involves a two-hour operation, during which an electrode is implanted in the muscle slightly above the knee and wrapped around the nerve that feeds the muscle. The stimulator, an electronic chip measuring about 6cm by 3cm, is implanted in the outside of the upper thigh.
Dr Michael Jauch, who carried out Lida’s procedure, says: ‘Between those two, internally, a tunnel is created running from the stimulator down to the electrode, with a cable running between them. ActiGait works on the same principle as the earlier external device, by stimulating the leg muscles, but is far more precise.’
How the implant works
Lida stayed overnight at the hospital and then had a three-week recovery period before the device was activated in a procedure that takes an hour.
A control unit – an external piece of apparatus worn on the patient’s waist-band – is connected to a computer. The consultant uses specialist software to ensure all the settings are correct.
Afterwards, the patient is able to adjust the settings from the control unit should they need to. The implant is powered by the external unit, which is rechargeable. The lifetime of each of the components varies, but the implant is expected to last for at least ten years while the external batteries on the control unit and foot switch typically last up to two years after which they can be replaced.
Lida was astonished to find she was able to walk unaided almost straight away. ‘I couldn’t believe how brilliantly it worked. At home it took about three seconds to switch on, and it stayed working well every day.
‘My old device would start off OK but gradually become less efficient and more painful, whereas this works perfectly all day, every day.’
Lida continues to have physio because she still has problems with other parts of her body, but she says she now finds it much less exhausting. The device can even be adjusted to work during vigorous exercise. Experts believes many more patients will benefit from the ActiGait, which was trialled in Denmark before coming to Britain. The device and all its components, including the cost of surgery, screening, fitting appointments and five years’ service and monitoring, cost about 20,000, or 4,000 a year.
Lida was astonished to find she was able to walk unaided almost straight away
Dr Jauch says: ‘This treatment means patients are able to walk so much better. They regain their confidence because they don’t have to concentrate on every step.’
At the moment it is licensed only for use in stroke sufferers, but Dr Jauch believes there is potential for it to be used by MS sufferers or people who have spinal injuries.
He says: ‘Using the device means patients are less tired, there’s a reduced risk of falling and they can reintegrate much better into their families and home surroundings, and if they are young enough they are able to return to work.’
Physiotherapist Jon Graham, who works with foot drop sufferers, agrees, saying: ‘There are other devices on the market that all have their pace, but for patients with persistent foot drop the ActiGait offers the best solution.’
Lida adds: ‘I can go out by myself, I don’t have to worry about electrodes and wires, and I can wear whatever clothes I want.’
Lida has recently started a new job with a property management company. She says: ‘I’m not back to how I was before but that’s never going to happen, so at least I’m back to as close as I can be to that. I couldn’t really ask for more.’
To find out more about ActiGait, visit ottobock.co.uk.