There are approximately 152,000 strokes occurring in the UK every year and 1.1 million stroke survivors living in the UK. Studies show that stroke is a leading cause of adult disability with more than half of all stroke survivors left dependent on others for everyday activities1. It is further estimated that many thousands suffer with drop foot. Drop foot is the result of missing signals from the brain to the leg muscles responsible for lifting the foot. It is a frequent result of damage to the central nervous system following a stroke and can affect walking ability, confidence and independence.
Current treatment options for such cases are primarily physiotherapy and the use of an ankle-foot orthosis (AFO). Additionally, sometimes adverse tone in the opposing muscle group will negatively affect the recruitment of the Dorsiflexors muscles, in these cases medical intervention such as antispasmodics (botulinum toxin and baclofen) or surgery may be required.
People with drop foot tend to scuff their toes along the ground, so they may lift their foot higher than usual using their pelvis or trunk, or swing the leg from the hip when walking to prevent this. Such compensations can have a negative impact on walking speed, efficiency and balance. Walking with drop foot can therefore require full concentration and any small obstacles could mean a stumble, a very frustrating reminder of the condition in every step.
Ottobock, a supplier of innovative solutions for people with limited mobility offers a full range of solution for clinicians treating patients with drop foot – including recent advances in Functional Electrical Stimulation (FES) device technology.
Standard of Care – Orthotic Solutions
The WalkOn range of carbon fibre AFOs are designed to address the specific needs of each patient and a variety of conditions and degrees of paralysis in the lower limb can be treated. The primary feature of the WalkOn orthoses is that they are dynamic – a particular benefit for patients with permanent dorsiflexor weakness. The latest product to join the range, the WalkOn Reaction, is a lightweight, low profile AFO. Due to its unique anatomical design and quality carbon fibre prepreg material, the WalkOn Reaction allows users to walk naturally and in addition to supporting dorsiflexion, employs ground reaction forces to influence the knee and ankle joint.
Functional Electrical Stimulation (FES)
Functional electrical stimulation (FES) is a treatment that uses the application of small electrical pulses to improve mobility in a number of conditions, particularly for the treatment of drop foot. FES systems use electrical impulses to stimulate the nervous system which, in turn, activates the necessary muscles. It has been used in medicine for decades, including for rehabilitation after a stroke or for patients with multiple sclerosis, and it can also be used to improve mobility on an ongoing basis.
How FES works
FES can either work indirectly, with electrodes placed on the surface of the skin, or directly on the nerves using implanted electrodes. When the foot is lifted, a switch under your heel transmits a wireless signal to a stimulator, which in turn activates nerve pathways controlling the muscles of the lower leg. This provides a controlled lifting of the foot and toes at the right moment. The result is a smoother, safer and faster gait, and a reduced risk of falling.
The MyGait system is the latest addition to external FES devices. It is a cuff-based system, triggered with a wireless heel switch and adjusted through a wireless remote control, making it suited for independent use by patients. The introduction of the MyGait system has also enabled clinicians to use FES during the rehabilitation phase and gait retraining. With its unique cuff design and the possibility to stimulate additional muscles through a second stimulation channel, it provides unique advantages for versatile application and additional therapy options (e.g. support at the hip and knee).
The partly implantable ActiGait system operates through a number of components: an implanted stimulator and cuff electrode, an external control unit, antenna and wireless heel switch. With the surgically implanted electrode, an optimal electrode position is achieved, eliminating the need for daily placement of external electrodes, yet maintaining a consistent foot and ankle movement. This also eliminates the small risk of skin and soft tissue irritation due to surface electrodes. Additional benefits are better sensation and comfort, improved ease of use and cosmetic appearance. The ActiGait system has recently benefited from a redesign of all external components with focus on improved user comfort and usability. Combined with the first evidence from patients continuing to successfully use the system 10 years post-implantation, ActiGait is a durable and effective long-term solution for people living with drop foot as a result of their stroke.
Case Study – Lida Litras
More than 14 years after her stroke, Lida, pictured, can now walk effortlessly and without pain thanks to ActiGait, the implantable Functional Electrical Stimulation (FES) device.
“At the age of 33 in January 1998 and a single mother of two young children, I suffered a devastating stroke. Following a five month hospital stay and after extensive physiotherapy I returned home but struggled to remain independent and found it difficult to get used to my new life. I was forced to leave my job as a property lawyer and my parents, who had emigrated to Cyprus, had to return to England to help me look after my children.
“Following extensive research into new technologies, in December 2011 at the age of 47, I was invited by my consultant at BMI The Blackheath Hospital to trial a new implantable ActiGait FES implant device. I was so excited – it was the answer I had been waiting for.
“After having the device surgically implanted into my thigh, I immediately got used to ActiGait. It takes a couple of seconds to turn on and since the operation I can walk unaided and effortlessly and have no pain whatsoever. It’s a million times better than anything I’ve had before, and has become a part of my life.
“Before ActiGait, I had to wear baggy clothes and wasn’t able to wear dresses or skirts due to the embarrassment of visible wires and electrodes on my leg from my old drop foot solution, which made me feel unfeminine.
“My biggest wish is to help other sufferers to the stage I’m now at, living an independent life. Now I have the confidence to go out, dress the way I want and I feel normal again. For the first time in years I can look forward to the summer and wear dresses and sandals again.”
FES is suitable for patients with drop foot caused by central neurological injury (e.g. stroke, MS, TBI, and in some incomplete SCI cases) and is backed by interventional procedural guidance from NICE (IPG278). For cases caused by peripheral nerve injury, other treatment and management options are necessary.
- For more information on Ottobock’s range of innovative solutions that restore mobility, visit www.ottobock.co.uk or follow @ottobockuk