In the 1980s, Action Medical Research funding helped develop a unique posture support system. More than 25 years on, the ‘Matrix’ system has benefited tens of thousands of disabled children and adults, and is still helping people like 14-year-old Kate today.

The Matrix structure is composed of interlocking nodes and links and can be shaped to the individual user

Wheelchairs provide an invaluable means of support and mobility for many but a standard wheelchair seat may not always be suitable for people with serious disability, especially children. In 1980, Dr Steven Cousins and Professor Tom Lambert approached Action Medical Research with their concept for a revolutionary new posture support system.Their innovative work, supported with grants of more than £75,000 from the Charity, led to the development of the ‘Matrix’. Children, and indeed adults, with physical disabilities often need a form of body support, or seating, to help them perform daily activities.Those with severe disabilities will need posture support to communicate, learn, play and eat. Body supports can be made in various ways, but if a seat does not fit properly it can cause painful pressure sores. For some disabled children, ill-fitting seating can lead to an increase in spinal deformity that may eventually require surgery, while a welldesigned, effective support could prevent these complications and also improve a child’s breathing and help to control muscle spasms.

Award-winning design
The research team behind the Matrix was based at University College London’s Department of Mechanical Engineering, which Professor Lambert headed up. Dr Cousins led the design of the system and is still working to push the boundaries of rehabilitation engineering today. The researchers understood that each disabled child was different.They believed that their unique, ‘shapeable’ Matrix design could allow effective shaping of a chair, or other body support, to individual children. The Matrix is a structure composed of nodes and links in an interlocking design. The individual parts are adjustable, so they can be tweaked to create the desired overall shape and then ‘locked’ to form a rigid support surface. A cushioning cover is then put over the final structure to provide a soft surface for the user. The versatility of the Matrix means that the seat shape can be changed as needed, which is particularly beneficial for growing children and saves money as seats do not need regular replacing. With their funding from Action Medical Research, the engineers improved their initial pilot design.They also expanded the range of the Matrix for different age groups, and assessed its clinical application. The brilliance and originality of Dr Cousins’ work was recognised by the Design Council in 1986, when the Matrix system won a Design Award as “an outstanding British product”, presented by our patron, HRH the Duke of Edinburgh. Action Medical Research again supported the team from 1985 to 1988 as they worked on a miniaturised form of the Matrix structure.This was to offer a tighter contour for very small children and would also be used to make orthoses to support different parts of the body, such as individual limbs or the neck. By now, using Matrix components, patients of any shape or size could be offered bespoke support tailored to their needs.

Despite her condition, Kate is a normal teenage girl who likes to look her best. The Matrix system means she can now choose clothes to suit her, not her spinal jacket

Worldwide success
This pioneering work has had amazing success, with 30,000 people around the world fitted for systems during the past 25 years. Dr Cousins is now Head of Biomedical Engineering at the Royal Hospital for Neuro-disability dealing with adults with severe and complex neurodisability. He estimates that their seating unit alone fits the Matrix system for about 50—60 patients per year. In total, there are around 160 wheelchair seating services and related assessment centres in the UK, and most of these offer Matrix seating. In recent years, Dr Cousins has worked on a ‘2nd generation’ Matrix system, with flexible components that can actually help correct spinal deformity. Seating has not previously been able to accomplish this successfully and the only real option was to use a spinal jacket. Looking forward, Dr Cousins and his team are training wheelchair seating service providers to fit the newest Matrix equipment, so that it can be accessible to more people across the country.

Supporting Kate
Fourteen-year-old Kate has congenital muscular dystrophy, an inherited muscle disorder.The type she has is known as merosin negative — merosin being a protein that is missing in her muscles. She is almost totally dependent on her electric wheelchair and, since the condition affects all muscles, her respiratory system is also compromised. At night she uses a BiPAP, a positive airway pressure machine, to support her breathing, which directly affects the energy she has during the following day. She has also had a gastrostomy, a surgical procedure to insert a feeding tube directly into her stomach to ensure she gets the appropriate level of nutrition. Within a year of being diagnosed with the condition at two-and-a-half, Kate, from Berkshire, had her first spinal jacket made to support her spine. Kate’s mum, Jane, explains, “The maintenance of Kate’s spine is crucial because her muscles are so weak. With the effects of gravity and sitting, she hasn’t got the ability to maintain a straight back, which has resulted in a curvature of the spine, also known as a scoliosis. Without doing anything to support her back, Kate’s respiratory condition would also be dramatically affected.” While the spinal jacket played a vital role in helping to maintain Kate’s spine as she grew, it was not without its problems. These included painful pressure markings, which increased over a period of time as Kate’s spine was pressing into the jacket. Temperature regulation was an issue, especially in the summer when it was hot and the jacket became almost unbearably uncomfortable. Finding clothes she liked was difficult — she had to buy everything one size bigger to get it on over the jacket, and when you’re becoming a teenager who wants to wear the latest high street fashions this can be very hard. The other major benefit the Matrix seat offers Kate and her family is that it is preventing the further deterioration of her spine, reducing the need for risky spinal surgery in the near future. Through the wheelchair clinic she was attending, Kate came to the attention of Dr Steve Cousins, and in June 2006, after nine months work by Dr Cousins and his team, she had her final fitting for her Matrix seat. She was, in fact, one of the first patients to be fitted with a second generation dynamic Matrix seat, which creates directional forces to give her the high level of support her spine needs. “The most important function of the Matrix is to support Kate’s spine and prevent further deterioration of her curves, but not having to wear a spinal jacket has in itself been very significant in Kate’s life,” says Jane.”Now we’ve got rid of the jacket she’s more comfortable, because there are no pressure sore areas, and she has fewer problems with body temperature. Also, as a main carer to Kate, the Matrix eases some of the difficulties in her handling, improving her general care. Placing and removing the jacket with an older child was getting physically harder for me, causing her much discomfort. I couldn’t imagine not having the Matrix seat now — life would be regressive without it.” Kate herself says, “The Matrix has really helped me, as I don’t have to wear my brace any more, and more variety of clothing is possible for me now. It feels like the Matrix has reversed some of the curve in my spine.” “Two days after Kate got her Matrix we went to her school’s summer fete and she was just so happy,” recalls Jane. “She was properly supported, her back didn’t hurt as much, she could breathe properly, hold her head and she felt she had more energy. It was instant joy for her. She had a huge smile on her face.” Having the support she needs means that Kate can sit in her chair more comfortably and this gives her more freedom to do some of the things other children her age take for granted. She has special equipment for school and uses a mouse to write on an onscreen computer. “She’s quite artistic and loves using a programme called Paint to produce amazing pictures,” says Jane, “which again, she couldn’t do without the support of the Matrix.” She also goes to Guides and takes part in a disabled sport called BOCCIA, which is a bit like French boules. “The Matrix seat has been a crucial element in maintaining Kate’s health and quality of life,” concludes Jane.