What Drives Them?

Switch or Proportional: Choosing What Works for Very Young Power Chair Users

Switch or ProportionalWorking with very young seating & mobility clients can be a “tabula rasa” experience. Clinicians and providers get to start with a blank slate: Here’s a client with little or no previously prescribed equipment to wonder about, and no preconceived notions about what might or might not work.

The flip side? Very young clients — who could be less than 12 months old — probably can’t offer detailed explanations of what they like or don’t like. They also don’t have long histories for their rehab team to draw on when determining a course of action.

Nonetheless, thanks to ongoing research and advocacy, independent mobility is a possibility for more and more very young kids — and at earlier ages than ever before. For these children, power mobility is their first foray into the wide world that awaits them. But to venture into the world, they need a vehicle to get there.

How will that vehicle be equipped — with proportional drive controls? Or switches?

Early-Intervention: Who Can Benefit?

For this story, we called upon the following pediatric seating & mobility experts (listed alphabetically):

  • Ryan Hagy, OTR/L, ATP, sales director of western United States, Quantum Rehab
  • Karen Kangas, OTR/L, private practice
  • Christopher Ligi, national sales manager, Switch-It
  • Amy Morgan, PT, ATP, pediatric & standing specialist, Permobil
  • Lisa Rotelli, VP, Adaptive Switch Labs

Our first question: Which diagnoses are providers and clinicians most likely to encounter when working with very young candidates for power mobility?

Christopher Ligi says it’s a mistake to put too much emphasis on the diagnosis when determining whether a young child could benefit from power mobility: “It’s always an individual decision,” he notes. But typical diagnoses that providers and clinicians could expect to see include “various levels of cerebral palsy; spinal muscular atrophy (SMA); arthrogryposis; osteogenesis imperfecta; spinal cord injuries; muscular dystrophy.”

Says Ryan Hagy, “When I’m thinking of very young children driving, I’m thinking of 12 to 18 months old, and typically you’ll see spinal muscular atrophy, because they’re usually at or above age-appropriate cognition or intelligence.” Other possibilities, he says, are “depending on the level of their involvement, kids with cerebral palsy (CP), spina bifida, and spinal cord injury, usually from motor vehicle accidents.”

Amy Morgan has seen early-intervention power mobility provided to children with congenital static encephalopathy, as well as other more generic diagnoses. “A lot of times,” she says, “they don’t get the diagnosis of CP until they’re older. So they have these general diagnoses of developmental delay, or something like that.”

And while those diagnoses are the most common ones that pediatric teams see when assessing for early-intervention power, all of our experts emphasized the need to look beyond a black-and-white diagnosis when determining which children could benefit.

Karen Kangas, for instance, says she sees a child’s lack of mobility as being a crucial criterion for needing power mobility.

“For me as a pediatric therapist, I am interested in all young children being independently and functionally mobile,” she explains. “Since many young children with disabilities are not mobile, their development is truly vulnerable in all areas — cognitive, social, intellectual, emotional, language, visual-perceptual — if they are unable to move around within their environment.

“I feel that all young children who are not independently mobile really need powered mobility and need to be considered candidates for it. The more complex the body of the child — the more tone, etc. — the more medical fragility they appear to demonstrate. The skill of the therapist and the rehab supplier must be greater to find equipment which will truly ‘match’ the needs and skills of these children with the more complex bodies.”

Pre-Requisites to Independent Mobility

Now that some children are being given access to power mobility before their first birthdays — the University of Delaware’s Cole Galloway, Ph.D., is known for starting to teach some children to operate power mobility vehicles at the age of 7 months — the next question is what skills or understanding children need to be able to operate power chairs effectively.

Our experts mentioned that understanding cause and effect — that interacting with a switch or a proportional device makes the chair move — has traditionally been considered a mandatory skill to operate power chairs well.

But they also questioned how true that belief is.

“The biggest issue I have with these pre-requisites or qualifications (the children) must have is we feel they have to be present before we get them in a chair,” Morgan says. “A lot of times, we don’t see the cause-and-effect skill develop until we give them the opportunity to use the chair. So it’s not a ‘Have cause-and-effect, then you get to try a power chair.’”

Instead, she says, a better model would be allowing the child to sit in the power chair to develop his cause-and-effect skills.

Hagy says the lack of cause-and-effect understanding shouldn’t exclude a child from being a good candidate for power mobility. “If they don’t have it — that’s a goal I used to work on in therapy,” he says. “That’s a great thing for parents to work on in a home program, or OTs and PTs to have a goal in therapy as far as starting to use switch toys, starting to use different things to help the client work on cause and effect.”

Hagy also says a child needs to want to be mobile, but he adds, “With the adult population when going into a chair, sometimes the technology can be overwhelming. They have pre-conceived notions about what is acceptable and what isn’t in society, so they can be more resistant. Whereas kids just want to go, typically. Typically, they have that desire to be mobile.”

In her experience, Kangas says, “I have not found that there are developmental or cognitive pre-requisites. Instead, it is far more critical that the therapists and parents be able to introduce a mobility vehicle within the child’s environment in a way that the child can immediately begin to manage it.”

She acknowledges that asking about pre-requisites is common in the industry, but adds, “I am much more concerned about how the child is mobile. If the child is not able to ambulate, cannot use a walker (or uses it with great challenge) or cannot push a manual wheelchair, then a powered chair needs to be considered for the experience and use of functional independent mobility.”

Part of the problem, Kangas says, is that the process used to assess adults for power mobility will not work when applied to young children. While many adults being assessed have some history of independent mobility, very young children do not.

“Children are not small adults,” she says. “And children who have never had the experience of independent mobility are not going to be successful in assessment and training strategies which have been developed for adults. Children learn and use mobility in familiar environments, and with familiar adults, and are particularly interested in the mobility not as a skill unto itself, but rather as a means to approach a person or object, leave a situation, explore an environment, and/or touch and obtain an object.

“Because many therapists and parents still see a powered chair as a ‘car’ and with ‘driving skills’ needed, they tend to think that pre-requisite skills are needed. But mobility for a child is a gaining of experience, a way to learn about themselves and the world. It is through the use and discovery of mobility that development can progress.

“A child needs to be able to move to learn directionality, needs to be able to approach objects and leave situations, to learn how to do it. The key to a child’s success in the use of powered mobility is the need to support and understand that a child needs to explore mobility first, not driving. Eventually, driving skills will be needed. But initially, this should not be the focus in the use of the powered chair.”

Which Comes First, the Switch or the Joystick?

So should very young children who are learning to operate power chairs be taught using switches or proportional devices? Is a switch — by nature, an “on” or “off” device — easier for children to learn?

Hagy says, “From a true cognitive perspective, yes — because it’s very simplistic. That switch, you push it — it’s on. You let go, and it’s off. It’s very easy to get that, and when you’re switch driving, that switch is related to a fixed speed and a fixed direction, versus a joystick — now you have graded speed, you have 360 degrees of direction. Controlling speed, controlling direction — so many more variables. The switch probably is the direct, easier way to drive. It requires less motor control, and you can probably understand the concept a bit younger than you can with a proportional joystick control.”

As far as which type of driving control to start with, Hagy says, “That’s a tough one, because therapists see it different ways. There’s a group that says cognitively, they’re definitely going to understand the switch first. I’ll start them on one switch, two switches, three switches, four switches, and then once they grasp the switching and multiple directions, I’ll translate that over to a joystick. But then you’re training them on switches first and then training them on joysticks. Some therapists say with, like, kiddos with SMA — if they’re always going to use joysticks anyway, start them on a joystick. It’s going to take them a little longer with trial and error up front, but then once they’ve got it, they’ve got it. So my training time is actually shorter.”

Morgan says a more important factor when deciding between switch and proportional systems is the child’s motor limitations.

“They learn cause and effect whether it’s a proportional device or a switch device,” she notes. “But the reason I would lean toward a switch for a child, for example, with CP who has abnormal tone and is unable to control their arm or their hand in the mid range is (those children) work in extreme ranges. They can’t grade their movement. It’s going to be a lot more difficult for them to learn how to use the chair than if we provided them a single switch or two switches that distinctly go in the direction that they want to go.

“The decision to go proportional or switch is a motor decision much more than a cognitive decision.”

Morgan also says clinicians or providers may feel more comfortable with proportional devices.

“Switches to me are negatively perceived in our community and our industry,” she says. “We prefer joysticks, because joysticks are more standard, so I think we tend to push the joystick on these kids way too much. It’s more frustrating for them. They understand what they want to do and how they’re supposed to do it. Their body is just not cooperating.”

Of the power mobility learning process, Morgan says, “We want it to be as effortless as possible. That’s not to say that a kid that starts with a switch isn’t going to end up using a joystick. Let’s (put) the switches in an array that’s like the movements of a joystick, so we start to train their arm to grade that control within that little space, and then see if we can transition them over to a joystick in the future.”

And switches really are problem-solvers for some drivers, Morgan says. She recalls a little girl she met at an Abilities Expo consumer show a few years ago.

“Her mom came to me and said the therapists have been working for years, trying to get her (daughter) to drive a power chair: ‘We know she wants to do it, and we feel like she can do it, but she’s always looking at her hand on the joystick. She doesn’t raise her head to see where she’s going.’”

“I said, ‘Have they used a head array?’ And she said no. I had one there, so we sat the girl in the chair and started with a single switch to the right and let her just experience stop and go, and cause and effect that way. I quickly saw she was totally understanding it. Then we added forward in the back pad, and she was doing two switches. And not long after, I added a third switch. She was driving completely independently through the Abilities Expo with a three-switch head array in a matter of 15 minutes.

“It’s those kind of kiddos that I think get missed. They get labeled as ‘They’re not going to be safe because they’re not watching where they’re going’ or whatever it might be. We’re just not doing a comprehensive assessment and using the technology that’s available to make them successful.”

Making Mobility Like Child’s Play

Ultimately, whether a chair employs a proportional or a switch device, the goal is to make the mobility system as easy as possible for the child to operate, our experts agreed.

There was also the belief that many times, the biggest obstacles in providing independent mobility to young children are not the disabilities the children might have, but instead, misconceptions among the adults around them.

“I consider every child I meet who is not independently mobile a candidate for power,” Kangas says. “That does not mean that I tell parents that the child should or could or would drive. I know that I can set up a system for a child to exhibit some form of independence.”

“They can be more intuitive about technology than we are sometimes,” Ligi says. “Sometimes the door is shut before they even have a chance.”

Says Morgan, “I think insurance companies are still having a difficult time funding kids that are what I like to call ‘marginally independent,’ meaning they’re developing and learning from the chair, but some insurances and Medicaids want them to be totally independent. And we know children are not totally independent; they’re always supervised.

“We have very high expectations, and unachievable, unattainable expectations for these little children that are just learning the world. We haven’t associated power mobility with the normal walking sequences. It’s definitely going to take some time for that type of mentality and change to happen in our industry and the therapeutic world. I think we should continue to push for that to happen.”

This article originally appeared in the April 2011 issue of Mobility Management.

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