A Clinician's Perspective on ALS: An 80/20 Strategy
- By Laurie Watanabe
- Jun 01, 2022
Seating and wheeled mobility clients are as unique as snowflakes.
Each client has unique goals, activities, and priorities… and their
functional presentations vary widely, even if formal diagnoses are
That individuality impacts their seating and wheeled mobility.
It’s a common Complex Rehab saying that no two wheelchairs are
exactly alike. Even when the power wheelchair base is the same,
how various components are positioned and dialed in makes every
system unique unto itself.
The need for unique power wheelchairs would seem to be a given
for clients with amyotrophic lateral sclerosis (ALS). The progressive
degeneration of motor neurons that enable voluntary muscle
movement eventually robs clients of the ability to walk, talk, swallow
and breathe. ALS would seem the perfect example of a condition that
needs a “snowflake” seating and mobility approach.
But what if you found enough commonality among ALS clients
to home in on the options they most frequently require on their
power chairs? If you could anticipate their needs, could you
simplify the building and provision process — and get the optimal
equipment to these clients faster?
It’s a process that Steve Mitchell, OTR/L, ATP, refers to as
creating ice cubes instead of snowflakes.
A Presumption of Service Connection at the VA
Mitchell is an occupational therapist who works as a Clinical
Specialist in seating/wheeled mobility and assistive technology
for the Spinal Cord Injury & Disorders Service at the Cleveland
Veterans Affairs (VA) Medical Center.
As one of “just a handful,” he said, of VA therapists who are fulltime
seating specialists, Mitchell focuses exclusively on veterans
with spinal cord injury/disorders (SCI/D) and veterans with ALS.
In 2016, he wrote a series of Mobility Management articles on the
concept of “Open CRT” — explaining that he’d found enough
similarities among his ALS clients to see patterns not just in the
seating and mobility they needed immediately, but what they were
likely to need as the ALS progressed.
In talking with Mobility Management this time, Mitchell
expanded on his “80/20” approach.
His specialization significantly narrows the range of clients
he sees. “The veteran I’m working with is typically going to be a
male,” Mitchell said. “They’re going to be roughly 6'0" tall, give or
take 3" or 4".” Their weight, he added, usually falls within the same
range, “give or take 20 or 30 pounds. We see some female veterans,
but we don’t see that many.”
Because most of his clients fall into a relatively narrow size
range, “I don’t have to worry about the size of the seat, and there’s
enough modularity in today’s designs where you can make those
adjustments. So I can really home in on the details. That’s where
the big-picture success is, in execution of the details. And there are
so many characteristics that my populations have in common that
I can really home in on those and address those.”
One fact is well known: On its Web site, the ALS Association
states, “Military veterans, regardless of the branch of service, the
era in which they served, or whether they served during a time of peace or a time of war, are at a greater risk of dying from ALS than
if they had not served in the military. For reasons as yet unknown,
veterans are twice as likely to be diagnosed with ALS as the general
population.” Multiple studies affirming the higher ALS risk for
veterans led the VA to implement, in 2008, a “presumption of
service connection” for ALS. That declaration “presumes that ALS
was incurred or aggravated by a veteran’s service in the military.”
At that time, Mitchell was predominantly working with veterans
with SCI or advanced multiple sclerosis. “But once [the ALS presumptive
service connection] became part of the equation, we started
our multi-disciplinary ALS clinic. We were the first VA to become a
Certified Clinical Center of Excellence by the ALS Association.”
Seeing the Patterns
In focusing on this relatively narrow band of ALS clients, Mitchell
saw patterns emerging.
“Somebody with a spinal cord injury is going to be relatively
stable,” he explained. “If I accomplish my goals as an occupational
therapist and dial in the [wheelchair and seating] configuration
for optimal function — it inherently requires a lot of attention to
detail. It’s a snowflake, of course. But once I had it dialed in, it was
That wasn’t the case with ALS clients.
“What I began noticing is that veterans with certain functional
presentations of ALS tended to experience many of the same problems,”
he said. “I also realized that many of these problems weren’t
going to die with the first user who had experienced them. I would
see them again and again.” Many of these problems were directly
related to gravity. Finding ways to effectively mitigate the effects of
gravity on a user’s posture, positioning, and function is a continual
challenge for any seating clinician who works with this population.
“As I came up with effective solutions to these problems in my
clinic, it didn’t make sense to have to re-create the same configuration
from scratch for every veteran who shared a given presentation.”
Instead of delegating the job to the DME supplier he worked with,
Mitchell looked for a more efficient process. “I began sending pictures
to the manufacturers to see if they could replicate a given solution
as a custom option,” he said. “And that’s evolved nicely over the
years. Our ALS power chairs now come with a modular, adaptable
infrastructure that allows us to really dial in the configuration so that
it effectively meets their clinical and functional needs. As those needs
change, the same options will allow us to reconfigure a chair so that
the veteran can continue using it for as long as possible.”
The 80/20 Strategy
Although Mitchell initially developed the custom options to address
the most frequent issues he saw in his clinic, he also encountered
more challenging issues in subsets of veterans who shared specific
functional presentations of the disease. This led to what he refers to
as his “80/20” approach to ALS power chair configuration.
“Without getting too technical,” he explained, “I have found that
nearly every veteran who could use a conventional joystick during
their initial evaluation continued to be able to use a joystick for as
long as they had their chair. Only 20 percent of the veterans we
followed with ALS needed to use alternative controls. What’s more,
we were fairly successful at predicting which veterans would need
these systems at the time of their initial evaluation. While there have
been some exceptions, having this knowledge has allowed me to
develop two different types of ALS custom configurations: one to
effectively meet the needs of the majority of veterans who have ALS,
and another which has been optimized for the important subset of
veterans who needed alternative driving controls.”
Mitchell has discovered a simple test has been a fairly accurate
predictor of which configuration is likely to work better.
“I have them fully tilt back in the chair. If they have enough
function against gravity to easily reach the end of the joystick,
they’ll probably belong to the 80-percent of veterans who will
continue using a joystick. If not, they would be a better candidate
for my Hybrid Alternative Driving System (HADS) configuration.”
On his “80-percent” chairs, proper joystick positioning is key.
“As a rule, you want to provide a ‘low, level and inline’ joystick
configuration,” Mitchell said. “These users tend to do best when
the joystick is located directly in front of the armrest — no higher
than 2" to 3" above the surface of the arm pad. The armrest itself
should be parallel to the seat surface at the back angle they need
to breathe comfortably and have postural stability. Clinically, the
objective is to minimize the need to use anti-gravity movement by
providing uniform support along the entire length of the forearm.
The armrest and joystick are basically configured so that if
someone has full range against gravity, but can’t tolerate resistance,
they will still be able to operate the joystick and power seating
For the remaining 20 percent of veterans, Mitchell said, “Their
ALS typically affects both upper extremities first. Most will have
very good lower-extremity function. They may also have fairly
good head control or oral motor function that can be taken advantage
of. These individuals tend to progress a little more slowly,
which is good because their chairs typically take a bit longer to
“Oftentimes, these users will start out using a compact joystick
with the same low, level, and inline configuration. Some may
continue using the compact joystick for some time. A few may
never go on to use a hybrid system, but should we need to make
that transition, that infrastructure is already there.”
Instead of using head arrays or other typical alternative controls,
Mitchell has combined his clinical understanding of ALS with his
years of providing conventional systems to develop a somewhat
unconventional approach to providing alternative driving controls.
“To receive a diagnosis of ALS, there must be signs of upper
and motor neuron dysfunction in three out of four segments of the
nervous system,” he explained. “There’s probably not a single body
part that’s left unaffected by the time they come to my clinic.
“Conversely, conventional alternative controls generally require
very good use of a single body part. To effectively meet the needs of
these users, we need to be able to customize systems to take advantage
of whatever function they have. Implementing such systems
can be done most easily by using a simple switched driving
interface, a power seating switch interface, and a simple network of
color-coded extension cables. If this infrastructure is already on a
power chair, it becomes possible to implement a Hybrid Alternative
Driving System with far less time, labor, and technical expertise
than would otherwise be the case. It’s simply a matter of finding the right combination of switches.”
And regarding mini joysticks: “I have had a few people with ALS
[for whom] I’ve used mini joysticks, but I think those tend to be
the most beneficial for people who have muscular dystrophy and
other conditions that affect distal movement. If the muscles can’t
overcome the weight of the arm against gravity, taking a couple of
ounces off the amount of effort required to move the joystick isn’t
going to make a world of difference. So we normally prescribe a
compact joystick with the same effort that the [standard] joystick
has. It generally works pretty well.”
What Ice Cubes Can Accomplish
There are big upsides to building adaptable wheelchairs.
“One of the benefits is it’s making an ice cube instead of a snowflake,
so you can adapt it as the illness progresses,” Mitchell said.
“It’s one of the things that’s been really helpful and allows us to
serve the needs of veterans better.
“Anytime we provide equipment to a veteran, it’s theirs to keep.
But if it’s in good condition and we do get it back, those options
that made it easier to configure for their needs also make it easier
to reconfigure for another veteran. So we tell our veterans that
up front, and if we do get a chair back that’s in good condition,
sometimes we can quickly reconfigure and reissue it, and save the
person the time that’s usually required to order something new.”
Keeping It Simple
Mitchell acknowledged that the 80/20 approach doesn’t fit every
ALS client. “They’re not all the Cleveland VA custom configuration,
these ice cubes that I do,” he said. “We do get people that are going
to be exceptions. And then we might go more along the traditional
Complex Rehab route, where it’s more like a spinal cord [injury]
chair, especially if we know that their condition’s progressing
pretty slowly and they’re younger.
“Others who unfortunately progress more rapidly are more
urgent as far as giving them something. That’s where reconfigured
chairs are helpful. Odds are [ALS is] probably not going to all of a
sudden plateau to where their condition’s not going to change.”
While Mitchell’s approach is different from what you might
expect for ALS clients, he said his approach is actually simple.
“Even for the 20-percent chairs: Those are going to take a little
bit more work, but even then, I’m using mechanical switches,” he
said. “I’m not using sensors. I haven’t done a head array in probably
10 years, and I’m getting good outcomes.
“These are really easy solutions. It’s custom, but not that complicated.
It’s simple. It’s been so rewarding.”
Editor’s note: Steve Mitchell’s opinions do not constitute an endorsement of
any specific product, nor do they represent the official policy or positions of the
Department of Veterans Affairs.
This article originally appeared in the May/Jun 2022 issue of Mobility Management.