Page 18 - Mobility Management, January/February 2020

ATP Series
Midline Matters: Power Chair Controls’ Location
of Active Controls, noted that this tendency can also present in wheelchair users with other diagnoses.
“That rule really applies to all of the neurological disabilities,” Flowers said. “It’s not really restricted to any particular one.”
Active Controls is best known for its centrally located power wheelchair driving controls — controls positioned not on the end of an armrest, which is the standard joystick location, but closer to the power chair user’s core or midline.
“It was serendipitous,” Flowers said of finding that midline location. “We had developed the JoyBar handlebar control” — a power chair control that looks like a scooter tiller — “and the only way to put a handlebar control on a power wheelchair is to put it at midline, just like a scooter handlebar is always in the center of the front of the scooter.”
After developing a modular system for that handlebar control, Flowers recalls saying to a colleague, “This is just a connection. We can put any type of control up here, including a joystick.” That colleague responded, “If we can do a joystick, we can do alternative driving controls.”
Flowers added that there’s a very practical reason that midline- mounted controls can be easier for some power chair users to operate. As Active Controls was designing its products, Flowers noted, “I said, ‘If we do a joystick, we can do supports on each side
of the joystick to support the lower arm and relieve the stress and the strain on the forearm and the heel of the hand.’ That would make it so much easier to drive a power wheelchair. That’s how it all evolved.
“When we did that and developed the gel pads for [the supports], we found that [midline controls are] not just for
people who can’t drive from the armrests. By supporting the
lower arm and the heel of the hand, you are using less muscles. We confirmed that with the clinical study we did at MossRehab Hospital [available on the www.ActiveControls.com Web site]. The doctor who did the study [Alberto Esquenazi, M.D., MossRehab] used muscle sensors to see which muscles were firing when you drive from an armrest, and then he compared it to driving at midline with lower-arm supports. And he confirmed that the muscles that fire are basically in the shoulder and the neck — so that’s your trapezoids. And it confirmed that you have less muscle usage when you drive at midline with a lower-arm support. That equals less fatigue and longer [power chair] usage during the day.”
Variations on the Midline Location
So if operating a joystick or other power chair driving control from a midline location can require less effort and cause less fatigue, why not just move all power chair driving controls front and center?
Because, as is seemingly always the case with complex rehab
16 JANUARY/FEBRUARY2020|MOBILITYMANAGEMENT
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