Once upon a time, power assist for manual wheelchairs was dominated by hub-mounted designs incorporated into the wheelchair’s rear wheels.
But over the years, those venerable in-hub systems were joined by power-assist systems that mount to the front or the back of folding or rigid wheelchairs to provide more choices for wheelchair riders and seating teams.
Power assist has grown vigorously, not just in brand names and manufacturer numbers, but in how engineers have envisioned the ideal power-assist system.
Power assist’s many mounting choices
Angela Regier, OT, OTR/L, ATP/SMS, is the senior portfolio marketing manager at Permobil.
“Hub mount, which was the OG and what was available for so long exclusively, was great for those individuals who didn’t have full upper-extremity strength, but they could maybe still do pressure relief on their own,” Regier noted. “They didn’t want to be in a power chair, but they needed something more than just a standard set of wheels. The hub mount was it, and it was great for that scenario.”
Some downsides to those earlier in-hub models — their weight, for example, which made it difficult for riders to independently load and unload their chairs, as well as the width they added to the chair — have been addressed by today’s renditions.
“I remember some restrictions on the amount of camber you could have, which could obviously impact your propulsion with or without your power-assist device,” Regier added. “Those were considerations that were addressed with the rear-mount device.”
Today, some of the best-known power assists — Permobil’s SmartDrive brand, and Sunrise Medical’s newly launched Empulse R90, as two examples — attach to the back of the wheelchair and are designed to easily detach as well. And front-mounted power assist, which lengthens the wheelchair’s footprint while providing greater pulling-from-the-front strength, is also a growing niche.
Jessica Pedersen, OTD, MBA, OTR/L, ATP/SMS, director of clinical education, and Erica Walling, MPT, ATP/SMS, clinical education manager, both of Sunrise Medical USA, said the larger pool of power-assist choices is definitely welcome.
“It is helpful to have options to meet the various needs of individual riders,” they said.
“Different diagnoses and varying levels of upper-extremity function may require different types of power assist. For example, someone with limited upper-extremity strength and impaired hand function may have difficulty gripping the handrims to veer, steer and brake the wheelchair when using a rear-mounted device such as the Empulse R90 or SmartDrive. Instead, the rider with reduced upper-extremity function may have more success with an in-hub power-assist wheel like the QUICKIE Xtenders, Empulse M90 (launched in Australia, launching in the U.S. in 2025), or Alber e-motion, which requires less force to activate and will magnify the rider’s effort to produce the desired power to propel.”
In-hub models have evolved, too. “Hub-powered assistive devices require less force, and newer models have much lighter wheels, which is more conducive to transporting them when they are taken off to be placed in a car,” Pedersen and Walling said. “The option of adding a joystick is a game changer, as it allows a rider with weak upper extremities to stay in a manual wheel-chair. This may be the mode of choice for individuals, young and old, to learn to use a joystick and have self-initiated movement without moving to a power wheelchair.”
Rear-mounted systems, they added, “are great options to help riders traverse long distances and reduce the risk of repetitive strain injuries by maintaining a desired speed without the need for additional pushes. These devices act as a cruise control and significantly reduce the energy required to propel a manual wheelchair.”
While rear-mount and in-hub power-assist systems are relatively inconspicuous, front-mount systems are harder to overlook.
“A front-mounted pull device, such as the Empulse F35 (launched in Europe, launching in the U.S. in 2025), is a fully electric system that lifts the front casters off the ground and allows for easier negotiation of uneven terrain and inclines,” Pedersen and Walling said. “This type of device typically features faster speeds and is great for traveling longer distances in various outdoor environments. With a front-style (pull) device, a rider must have the trunk and arm control to reach up to the tiller to drive the chair.”
Pulling from the front
The U.S. is about to meet another family of front-mounted power-assist devices. Industry veteran Matt Fitman, president of Rehasense USA, is bringing the globally successful Rehasense brand to America. Rehasense’s power-assist brand is the Power Assisted Wheelchair System (PAWS).
Asked about who could benefit from a front-mounted power assist, Fitman said, “The basic patient demographic is pretty diverse because of the pull from in front, from the large wheel.”
He used PAWS as an example, noting it “increases the wheel base of the chair and more importantly, it pulls the front casters off the ground, so the PAWS can achieve speeds much higher than if you were to use the front casters and have them in contact with the ground with a much shorter wheel base.
“When it comes down to uneven terrain or off pavement, it has the advantage because anytime you have a 5″ or smaller front caster wheel, its relation to terrain becomes pretty difficult. You still feel every bump and vibration. That’s the big advantage to pulling from in front. Anytime distance and speed and terrain come into the equation, there’s a distinct advantage of being pulled from in front and getting those casters off the ground.”
Changing client perspectives
Regardless of their physical forms, all power-assist systems are designed to reduce the physical effort required to self propel a manual wheelchair.
Pedersen and Walling provided a long list of clinical and functional justifications for power assist:
• Inability to manage functional distances/ speed due to upper-limb weakness.
• Pain or range-of-motion limitations.
• Upper-limb dyskinesia that prevents functional wheelchair propulsion.
• Pain with propulsion that limits the ability to meet functional goals.
• Inability to manage functional endurance demands due to comorbidities such as cardiovascular issues/cancer/diabetes.
• Inability to manage inclines and uneven terrain.
• Difficulty or inability to cross a street in a safe and functional time frame.
• History of repetitive strain injury, such as tendinitis, rotator cuff injury, bursitis.
• Inability to carry items during propulsion.
• Experiencing fatigue throughout the day.
• Asymmetrical ability with the upper extremities.
Power assist can address present and future needs by improving propulsion efficiency and potentially reducing risk of future injuries to shoulders, arms and hands.
Yet despite its enormous proactive potential, power assist has been a tough sell to many ultralightweight wheelchair riders who have prided themselves on self propelling without help, often for decades.
That mindset has extended to clients with tetraplegia, known in the past by the nickname “super quads” due to their determination to self propel despite their higher levels of spinal cord injury.
It was a perspective, Fitman recalled, echoed by some health-care professionals. “They told individuals with tetraplegia that they needed to roll and push: ‘You don’t want to lose it,’ and everything else.
“But we know full well that the shoulders were not built as a joint that moves a person through their environment. It’s not built for that. It has distinct disadvantages compared to a hip.”
Working as an ATP at the time, Fitman said he encouraged self propellers, especially those with tetraplegia, to consider alternatives. “Back in the day, I always talked to people: Go find a used power chair. You can get them very cheaply. Because if you’re going to the museum with your family, what are you going to feel like when you get to that museum finally, after pushing for a mile or half a mile from where you parked to get into that facility?”
And as power-assist choices expand, Fitman said he’s seeing client perspectives expand as well.
“I see the shift going on now,” he said. “Once you tell them the possibilities, they get that ‘light bulb’ moment. Where it really becomes interesting is pediatrics, because parents really recognize the difference very quickly: ‘I want my child to be able to go out and take a bike ride with their friends. They can’t do that. But I want them to be able to go to school and be able to get out to recess as quickly as everyone else.’ The most progressive segment of our industry is pediatrics, because parents see the benefit. Parents want the best quality of life.”
Taking time to play the long game
When clients are newly diagnosed — such as with new spinal cord injuries — Regier acknowledged they might not always be immediately receptive to power-assist conversations.
“A lot of times, people don’t want to be in a chair, period,” she said of their reluctance to talk about power assist. But generally, “I would say yes, I think people are definitely getting more proactive. And there are just so many more options now that don’t have such a significant impact on the vehicle situation and all of those things to consider. It can be more modular. You can use it when you want it, not when you don’t.”
Regier added that some resistance to additional equipment is to be expected: “Everyone always wants to use the least amount of equipment to help them feel as ‘normal’ as possible. I remember when I [worked] in rehab, everyone wanted something more. Patients on the ventilator just wanted to be off the vent. The C4 quad just wanted to be able to use a joystick, and the C5 quad just wanted [an ultralightweight wheelchair]. I’m sure that still happens and is still part of the discussion.”
So we’re not to the point where all newly injured spinal cord injury clients are embracing the idea of power assist. “But I feel like it’s more proactively discussed as an option early and often,” Regier said. “And hopefully, it’s one of those things where sometimes it’s a long game.
Particularly if it’s someone who’s been in a chair for a long time, it might take two, three, four or five years to have that discussion from a clinical perspective, where you can say, ‘Hey, have we thought about this? Let’s just try it this year.’ Or ‘How about we come back to it next year?’ Ultimately, we hope they’ll make the decision to give it a go.
“I don’t think that dynamic [of resistance to power assist] will ever be totally gone. But I think we’ve made good progress. I would say since I started as a clinician, 17 or 18 years ago, I think it’s definitely shifted for the better. It’s just going to take time, I think. But there’s more options, which is nice.”
Supporting reimbursement for outside the home
As for changing that other perspective — that of the funding sources — Fitman would especially like to see Medicare’s Complex Rehab Technology benefit expand from the current “in the home” coverage to outside the home, as well.
“How much of life happens outside your home?” he asked. “That’s really the benefit of [power assist]. But I think we’re seeing a shift from people that get the idea that for a well-rounded human experience and to be living rather than just being alive, these changes are very important. It’s being able to go to the right tool in the toolbox for what you choose to be doing with your time and your day. It’s having the tool that will do that best. This rule of what’s medically necessary in the home: Well, what about oxygen concentrators? You’re only going to pay for it if I don’t leave my house?”
Going outside their homes and into the whole wide world is exactly the future Fitman imagines for clients empowered by power assist. “[Power assist] expands people’s worlds, when you can get out there and be in community. Human beings are not isolated individuals. We’re very much community-based beings that need involvement with other human beings to have a better quality of life.”
This story was originally published in Mobility Management’s December ebook digital edition, which focused on manual wheelchairs. For more about power assist, including currently available power-assist systems, check out the ebook.