ATP Series

Justify It: Power or Manual

Determining (& Justifying) the Better Mobility Choice

cervical spinal cord injuries


When working with clients who have lower-cervical spinal cord injuries (SCI) — think of the C5/C6 region — clinicians and ATPs can face a mobility crossroads.

Option 1: Ultralightweight manual mobility that’s self propelled, typically minimalist and elegant in design and appearance, and significantly more capable of fitting into less than ideally accessible environments, including cars and taxicabs. P.S. — they’re also typically less expensive, a detail very meaningful to funding sources.

Option 2: Power mobility, which preserves its user’s energy (and possibly its user’s shoulders) while offering touch-of-abutton powered positioning functions such as tilt to perform critical weight shifts.

Which pathway is better for any given client depends on many variables — clinical and, just as importantly, personal ones.

What Drives the Decision

Curtis Merring, OTR/L, MOT, is now a clinical education manager for Permobil. But as a former director of rehabilitative services, he has years of experience in assessing clients for complex seating and wheeled mobility. Clients have included those with SCI, and those whose level of injury could have indicated either manual self-propelled or power mobility.

“The decision between manual and power always starts with the person and their MRADL [mobility-related activities of daily living] needs,” Merring said. “The process is the same regardless of injury, but there are specific considerations that come up when working with a person with SCI.”

He noted that two clients with the same level of SCI could opt for different equipment choices based on other factors, including “genetic factors beforehand, ADL demands, what do they need to do, what do they want to do.

“We’re designing one wheelchair for one million functions, and each time I do a wheelchair evaluation and a wheelchair design, I’m just trying to eliminate as many trade-offs as possible.”

A Thorough Evaluation

While evaluations of clients with SCI will always include discussion of the levels of injury and incomplete vs. complete injuries, Merring suggested that clinical questions should be only part of the overall conversation that helps to determine whether a client uses manual or power mobility.

“I have an evaluation form that I put together,” he said. “[It starts with] demographics, then insurance information, because those are pertinent, and then diagnosis codes, because that’s going to help us drive funding and figure out what is available when I’m working with the ATP and insurance. But then I’ll ask: What are your life goals? What are you doing every day?”

Newly injured clients come to their assessments while still adjusting to their new lifestyles; they may be full of questions. Clients who have lived with SCI for years might be coming in for assessment prior to ordering their second or third chairs; they may believe they’ve already decided what they want. Merring says the two groups need to be asked different questions.

“For a first-time user, you have to determine what they need to accomplish daily,” he said. “What do they need to get done during the day?” For experienced wheelchair users, “You have to determine what they can accomplish in their current system, and then what more they would like to accomplish from a new or improved seating system. If we were to get you a new seating system or an improved seating system, what don’t you accomplish throughout the day that we can help you accomplish if we applied better technology and better fitting and better posture to the new seating system?”

Answers will vary for a lot of reasons.

“If I’m evaluating a 90-year-old woman who just wants to go from her bedroom to the kitchen and then to watch TV, [that mobility system] may not be something incredibly well designed for 2,000 to 3,000 pushes a day [as you might see for] a very active person, who works full time and is in his or her chair for 10 or 12 hours a day. You have to get that whole idea of what they did before, what they want to be now — and how can we help them with this new device?”

This is a major part of the assessment, Merring pointed out: “You want to get the biggest global picture you can, so that when you’re designing the chair, you really have an idea not just of the physical issues with this person, but what do they like to achieve personally?” He referred to this part of the process as a “conversation,” one that everyone on the seating and mobility team should contribute to.

“As the clinician, I’m the objective observer,” Merring said. “Say Mom’s giving an opinion, and then the 18-year-old young adult [who is the wheelchair user] is giving an opinion, the ATP is giving an opinion. It’s my job to take those parts and try to figure out what’s optimal for this person. Another thing I like to do — and this is why I think multiple [assessment] visits are really important — is maybe in the first one, everyone is there. And then in the second one, it’s just me and the person that’s getting the chair. Then he can say, ‘My mom says this, but I really want to do this.’”

The Mat Evaluation

After one or more conversations about goals and priorities, it’s time for clinical observations. “I like to look at what they’re sitting on now, and see how they propel,” Merring said. “I need to see: What does their pelvis do, what does their spine do, how strong are their arms, can they propel or not, how strong are their legs? And then I seat them on the mat: What is the shape their pelvis takes, the spine takes, the rib cage takes, when gravity starts to take effect? If you have a very tall [client] and a very short one, gravity may affect their thoracic spines differently.”

Merring also uses that time to discuss aches and pains potentially related to self propelling.

“As I’m doing my mat assessment, if I’ve gotten a good history, I can say, ‘I see you’ve had some minor shoulder issues or moderate shoulder issues in the right shoulder. I’m going to move your arm: Does this hurt?’”

Having a family member present can be helpful to this part of the process, Merring noted, because “A lot of times, people in chairs have accommodated for so long that they think [discomfort] is normal. Maybe [a family member] says, ‘I see you grimace’ or ‘Three or four times a week, you do complain of shoulder pain when you’re going to bed.’ That extra set of eyes can give you the data you need to help determine what this person could use.”

Pressure Injury Considerations

Pressure injury risk is always a concern for wheelchair users, and therefore is a critical consideration when choosing between power and manual mobility.

“If a person wants manual mobility and they have a history of pressure injuries,” Merring said, “I have to make sure I’m helping them optimize their seating system so that they can have the best cushion and the best postural support. People sometimes forget that an open back angle can increase pressure over the sacrum. A scoliotic curve that’s not corrected can increase pressure over an IT [ischial tuberosity]. So the cushion is important, the backrest is important, how they sit in their current seat is important.

“After all that, can the person do the pressure reliefs that they’re supposed to be doing frequently and adequately? If they can’t, I may start leaning toward power tilt, or if they’re really pushing for [manual], I start talking about a training program or a maintenance program so they get some feedback. We’ll do our evaluations with pressure mapping, and it’s incredible that when you put a pressure map under someone and have them lean to the right, lean to the left and lean forward, you can see that even without completely pushing up, you can clear all pressure from underneath each IT just from leaning left and right. We’ll use that for training also. If the person really wants manual, has used manual and has an issue with pressure relief — then after we’ve made sure the seating system we’re going to order is optimal, we’ll use pressure mapping for some additional training.”

Merring also observes the client’s shear risk during the assessment.

“When I do my mat assessment, I get my initial picture of what it’s like for this person to do a transfer,” he said. “I get a baseline, because they’re usually transferring from one surface to another level surface. If I see a little bit of struggle or a little bit of drag, I may have them repeat it. And if time allows, I like to see how they get in and out of a car, as well. Are they dragging, are they lifting? Do we have to think about floor-to-seat height because the car transfer is a major transfer or the toilet transfer is a major transfer?”


So when the conversations have taken place, the mat eval is finished, the pressure injury history has been considered — what ultimately determines whether power or manual mobility is better for a given client?

“The mobility need for people with incomplete cervical SCI will depend upon the completeness of injury and subsequent strength,” Merring said. “Lower cervical spine injuries will depend upon their upper body and postural strength post injury.”

And while the power vs. manual question commonly comes up for lower-cervical SCI, Merring said that isn’t the only scenario.

“Something I’ve been considering more lately are people with higher thoracic injuries secondary to the extent of compromised postural strength and the effect that has on the shoulders during propulsion and other issues,” Merring said. “Postural strength is an important aspect of wheelchair propulsion that can be overlooked. Impaired postural strength can be improved by providing optimal positioning with ergonomic seating through the frame, cushion and backrest. Improved postural position improves a person’s ability to propel, allowing for someone with compromised muscle strength to possibly propel a wheelchair if it is optimally configured.”

A Boost from Power-Assist

In the question of power vs. manual mobility, power-assist systems for ultralightweight chairs can offer a sort of hybrid intervention, while possibly broadening the population of wheelchair users who can self propel.

“Power-assist is becoming more prevalent, for good reason,” Merring said. “I consider power-assist at every assessment, even as low as initial injuries at T3-T4. If you think of where T3-T4 is, that’s the nipple line. Think of folding over, where you have muscle on top and paralyzed muscle underneath: You’re kind of folding in the middle. So postural strength is very compromised, and then because the postural strength is compromised, bilateral upper extremity is very compromised as well.

“As you bend in your thoracic spine, you collapse the space between your scapula and your ribcage. If you collapse that space, you are inhibiting the ability of the scapula to do upward rotation. Basically, kyphosis causes an impaired joint that allows for a lot of impingement to happen. If your muscle below T3-T4 doesn’t work, you’re already pre-dispositioned for a non-optimal shoulder propulsion.”

Enter the power-assist system, which Merring said he considers whenever he’s thinking about recommending an ultralightweight chair, regardless of the potential user’s age or shoulder history.

Merring said of power-assist, “Can I get this ahead of time to decrease the demand on the shoulders and also improve the ability for this person to go longer distances for longer times? It definitely crosses my mind for each evaluation.

“A lot of the [younger SCI patients] that I see [in clinic] are college students. They have to be able to get from one class to another relatively quickly. They’re trying to manage phone calls, they’re propelling, they’re carrying backpacks. Any sort of device that saves the physical demands and exertion, and allows them to be more functional, should be brought to the table during the evaluation.

“As the technology continues to get better and smaller and hopefully cheaper — reimbursement also sometimes comes down to the costs of things — hopefully, power-assist becomes more reimbursable. And as the evidence shows that someone who pushes 2,000 to 3,000 times a day can, without a doubt, be assisted in maintaining their shoulder integrity and postural integrity and be more functional and give back into society, we should start to see more chairs [using] it.”

What Is the Better Option?

Manual and power mobility have their strengths and weaknesses. Ultralight chairs undoubtedly have an easier time fitting into smaller everyday spaces indoors and into cars; power chairs conserve a consumer’s energy and offer powered positioning and pressure relief.

“Every decision starts with that person and what their MRADL needs are specifically,” Merring said. “That’s what’s going to drive your decisions, ultimately. What do you need to do the majority of the time?”

Merring acknowledged that choosing a power chair can make transportation plans more complicated, and he said that as a rehab director, he made sure to provide new power chair users with resources, such as community transportation options. “The worst-case scenario is we give them a power chair for home, and, because that’s all their funding will cover, they buy a hospital chair to go to doctor’s appointments,” he said. “That’s the worst case scenario.”

But despite those potential inconveniences, he said he would recommend power mobility if it was the better choice overall.

“If [using a manual chair] is really compromising function and compromising health, and the medical necessity is there for power, I’d much rather be the advocate for power so the mobility isn’t sacrificed, and function isn’t sacrificed, and pressure relief isn’t sacrificed,” he said.

Because deciding between manual and power mobility is such a critical decision, Merring said he encourages the seating and mobility team to take the time needed to gather all the information they can.

“When I do my evaluations, I do a 90-minute evaluation the first time, and I try not to put any pressure on myself or the patient or the ATP to make all our decisions that day,” he said. “We’ll bring [the client] in, we’ll do the initial evaluation. If it takes 90 minutes just to discuss what the problems are and what the current chair is, and we only do a measurement, that’s perfectly fine with me. And then I bring them in for a second and third visit and start getting some of that other information.

“Don’t feel like you have to do this in one day. Ask the tough questions. Have a conversation with the person. And know that there’s no one specific formula for [finding the right answer], just trial and error.”

This article originally appeared in the May 2017 issue of Mobility Management.

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