The Onion of Seating

by Amy Ortego, OTR/L, ATP, and Sara Zwart, OTR/L, ATP

Over the years, the wheelchair and wheelchair seating industry has changed dramatically. At one time, commercial seating options were much more limited and custom seating departments were needed much more frequently. With improvements in commercial products, the addition of commercially available custom options, and decreases in funding, truly custom departments, dedicated only to evaluating and treating for wheelchair needs, are fewer and farther between. It should be said that the authors of this article come from one of those departments. Our therapists have the whole range of seating options available to them, including seating that is fabricated and upholstered in-house.

While it is not required to have a custom seating department or years of expertise in seating to give your client a quality piece of equipment, it certainly helps! The layers of complexity for each client need to be peeled away like an onion before conclusions can be made about what will be most appropriate for that individual. Some of these considerations are more obvious than others.

Layer 1) The Client

When making decisions about what seating is going to be most appropriate for your client, the attributes of that client should be the most obvious aspect to consider. However, this doesn’t make it any less complex. Once you decide what support they need based on their postural control and asymmetries, you also need to determine how much correction the person can tolerate, what may help or hinder their function, and whether or not the caregiver can transfer the person in and out of the seating and transport it. Given that children grow and change quickly, the age of the client is also a factor. Total contact custom seating, such as a poured foam system, may not be the best option because it is grown out of too quickly. The type of wheelchair in which the seating will be mounted is also a consideration. Total contact seating is also difficult to use when the chair is equipped with recline. Even with the best of systems, the contours do not provide the same support in recline as they do in the upright position.

Layer 2) The Variety of Options

Even once commercial, planar seating has been ruled out and you know that your client will need custom seating, there are still a number of options available. The next section of this article will go through the pros and cons of several styles, since each one has good rationale and contraindications for its use. It is helpful to have some experience with each option as not all of the contraindications are published in any literature or by the manufacturer. Knowing how each of the components will fit together like a big 3-dimensional puzzle is also important. Then take into consideration how quickly there are new products added to the market while others are being taken off. Keeping up with the changes can be difficult, especially if it is something that you only do once in a while. Seating departments have a distinct advantage because they tend to be kept informed by the manufacturers themselves.

Layer 3) Insurance and Documentation

As much as we hate to admit it, insurance coverage has a bigger influence on our decision-making than we would like. Not only do they determine how much they are willing to pay for seating (which ultimately determines which options are able to be provided), they also determine what is required in order to qualify for the seating. The type of insurance may dictate what kind of documentation is needed. In Michigan, Medicaid requires a specific form for any mobility and seating requests. Much like in gourmet dining, presentation is everything. If the information is not given to the insurance company in just the right way, all could be for naught. Having a good chef on your side who knows their way around the kitchen and can give the insurance company what they want the first time around (at least most of the time) is a good thing.

Choosing the Main Course

OK, so now you have skillfully peeled away the layers of your onion and have determined that your client needs custom seating. Now what? There are any number of different custom options and combinations of supports that can be considered, just like there are millions of ways to use an onion. Whole articles could be written on any one component, so this article will focus on custom seats and backs, as this is the “main course” of the seating system and all other components are built off of it.

Custom Planar

One choice is a custom planar system. In this type of seating it starts with a flat or minimally contoured base with layers of foam built on top of that. These layers of foam can be custom positioned to accommodate for mild to moderate postural asymmetries. Different densities can be used to have an extra soft layer on top for those with bony prominences close to the skin or a firmer density underneath to provide more support, such as an anti-thrust ledge. If needed, one area of foam can be carved out to allow for better pressure relief or an air cushion can be used as an insert into the foam cushion for improved pressure distribution. This type of cushion typically can be easily adjusted for growth without compromising positioning and support.

The downside of this type of system, however, is that it can be heavy and bulky. It is not typically used for people who are active and independent with their wheelchair propulsion in a manual wheelchair because of the weight that it adds to the chair. It also has a limit to how supportive it can be for those with severe asymmetries and can be difficult to keep clean since the foam is upholstered directly to the base and does not have an additional removable cover.

Full Contact Foam

The full contact foam design can be done in a couple of different ways. Most commonly it is done by making a mold of the person’s shape and sending the shape to an outside company to fabricate a cushion to fit the person’s body or by creating the cushion using liquid foam that is poured around the person. This type of seating provides full body contact, which provides an even pressure distribution and can accommodate for asymmetries in multiple planes. As a result, it is a highly supportive system. In the cases where the liquid foam is used, the person’s posture and support can be assessed and modified before it is completed, which improves the quality of the final product.

This system, however, tends to be even heavier and bulkier than the planar system. There is little adjustment that can be made for growth, and it has a lower tolerance for variances in clothing. For those familiar with the Michigan climate, this can be a significant factor for those living in places where there is such a wide temperature variation.

Low Profile Full Contact

The last style that will be discussed is a low-profile, full-contact system. The backrests are only approximately 1 inch thick and consist of a contoured, sturdy plastic and a thin pad. The seats are designed to off-load bony prominences and are made of a high-density foam. The attachment hardware is very adjustable, allowing the backrest to be rotated and shifted in all directions. The cushions themselves are firmer than its competition, which provides the client with more support than a foam-based system. For those with significant tone, this can be needed in order to maintain a functional position. The slim profile of the system allows for even active, independent users to have the added support of a full-contact system. It is also much more easily cleaned when there are issues with incontinence, and it is relatively breathable.

One of the benefits of this system is its firmness, but it is also one of its risks. If a person is not positioned consistently in the appropriate position, the client would be at higher risk of injury with this system than in a foam system. While appropriate positioning is always important, the primary caregivers don’t always have control of this. The adjustability of the hardware can also be difficult when it comes out of adjustment. An unskilled caregiver might not be able to get it back into the appropriate position. Unfortunately, pricing can also be problematic with this system. Some insurance companies do not pay enough to cover the costs.

Case Study – Danielle

Cooking analogies aside, you might be wondering how this looks in the real world with a real person. So let’s look at Danielle, a 26-year-old woman with cerebral palsy, who has been seen by our department since she was a year and a half old. Over the years she has had 24 evaluations and 12 fitting sessions, which has helped her to get six different custom seating systems, one stroller, and three tilt-in-space wheelchairs. All of these systems have been contoured planar systems with minor changes made over the years. She is now awaiting approval for her seventh seating system and fourth tilt-in-space wheelchair. This time she will have a poured foam backrest with a seat that is part foam and part air-filled cushion. A full-contact system has not been appropriate until now due to normal growth during childhood and adolescence. She would have required far more than six seating systems over these years if she had full-contact systems.

Part of the rationale for doing it now is that her weight and growth are stable. In addition, she has had skin irritation on the backs of her arms from her laterals. A full-contact system will be able to support her posture without hardware under her arms. The combination seat will be new to Danielle. She has always had all foam seats with an anti-thrust ledge. However, she has now graduated from school, where she was taken out of her wheelchair frequently throughout the day, and will now be spending more time in her wheelchair. This increases her risk of pressure injury, which is why the air cushion is now recommended. A seat that is only an air cushion would not be stable enough to prevent her from sliding forward in her seat. The foam section in the front of the cushion will assist with maintaining a functional posture.

Unfortunately, as we have been writing this article Danielle’s request to her insurance company for a new chair and seating has hit multiple roadblocks with multiple denials. At this point it is only speculation for the rationale for these roadblocks. However, in the past she has had a combination of commercial and state-funded insurance. Now that she is older, Danielle only has state-funded insurance, which has its own set of requirements for justification. Despite everything being in her favor, with a long history of needing equipment, Danielle is still waiting. RM

Amy Ortego, OTR/L, ATP, is a graduate of Texas Woman’s University. She worked as a pediatric occupational therapist at the J.D. McCarty Center in Norman, Oklahoma, for 7 years before returning home to Michigan. She has worked at Mary Free Bed Rehabilitation Hospital in Grand Rapids for almost 32 years. Ortego is an occupational therapist in the hospital’s OrthoSEAT department, providing evaluation for mobility devices and custom seating with experience in evaluating for AAC as well.

Sara Zwart, OTR/L, ATP, is an occupational therapist in the OrthoSEAT seating clinic at Mary Free Bed Rehabilitation Hospital, where she has worked for the last 4 years. Zwart previously worked at a small inpatient rehabilitation facility but developed a passion for seating during a medical mission trip to Honduras. Since then, she has gone to Thailand and China with Wheels for the World and is one of their Chair Corp Volunteers, helping with the collection of donated mobility equipment that will be distributed abroad. Sara earned a master’s degree in occupational therapy from Grand Valley State University. For more information, contact [email protected].