ATP Series

For Good Measure

A Seating & Mobility Evaluation May Start with Taking Client Measurements -- But That's Only the Beginning

• By Laurie Watanabe
• Mar 01, 2014

So many things have to come together to create a successful complex rehab seating or mobility system that it’s tough to count them all. Every conversation between members of the seating & mobility team, every meeting with the client and caregiver, every discussion of the client’s presentation and prognosis, every visit to the home and school or workplace where the technology will be used, every trial of a seating system, mobility base or accessory: They all contribute to a satisfactory outcome. And if they’re neglected, they can result in a less than successful outcome: a seating & mobility system that needs repeated revisions, one that never feels quite right to the consumer, and perhaps even a system that’s eventually abandoned.

As with many large-scale projects, building a successful seating & mobility system might start with something quite small — maybe something as small as a half or quarter inch (or a few centimeters). After all, at the heart of complex rehab technology is a customized fit, a system so precisely built for the individual that it fits one and only one client.

Getting the correct fit requires obtaining the right set of client measurements. That sounds easy enough — but human beings are not composed of straight, still lines or precise, unchanging angles. And therein lies the challenge for the seating & mobility professional.

What Measurements Are Required?

As seems to be the case so often in the realm of seating & mobility, collecting client measurements would seem to be one part science and one part art — meaning that while there is indeed a set of “must-have” measurements, clinicians also have their own personal ideas and preferences regarding which measurements are most crucial and how the measurements should be taken for greatest benefit and accuracy.

Mario Ouellette, the CEO and founder of Physipro in Sherbrooke, Quebec, has specialized in seating and has 25 years’ experience in clinical evaluations.

Asked for a summary of measurements that ATPs and clinicians need to take, Ouellette says, “The most important measurements to collect are the femoral length, the trunk width, the pelvic width and the armpit height. With those measurements it is possible to manufacture a seat and a back system that also include pelvic and thoracic supports.”

For the pelvis, Ouellette adds, two measurements should be taken: first, “When the muscles are relaxed, normal.” And second, “In compression. The measurement in compression of the flesh allows (the clinician) to determine to what extent the patient can control pain if there is a need to correct pelvic rotation. It is necessary to take compressed measurements in order to correct certain pathologies.”

Ouellette says other important measurements include:

• Femoral length: measured from the pelvic region to the popliteal fossa.
• Popliteal height: measured from the popliteal fossa to the plantar area. This measure allows determination of the seat-to-floor height.
• Length and width of the foot to determine custom footplate measurements or if the patient needs any corrective foot orthoses.
• Top of the iliac crest to the trochanter: This measurement will allow the determining of the height of the pelvic support.
• Elbow rest height: From under the trochanter to the elbow of the patient. The arms have to be at 90°. Determines the armrest measurements.
• From under the trochanter to the armpit to determine the thoracic supports height.
• From under the trochanter to the shoulder to determine the backrest height.

Robin Skolsky, PT, ATP, Shepherd Center in Atlanta, says basic measurements to consider are “seat width, seat depth, lower leg length, legrest angle (knee flexion/extension limitations), trunk height, shoulder width, chest width and possibly depth (if using laterals or contoured back), elbow height (if using armrests), hip/back angle, seat-to-floor height front and rear, foot plate size/length and angle.”

Skolsky adds, “Lateral thoracic support height setting is an important measurement to record as well — specifying right vs. left and acknowledging the cushion the client will be using. Knowing what each measurement actually means, and how it was taken (shoulder height from seat pan while seated on a cushion vs. on a mat table, or seat depth being actual vs. what is recommended for the seating system) is paramount in creating an eff ective wheelchair and seating system. Asymmetries should be noted and accommodated when appropriate.”

It’s All in the Details

Indeed, while gathering measurements might seem like a straightforward task resulting in black-and-white answers, Megan Kutch, MS, OTR, director of Quantum Rehab, points out that there are many additional subtleties that, if they’re noticed and noted, can make a difference in the outcome.

“You should also always have your client’s height and weight to determine the appropriate power base,” Kutch says. “In addition, note the body type that the individual you are working with has. If he or she has a lot of soft tissue in the buttocks region, you may need to take a measurement from the seat to the top of the buttocks. Even though there are standard measurements that you must take, you also have to consider each individual’s needs and take any measurements that you feel you may require during the evaluation.”

Skolsky says that it’s important to complete the measurements “with the client in the ideal sitting posture. Reduce flexible deformities to ensure the most effective sitting posture will be facilitated in the custom system. If hip width is significantly narrower or wider than shoulder/trunk width — this can be accommodated in an endomorph or mesomorph system, but can add additional challenges as well. Photos can assist in explaining what positioning goals you are looking to achieve, especially if a different therapist will be involved in the fitting.”

While it’s not a measurement, per se, Skolsky adds, “Knowing if someone will be propelling the chair with their upper extremities, lower extremities, upper and lower extremities, on one side, etc., can impact set-up of the chair.”

The client’s measurements aren’t the only important ones that the seating & mobility team needs to know and to consider, Skolsky says. “The overall length of the frame can be an influencing factor in selection and function for a client as well. Some manufacturer frames, for the same-size seating, will be longer than others — and some manufacturers have options on the frame. The correct selection/recommendation is important! These options should be addressed when working with ATPs/therapists who have good knowledge in different equipment.”

How Important Is Adjustability?

Getting all of those client measurements is just the beginning of the seating & mobility numbers game. For reasons ranging from the practical to the clinical to ones demanded by funding sources, the seating & mobility team must take those carefully obtained measurements and then decide how much adjustability they want to build into the system.

“It is important to have systems with more adjustability for several reasons,” Ouellette says. “The adjustability of a system allows adapting to the patient’s morphology through time. For example, if the patient loses or gains weight or grows, it’s important that the system can be adjusted accordingly.”

He adds that funding sources commonly have certain expectations of the systems they’re paying for: “Another important aspect is the insurance provided to the ATPs/clinicians when a system is adjustable. It provides more security if the system can respond more adequately to the specific needs of the patient, which can change over the course of a progressive illness or when postural abnormalities increase.”

And on a more practical, everyday note, Ouellette points out, “Depending on the season, the [wheelchair user] will wear different clothes. So the system has to allow enough space depending on if the [consumer] has a winter coat or lighter clothing for summer.”

Kutch says having some seating adjustability can help both the client and members of the healthcare team.

“Built-in adjustability on a seating system is the key to providing the comfort that the individual needs,” she explains. “It provides the support needed for the person to feel stable while performing their [activities of daily living]. Having greater adjustability allows ATPs and clinicians to make these adjustments while the client is in the seating system, both at the time of original fitting, as well as if needs change.

“The option to increase the client’s seat depth by ½" or greater to accommodate for a thicker back cushion, quickly shrinking or growing the seat width to accommodate for weight fluctuations, internally or externally rotating the armrests, and making adjustments to the articulating foot platform so the client is comfortable when fully extended are just some examples of dialing in the seating system for the client.”

Trying to anticipate the need for adjustability is part of the job when working with consumers who require custom-fitted equipment, Kutch adds.

“The majority of your clients in complex seating systems need more adjustability than standard systems because their diagnoses may in some cases progress over time. By providing a seating system that off ers adjustments that can be made quickly, the client can remain in their seating system while various modifications can be made by the ATP or clinician. Another important factor is the option to add specialty electronics, such as a head array, to their power base if they no longer have the function to drive with a hand control.”

The seating team, Skolsky says, has the challenge of striking a balance between enough adjustability to meet a client’s current and possibly future needs, but not so much built-in adjustability that the system will be unwieldy or ineffective.

“Adjustability is very important early on, but can be less desirable for someone who has been using a chair for many years and knows how they like to sit. For instance, someone who has a spinal cord injury will change significantly early on — whereas someone with multiple sclerosis might continue to change for years. Obviously, if someone is still growing there is a definite need for adjustability and growth, but it is important not to prescribe a chair/seating system that someone will be expected to grow into — just as you would not buy shoes a size or two too big, as they would not be effective.”

What Other Measurements Are Critical to a Good Outcome?

Of course, successful seating & mobility systems are more than just the sums of their users’ various measurements. Other measurements are critical as well.

“You definitely need to make sure that the client has the capability to navigate within their home environment,” Kutch points out. “The ATPs and clinicians have to make sure that the base and seating system will fit through the doorways within the home, so that is a vital measurement to take. Also, look at the turning radius of the chair and make sure the client has ramps set up so that he or she can safely transition from in the home to outside.”

Speaking of the outdoors, Kutch says the seating & mobility team needs to take their clients’ other environments into consideration: “They would also need to discuss or visit the client’s work or school to make sure the power base can be used within those environments. Discussing modifications that need to be made to enhance a client’s experience in the workplace or classroom should also be considered.”

To ensure that the mobility base fits well into a home and supports its user’s activities, Ouellette says, “At the functional level, it is necessary to have measurements such as the kitchen counter height, the bed height, the door frame size, etc. Does the patient have an adapted bathroom?”

Depending on the nature and locations of the consumer’s daily activities, seating & mobility equipment may also need to be transported — which can require taking and incorporating an entirely new set of measurements.

“Transportation is also a very important factor for the client,” Kutch says. “The ATP/clinician will need to discuss this with the client and determine if he or she will be using public transportation or a van, and confirming dimensions suitable for such transport.”

“It is typically recommended that a person receive their custom chair and then shop for a vehicle, if possible,” Skolsky says. “The overall height of a client in a chair is a measurement that is often sought, but typically cannot be provided definitively, until they have their custom equipment. A typical limiting factor in accessibility is the overall width of the chair — however, the chair must be prescribed to fit the client, taking into consideration the width of their doorways, but ultimately the body measurements dictate the wheelchair measurements.”

Numbers vs. Your Client’s Uniqueness

If there’s any part of seating & mobility’s big picture that should be cut and dried, you’d think it would be the precise numbers of inches and centimeters that ATPs and clinicians carefully record during evaluations.

And those inches and centimeters, or more often those quarterinches and millimeters, can add up to a wonderfully empowering positioning and mobility system…when the professionals on the receiving end combine those numbers with their own observations and experiences.

“All measurements are critical when you are configuring complex seating for your client,” Kutch says. “When a client is using a power articulating foot platform, adjusting the degree of articulation is very important. I have seen cases where the client elevates their legs and ends up with their knees bent in a position that is very uncomfortable for them when they reach the end range of elevation. By making a few minor adjustments, comfort level and position can be significantly improved. Ensure that your client will be comfortable and stable in their seating system, with the ability to functionally perform their activities of daily living. If a measurement is slightly off , it can impact the client in their seating system on a daily basis.”

“Overall, it is very important for a client to work with a supplier and a therapist to finalize wheelchair recommendations,” Skolsky says. “The team can bring the most eff ective means for recommendations rather than one alone.

“It is also extremely important to have the same ‘players’ in the final fitting. Often, people feel they are comfortable and well served in their equipment until minor changes are made that further enhance their comfort and function — changes unexpected by the client.”

This article originally appeared in the March 2014 issue of Mobility Management.