Michelle L. Lange, OTR/L, ABDA, ATP/SMS

It has been established that Dynamic Seating absorbs and diffuses force. This intervention is often used to prevent client injury and equipment breakage, as well as to provide movement. Other clinical benefits of Dynamic Seating for some clients are decreased energy consumption and weight gain.

A Clinical Example

Let’s imagine a client who is extending within their wheelchair seating system, as Tyler is in this photo. As movement meets static, unyielding seating surfaces, muscle tone tends to increase. Some clients we work with are literally ‘standing’ in their wheelchair seating systems! This takes quite a bit of energy and calories.

If you are sitting behind this client while they sit on the edge of a mat table, for example, and try to prevent the client from extending, you are going to lose! As clinicians, we allow the client to extend (providing a yielding surface by moving our body) and then assist the client back to upright after tone relaxes. Dynamic Seating provides a yielding surface, diffusing tone and force, and then assists the client back to upright in much the same way. This reduces energy consumption and can even result in some much-needed client weight gain.

Why is decreasing energy consumption important?

When a wheelchair user is exerting a great deal of energy within their seating system, this leads to fatigue, decreased endurance, increased calorie burn, decreased function, and reduced focus and attention. These unrelieved forces can also lead to pain and even injury – if the client is positioned to inhibit muscle tone and movement patterns, the forces have nowhere to go but the joints.

Decreasing energy consumption conserves energy for function, focus, and attention throughout the day. For many clients using Dynamic Seating, pain may also be reduced.

Why is weight gain important?

Too many people with increased muscle tone are underweight, often because of very high caloric output throughout their day. Despite high calorie diets and even tube feeding, weight gain may be limited. As much as many of us are trying to lose weight, adequate weight is important for nutrition, energy, development, and function. When a client is underweight, bony prominences are even more prominent and pressure injury risk is increased. The client may be more prone to illness or infection and heal more slowly.

Dynamic Seating

Anecdotally, I and many of my colleagues have noted the following in clients who have received dynamic seating:

• Less active extension and extraneous movement, indicating less energy consumption
• Weight gain

One client I work with gained 10 much-needed pounds in the month following delivery of his dynamic seating components!

What does the Research Say?

Anecdotal experiences are great, but is any of this supported by evidence? Dynamic seating has been found to reduce energy consumption and fatigue (Ferrari, 2003). Another study found that clients with increased extension, who did not have dynamic seating, were able to exert up to 200% of their body weight against the back support and up to 600% of their body weight against the foot supports during extension (Samaneein, et al., 2013). That is a great deal of unrelieved force and energy expenditure! Medically, dynamic seating has even been found to improve digestion (Incoronato, 2007), which could lead to improved nutrition and even weight gain.

An important goal of wheelchair seating is energy conservation. This allows the client to have adequate energy for functional tasks and not burn excessive calories, which could result in the client being underweight. Dynamic Seating is an important part of achieving this goal.

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References:
1. Ferrari A. (2003). In terms of posture and postural control, Giornale Italiano di Medicina Riabilitativa, 17 (1); 61-7.

2. Samaneein, K., Greene, P., Lees, K., and Riches, P. (2013). Comparison of Imparted Forces between Rigid and Dynamic Seating Systems during Activities of Daily Living by Children with Cerebral Palsy. Congress of the International Society of Biomechanics, Brazil.

3. Incoronato (2007) Dynamic seating for children and adults with multiple disabilities. Orthopedic technology, 92-97.