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

updated 11/11/2024.

Our past two blogs have addressed clinical benefits of Dynamic Seating, specifically the evidence for Dynamic Seating improving Postural Control and Function. Several of our past blogs have addressed using Dynamic Seating to prevent client injury, typically by exploring specific case studies. In this blog, we will take a look at the evidence for this clinical benefit.

Pain

• The Ridilla, et al. study (2024) indicated an increase in self-relief of pressure after prolonged seating in a response to increased pain.
• Frank, et al. (2012) found that most power wheelchair users in their study experienced pain and that one strategy that reduced pain was changing position.
• Movement has been shown to decrease pain in wheelchair users (Lyons, et al., 2017; Frank & DeSouza, 2017).
• Incoronato (2007) found a reduction in pain with use of a specific dynamic seating system in a retrospective study.

Joint and Bone Injuries

The forces from extension on the client’s body can lead to injury (Hong, 2006, Lange, 2021). Extension causes tremendous force through joints and can even lead to joint damage and bone fractures.

• Further injuries were prevented in a client using dynamic seating who had a history of injuries secondary to extreme extension forces (Lange, 2021).

Arthritis

Adults with CP are more likely to experience arthritis compared to non-disabled adults (31.4% vs. 17.4%, Peterson, et al., 2015) (Whitney, et al., 2018). Extension causes tremendous force through joints that is unrelieved in a static seating system. These studies could form the basis for future research to determine if dynamic seating could diffuse extensor forces to specifically lessen forces occurring in the joints.

Concussions and Neck Injuries

Repeated and strong impacts between the head and the head support could even lead to concussions. A concussion can occur when the head collides with force against a surface. Some clients using wheelchairs bang against the head pad with significant force, perhaps even enough force to cause brain injury. Degree of force and repetitive impacts only increase risk of injury. Dynamic components absorb force, reducing this risk. Clients who extend against a head support with sustained force are also at risk of neck injury (including strains) due to forces occurring through the soft tissue and vertebrae of the neck.

Arm Injuries

Decreased upper extremity dystonic movement found by Avellis, et al, 2010 and Cimolin, et al., 2009, could reduce injury caused by large and uncontrolled upper extremity movements.

Shear Injuries

Shear forces can occur as the client extends against a static surface, which increases the risk of skin and tissue injury. Cimolin et al. (2009) used quantitative movement analysis to compare movement during extensor thrust using a dynamic back support and using a rigid back support and found increased vertical trunk movement (shear) during extension with the rigid back support.

• Cimolin et al. (2009) used quantitative movement analysis to compare movement during extensor thrust using a dynamic back support and using a rigid back support and found decreased vertical trunk movement (shear) during extension with the dynamic back support.
• Dynamic Seating allows movement while maintaining contact with the support surfaces, providing stability, and reducing shear forces (Hahn, 2009; Cimolin, et al, 2009; Chen, et al., 2018).
• Dynamic Seating can reduce shear forces, as the seating surfaces move with the client, maintaining improved contact (Lange, et al., 2017).

Preventing Tipping Related Injuries

Many clients with intellectual disabilities tend to move a lot and frequently rock in their wheelchair seating system. This rocking movement may be so strong as to literally “bounce” a manual wheelchair across the room and can lead to the wheelchair tipping over and causing client injury. Dynamic seating moves in response to this rocking movement, which may reduce the risk of tipping the wheelchair over.

In a 1997 study by Gaal et al., wheelchair “tips and falls” were the most commonly found wheelchair incidents, followed closely by component failures (Gaal et al., 1997). While this study did not isolate wheelchair incidents in any single population of wheelchair users, it highlights this as one of the main potential causes of wheelchair rider injuries.

 

So, what’s the bottom line? Dynamic Seating can reduce the risk of client injuries, an extremely important clinical benefit!

Check out our Quick Class on Preventing Client Injury

References:
Please refer to our Literature Review which includes all the references cited here.